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1
Westerlund, Per. "Condition measuring and lifetime modelling of electrical power transmission equipment." Licentiate thesis, KTH, Elektroteknisk teori och konstruktion, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-167136.
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The electric grid is important in modern society, so the outages should be few. The transmission grid should have a real high availability, since it transports electrical energy across the country. Then, it is difficult to plan outages for maintenance and installation. This thesis lists twenty surveys about failures of circuit breakers and disconnectors, with data about the cause and the lifetime. It also contains a survey of about forty condition-measuring methods for circuit breakers and disconnectors, mostly applicable to the electric contacts and the mechanical parts. As there is no published method to monitor the electric contacts at voltages around 400 kV, a system with IR sensors has been installed at the nine contacts of six disconnectors. The purpose is to avoid outages for maintenance by estimating the condition of the contacts while the disconnectors are still connected to high voltage. The measured temperatures are collected by radio and regressed against the square of the current, since the best exponent for the current was found to be 2.0. The coefficient of determination $R^2$ is high, greater than 0.9. This gives for each contact a regression coefficient, which can serve as an estimate of the condition of the contact. The higher the coefficient is, the more heat is produced at the contact, which can damage the material. This enables a ranking of the different contacts and shows which the worst ones are. This coefficient can also give a dynamic rating of the disconnector.Elnätet är viktigt i det moderna samhället, så antalet avbrott bör vara lågt. Särskilt stamnätet bör ha en särskilt hög tillgänglighet, då det transporterar elektrisk energi tvärsöver landet. Då blir det svårt att planera avbrott för underhåll och utbyggnad. Denna avhandling tar upp tjugo studier av fel i brytare och frånskiljare med data om felorsak och livslängd. Den har också en översikt av ett fyrtiotal olika metoder för tillståndsmätningar för brytare och frånskiljare, som huvudsakligen rör de elektriska kontakterna och de mekaniska delarna. Eftersom det inte finns någon beskriven metod för att övervaka elektriska kontakter för spänningar på runt 400 kV, har ett system med IR sensorer installerats på de nio kontakterna på sex frånskiljare. Målet är att minska antalet avbrott för underhåll genom att skatta skicket hos kontakterna, när frånskiljarna fortfarande är kopplade till högspänning. De uppmätta temperaturerna tas emot genom radio och behandlas genom regression mot kvadraten av strömmen, då den bästa exponenten för strömmen visade sig vara 2,0. Förklaringsfaktorn $R^2$ är hög, över 0,9. För varje kontakt ger det en regressionskoefficient, som blir en skattning av kontaktens skick. Ju högre koefficienten är, desto mer värme utvecklas det i kontakten, vilket kan leda till skador på materialet. Kontakternas olika koefficienter ger en rankordning dem och därmed en möjlighet att prioritera vilken frånskiljare som ska underhållas först. Systemet kan också användas för att minska eller öka den tillåtna strömmen baserat på skicket.
QC 20150522
2
Lindquist, Tommie. "On reliability modelling of ageing equipment in electric power systems with regard to the effect of maintenance." Licentiate thesis, Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-273.
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Lindquist, Tommie. "On reliability and maintenance modelling of ageing equipment in electric power systems." Doctoral thesis, Stockholm : Electromagnetic Engineering, Elektroteknisk teori & konstruktion, Kungliga Tekniska högskolan, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4688.
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Westerlund, Per. "Condition measuring and lifetime modelling of disconnectors, circuit breakers and other electrical power transmission equipment." Doctoral thesis, KTH, Elektroteknisk teori och konstruktion, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-214984.
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The supply of electricity is important in modern society, so the outages of the electric grid should be few and short, especially for the transmission grid. A summary of the history of the Swedish electrical system is presented. The objective is to be able to plan the maintenance better by following the condition of the equipment. The risk matrix can be used to choose which component to be maintained. The risk matrix is improved by adding a dimension, the uncertainty of the probability. The risk can be reduced along any dimension: better measurements, preventive maintenance or more redundancy. The number of dimensions can be reduced to two by following iso-risk lines calculated for the beta distribution. This thesis lists twenty surveys about circuit breakers and disconnectors, with statistics about the failures and the lifetime. It also presents about forty condition-measuring methods for circuit breakers and disconnectors, mostly applicable to the electric contacts and the mechanical parts. A method for scheduling thermography based on analysis of variance of the current is tried. Its aim is to reduce the uncertainty of thermography and it is able to explain two thirds of the variation using the time of the day, the day of the week and the week number as explanatory variables. However, the main problem remains as the current is in general too low. A system with IR sensors has been installed at the nine contacts of six disconnectors with the purpose of avoiding outages for maintenance if the contacts are in a good condition. The measured temperatures are sent by radio and regressed against the square of the current, the best exponent found. The coefficient of determination $R^2$ is high, greater than 0.9. The higher the regression coefficient is, the more heat is produced at the contact. So this ranks the different contacts. Finally a framework for lifetime modelling and condition measuring is presented. Lifetime modelling consists in associating a distribution of time to failure with each subpopulation. Condition measuring means measuring a parameter and estimating its value in the future. If it exceeds a threshold, maintenance should be carried out. The effect of maintenance of the contacts is shown for four disconnectors. An extension of the risk matrix with uncertainty, a survey of statistics and condition monitoring methods, a system with IR sensors at contacts, a thermography scheduling method and a framework for lifetime modelling and condition measuring are presented. They can improve the planning of outages for maintenance. Finally a framework for lifetime modelling and condition measuring is presented. Lifetime modelling consists in associating a distribution of time to failure with each subpopulation. Condition measuring means measuring a parameter and estimating its value in the future. If it exceeds a threshold, maintenance should be carried out. The effect of maintenance of the contacts is shown for four disconnectors. An extension of the risk matrix with uncertainty, a survey of statistics and condition monitoring methods, a system with IR sensors at contacts, a thermography scheduling method and a framework for lifetime modelling and condition measuring are presented. They can improve the planning of outages for maintenance.Elförsörjningen är viktig i det moderna samhället, så avbrotten bör vara få och korta, särskilt i stamnätet. En kortfattad historik över det svenska elsystemet presenteras. Målet är att kunna planera avbrotten för underhåll bättre genom att veta mera om apparaternas skick. Det är svårt att planera avbrott för underhåll och utbyggnad. Riskmatrisen är verktyg för att välja vad som ska underhållas och den kan förbättras genom att lägga till en dimension, sannolikhetens osäkerhet. Risken kan minskas längs med varje dimension: bättre mätningar, förebyggande underhåll och mer redundans. Antalet dimensioner kan igen bli två genom att följa linjer med samma risk, som är beräknade för betafördelningen. Denna avhandling tar upp tjugo studier av fel i brytare och frånskiljare med data om felorsak och livslängd. Den har också en översikt av ett fyrtiotal olika metoder för tillståndsmätningar för brytare och frånskiljare, som huvudsakligen rör de elektriska kontakterna och de mekaniska delarna. Ett system med IR sensorer har installerats på de nio kontakterna på sex frånskiljare. Målet är att minska antalet avbrott för underhåll genom att skatta skicket när frånskiljarna är i drift. De uppmätta temperaturerna tas emot genom radio och behandlas genom regression mot kvadraten av strömmen, då den bästa exponenten för strömmen visade sig vara 2,0. Förklaringsfaktorn $R^2$ är hög, över 0,9. För varje kontakt ger det en regressionskoefficient. Ju högre koefficienten är, desto mer värme utvecklas det i kontakten, vilket kan leda till skador på materialet. Koefficienterna ger en rangordning av frånskiljarna. Systemet kan också användas för att minska eller öka den tillåtna strömmen baserat på skicket. Slutligen förklaras ett ramverk för livslängdsmodellering och tillståndsmätning. Livslängdsmodellering innebär att koppla en fördelning för tiden till fel med varje delpopulation. Med tillståndsmätning avses att mäta en parameter och skatta dess värde i framtiden. Om den överskrider en tröskel, måste apparaten underhållas. Effekten av underhåll visas för fyra frånskiljare. En utveckling av riskmatrisen med osäkerheten, en sammanställning av statistik och metoder för tillståndsövervakning, ett system med IR-sensor vid kontakerna, en metod för termografiplanering och ett ramverk för livslängdsmodellering och tillståndsmätningar presenteras. De kan förbättra avbrottsplaneringen.
