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Journal articles on the topic 'POWER MISMATCH'

Author: Grafiati

Published: 11 September 2023

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1

Niazi, Kamran Ali Khan, Tamas Kerekes, Alberto Dolara, Yongheng Yang, and Sonia Leva. "Performance Assessment of Mismatch Mitigation Methodologies Using Field Data in Solar Photovoltaic Systems." Electronics 11, no. 13 (June 21, 2022): 1938. http://dx.doi.org/10.3390/electronics11131938.

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Partial shading and other non-ideal conditions cause electrical mismatches that reduce the output power generated by a photovoltaic (PV) system. It affects the overall performance and efficiency of PV systems. Therefore, a model is developed in MATLAB, which analyses the performance of the PV systems under real irradiance profiles and temperatures for various available mismatch mitigation methodologies, i.e., bypass diode, DC power optimizer, and differential power processing (DPP). More specifically, this study will help to understand the best mismatch reduction methodologies for a solar PV system under different scenarios. The results also are validated by comparing them with a similar PV system installed in SolarTechLAB, which also operates under the same irradiance and temperature conditions under which these models are tested. This study also presents novel results, covering discussions on the reverse voltage distribution under mismatch scenarios among bypass diode, DC power optimizer, and DPP techniques.

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2

Lorente, Daniel Gómez, Simone Pedrazzi, Gabriele Zini, Alberto Dalla Rosa, and Paolo Tartarini. "Mismatch losses in PV power plants." Solar Energy 100 (February 2014): 42–49. http://dx.doi.org/10.1016/j.solener.2013.11.026.

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3

Parks, G. T. "Fuel cycle transients under power mismatch." Annals of Nuclear Energy 14, no. 9 (January 1987): 511–15. http://dx.doi.org/10.1016/0306-4549(87)90069-7.

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4

Niazi, Kamran Ali Khan, Yongheng Yang, Tamas Kerekes, and Dezso Sera. "A Simple Mismatch Mitigating Partial Power Processing Converter for Solar PV Modules." Energies 14, no. 8 (April 19, 2021): 2308. http://dx.doi.org/10.3390/en14082308.

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Partial shading affects the energy harvested from photovoltaic (PV) modules, leading to a mismatch in PV systems and causing energy losses. For this purpose, differential power processing (DPP) converters are the emerging power electronic-based topologies used to address the mismatch issues. Normally, PV modules are connected in series and DPP converters are used to extract the power from these PV modules by only processing the fraction of power called mismatched power. In this work, a switched-capacitor-inductor (SCL)-based DPP converter is presented, which mitigates the non-ideal conditions in solar PV systems. A proposed SCL-based DPP technique utilizes a simple control strategy to extract the maximum power from the partially shaded PV modules by only processing a fraction of the power. Furthermore, an operational principle and loss analysis for the proposed converter is presented. The proposed topology is examined and compared with the traditional bypass diode technique through simulations and experimental tests. The efficiency of the proposed DPP is validated by the experiment and simulation. The results demonstrate the performance in terms of higher energy yield without bypassing the low-producing PV module by using a simple control. The results indicate that achieved efficiency is higher than 98% under severe mismatch (higher than 50%).

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Lee, Yongho, Soyeon Kim, and Hyunchol Shin. "A 24 GHz CMOS Direct-Conversion RF Receiver with I/Q Mismatch Calibration for Radar Sensor Applications." Sensors 22, no. 21 (October 27, 2022): 8246. http://dx.doi.org/10.3390/s22218246.

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A 24 GHz millimeter-wave direct-conversion radio-frequency (RF) receiver with wide-range and precise I/Q mismatch calibration is designed in 65 nm CMOS technology for radar sensor applications. The CMOS RF receiver is based on a quadrature direct-conversion architecture. Analytic relations are derived to clearly exhibit the individual contributions of the I/Q amplitude and phase mismatches to the image-rejection ratio (IRR) degradation, which provides a useful design guide for determining the range and resolution of the I/Q mismatch calibration circuit. The designed CMOS RF receiver comprises a low-noise amplifier, quadrature down-conversion mixer, baseband amplifier, and quadrature LO generator. Controlling the individual gate bias voltages of the switching FETs in the down-conversion mixer having a resistive load is found to induce significant changes at the amplitude and phase of the output signal. In the calibration process, the mixer gate bias tuning is first performed for the amplitude mismatch calibration, and the remaining phase mismatch is then calibrated out by the varactor capacitance tuning at the LO buffer’s LC load. Implemented in 65 nm CMOS process, the RF receiver achieves 31.5 dB power gain, −35.2 dBm input-referred 1 dB compression power, and 4.8–7.1 dB noise figure across 22.5–26.1 GHz band, while dissipating 106.2 mA from a 1.2 V supply. The effectiveness of the proposed I/Q mismatch calibration is successfully verified by observing that the amplitude and phase mismatches are improved from 1.0–1.5 dB to 0.02–0.19 dB, and from 10.8–23.8 to 1.1–3.2 degrees, respectively.

