Rozprawy doktorskie na temat „VOLTAGE LIMIT”

Voltage security assessment is becoming a more and more important issue due to the fact that electrical power systems are more prone to voltage instability under increased demand, and it can be time-consuming to determine the actual level of voltage security in large power systems. For this reason, this thesis presents a novel method for calculating the margin of voltage collapse that is based on the Continuation Power Flow (CPF) method. The method offers a flexible and reliable solution procedure without suffering from divergence problems even when near the bifurcation point. In addition, the new method accounts for reactive power limits. The algorithmic continuation steps are guided by the prediction of Q-limit breaking point. A Lagrange polynomial interpolation formula is used in this method in order to find the Q-limit breaking point indices that determine when the reactive power output of a generator has reached its limit. The algorithmic continuation steps will then be guided to the closest Q-limit breaking point, consequently reducing the number of continuation steps and saving computational time. The novel method is compared with alternative conventional and enhanced CPF methods. In order to improve CPF further, studies comparing the performance of using direct and iterative solvers in a power flow calculation have also been performed. I first attempt to employ the column approximate minimum degree (AMD) ordering scheme to reset the permutation of the coefficient matrix, which decreases the number of iterations required by iterative solvers. Finally, the novel method has been applied to a range of power system case studies including a 953 bus national grid transmission case study. The results are discussed in detail and compared against exiting CPF methods.

A interligação dos sistemas elétricos de potência (SEPs) resultou em um aumento na complexidade dos mesmos. Além disso, devido a pressões econômicas e ambientais, os sistemas têm operado mais próximos aos seus limites de transmissão, o que aumenta a relevância de análises de segurança no contexto de estabilidade de tensão. Neste cenário, problemas associados à capacidade de transmissão do SEP, como a bifurcação induzida por limite (BIL), tornam-se mais importantes, criando a necessidade de ferramentas de análise apropriadas. Um dos objetivos deste projeto de mestrado é estudar mais profundamente as BILs para que se possa tratar melhor o fenômeno no contexto de estabilidade de tensão. Outro objetivo é o desenvolvimento de técnicas para avaliação da margem de estabilidade de tensão (MET) considerando a possibilidade de ocorrência de BIL. Finalmente, dada a grande importância e ampla utilização da análise de sensibilidade da MET devido à bifurcação sela-nó (BSN) em estudos de estabilidade de tensão, o equacionamento do problema de análise de sensibilidade da MET devido à BIL é o terceiro objetivo deste trabalho. A análise de sensibilidade é importante pois, não só fornece mais informações sobre o fenômeno de instabilidade e seus mecanismos, mas também auxilia na análise de segurança de SEPs, fornecendo informações sobre quais ações de controle serão mais eficazes na manutenção da MET e quais contingências serão mais severas. Isto é, quais mudanças no sistema mais afetam a MET. No entanto, este tipo de análise só foi realizado para o caso em que a MET é determinada por um ponto de BSN, não para o caso da BIL. Com o intuito de possibilitar que ferramentas de seleção de controles preventivos tratem o fenômeno da BIL, realizou-se uma análise de sensibilidade do ponto de BIL similar à análise usual baseada na BSN. Outra contribuição deste trabalho é uma formulação suave de limites complementares que foi aplicada ao problema de limites de injeção de potência reativa de unidades geradoras. A formulação proposta transforma, pelo menos numericamente, a BIL em uma BSN que pode ser detectada através de métodos já consolidados na literatura.
The interconnection of electric power systems (EPSs) led to an increase in security assessment complexity. Besides, due to economical and environmental inuences, EPSs have been operating closer to their transmission limits, which raises the relevance of security assessment in the context of voltage stability. In this scenario, problems related to EPS power transmission capacity, such as the limit induced bifurcation (LIB), become more important and bring the need of appropriate analysis tools. One of the goals of this project is to study the LIB problem more deeply, so it can be better understood in the context of voltage stability. Another objective is the development of methods for evaluating the load margin (LM) considering the possible occurrence of LIBs. Finally, since the LM sensitivity analysis due to saddle-node bifurcation (SNB) plays a highly important role in voltage stability studies, developing a method for LM sensitivity analysis due to LIB is our third objective. The sensitivity analysis is important not only because it provides information on the instability phenomenon and its mechanisms, but it is also useful for EPS security assessment, since it may provide knowledge on which control actions will be more eective in increasing the LM and which contingencies may be more severe. However, this analysis has been performed only for the case in which the LM is determined by a SNB point, not for the LIB case. With the intention of enabling pre-existing preventive control selection tools to treat the LIB phenomenon, a sensitivity analysis was performed at the LIB point similarly to what was developed for the SNB. Another contribution of this work is a smoothing formulation for complementary limits that was applied to the problem of limited reactive power injection of generating units. The proposed formulation transforms, at least numerically, the LIB in a SNB, which may be detected through methods already established in literature.