El suministro de energía eléctrica es importante en la sociedad moderna. Por eso los cortes eléctricos deben ser poco frecuentes y de poca duración, sobre todo en la red de transmisión. Esta tesis resume la historia del sistema eléctrico sueco. El objetivo es planificar los cortes mejor siguiendo la condición de los aparatos. La matriz de riesgo se utiliza muchas veces para escoger en qué aparatos debería realizarse mantenimiento. Esta matriz se puede mejorar añadiendo una dimensión: la incertidumbre de la probabilidad. El riesgo puede ser disminuido siguiendo cada una de las tres dimensiones: mejores mediciones, mantenimiento preventivo y mayor redundancia. El número de dimensiones puede reducirse siguiendo líneas del mismo riesgo calculadas para la distribución beta. Esta tesis presenta veinte estudios de fallos en interruptores y seccionadores con datos sobre la causa y el tiempo hasta la avería. Contiene también una visión general de cuarenta métodos para medir la condición de seccionadores e interruptores, aplicables en su mayoría a los contactos eléctricos y los componentes mecánicos. Se ha instalado un sistema con sensores infrarrojos en los seis contactos de nueve seccionadores. El objetivo es disminuir los cortes de servicio para mantenimiento, estimando la condición con el seccionador en servicio. Las temperaturas son transmitidas por radio y se hace una regresión con el cuadrado de la corriente, ya que el mejor exponente de la corriente resultó ser 2,0. $R^2$ alcanza un valor de 0,9 indicando un buen ajuste de los datos por parte del modelo. Existe un coeficiente de regresión para cada contacto y este sirve para ordenar los contactos según la necesidad de mantenimiento, ya que cuanto mayor sea el coeficiente más calor se produce en el contacto. Finalmente se explica que el modelado de tiempo hasta la avería consiste en asignar una distribución estadística a cada equipo. La monitorización del estado consiste en medir y estimar un parámetro y luego predecir su valor en el futuro. Si va a sobrepasar un cierto límite, el equipo necesitará de mantenimiento. Se presenta el efecto de mantenimiento de cuatro seccionadores. Un desarrollo de la matriz de riesgo, un conjunto de estadísticas y métodos de monitoreo de condición, un sistema de sensores IR situados cerca de los contactos, en método de planificación de termografía y un concepto para explicar la modelización de tiempo hasta la avería y de la monitorización de la condición han sido presentados y hace posible una mejor planificación de los cortes de servicio.
QC 20170928
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Hideblad, Daniel. "Equipment for Accelerated Vibration Testing." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-62587.
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The increasing complexity with the decrease in size of EEE – components (Electronic, electric and electromagnetic) raises the question on how higher energy frequencies will affect the components and their continuous development. The most common vibration testing equipment currently in use within the automotive industry and SCANIA CV AB are the electrodynamic shaker (ED system). This thesis covers the characteristics of different vibration testing equipment while analysing their strengths and weaknesses, not only for the automotive industry but also including equipment more commonly handled within the aero and space industry. The project aims to find a complement for the ED system and study the possibility for its replacement in the automotive industry.In particular, experiments are carried out and documented on a so-called “Repeatable shaker system” (RS system) for the purpose to get a better understanding on the functions of the equipment and its overall differences compared to the electrodynamic system when it comes to random vibration testing.It became clear that complementing or replacing the ED system is difficult and that the RS system work fundamentally different in comparison. Accordingly, the RS system is not a potential replacement for our purpose and it cannot perform at the same level of precision but instead is able to achieve higher energy frequencies overall, making it still ideal for its intended purposes, but not as a replacement of the ED system.
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Endo, Fumihiro, Masaki Kanamitsu, Ryo Shiomi, Hiroki Kojima, Naoki Hayakawa, and Hitoshi Okubo. "Optimization of Asset Management and Power System Operation Based on Equipment Performance." IEEE, 2008. http://hdl.handle.net/2237/11798.
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Кушвид, Леонід Віталійович, and Leonid Kushvyd. "Розробка заходів щодо надійної роботи електричного обладнання газоперекачувальної компресорної станції." Master's thesis, Тернопільський національний технічний університет імені Івана Пулюя, кафедра електричної інженерії,Тернопіль, Україна, 2020. http://elartu.tntu.edu.ua/handle/lib/33200.
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На основі обчисленої потужності 630 кВт здійснено вибір двигуна
компресора типу 4АЗМО – 630 / 60002УХЛ4 з ККД 95.7% та cos =0.88.
Здійснено розрахунок електродвигуна по нагріву та перевантаженню.
Здійснено розрахунок перерізів проводів мережі живлення та
розподільної мережі. Проведено розрахунок освітлення. Запропоновано загальну рівномірну
систему освітлення. Освітленість становить 75 лк. Як джерело світла прийнята
лампа ДРЛ потужністю 400 Вт з світловим потоком 23500 Лм. Також проведено
розрахунок аварійного освітлення.