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6

Sinha, Shruti, Ch V. N. Rao, and Dhaval Pujara. "Balanced Power Amplifier Protection Against Load Mismatch." IEEE Microwave and Wireless Components Letters 28, no. 2 (February 2018): 165–67. http://dx.doi.org/10.1109/lmwc.2018.2792692.

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Liu, Lianxi, Shaopu Gao, Junchao Mu, and Zhangming Zhu. "A Low Power and Low Current-Mismatch Charge Pump with Dynamic Current Compensation." Journal of Circuits, Systems and Computers 28, no. 12 (November 2019): 1920007. http://dx.doi.org/10.1142/s021812661920007x.

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A novel low power charge pump (CP) that minimizes the mismatch between the charging and the discharging currents is proposed in this paper. The switching circuit with dynamic current compensation is used to reduce the power consumption of the proposed CP. In addition, precise current replication which makes use of the resistors and the low offset operational amplifiers (OTA) can enable a reduction in current mismatch caused by process mismatch. Meanwhile, the high output impedance can reduce the current mismatch caused by the channel length modulation effect. Based on the 0.18[Formula: see text][Formula: see text]m deep-Nwell CMOS process, the proposed CP can reduce the overall power consumption by 56% compared with the CP without current compensation, reduce the current mismatch caused by process mismatch to less than 0.9% and reduce the current mismatch caused by the channel length modulation effect to less than 0.01% over the output voltage ranging from 0.3 to 1.5[Formula: see text]V with 1.8[Formula: see text]V supply.

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8

Li, Shouping, Jianjun Chen, Bin Liang, and Yang Guo. "Low Power SAR ADC Design with Digital Background Calibration Algorithm." Symmetry 12, no. 11 (October 23, 2020): 1757. http://dx.doi.org/10.3390/sym12111757.

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This paper proposed a digital background calibration algorithm with positive and negative symmetry error tolerance to remedy the capacitor mismatch for successive approximation register analog-to-digital converters (SAR ADCs). Compensate for the errors caused by capacitor mismatches and improve the ADC performance. Combination with a tri-level switching scheme based on the common-mode voltage Vcm to achieve capacitor reduction and high switching energy efficiency. The proposed calibration algorithm significantly improves capacitor mismatch without resorting to extensive computation or dedicated circuits. The active area is 0.046 mm2 in 40 nm Complementary Metal-Oxide-Semiconductor (CMOS) technology. The post-simulation results show the effective number of bits (ENOB) improves from 8.23 bits to 11.36 bits, signal-to-noise-and distortion ratio (SNDR) improves from 51.33 dB to 70.15 dB, respectively, before and after calibration. This improves the spurious-free dynamic range (SFDR) by 24.13 dB, from 61.50 dB up to 85.63 dB. The whole ADC’s power consumption is only 0.3564 mW at sampling rate fs =2 MS/s and Nyquist input frequency, with a figure-of-merit (FOM) 67.8 fJ/conv.-step.

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9

Niazi, Kamran Ali Khan, Yongheng Yang, Tamas Kerekes, and Dezso Sera. "Reconfigurable Distributed Power Electronics Technique for Solar PV Systems." Electronics 10, no. 9 (May 10, 2021): 1121. http://dx.doi.org/10.3390/electronics10091121.

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A reconfiguration technique using a switched-capacitor (SC)-based voltage equalizer differential power processing (DPP) concept is proposed in this paper for photovoltaic (PV) systems at a cell/subpanel/panel-level. The proposed active diffusion charge redistribution (ADCR) architecture increases the energy yield during mismatch and adds a voltage boosting capability to the PV system under no mismatch by connected the available PV cells/panels in series. The technique performs a reconfiguration by measuring the PV cell/panel voltages and their irradiances. The power balancing is achieved by charge redistribution through SC under mismatch conditions, e.g., partial shading. Moreover, PV cells/panels remain in series under no mismatch. Overall, this paper analyzes, simulates, and evaluates the effectiveness of the proposed DPP architecture through a simulation-based model prepared in PSIM. Additionally, the effectiveness is also demonstrated by comparing it with existing conventional DPP and traditional bypass diode architecture.

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FLYNN, MICHAEL P., SUNGHYUN PARK, and CHUN C. LEE. "ACHIEVING ANALOG ACCURACY IN NANOMETER CMOS." International Journal of High Speed Electronics and Systems 15, no. 02 (June 2005): 255–75. http://dx.doi.org/10.1142/s0129156405003193.

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This paper reviews causes of and trends in MOS transistor mismatch, and assesses the implications for analog circuit design in the nanometer régime. The current understanding of MOS transistor mismatch is reviewed. In most cases, transistor mismatch is dominated by threshold voltage mismatch. Although, there is strong evidence that VT matching is improving as CMOS technology evolves, these improvements are countered by reductions in power supply that also accompany process scaling. In fact, the power consumption of analog circuits based on current design styles will increase with scaling to finer processes. It has long been known that thermal noise causes the power consumption of analog circuits to increase with scaling. However, unlike the case with thermal noise, new circuit techniques can break the accuracy-power constraints related to mismatch. These techniques are based on analog circuit redundancy, and take advantage of the tremendous transistor density offered by nanometer CMOS. This paper is primarily concerned with comparators, and in particular, with the use of comparators in flash ADCs; however, the analysis is also applicable to other circuits and applications.