Master’s thesis is concerned with instrument transformers, which are used in conjunction with numerical protection relays. Therefore mainly with protective transformers of class P and transformers dimensioned for transient effects, which are important e.g. for fast differential or distance protections. The introduction includes fundamental notions, quantities and equations, which refers to instrumental current and voltage transformers. Below are mentioned connection diagrams of these transformers applied to specific electrical network types and faults, of which identification is required. These diagrams and faults are supplied with math equations and eventually with phasor diagrams. Noted informations corresponds to the present standards. Task of the next part is to compile requirements for dimensioning of current transformers, which imposes digital protections from ABB, AREVA and Siemens companies. These requirements, which mostly defines the minimal accuracy limit factor or the knee-point voltage of current transformer, are specified for individual protection terminals, eventually for specific protective functions. Part of the thesis is computer program developed as macro in the Microsoft Office Excel program via Visual Basic for Applications programming language. Program uses equations noted in this work and it can be used for quick dimensioning of current transformers for protective terminals from manufactures mentioned above.

Die Arbeit befasst sich mit der Erforschung und Anwendung der Kelvinsonden-Rasterkraftmikroskopie. Die Technik wird bezüglich der Quantität der gemessenen Werte und der erzielbaren lateralen Auflösung untersucht und auf diverse Probensysteme angewandt. Die so erhaltenen nanoskopischen Werte werden mit markoskopischen Messergebnissen verglichen. Sowohl die elektrostatische Kraft zwischen der Messspitze und der Probenoberfläche als auch deren Gradienten können zur Minimierung der elektrostatischen Wechselwirkung herangezogen werden. Die Detektion des Kraftgradienten zum Aufbau eines Regelkreises erweist sich gegenüber der Kraftdetektion überlegen. Die experimentell ermittelten Befunde werden durch eine Rechnersimulation bestätigt. Diese zeigt die Möglichkeit von quantitativen Ergebnissen für laterale Objektgrößen im Bereich von einigen Nanometern. Im Experiment kann dies gezeigt werden. Es folgt die Anwendung der Kelvinsonden-Rasterkraftmikroskopie: Nanoskopisch ermittelte Werte der Austrittsarbeitsänderung von Metalleinkristall-Oberflächen durch die Adsorption von C_60 entsprechen Literaturwerten, die mit makroskopisch messenden Methoden ermittelt wurden. Sich zeitlich ändernde Oberflächenpotentiale von einer organischen Solarzelle und von lateral unterschiedlich dotiertem Silizium lassen sich quantitativ messen. Der sich bei der Adsorption von Oktadezyl-Phosphonsäure auf Glimmer und Graphit bildende elektrostatische Dipol wird untersucht und abgebildet. Das Wachstumsverhalten und die Austrittsarbeit der organischen Moleküle PTCDA und Alq_3 auf den teilweise mit KBr bedeckten Metallsubstraten Au und Ag wird untersucht. Schlussendlich wird gezeigt, dass mit der Kelvinsonden-Rasterkraftmikroskopie sogar der molekülinterne Dipol der vier Butyl-Gruppen von Tetra-3,5-di-ter-butyl-phenyl-Porphyrinen aufgelöst werden kann.