Проведення вибір обладнання станції, а саме: автоматичні вимикачі
АП 50 для кіл керування, контактори КМВ 5211, вакуумні вимикачі
BB / TEL 10 для силових кіл.В кваліфікаційній роботі проведено обчислення потужності та здійснення вибору двигуна компресора, запропоновані зміни в схемі керування компресором, проведено розрахунок електродвигуна по нагріву та перевантаженню, здійснено розрахунок освітлення, проведена оцінка зорових робіт, здійснено вибір системи освітлення та джерел світла, здійснено розміщення світильників та вибір їх типу, а також вибір ламп, пораховано аварійне освітлення приміщення, здійснено розрахунок освітлення точковим методом, проведена перевірка заземлення на установці. Також проведено вибір апаратури, вибір перерізу проводів кабелів живлення, здійснено опис спроектованої схеми керування, розглянуто захист виробничого цеху
In the qualification work the calculation of power and selection of the compressor motor is carried out, changes in the control scheme of the compressor are offered, the electric motor on heating and overload is calculated, lighting is calculated, visual works are estimated, lighting system and light sources are selected, lamps are placed and selected. type, as well as the choice of lamps, the emergency lighting of the room is calculated, the calculation of spot lighting is performed, the grounding check on the installation is carried out. Also the choice of the equipment, the choice of section of wires of power cables is carried out, the description of the designed control scheme is carried out, protection of production shop is considered
ЗМІСТ ВСТУП...6 1 АНАЛІТИЧНИЙ РОЗДІЛ...8 1.1 Автоматизація технологічних енергоустановок для ефективного транспорту газу...8 1.2 Автоматизація електроприводних газоперекачувальних агрегатів 11 1.3 Апарати повітряного охолодження газу із стабільною вихідною температурою...13 1.4 Висновки до розділу...19 2 РОЗРАХУНКОВО-ДОСЛІДНИЦЬКИЙ РОЗДІЛ...20 2.1 Обчислення потужності та здійснення вибору електродвигуна компресора...20 2.2 Зміни в схемі керування компресором...21 2.3 Розрахунок електродвигуна по нагріву та перевантаженню...22 2.4 Розрахунок освітлення...24 2.5 Оцінка зорових робіт...25 2.6 Вибір системи освітлення та джерел світла...26 2.7 Розміщення світильників та вибір їх типу...27 2.8 Вибір ламп...29 2.9 Схема живлення, вибір типу щитків...30 2.10 Перерізи мережі живлення та розподільної мережі...33 2.11 Аварійне освітлення приміщення...35 2.12 Розрахунок освітлення точковим методом...37 2.13 Перевірка заземлення на установці...39 2.14 Висновки до розділу...3 ПРОЕКТНО-КОНСТРУКТОРСЬКИЙ РОЗДІЛ...43 3.1 Вибір обладнання...43 3.2 Вибір перерізу проводів кабелів живлення...45 3.3 Опис спроектованої схеми керування...45 3.4 Захист виробничого цеху...48 3.5 Принципова схема управління електродвигуном компресора. Управління релейним захистом...48 3.5.1 Принцип дії схеми управління...48 3.5.2 Вибір апаратів для схеми управління...50 3.6 Висновки до розділу..54 4 ОХОРОНА ПРАЦІ ТА БЕЗПЕКА В НАДЗВИЧАЙНИХ СИТУАЦІЯХ...55 4.1 Захисне відключення...55 4.2 Організаційні заходи щодо попередження електротравм...56 4.3 Забезпечення оповіщення персоналу та населення у разі виникнення аварій на потенційно небезпечних об’єктах...59 4.4 Джерела виникнення та уражаюча дія електромагнітного імпульсу...60 ЗАГАЛЬНІ ВИСНОВКИ...63 ПЕРЕЛІК ПОСИЛАНЬ...64 ДОДАТКИ...1 Додаток А. Захист виробничого цеху...2
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Постол, Л. М. "Проект модернізації ВРП-110 кВ підстанції 330 кВ "Суми північна". Вибір первинного та вторинного обладнання." Master's thesis, Сумський державний університет, 2018. http://essuir.sumdu.edu.ua/handle/123456789/71487.
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Наведено характеристики об'єкту реконструкції, приведені техніко-економічні обґрунтування необхідності реконструкції об’єкту, виконаний аналіз варіантів реконструкції, виконано розрахунок електричних параметрів аварійних режимів, зроблений вибір силового и вторинного обладнання, виконано розрахунок економічної ефективності, Визначені параметри для проектування систем АСОЕ, АСУ ТП, АСКПЯЕ. В результаті проектування визначена головна схема ВРП 110 кВ.
Виконаний розрахунок струмів короткого замикання на шинах 110кВ та лініях приєднань. Проведений аналіз характеристик та вибір силового обладнання (комутаційних апаратів, шинних струмопроводів, вимірювальних трансформаторів тощо). Проведений аналіз характеристик та вибір пристроїв РЗА та ПА. Виконане технічне завдання на проектування АСУ ТП диспетчеризацій та автоматизації перемикань на ВРП 110кВ. Виконане технічне завдання на проектування автоматизованих систем обліку та контролю параметрів якості електроенергії. Проаналізована економічна ефективність реконструкції та визначений термін окупності проекту. Проаналізована система заходу від дії електроструму, а також
визначені критерії перевірки стану безпеки за видами електроустановок.
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Бартків, Андрій Степанович, and Andriy Bartkiv. "Дослідження надійності пристроїв релейного захисту на лініях 110/10(6) кВ." Master's thesis, ТНТУ імені Івана Пулюя, 2019. http://elartu.tntu.edu.ua/handle/lib/29658.
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У дипломній роботі проведено модернізацію трансформаторної підстанції 110/35/10 кВ з використанням мікропроцесорних пристроїв релейного захисту для забезпечення надійності й ефективності постачання електроенергії споживачам. Досліджена модель надійності пристроїв релейного захисту як результат визначення ймовірностей відмов їх схем в певні моменти часу, а також на інтервалі часу. Досліджена модель коефіцієнта передачі електромагнітного трансформатора струму як елемента кола релейного захисту і встановлено необхідний динамічний діапазон лінійного перетворення первинного струму без спотворень й робочий частотний діапазон перетворювача. Проведена заміна короткозамикачів на стороні 110 кВ на елегазові вимикачі, оливних вимикачів на стороні 35 кВ на вакуумні, а також здійснений вибір трансформаторів струму і напруги та іншого комутаційного обладнання. Виконаний розрахунок струмів короткого замикання кіл навантажень 110/35/10 кВ, на основі яких здійснено вибір захисного обладнання.In this diploma paper the modernization of the 110/35/10 kV transformer substation using microprocessor relay protection devices to ensure the reliability and efficiency of electricity supply to consumers has been carried out. The reliability model of the relay protection devices as a result of determining the probability of failure their circuits at certain points in time, as well as at the time interval, has been researched. The model of the transmission ratio of the electromagnetic current transformer as an element of the relay protection circuit has been investigated. The required dynamic range of linear conversion of the primary current without distortion and the operating frequency range of the converter was set. The 110 kV short circuits by the 35 kV gas switches and the vacuum switches on the vacuum switches were replaced. The choice of current and voltage transformers and other switching equipments was made. The calculation of short circuits currents of 110/35/10 kV loads, on the basis of which the choice of protective equipment are executed.
ВСТУП ……………………………………………………………………… 9 1 АНАЛІТИЧНА ЧАСТИНА .......………………………………………….. 13 1.1 Аналіз електричного господарства трансформаторної підстанції 110 кВ ................................................................................................. 13 1.2 Аналіз технічного стану комутаційного обладнання ПС 110/35/10 кВ ................................................................................ 14 1.3 Обґрунтування заміни оливних вимикачів на вакуумні чи елегазові ............................................................................................. 15 1.4 Переваги вакуумних вимикачів ....................................................... 15 1.5 Переваги елегазових вимикачів ....................................................... 15 1.6 Аналіз електропостачання міста Тернополя ................................... 16 1.7 Аналіз потужності режимів і ефективності функціонування ПС 110 кВ .......................................................................................... 17 1.8 Аналіз мікропроцесорних пристроїв релейного захисту. Їх особливості, переваги і недоліки ................................................ 20 1.9 Аналіз причин низької функціональної надійності мікропроцесорних пристроїв релейного захисту .......................... 21 1.10 Мікропроцесорний захист, який використовується для захисту трансформаторів і автотрансформаторів ........................................ 23 1.11 Висновки до розділу ....................................................................... 26 2 НАУКОВО–ДОСЛІДНА ЧАСТИНА .......……………………………….. 28 Дослідження надійності мікропроцесорних пристроїв релейного захисту та вимог до цифрових первинних перетворювачів ......... 28 2.1 Проблеми оцінювання надійності релейного захисту .................. 28 2.2 Порівняльний аналіз надійності схем релейного захисту ............................................................................................... 32 2.3 Релейний захист нового покоління. Вимоги до цифрових первинних перетворювачів сигналів ........................................…... 35 2.4 Висновки до розділу ……..........................................……………... 41 3 ТЕХНОЛОГІЧНА ЧАСТИНА …………......…………………………….. 42 3.1 Вибір вимикачів .....................................................………………… 42 3.2 Вибір роз’єднувачів .......................................................................... 46 3.3 Вибір вимірювальних трансформаторів струму і трансформаторів напруги ................................................................ 48 3.4 Вибір струмоведучих частин ........................................................... 54 3.5 Вибір конструкції розподільного пристрою ...............…………... 56 3.6 Вибір трансформатора власних потреб .......................................... 56 3.7 Вибір запобіжників та автоматичних вимикачів .....................….. 57 3.8 Вибір обмежувачів перенапруги 10 кВ ........................................... 59 3.9 Висновки до розділу ....................................................................... 61 4 ПРОЕКТНО–КОНСТРУКТОРСЬКА ЧАСТИНА ……………….......….. 62 Розрахунок струмів короткого замикання на дільницях електромережі трансформаторної підстанції та режимів навантажень ....................................................................................... 62 4.1 Початкові дані для розрахунку струмів короткого замикання ..... 63 4.2 Розрахунок струмів короткого замикання в точці К-1 .................. 64 4.3 Розрахунок струмів короткого замикання в точці К-2 ..............… 71 4.4 Розрахунок струмів короткого замикання в точці К-3 .................. 75 4.5 Регулювання напруги трансформаторною підстанцією 110/35/10 кВ ....................................................................................... 79 4.6 Розрахунок штучного заземлення ПС 110/35/10 кВ ...................... 80 4.7 Розрахунок блискавкозахисту ПС 110/35/10 кВ ........................... 84 4.8 Висновки до розділу .....................................……………………… 87 5 СПЕЦІАЛЬНА ЧАСТИНА …………….......…………………………….. 88 5.1 Вибір і розрахунок мікропроцесорного релейного захисту трансформатора .......................................................................…… 88 5.2 Конфігурація мікропроцесорного терміналу типу БЭ2704 V041 ............................................................................. 90 5.3 Розрахунок диференційного захисту трансформатора ................. 91 5.4 Розрахунок максимального струмового захисту з блокуванням по напрузі .......................................................................................... 96 5.5 Вибір уставок пристрою резервування відмови вимикача ........... 102 5.6 Розрахунок захисту від перевантаження ........................................ 102 5.7 Розрахунок блокування пристрою регулювання під напругою ... 103 5.8 Розрахунок захисту від перегрівання ............................................. 104 5.9 Газовий захист ................................................................................... 104 5.10 Газовий захист перемикача пристрою регулювання під напругою ............................................................................................ 105 5.11 Висновки до розділу ....................................................................... 105 6 ОБҐРУНТУВАННЯ ЕКОНОМІЧНОЇ ЕФЕКТИВНОСТІ ….....……….. 106 6.1 Методика оцінки економічної ефективності інженерних рішень ................................................................................................ 106 6.2 Ступінь деталізації розрахунків економічної ефективності ......... 112 7 ОХОРОНА ПРАЦІ ТА БЕЗПЕКА В НАДЗВИЧАЙНИХ СИТУАЦІЯХ …....................................................................………………... 113 7.1 Аналіз небезпечних факторів на трансформаторній підстанції та розробка заходів щодо їх зниження ................................................ 113 7.2 Заходи пожежної безпеки на трансформаторній підстанції ......... 114 7.3 Організаційні заходи захисту персоналу підстанції ...................... 115 7.4 Організація цивільного захисту на об’єктах електроенергетики ............................................................................ 116 7.5 Роль місцевого управління у створенні безпекового середовища життєдіяльності людей ..................................................................... 117 8 ЕКОЛОГІЯ …………………….......………………………………………. 119 8.1 Необхідність дотримання екологічного балансу біосфери .......... 120 8.2 Створення локальних енергетичних систем для мінімізації впливу на біосферу ........................................................................... 121 ЗАГАЛЬНІ ВИСНОВКИ ДО ДИПЛОМНОЇ РОБОТИ ….......…………… 123 ПЕРЕЛІК ПОСИЛАНЬ ………………….......……………………………… 125
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Mynář, Josef. "Vliv frekvenčního měniče na životnost ložisek a jejich poškození." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-378018.
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The diploma thesis deals with the technical diagnostics of machines with a closer focus on vibrational diagnostics. In the thesis is elaborated a design of a diagnostic system with measurement methodology, measurement procedure and evaluation of measured data on the machine produced by Siemens.
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PALOMARES, ROSARIO DEL PILAR ALVA. "METROLOGICAL RELIABILITY OF HIGH FREQUENCY SURGICAL EQUIPMENT." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2005. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=8010@1.
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FINANCIADORA DE ESTUDOS E PROJETOSMINISTÉRIO DA CIÊNCIA E TECNOLOGIA
A garantia da confiabilidade metrológica de equipamentos médicohospitalares, apesar de essencial para garantir a obtenção do efeito desejado e evitar efeitos adversos, em geral não é realizada durante o período de uso (pós-comercialização). Dentre as principais causas possíveis desta realidade se encontra a falta de informação por parte dos profissionais usuários quanto aos riscos, ou seja, a reduzida cultura metrológica no ambiente da saúde. A partir da identificação de alguns pontos vulneráveis e de graves repercussões na utilização inadequada de bisturis eletrônicos, esta dissertação avaliou parâmetros para a confiabilidade metrológica destes equipamentos, tanto em nível técnico e normativo, quanto em termos da utilização em ambientes hospitalar.Foi realizada uma busca e identificação da normalização nacional, e avaliada a abrangência das normas para garantir de forma completa a utilização dos equipamentos. Os trabalhos práticos para a avaliação metrológica das unidades eletrocirúrgicas foram realizados em três hospitais. Os resultados obtidos auxiliaram na avaliação da confiabilidade metrológica das unidades eletrocirúrgicas em uso, apontando para a necessidade não só de um controle metrológico periódico, como também da inserção de parâmetros de avaliação que não constam na norma aplicável ao equipamento em estudo. Parte desta dissertação foi financiada, através do Convênio referência FINEP n° 22.01.0692.00, pelo Programa Tecnologia Industrial Básica e Serviços Tecnológicos para a Inovação e Competitividade MCT/FINEP/FNDCT/Fundo Verde Amarelo, um programa cooperativo universidade-empresa.
The metrological reliability of electromedical equipment, although essential in order to guarantee the desired effects and to avoid adverse effects, is often not verified after the equipment is sold and being used (post-sale period). This is partially due to the fact that, usually, health-care takers that use the equipment are unaware of the risks involved, in other words, there is a low metrological culture in the healthcare environment. In this dissertation, vulnerable aspects regarding the inadequate use of high frequency surgical equipment, also known as electrosurgical unit (ESU), were identified, and their consequences evaluated. Based on these results, technical and standard parameters important for the metrological reliability of ESUs, were evaluated. This dissertation also includes a detailed bibliographical research of basic principles, technical specifications, and international procedures that guarantee the metrological reliability of electrosurgical units. The scope of national standards was evaluated in order to guarantee the correct use of all of the ESU´s functions and modes. Experimental data for the metrological evaluation of the EUSs were collected in three (3) hospitals, one (1) private and two (2) public. The results are helpful for evaluating their metrological reliability, and indicate that not only that there is a need for a periodical metrological evaluation, but also that other parameters should be included in existing standards. Part of this dissertation was financed by the Convênio referência FINEP n° 22.01.0692.00 of the Programa Tecnologia Industrial Básica e Serviços Tecnológicos para a Inovação e Competitividade MCT/FINEP/FNDCT/Fundo Verde Amarelo, a universitycompany cooperative program.
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Steel, Donald. "Software reliability prediction." Thesis, Abertay University, 1990. https://rke.abertay.ac.uk/en/studentTheses/4613ff72-9650-4fa1-95d1-1a9b7b772ee4.