Doctor of Philosophy
Department of Electrical and Computer Engineering
Anil Pahwa
Shelli K. Starrett
Analysis of power system voltage stability has practical value in increasing wind penetration levels. As wind penetration levels increase in power systems, voltage stability challenges arise due to locating wind resources far away from load centers. This dissertation presents several different voltage stability methods for sizing new wind farms. Power system wind penetration levels depend on the available voltage stability margins (VSMs) of the existing power system and system load characteristics. Three new iterative methods have been developed to maximize wind penetration level in weak power systems based on systems’ VSMs. The first two methods use an iterative approach for increasing the size of each wind farm until reaching the collapse point. Wind farms with less negative impact on system VSMs are sized larger than others. A third wind farm sizing method has been developed using modal analysis in conjunction with the traditional voltage stability method (Q-V method). Wind farms are placed at buses in the power system which have the lowest negative impact on voltage instability modes (strong wind injection buses). By placing the wind farms at the strongest wind injection buses, higher amounts of wind power can be injected into the power system. To further increase wind penetration in weak power systems, two additional techniques are introduced and applied to the western Kansas power system. The first technique uses modes of voltage instability to place voltage support equipment like static var compensators at locations in the power system where they provide the needed reactive power support for increasing levels of wind penetration. The second technique uses the fact that wind patterns at a wind farm site may rarely allow the wind farm to produce its maximum capacity during the peak loading hours. Wind farm maximum sizes can be increased above their maximum voltage stable size limit without driving the power system into becoming voltage unstable. Preventing voltage collapse for the additional increases in wind farm sizes is accomplished by disconnecting some wind turbines inside the wind farm during critical times to reduce its power output to a voltage stable level.

Distributed generation (DG), in the form of grid connected photovoltaic (PV) systems, is expected to grow substantially throughout the South West Interconnected System (SWIS). The growth of these systems is anticipated to meet a portion of the local energy requirements and offset carbon emissions. The intermittency of the solar resource and its relationship with conventional load and voltage management, presents challenges for Western Power (the utility responsible for the SWIS). Therefore, investigating the effects and management of grid connected PV systems in the SWIS, with respect to its voltage operation limits, formed the primary objective of this project. The project studies were performed on a typical Western Power (WP) low voltage (LV) network model, in DIgSILENT Power Factory software, using WP residential network loadings data along with solar radiation and temperature data. The power flow simulation results concluded that PV penetration levels of up to 25% can be feasible in specific overhead (OH) networks. Similarly, PV penetration levels of up to 49% can be sustained in particular underground (UG) networks. Furthermore, these penetration levels were heavily dependant on existing LV network balance and voltage profiles. The findings of the project also demonstrated that grid connected PV systems are not offsetting the peaky SWIS residential network load profile. Therefore, high grid connected PV system penetration, with no electrical storage and demand management, provides substantially lower grid support value when compared to dispatchable DG technologies.

In questo elaborato si è analizzato il comportamento meccanico di volte e cupole in muratura soggette a carichi verticali ed azioni orizzontali. Per prima cosa sono state studiate le cupole in campo elastico lineare attraverso dei confronti con dei modelli agli elementi finiti, e poi si sono affrontate delle analisi in campo non lineare. P er la volta a botte è stata fatta anche l'analisi limite e delle verifiche di sicurezza sismica, confrontate poi con le analisi statiche non lineari. Infine si sono svolte delle analisi statiche non lineari sul caso studio e sulle principali volte (a botte, padiglione e crociera).