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The aim of the work described in this thesis was to improve NCR's decision making process for progressing software products through the development cycle. The first chapter briefly describes the software development process at NCR, detailing documentation review and software testing techniques. The objectives and reasons for investigating software reliability models as a tool in the decision making process are outlined. There follows a short review of software reliability models, with the Littlewood and Verrall Bayesian model considered in detail. The difficulties in using this model to obtain estimates for model parameters and time to next failure are described. These estimation difficulties exist using the model on good datasets, in this case simulated failure data, and the difficulties are compounded when used with real failure data. The problems of collecting and recording failure data are outlined, highlighting the inadequacies of these collected data, and real failure data are analysed. Software reliability models are used in an attempt to quantify the reliability of real software products. The thesis concludes by summarising the problems encountered when using reliability models to measure software products and suggests future research into metrics that are required in this area of software engineering.
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Qamber, I. S. H. "Markov modelling of equipment behaviour." Thesis, University of Bradford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381011.
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Hinds, Peter Alan. "Reliability assessment for future military land systems." Thesis, University of Exeter, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364421.
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Hammal, Redouane. "Décharges partielles dans les condensateurs tout-film imprégnés." Université Joseph Fourier (Grenoble), 1998. http://www.theses.fr/1998GRE10006.
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Les decharges partielles ont ete mesurees sur des modeles de condensateurs tout-film dont le dielectrique est du polypropylene (pp) impregne. Ces cellules ont ete alimentees en haute tension alternative. L'influence de l'epaisseur de dielectrique ou des armatures ainsi que les effets de la temperature et du vieillissement ont ete examines. Les representations n() et q#m#o#y() du nombre et de l'amplitude des decharges dans la phase de la tension alternative servent a caracteriser la source de ces decharges : decharges en bord d'armature dans un modele de condensateur sans defaut ou decharges generees par des defauts artificiellement introduits dans la cellule d'etude (defaut d'impregnation, defaut de contact, cavite dans un film de pp, film de pp plie). Le but de cette caracterisation est la constitution d'une base de donnees qui servira a la reconnaissance de la source des decharges sur des appareils industriels et permettra d'estimer la duree de vie de ces appareils. Les tensions d'apparition et d'extinction des decharges partielles (tadp et tedp), l'evolution des decharges en fonction du temps ou de la tension appliquee sont des elements qui servent a la caracterisation des decharges. Cette tache se fait egalement au moyen de parametres calcules a partir des distributions n() et q#m#o#y(). Ces parametres peuvent etre les moments d'ordre 3 et 4 ou bien les parametres que nous avons introduits dans cette etude et qui sont les parametres de position et le parametre d'efficacite energetique. Ces deux derniers parametres sont les plus efficaces car ils permettent a eux seuls de differencier la plupart des cas etudies.
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Zhu, Q. S. "Precision electrical impedance tomography instrumentation." Thesis, Oxford Brookes University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332494.
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DRUMMOND, ALINE MARIA DE CARVALHO. "METROLOGICAL RELIABILITY OF LASER AND INTENSE PULSED LIGHT ELECTROMEDICAL EQUIPMENT." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2007. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=10706@1.
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CENTRO TECNOLÓGICO DO EXÉRCITOPara lançar equipamentos eletromédicos no mercado brasileiro, é necessária a obtenção de registro da Agência Nacional de Vigilância Sanitária, que tem por requisito a apresentação da certificação de conformidade. Na presente dissertação foram realizados estudos dos documentos normativos necessários para a avaliação da conformidade de equipamentos a laser e Luz Intensa Pulsada (IPL) para uso terapêutico, visando a análise da abrangência das normas para a garantia da confiabilidade metrológica de tais equipamentos biomédicos. Os equipamentos terapêuticos a laser precisam estar em conformidade com a Norma Geral NBR IEC 601-1, colaterais e com a Norma Particular NBR IEC 601- 2-22. O IPL, por sua vez, consiste em instrumentação óptica para uso terapêutico que não é referida na Norma Particular NBR IEC 601-2-22 e ainda não possui norma técnica específica. Verificou-se ao longo dos trabalhos para esta dissertação que, apesar da norma particular NBR IEC 601-2-22 prescrever a necessidade da medição de energia, no Brasil não existem padrões rastreáveis para calibração de medidor de energia laser. Também foi identificada a necessidade da inclusão na norma particular a avaliação das seguintes grandezas para os equipamentos a laser: divergência do feixe, duração do pulso, diâmetro do feixe de trabalho, taxa de repetição de pulso, e definição do limite máximo para o diâmetro do feixe de trabalho. Além disso, embora a norma particular não inclua os equipamentos IPL em seu escopo, esta poderia ser ampliada para adaptar-se também à avaliação deste equipamento. Para tanto, além das grandezas mencionadas acima, sugeridas para a avaliação dos equipamentos a laser, seria necessária também a avaliação de filtros que limitam os comprimentos de onda de emissão da radiação. Concluiuse também que, como a norma particular estudada recomenda o atendimento a várias cláusulas de norma não incorporada no Brasil pela ABNT - a IEC 60825-1 - cujo conteúdo é exigido para a avaliação da conformidade do equipamento, recomenda-se a complementação da norma nacional com a informação contida na IEC 60825-1. Além da inclusão de itens ao documento normativo, o presente trabalho recomenda a avaliação da incerteza da medição não somente para constar nos documentos acompanhantes, como também na avaliação de conformidade do produto. Também considerando a tolerância descrita na norma de 20% de erro da saída laser, e considerando desde já evidências apresentadas no trabalho indicando que é excessiva, recomendou-se um estudo detalhado objetivando, a partir da análise das diferentes aplicações biomédicas dos equipamentos, melhor definição de tal tolerância. Discute-se ainda sobre a importância da avaliação periódica durante o tempo de sua utilização clínica, para garantia da confiabilidade também ao longo da vida útil destes equipamentos.
Manufacturers must present a Conformity Certificate and register electrical medical products with the National Health Vigilance Agency (ANVISA) before releasing them in the Brazilian market. For medical laser equipment, the mandatory standards are the general safety standard for medical electrical equipment (NBR IEC 601-1) and the particular safety standard for diagnostic and therapeutic laser equipment (NBR IEC 601-2-22). Despite not having a particular standard with safety requirements, medical IPL equipment used for therapeutic applications are also required by ANVISA to comply with NBR IEC 601-1 and NBR IEC 601-2-22. In this thesis, the standards used for the conformity evaluation of laser and intense pulsed light (IPL) electromedical equipment were examined with the purpose of assessing their effectiveness regarding metrological reliability. It was found that, despite the energy measurement requirements in the particular standard NBR IEC 601-2-22, there are no traceable standards for optical energy measurements in Brazil. It was also found that the measurement of other quantities (such as, beam divergence and diameter, pulse duration, pulse repetition rate, among others) should be included in the particular standard. Additionally, it was found that, in order to evaluate safety requirements for medical IPL equipment, the particular standard should include requirements concerning the filters that limit the bandwidth of the radiation. In addition to including the parameters mentioned above, this dissertation also recommends the inclusion of the uncertainty in measurement not only in accompanying documents, but also in the conformity evaluation of the product. Moreover, based on evidences, discussed in this thesis, that the current acceptable error of 20% for the laser power output is extremely high, an in-depth evaluation of the actual acceptable error is recommended. Furthermore, since the particular safety standard (NBR IEC 601-2-22) refers to several clauses in the IEC 60825-1 standard, which has not yet been adopted in Brazil, it is recommended that either the IEC 60825-1 standard be adopted in Brazil, or that the clauses mentioned in NBR IEC 601-2-22 be incorporated to it. Finally, the importance of periodic postsale verifications of electromedical equipment in order to ensure metrological reliability is also discussed.