博士
國立成功大學
電機工程研究所
84
In this dissertation, the steady-state small dis -turbance voltage stability limit for a radial distribution system is thoroughly analyzed. The solutions for radial distribution systems. By this method, an equivalent 2-bus network can be obtained during the solving process. Based on the 2-bus network, the steady-state load limit and voltage stability limit are investigated. The circle diagrams and Jacobian determinant are developed first to derive the load limit and voltage stability limit for radial distribution systems. For the purpose of checking the limits equations derived by the authors, the well-known L stability indicator is adopted for the task of justification. The consistency among these methods is shown. It is shown that the positive Jacobian determinant corresponds to an L indicator less than 1 which meets the voltage stability criterion. To show the effects of load models on the voltage stability limit, a composite load model composed of a part of constant power load, a part of constant impedance load and a part of constant current load is adopted to derive the general equation of voltage stability limit. It is found that the voltage stability problems are mostly caused by the constant power load. In the literature, almost all the tasks of proving the uniqueness of a voltage solution for a radial distribution system are based on a 2-bus system. In this dissertation, the authors derive a general equation of the [dV/dP] of load bus, and by checking the sign of [dV/dP] of each load bus, the uniqueness of a voltage solution can be shown. The method of proof developed is more general than those methods published.

ABSTRACT Load flow (LF) is an important tool in the planning and operation of power systems. It is usually solved using conventional numerical techniques like Newton-Raphson (NR) and Gauss-Siedel (GS). Most of these techniques depend on getting the inverse of the Jacobian matrix of the system. Such techniques fail to solve the load flow in some conditions, like Heavy loaded system, Ill-conditioned Jacobian matrix. In this thesis an application of particle swarm optimization (PSO) in solving the load flow problem as an optimization problem is discussed. A MATLAB program has been developed for PARTICLE SWARM OPTIMIZATION to solve load flow problem. Program is tested on IEEE 5, 14 and 30 bus system and the results are compared with conventional method.

碩士
國立臺北科技大學
機電整合研究所
87
Taiwan power system in the peak-load period has a large amount of power flow through 345kV-transmission lines from the central and southern areas to northern area. In this time, if one of these lines is tripped, the voltage stability of the power system would be affected. Hence, how to prevent voltage collapse and compensate the reactive power of a power system become very important. In the past, most of researches in the field of voltage stability used uniform rate to deal with the system load increase. In this paper, we analyze the power system stability, focusing on the limit of transmission line power flow between two areas. This paper uses PSS/E, IPLAN and OPF analysis package to develop a helpful method to generate P-V curves for Taiwan power system voltage stability analysis. Using these P-V curves, it is easy to identify the saddle-node bifurcation point and to determine the weak bus index and real power transmission limit from the central area to northern area. Besides, in normal operating condition, some line outage cases with 345kV-interface line from central area to northern area and some generator outage cases of the voltage stability of Taiwan power system were studied. Finally, the optimal compensation of the parallel capacitors and series capacitors to improve the voltage stability of the system were proposed in this paper.

碩士
國立成功大學
電機工程研究所
83
Analysis of voltage stability limit is an important topic in the study of a distribution system. In this thesis, the effects of different types of static loads is investigated on the steady-state voltage stability limit for a radial distribution system. The loads adopted in the investigation include constant power loads, constant impedance loads and constant current loads. Furthermore, the uniqueness and existence of the voltage solution are discussed. In solving the load flow problems of the radial power network, the DistFlow technique has been proposed as the most suitable method. In this method, an equivalent two-bus network will be obtained simultaneously. Based on that, the analysis in this thesis is mainly concentrated on the two-bus system. The detailed simulated results are presented to justify the opinions proposed.The result reveal that when a larger part of constant current or constant impedance load is added to the total load, the voltage stability limit will move far into the lower branch of the P-V curve and multiple load flow solutions may exist.