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Fenlon, Teresa Jayne. "Medical applications of electrical impedance measurements." Thesis, University of Surrey, 1992. http://epubs.surrey.ac.uk/773022/.
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The utilisation of electrical impedance measurements within the medical profession has broadened greatly since the advent of blood flow analysis in the 1950s. This thesis considers some of the important electrical impedance measurements currently used at a research stage in medicine, with specific emphasis on three major application. These are: the analysis of human body composition, particularly the quantification of body fat, the analysis of gastric motility using electrical impedance epigastrography and electrical impedance tomographic imaging of the abdomen in order to monitor gastric motility.
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Шевченко, Валентина Владимировна, Алла Викторовна Дон, and Татьяна Геннадиевна Кононова. "Проблемы современной электроэнергетики, пути ее развития и оценка источников электроэнергии." Thesis, Accent Graphics Communications & Publishing, Canada, 2019. http://repository.kpi.kharkov.ua/handle/KhPI-Press/46945.
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Losik, Len. "How to Use Analog Telemetry to Produce Equipment with 100% Reliability." International Foundation for Telemetering, 2010. http://hdl.handle.net/10150/605961.
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ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, CaliforniaEquipment reliability is driven by infant mortality failures, which can be eliminated using a prognostic analysis prior, during and/or after the exhaustive and comprehensive dynamic environmental factory acceptance testing which conducted to increase equipment reliability by identifying equipment that fails during test for repair/replacement. To move to the 100% reliability domain, equipment dynamic environmental factory testing should be followed by a prognostic analysis to identify the equipment that will fail within the first year of use. During all equipment testing, only equipment functional performance is measured and equipment performance is unrelated to short-term or long-term equipment reliability making testing alone inadequate to produce equipment with 100% reliability. A prognostic analysis converts performance measurements to reliability measurements invasively by sharing test data used to measure equipment performance. Performance data that is converted to reliability data provides a time-to-failure (TTF) in minutes/hours/days/months for equipment that will fail within the first year of use, allowing the production of equipment with 100% reliability, decreasing risk and making getting to space safe and reliable.
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Thouin, Frédéric. "Video-on-demand equipment allocation." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=99545.
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Network-based video-on-demand (VoD) deployments are today very limited in scope. The largest deployed libraries are just 0.7% of the global movie and TV-series catalog and peak utilization of VoD targets are 10--15% of broadcast TV peak viewing numbers. Recognizing that libraries and usage may grow, service providers are intensely interested in large-scale content delivery networks that provide content propagation, storage, streaming, and transport. We focus on one of the challenges of VoD network design: resource planning. We describe a method and design tool for the planning of large-scale VoD systems and address the resource allocation problem of determining the number and model of VoD servers to install in a, topology such that the deployment cost is minimized. Our general design tool provides important feedback and insights on VoD network design; we observed that the available equipment and the topology had a significant impact on the resulting design.
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Saranga, Haritha. "Relevant condition parameter based approach to reliability and maintenance." Thesis, University of Exeter, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323982.
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Dash, Ishita. "Provision of Reliability Data for New Technology Equipment in Subsea Production Systems." Thesis, Norges Teknisk-Naturvitenskaplige Universitet, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-21114.
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For certain new technologies such as subsea processing systems reliability, compactness and easy maintainability are the most important factors to be considered while designing. This is because installation and retrieval costs increase with the increase in the size of the equipment. Failure of such equipments will cause huge production losses leading to enormous financial losses.However to have a better understanding of how reliable a component is, it is most appropriate to express it quantitatively. Methods to predict the reliability of equipment have been suggested however they all require historical data to be fed as input to conduct the analysis. When dealing with new technologies these historical datas are nearly absent.The objective of this thesis is to propose a method for estimating the failure rate of such new technologies with special focus on subsea processing systems. A literature study was carried out on the various reliability datas such as OREDA, MIL-HDBK-217, FIDES and NSWC. The key features of each of the reliability data handbooks were identified. Also the various methods used for estimating the failure rates were discussed especially for FIDES and NSWC. A literature review of the various subsea processing systems was also carried out and a final focus was made on subsea multiphase helico-axial pump. A bayesian approach was chosen for the new proposed approach. The suggested approach consists of six steps where the analysis starts with a failure mode and effect analysis of the chosen new technology, helico-axial subsea pump in our case. Using the results from the failure mode and effect analysis and literature reviews an influence diagram is developed for the helico-axial pump. The probabilities of the priors and the conditional probabilities are assigned based reliability data handbooks and literature reviews. The importance of each of the failure modes is identified. Finally the failure of the pump is calculated by multiplying the failure rate of each of the failure modes with its calculated importance. The total failure rate of the pump is obtained by adding the modified failure rates. Using this method it was seen that the failure rate of the helico-axial pump with the given current design has a failure rate which is less than that of a centrifugal pump which is required to operate for a period of six years with one failure. Finally recommendations for further work have also been included at the final part of this report.
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Hall, Robert A. "Reliability analysis and discrete event simulation as tools for mining equipment management." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0035/NQ52824.pdf.
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Parreira, Sílvia da Conceição Espada Chainho Parreira. "Hazard models applied to industrial equipment using reliability distributions and RCM Implementation." Doctoral thesis, Universidade de Évora, 2020. http://hdl.handle.net/10174/29825.
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Statistical methods are nowadays being increasingly useful in industrial engineering. From plant
design reliability to equipment analysis, there is much to cover with statistical models in order to improve
efficiency of the systems. A real challenge is put forward to maintenance managers due to high requirements
demand in this competitive world where changes come fast and a good support in decision is then essential,
which leads us to the Reliability Centered Management (RCM) philosophy, that guides institutions in a
reliability sense of option. The present work refers to a PhD made within a business context, namely, industrial context, aiming to be practical and fulfil the needs of Sines’ refinery concerning RCM requirements.
A non-controlled environment was at stake, once real data was collected and no possibility to follow and
focus on a certain subject was possible, against traditionally theoretical models with produced data usually
used for this kind of studies. For this purpose, a collection of real failure data for rotating equipment served
as support to statistical analysis using survival statistical models, which are most of times used in medicine
or biology, but are being increasingly used in engineering. Survival models with random components as well
as mixtures of two distributions were used and a collection of reliability data was constructed for rotating
equipment. In this kind of industry, impact of failure rates is financially measured, especially insurance
related, as a higher reliability of systems usually implies lower insurance rates. Our goal was to contribute to
a reliability databook compilation so they could be able to benchmark with standards of the same industry
type, as OREDA (2009), which results have been effective.
The main innovative aspect was concerned to the root cause analysis for Turbo-Expander (TE) turbine to have shutdowns due to vibration. Beyond its large economic impact, this equipment is quite rare
within its configuration and that is the reason why it is very special. Despite there already exist some
studies about TE vibration causes, chemical and mechanical related, we’ve tried to understand TE failure
problem using parametric survival models, using physical and mechanical variables involved in the process.
Even though no absolute conclusion was found, results match and reinforce previous studies on the subject
and highlight that composition of the feedstock is highly related with TE vibration; RESUMO: Modelos de risco aplicados a equipamento industrial utilizando distribuições de
fiabilidade e implementação de RCM
Os métodos estatísticos são cada vez mais úteis na engenharia industrial. Desde o desenho de base
até à fiabilidade de equipamentos, há muito a cobrir com os modelos estatísticos de forma a aumentar
a eficiência dos sistemas. Um verdadeiro desafio é então colocado à gestão de manutenção devido aos
elevados requisitos necessários e normas a cumprir, neste mundo competitivo onde as mundanças aconteçem rápido e um bom suporte à decisão é absolutamente necessário. Isto leva-nos à filosofia do RCM
(Reliability Centered Management), a qual guia as empresas no sentido da gestão pela fiabilidade. O presente trabalho refere-se a um doutoramento realizado em contexto empresarial/industrial com um sentido
prático e de resposta a questões colocadas pela refinaria de Sines no que respeita à gestão pela fiabilidade.
Em jogo estava um ambiente não controlado e dados reais ao contrário do que é habitual num projecto
desta natureza, com dados simulados. Uma primeira parte deste estudo foi realizada com base em dados
de equipamento rotativo da refinaria de Sines e serviu de base ao nosso estudo estatístico que se centrou
nos modelos de sobrevivência, muitas vezes utilizados em medicina ou biologia, e que são cada vez mais
utilizados em engenharia. Modelos de sobrevivência com componentes aleatórias ou modelos com mistura
de duas distribuições, são alguns exemplos dos modelos utilizados. Contribuir para a construção de uma
compilação de dados de fiabilidade era o nosso objectivo, de forma a que a refinaria pudesse ter a possibilidade de realizar benchmarking com indústrias do mesmo tipo, como é o caso do OREDA (2009).
O principal aspecto inovador deste trabalho está relacionado um equipamento raro na sua configuração, o Turbo-Expander, cujas vibrações elevadas levam a paragens intempestivas. O elevado impacto
económico deste problema é motivo para que vários artigos sobre o tema já tenham sido escritos, quer
relacionados com váriáveis físicas como químicas ou processuais. Apesar de não existir um absoluto resultado concreto, o nosso trabalho permitiu reforçar os estudos já existentes sobre o problema e realçar a
importância da composição da matéria-prima, com forte probabilidade de produzir componentes capazes
de levar a elevadas vibrações.
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Villanueva, Anita A. (Anita Ariel) 1978. "Electrical reliability of RF power GaAs PHEMTs." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/87862.
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Al-Saadi, S. "Development of a reliability and metrology assessment methodology : maintenance data from the GMC Fire Service for fire fighting vehicles and appliances are analysed to assess reliability performance and to determine relationships between engineering metrology, reliability and quality assurance aspects." Thesis, University of Bradford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264585.
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Syed, Tariq. "Automated test system for ADSL equipment." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ58510.pdf.
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Bentil, Joseph Kingsley Attom. "Improving Buffalo City's sub-transmission reliability." Master's thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/23388.
Full textAbstract:
Several experiences of sudden large scale disruptions in electrical service deeply impacted both social stability and economic development in affected communities and caused lower levels of reliability performance. The prevention of such catastrophic incidents poses huge challenges for reliability study and operational practices in Buffalo City's sub-transmission network. Primarily investigations on the field shows, aging infrastructure, relay failures and reactive maintenance practice is eminent. Inspired by these challenges, this dissertation proposes an analysis of the critical transition in sub-transmission network from a lower level of reliability to an economically and acceptable level of reliability. The transition of the operational "stress" and its large scale of power interruptions are studied. The transition of the existing sub-transmission to the alternative sub-transmission models has been presented. The analysis of load flow and fault level calculations identifies the loading trends critical to cause operational "pressure" of unplanned interruptions. The results in this research work had to discover the most appropriate resolutions to aging equipment, reactive maintenance and protection systems. The DIgSILENT Power Factory simulates and quantifies the results of the problems that could occur in the sub-transmission network in the immediate future. Measures to mitigate any occurrence which might cause more prone to a catastrophic blackout are presented. The proposed corrective measures of upkeep aging infrastructure, relay responsiveness and planned preventative maintenance have been recommended. The development of these corrective measures and the proposed network model is the key to reaching higher levels of reliability performance in the energy supply that communities require in Buffalo City Metropolitan Municipality.
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Du, Junrong. "Evaluation of equipment reliability, availability and maintainability in an oil sands processing plant." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/7527.
Full textAbstract:
The oil sands industry is a developing sector of Canada’s economy; one area of focus for
oil sands companies is to improve plant maintenance and overall plant availability.
Although considerable progress has been made in the improvement of plant maintenance
in other industries, oil sands and mining companies in general do not significantly benefit
from this due to variable feed supply that impacts plant performance. As well historically
for mining maintenance has not been done well.
The work presented in this thesis develops a framework for understanding oil sands
processing plant key equipment failures by utilizing data collected over two years at
Albian Sands Energy Inc, an operator of an oil sands mine in Alberta, Canada. The data
is used to calculate mean time between maintenance for key pieces of oils sand
processing equipment. As well various statistical techniques are applied to the data to
identify the best maintenance strategies for the site. Finally the efficacy of advanced
statistical techniques, such as Power Law modeling, for predicting time to next failure for
equipment is demonstrated.
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Lee, Sung Keun. "Modelling the reliability of critical ship equipment subject to at sea inspection maintenance." Thesis, University of Salford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335556.
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Mangs, Johan. "On the fire dynamics of vehicles and electrical equipment /." Espoo [Finland] : VTT Technical Research Centre of Finland, 2004. http://www.vtt.fi/inf/pdf/publications/2004/P521.pdf.
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Benassi, Andrea. "Modeling of Conductors in Electrical Equipment & Sensitivity Studies." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amslaurea.unibo.it/955/.
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Oka, Ashok A. "Reliability and restoration algorithms for electrical distribution systems." Diss., This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-08232007-111001/.
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Liu, Chi-Chao. "A comparison between the Weibull and lognormal models used to analyse reliability data." Thesis, University of Nottingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362886.
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Holman, Jason (Jason William) 1974. "Optical networking equipment manufacturing." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/44603.
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Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science; in conjunction with the Leaders for Manufacturing Program at MIT, 2001.Includes bibliographical references (leaf 70).
Celestica, a global contract manufacturer specializing in printed circuit board assembly and computer assembly, has recently begun manufacturing equipment for the optical networking equipment (ONE) industry. The expansion to include ONE manufacturing requires the development of new skills in handling optical fiber and components, a new supply chain strategy, and a new approach to manufacturing systems control. Celestica is developing a set of standards for ONE manufacturing that will support the rapid development of the new skills required for this industry. This work outlines the standards and explores the specific issues related to manufacturing with optical fiber, including the mechanical reliability and optical performance of various types of optical fibers. An overview of the telecommunications industry is provided, including an analysis of its supply chain structure. Observations are made on trends in the industry and the ways that these trends have affected Celestica in the past, and could impact Celestica in the future. Finally, Celestica's current approach to manufacturing systems control is evaluated, and suggestions are made for improving systems control and project management when manufacturing for such a rapidly evolving industry.
by Jason Holman.
S.M.
M.B.A.
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Alizadeh, Siamak. "Reliability assessment of safety instrumented systems subject to process demand." Thesis, University of Aberdeen, 2018. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=237653.