Since deregulation of the electric power industry, investment in the sector has not kept up with demand. State grids were interconnected to form vast power networks, which increased the overall system’s complexity. Conventional generation sources have, in some cases, closed under financial stress caused by the growing penetration of renewable sources and unfavourable government measures. The power system must adapt to a more demanding environment to that for which it was conceived. This thesis investigates the robustness of planning and simulation study tools for the determination of bus-voltages and voltage stability limits. It also provides an approach to obtain greater certainty in the determination of voltages where conventional methods fail to be deterministic. Two complementary methods for determining the collapse voltage are developed in this thesis. The first method applies Robust Padé approximations to the holomorphic embedding load flow method; while the second method uses the Newton-Raphson numerical calculation method to obtain both high and low voltage solution branches, and voltage stability limits of power system load buses. The proposed methods have been implemented using MATLAB and been demonstrated through a number of IEEE power system test cases. The robust Padé approximation algorithm improves the reliability of solutions of load flow problems when bus-voltages are presented in Taylor series form by converting the series into optimised rational functions. Differences between the classic Padé approximation algorithm and the new robust version, which is based on singular value decomposition (SVD), are described. The new robust approximation method can determine an optimal rational function approximation using the coefficients of a Taylor series expansion. Consequently, the voltage collapse points, as well as the steady-state voltage stability margin, can be calculated with high reliability. Voltage collapse points (i.e. branching points) are identified by using the locations of poles/zeros of a rational function approximation. Numerical examples are devised to illustrate potential use of the proposed method in practical applications. Use of the Newton-Raphson method, combined with the discrete Fourier transform and robust Padé approximation, enables the calculation of the voltage stability limits and both the high and low voltage solution branches for the load buses of a power system. This can work to a great advantage of existing N-R based software users, as problems of initial guess, multiple solutions and Jacobian matrix conditioning when operating close to the voltage collapse point are avoided. The findings are assessed by comparisons with conventional Newton-Raphson, the holomorphic embedding load flow method, and continuation power flow method. This thesis contains a combination of conventional and publication formats, where some introductory materials are included to ensure that the thesis delivers a consistent narrative. For this reason, the first two chapters provide the required background information, research gap identification and contributions, whilst other chapters are written to provide more detailed work that has not yet been published or to summarise the research outcomes and future research directions. Furthermore, publications are listed in their publication formats, complete with statements of the authors’ contributions.
Thesis (Ph.D.) -- University of Adelaide, School of Electrical and Electronic Engineering, 2019

Determining the maximum power system loadability, as well as preventing the system from being operated close to the stability limits is very important in power systems planning and operation. The application of optimization techniques to power systems security and electricity markets is a rather relevant research area in power engineering. The study of optimization models to determine critical operating conditions of a power system to obtain secure power dispatches in an electricity market has gained particular attention. This thesis studies and develops optimization models and techniques to detect or avoid voltage instability points in a power system in the context of a competitive electricity market. A thorough analysis of an optimization model to determine the maximum power loadability points is first presented, demonstrating that a solution of this model corresponds to either Saddle-node Bifurcation (SNB) or Limit-induced Bifurcation (LIB) points of a power flow model. The analysis consists of showing that the transversality conditions that characterize these bifurcations can be derived from the optimality conditions at the solution of the optimization model. The study also includes a numerical comparison between the optimization and a continuation power flow method to show that these techniques converge to the same maximum loading point. It is shown that the optimization method is a very versatile technique to determine the maximum loading point, since it can be readily implemented and solved. Furthermore, this model is very flexible, as it can be reformulated to optimize different system parameters so that the loading margin is maximized. The Optimal Power Flow (OPF) problem with voltage stability (VS) constraints is a highly nonlinear optimization problem which demands robust and efficient solution techniques. Furthermore, the proper formulation of the VS constraints plays a significant role not only from the practical point of view, but also from the market/system perspective. Thus, a novel and practical OPF-based auction model is proposed that includes a VS constraint based on the singular value decomposition (SVD) of the power flow Jacobian. The newly developed model is tested using realistic systems of up to 1211 buses to demonstrate its practical application. The results show that the proposed model better represents power system security in the OPF and yields better market signals. Furthermore, the corresponding solution technique outperforms previous approaches for the same problem. Other solution techniques for this OPF problem are also investigated. One makes use of a cutting planes (CP) technique to handle the VS constraint using a primal-dual Interior-point Method (IPM) scheme. Another tries to reformulate the OPF and VS constraint as a semidefinite programming (SDP) problem, since SDP has proven to work well for certain power system optimization problems; however, it is demonstrated that this technique cannot be used to solve this particular optimization problem.

Voltage unbalance performance of a power line depends on a few parameters that are not necessarily constant at any given instance. The random nature of a power system raises questions around the ability of a system planner to allocate equitable share of the power quality parameters, like voltage unbalance, at design stage. Even a more interesting question is whether applying current methods will guarantee that emissions will be under the set limits. The presence of single or dual phase feeders on such a line will result in a more dynamic voltage unbalance. The first part of this research is a study on deterministic method of voltage unbalance allocation presented by the IEC. The IEC 61000-13-3 report is a comprehensive guideline and the best place to start when looking to develop an emissions standard for voltage unbalance. This dissertation presents a method that can be used to set planning levels for unbalance emission at various voltage levels in order to avoid high voltage unbalance at the end user. The method depends on the agreed power of the customer, the power of the unbalanced load, and the system characteristics. The method works well for short feeders with roughly the same negative sequence impedance and equal short circuit levels. In South Africa, however, there are radial feeders that span over 100km. Hence on such a feeder, there can be ratios of 1:10 between sending end and the last customer on the line. Preliminary research revealed that IEC 61000-6-3, a report on allocation of harmonics, has a method applicable to long feeders. This method was investigated extensively and applied to voltage unbalance allocation. At the core of the method is the assumption that feeders have an even distribution of load. To illustrate the application of this method an example is given. The second part of the study explores a stochastic method of voltage unbalance allocation. In this study the possibility of random connection is considered. A Monte Carlo study is presented. The impact of various parameters are analysed and the findings reveal that phase allocation has the most influence on emission. The results show that the method of random connection of loads can be applied in special conditions only i.e. were sizes of loads do not differ greatly and the number of required connections are low.
Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2011.

The research is motivated by the need to address two major challenges in wind power integration: how to mitigate wind power fluctuation and how to ensure stability of the farm and host grid. It is envisaged that wind farm power output fluctuation can be reduced by using a specific type of buffer, such as an energy storage system (ESS), to absorb its negative impact. The proposed solution, therefore, employs ESS to solve the problems. The key research findings include a new technique for calculating the desired power output profile, an ESS charge-discharge scheme, a novel direct-calculation (optimization-based) method for determining ESS optimal rating, and an ESS operation scheme for improving wind farm transient stability. Analysis with 14 wind farms and a compressed-air energy storage system (CAES) shows that the charge-discharge scheme and the desired output calculation technique are appropriate for ESS operation. The optimal ESSs for the 14 wind farms perform four or less switching operations daily (73.2%-85.5% of the 365 days) while regulating the farms output variation. On average, the ESSs carry out 2.5 to 3.1 switching operations per day. By using the direct-calculation method, an optimal ESS rating can be found for any wind farm with a high degree of accuracy. The method has a considerable advantage over traditional differential-based methods because it does not require knowledge of the analytical form of the objective function. For ESSs optimal rating, the improvement in wind energy integration is between 1.7% and 8%. In addition, a net increase in grid steady-state voltage stability of 8.3%-18.3% is achieved by 13 of the 14 evaluated ESSs. For improving wind farm transient stability, the proposed ESS operation scheme is effective. It exploits the use of a synchronous-machine-based ESS as a synchronous condenser to dynamically supply a wind farm with reactive power during faults. Analysis with an ESS and a 60-MW wind farm consisting of stall-regulated wind turbines shows that the ESS increases the farm critical clearing time (CCT) by 1 cycle for worst-case bolted three-phase-to-ground faults. For bolted single-phase-to-ground faults, the CCT is improved by 23.1%-52.2%.
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Thesis (M.S.)--University of Wisconsin--Madison, 1991.
Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 34-37).