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Industry and society are now aware of risk more than ever before. Organisations whose activities pose risk to individuals and society are accountable to manage and reduce risk to an acceptable level. In this regard, utilisation of Safety Instrumented Systems (SISs) as an independent protection layer is a practical method of achieving the required risk reduction. The role of a SIS is to maintain the safety of equipment under control by providing a safety-related function. The International Standards, IEC 61508/61511, provide a set of guidelines to promote consistency for implementation of SISs used for risk reduction. In accordance with IEC 61508, the performance of a SIS shall be established by computing the associated Probability of Failure on Demand (PFD) as a reliability measure using a suitable technique. The principal purpose of this research is to provide the basis for reliability assessment of redundant SISs affected by process demand as well as component failures. This dissertation introduces four new reliability models for redundant SISs subject to process demand for the first time using Markov analysis technique. The proposed reliability models 1 and 3 incorporates process demands in conjunction with Common Cause Failure (CCF) and evaluates their impacts on the reliability quantification of 1oo2 redundant configuration using different repair philosophies. In model 3, the proposed Markov model was also compared with the IEC 61508 approach for redundant SISs and a reliability improvement between 9% - 15% were observed. The model 2 on the other hand integrates the Dangerous Detected (DD) failure rates in the unavailability assessment of redundant SISs subject to process demand assuming that CCF does not occur. An additional reliability model was developed in this research for a 1oo3 redundant configuration subject to process demand excluding CCF and its construction was verified using partial verification method. Furthermore, a generic framework for reliability assessment of 1oon redundant SISs is provided in this thesis in conjunction with some guidelines for future researchers as how to conduct reliability assessment of SISs subject to process demands. The accuracy of the proposed Markov models is verified for industrial application case studies. It is demonstrated that the proposed approach provides a sufficiently robust result for all demand rates, demand durations, common cause failures, dangerous detected and undetected failure and associated repair rates for SISs. The effectiveness of the proposed models offers a robust opportunity to conduct reliability assessment of redundant SISs subject to process demands.
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Dongale, Prasad J. "Equipment condition assessment and its importance in estimation and prediction of power system reliability." Thesis, WIchita State University, 2008. http://hdl.handle.net/10057/2027.
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Transmission and Distribution Electric Utilities have a vast amount of assets distributed over their system in the form of various equipment. As part of an asset management program, electric utilities keep focusing on the inspection and maintenance activities of these assets to improve system performance, reliability, and to ensure cost-effective expenditures. Therefore methodology that will reflect these inspection and maintenance efforts in terms of overall condition of the equipment is needed. Also techniques are needed to assess the impact of inspection and maintenance activities on the overall reliability of systems performance. To achieve this, a methodology for the assessment of equipment condition and the estimation of the health index for transformers and circuit breakers was developed. After that, a technique to estimate the failure rate from the equipment health index was used. Then an IEEE test case was selected to demonstrate its impact on system reliability indices with the help of a predictive reliability assessment software tool, Milsoft Utility Solution. As part of equipment condition assessment method for transformer and circuit breaker, failure modes and maintenance practices for these equipment was reviewed. Based on this review, parameters were selected for condition assessment which will provide significant information about the equipment condition and will also justify the cost and efforts. For each of the parameters, a score and weight were defined, and guidelines were developed to assign them. Also, ways in which online monitoring systems can contribute to equipment condition assessment were presented briefly. A technique was used to convert the equipment health index into its failure rate. Then an IEEE reliability test case was modeled using the Milsoft software, incorporating this estimated failure rate and studied system’s behavior in terms of reliability indices. It was observed that developing such models will provide more realistic information about the system’s actual performance and will demonstrate the way in which impact of the inspection and maintenance efforts can be accounted.Thesis (M.S) - Wichita State University, College of Engineering, Dept. of Electrical and Computer Science Engineering
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Dongale, Prasad J. Jewell Ward. "Equipment condition assessment and its importance in estimation and prediction of power system reliability." A link to full text of this thesis in SOAR, 2008. http://hdl.handle.net/10057/2027.
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Khan, Zahir Hoosain. "Improving the reliability performance of medium voltage networks." Master's thesis, University of Cape Town, 2015. http://hdl.handle.net/11427/20047.
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The aim of this dissertation is to investigate alternative, more reliable and cost effective ways of improving the reliability performance of medium voltage networks. Customers are mainly affected by faults on the distribution MV network, to which, consequently, we have to pay particular attention. A major requirement on electricity supply systems is high supply reliability for the customer which is mainly determined by the distribution networks. Power system reliability is an essential factor in the quality of supply and is directly related to the number and duration of outages. By analysing the power system properly, the weaknesses will then be identified and improvements can be introduced to minimise the occurrence of outages. A decrease in the outage rate will result in an improvement in reliability and quality of supply of the distribution MV network. The dissertation focuses on improving the network management by increasing the level of network automation and control which improves the operating efficiency of medium voltage distribution networks. Steps are shown how to equip the network according to progressive investment capability, from Fault Path Indicators (FPIs) and remote control Pulseclosing technologies to automatic FuseSavers and Tripsavers used in a feeder automation scheme to minimise the number of disturbances and the outage durations experienced when they occur. The results of a study analysing the impact of different intelligent automation solutions on the reliability performance of Medium Voltage distribution networks are presented in the dissertation. The respective system topologies are modelled and the resulting system reliability performance is determined by reliability calculations such as the SAIDI and SAIFI values. The results show that the distribution automation technologies can have a very significant impact on both the SAIDI and SAIFI performance of the systems. Further, selected details related to the implementation of such intelligent automation schemes are presented in this dissertation.
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Kim, SeokWon Abraham 1970. "Modeling for hot-electron reliability simulation." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/36589.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1995.Includes bibliographical references (leaves 74-78).
by Jeffery Seokwon Kim.
M.Eng.
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Saw, Bun Liong. "Infrared and passive microwave satellite rainfall estimate over tropics." Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/4267.
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Thesis (M.S.)--University of Missouri-Columbia, 2005.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (December 19, 2006) Includes bibliographical references.
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Clark, Howard. "The use of simulation for the investigation of quality economics in a cell-based manufacturing environment." Thesis, University of Nottingham, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263390.
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This thesis is an investigation into the use of simulation for the study of quality economics within a cell-based manufacturing environment. Quality is, for the purposes of this report, considered to mean conformance to specification. This research identified two distinct areas of study that could be considered part of quality economics. The economic design of quality control procedures is concerned with the "micro" side of quality economics, focusing on single processes, whilst quality costing systems represent the "macro" side, focusing on entire production lines, departments or organisations. A critical analysis of these areas suggested a number of deficiencies. In addition, a number of economic quality models were considered. These were found to focus on the "macro" side of quality economics, with no consideration of the effect of specific changes to specific processes - the "micro" side. It was suggested that simulation would be a suitable approach for overcoming some of these deficiencies. The precedent for the use of simulation to investigate quality economics is considered, with the conclusion that none of the existing approaches reviewed were able to model the manufacturing systems under consideration in sufficient detail. Therefore, a new approach is outlined, and the thesis then describes the development and validation of this approach. A number of examples are given that are intended to both illustrate the simulation approach and, hopefully, provide certain generic information that can be applied to any similar manufacturing process. Conclusions are drawn regarding the success of the project relative to the initial aims, and the contribution to our understanding of quality economics. Finally, a number of recommendations for further work are given.
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Abrons, Andrew. "An investigation into the applicability of reliability centred maintenance and expert systems technology for developing preventative maintenance in the steel industry." Thesis, University of the West of England, Bristol, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240857.
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Hogan, Paul Anthony. "A knowledge-based system for automated fault analysis of hydraulic systems." Thesis, University of Bath, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332776.
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Gomm, James Barry. "On-line detection of fault conditions in controlled industrial processes." Thesis, Liverpool John Moores University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.304482.
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Pereira-Leite, Margarida Maria Alvim. "A procedure for monitoring the mean of autocorrelated industrial data." Thesis, University of Newcastle Upon Tyne, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333934.
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Owen, Bryn David. "The design and implementation of a systems model to meet ISO 9000-1987." Thesis, University of Salford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336078.
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Robinson, David Charles. "Computer based on-line quality control." Thesis, University of Portsmouth, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292316.
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Odoom, Emmanuel Ricky. "A methodology for operational reliability programme development and assessment with application to ship propulsion plant." Thesis, University of Exeter, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322014.
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