La gran parte del patrimonio storico mondiale è costituita da costruzioni in muratura, generalmente realizzate tramite volte monumentali. Alcune di esse possiedono una geometria talmente complessa da rendere particolarmente onerosa l'applicazione delle moderne tecniche di analisi strutturale. Peraltro esse sono intrinsecamente non lineari, attese le proprietà costitutive del materiale muratura, e affette da notevoli incertezze in considerazione del fatto che è molto difficile conoscere la reale geometria della struttura e del tutto velleitario valutare l'entità delle azioni e delle modifiche intervenute nel corso del tempo. In questo contesto, diventa sempre più stringente la necessità di sviluppare appropriati strumenti analitici capaci di mettere in condizione ingegneri ed architetti di comprenderne il reale, o quantomeno, un ragionevole grado di sicurezza strutturale. Al fine di superare alcuni dei limiti palesati all'interno delle formulazioni di analisi al discreto disponibili in letteratura, il presente lavoro di tesi espone una recente riformulazione del metodo delle reti di spinta, che mira ad aumentare il grado di efficienza computazionale e ad estendere il campo di applicazione alle reti costituite da bordi non vincolati, anche in presenza di carichi orizzontali. Inoltre con lo scopo di validare ulteriormente il metodo, questo è stato applicato con successo ad una classe di costruzioni murarie contraddistinta da una notevole complessità geometrica e strutturale: le volte e le scale elicoidali in muratura.

mondo universitario ha subito un’ondata di cambiamenti che si possono ricondurre alla ricerca dell’eccellenza, declinata secondo le due dimensioni della valutazione e della rendicontazione. Tre sono quelli più evidenti: il primo, il passaggio da una ricerca curiosity driven a una ricerca funzionale al raggiungimento di risultati valutabili in tempi brevi; dalla ricerca pura a quella applicata, da un approccio problem-making a uno problem-solving, da una conoscenza come processo a una conoscenza come prodotto, da un modello disinteressato a uno utilitaristico (Barnett, 1994); il secondo, riguardante l’offerta formativa: dal momento che si è modificato il modo di concepire l’apprendimento; i curricula tendono a essere definiti in termini di risultati di apprendimento predefiniti (Blackmore, 2016); il terzo, peculiare della struttura amministrativa: dal momento in cui sono divenute essenziali una serie di nuove sovrastrutture (programmazione, valutazione, controlli, comunicazione) rispetto al mandato originario della struttura universitaria si registra un aumento consistente del personale delle strutture amministrative. Questi cambiamenti devono fare i conti con la perdita di prestigio della vita accademica, il cambiamento del ruolo dello studente, che è diventato sempre più importante e l’aumento delle procedure burocratiche che rischiano di ingessare un sistema un tempo caratterizzato da un’elevata autonomia. Per consentire alle strutture universitarie di affrontare le sfide culturali a partire dagli anni Settanta nelle università nord-americane si sono strutturate iniziative finalizzate allo sviluppo e alla promozione di una migliore offerta formativa. Tali iniziative vengono definite con l’espressione Faculty Development (FD), una policy accademica finalizzata a creare le condizioni per un miglioramento delle competenze di tutti coloro che sono coinvolti nelle attività svolte in un ateneo. Nella realtà italiana emerge la mancanza di una vera politica di formazione al teaching per i ricercatori e i docenti universitari, per non parlare dell’esigenza di superare il pregiudizio, di gentiliana memoria, secondo il quale non è necessario apprendere a insegnare, ma sia sufficiente avere successo nella ricerca, cui si aggiunge nell’ultimo decennio una continua e affannata richiesta al personale accademico di azioni organizzative, valutative e documentali, che assorbono tempo e energie senza il supporto di adeguati apparati gestionali e senza predisporre indagini valutative capaci di misurare l’effettivo esito di tutte queste azioni. L’effetto finale è un evidente declino (Capano et al., 2017) dell’istituzione universitaria. Si può ipotizzare che la cultura del organizzazione propria del Faculty Development possa contribuire nel contesto italiano a fornire azioni a supporto del cambiamento: è quanto mai essenziale dotare gli atenei di risorse funzionali a riqualificare la vita accademica, fornendo al personale accademico gli strumenti necessari per performare una buona scholarship, realizzare un’efficace offerta formativa e attuare adeguate forme di terza missione, capaci di incrementare la vita culturale della comunità. Il presente studio si propone come un’analisi sistematica della letteratura sul tema del Faculty Development, che persegue l’obiettivo di sviluppare una disamina estesa dell’oggetto, in modo che l’esplicitazione della datità raccolta fornisca un’analisi del fenomeno che possa essere di supporto a un’avveduta educational policy nel campo della formazione universitaria. Nel contesto italiano ad oggi non esiste una cultura di attenzione ai contesti di apprendimento universitario. L’offerta formativa è concepita come offerta di pacchetti curriculari e la predisposizione delle condizioni di apprendimento per il conseguimento del titolo universitario si risolve nella organizzazione di una serie di lezioni, frontali o laboratoriali, senza che tutto questo sia innervato da una specifica intenzionalità didattica. Questa immagine poco confortante non intende affatto trascurare tutti i casi di buone prassi sviluppati nei vari corsi di studio, ma il buono che emerge è demandato all’impegno del singolo, senza che l’istituzione universitaria si interroghi sul come predisporre le condizioni per il potenziamento della qualità dei processi di apprendimento. A fronte di questa situazione la necessità di migliorare la qualità dell’insegnamento non è mai stata così stringente e sfidante come lo è oggi, in un clima di continuo cambiamento della formazione superiore. Nuove tendenze definiscono la formazione superiore, attraversando confini istituzionali e nazionali. Essi influiscono sul modo in cui un insegnamento efficace viene concettualizzato, condotto e supportato, valutato, valorizzato e riconosciuto. È necessario affrontare temi quali l’inadeguata preparazione per il lavoro accademico nei corsi di studio magistrali, l’incapacità dei docenti a trasferire competenze, la crescente complessità degli ambienti accademici, le attese e le responsabilità istituzionali, la necessità di preparare meglio gli studenti con bisogni diversi, e la necessità di stare al passo con i balzi della conoscenza e i cambiamenti nelle professioni. Migliorare la qualità della didattica è inoltre essenziale perché consente di ridurre il numero degli abbandoni. È venuto il momento di transitare da un’offerta formativa di tipo episodico a una prospettiva di esperienze di apprendimento in continuità nel tempo, per accompagnare la formazione dei docenti in un modo strutturalmente organizzato (Webster-Wright, 2009). Sulla base della rilevazione fenomenica, sono emerse le seguenti domande di ricerca: che cosa è il FD? Cosa consente di fare? Come si mette in pratica? Quali sono le potenzialità? Quali sono i limiti? Il FD ha il compito di incentivare i docenti ad interessarsi ai processi di insegnamento e apprendimento e a procurare un ambiente sicuro e positivo nel quale fare ricerca, sperimentare, valutare e adottare nuovi metodi (Lancaster et al. 2014). È finalizzato a promuovere cambiamento sia a livello individuale sia a livello organizzativo. Occupa un posto centrale il miglioramento delle competenze di teaching (Steinert, 2014). Due importanti obiettivi sono rappresentati dalla promozione delle capacità di leadership e di gestione dei contesti (Steiner et al., 2012). Una volta definite le metodologie del teaching, che possono essere oggetto di apprendimento da parte del personale accademico, è risultato necessario identificare le principali modalità formative che un centro di Faculty Development (FDc) dovrebbe mettere in atto per favorire l’apprendimento delle competenze didattiche. Per comprenderne la funzione reale è stato utile prendere in esame le attività proposte dai più importanti centri del panorama accademico nordamericano, analizzandone la struttura organizzativa, le risorse disponibili ed identificandone le due figure principali: il responsabile dell’organizzazione dei processi formativi e il responsabile della struttura. L’analisi dei casi ha consentito di evidenziare i molteplici servizi che possono essere forniti da un FDc. Questa analisi di realtà è risultata molto utile poiché ha offerto indicazioni pragmatiche ai fini di una politica accademica innovativa anche in ambito italiano. Alla luce degli argomenti sviluppati è stato possibile ipotizzare anche per gli atenei italiani l’istituzione di “Centri per la professionalità accademica”, indicando possibili iniziative da essi realizzabili, che potrebbero trovare spazio nella realtà del nostro paese.