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11

Cukalevski, N., J. Medanic, and M. Calovic. "Power Mismatch Detection and Estimation for Emergency Control." IEEE Power Engineering Review PER-7, no. 2 (February 1987): 33–34. http://dx.doi.org/10.1109/mper.1987.5527538.

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12

Ghahremani, Ali, Anne-Johan Annema, and Bram Nauta. "Load Mismatch Sensitivity of Class-E Power Amplifiers." IEEE Transactions on Microwave Theory and Techniques 67, no. 1 (January 2019): 216–30. http://dx.doi.org/10.1109/tmtt.2018.2873702.

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13

Khorami, Ata, and Mohammad Sharifkhani. "Zero-power mismatch-independent digital to analog converter." AEU - International Journal of Electronics and Communications 69, no. 11 (November 2015): 1599–605. http://dx.doi.org/10.1016/j.aeue.2015.07.010.

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14

Cukalevski, N., J. Medanic, and M. Calovic. "Power Mismatch Detection and Estimation for Emergency Control." IEEE Transactions on Power Systems 2, no. 1 (1987): 78–84. http://dx.doi.org/10.1109/tpwrs.1987.4335077.

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15

Yoon, Youngchang, Hyoungsoo Kim, Chang-Ho Lee, and J. Stevenson Kenney. "An inductive antenna mismatch recoverable RF power amplifier." Analog Integrated Circuits and Signal Processing 77, no. 3 (September 26, 2013): 495–502. http://dx.doi.org/10.1007/s10470-013-0160-5.

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16

Qi, Jun, Jing Wang, and Xiao Li Liang. "Analysis of Optimal Configuration of Building Integrated Photovoltaic (BIPV) Array under Moving Partial Shade." Applied Mechanics and Materials 291-294 (February 2013): 198–204. http://dx.doi.org/10.4028/www.scientific.net/amm.291-294.198.

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Influenced by partial shade, there are power losses induced by irradiation reduction, photovoltaic (PV) modules mismatch and maximum power point tracking (MPPT) failure. In order to raise power generation efficiency of building integrated PV (BIPV) power station, typical series-parallel PV array controlled with centralized MPPT is taken into consideration. Simulation model is constructed to describe the output characteristic of PV array under complex partial shade conditions. Due to bypass/blocking diodes, there are multiple peaks on P-V characteristic curve under partial shade. Potential power losses under partial shade are analyzed and divided into three parts respectively. Simulation results demonstrate that there are considerable power losses induced by PV module mismatch under determined tangible partial shade lasting for long time. Optimal configuration of BIPV array are brought forward to minimize PV module mismatch power loss for moving shade conditions, and it is also suitable to large desert or hillside PV power stations.

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17

Leghari, Zohaib Hussain, Mohammad Yusri Hassan, Dalila Mat Said, Laveet Kumar, Mahesh Kumar, Quynh T. Tran, and Eleonora Riva Sanseverino. "Effective Utilization of Distributed Power Sources under Power Mismatch Conditions in Islanded Distribution Networks." Energies 16, no. 6 (March 12, 2023): 2659. http://dx.doi.org/10.3390/en16062659.

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The integration of distributed generation (DG) into a power distribution network allows the establishment of a microgrid (MG) system when the main grid experiences a malfunction or is undergoing maintenance. In this case, the power-generating capacity of distributed generators may be less than the load demand. This study presents a strategy for the effective utilization of deployed active and reactive power sources under power mismatch conditions in the islanded distribution networks. Initially, the DGs’ and capacitors’ optimal placement and capacity were identified using the Jaya algorithm (JA) with the aim to reduce power losses in the grid-connected mode. Later, the DG and capacitor combination’s optimal power factor was determined to withstand the islanded distribution network’s highest possible power demand in the event of a power mismatch. To assess the optimal value of the DG–capacitor pair’s operating power factor (pfsource) for the islanded operation, an analytical approach has been proposed that determines the best trade-off between power losses and the under-utilization of accessible generation. The test results on 33-bus and 69-bus IEEE distribution networks demonstrate that holding the islanded network’s load power factor (pfload) equal to pfsource during the power imbalance conditions allows the installed distributed sources to effectively operate at full capacity. As expected, the proposed strategy will assist the utility companies in designing efficient energy management or load shedding schemes to effectively cope with the power mismatch conditions.

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Gull, Muhammad S., Nasir Mehmood, Huzaifa Rauf, Muhammad Khalid, and Naveed Arshad. "Soft Load Shedding Based Demand Control of Residential Consumers." Electronics 11, no. 4 (February 16, 2022): 615. http://dx.doi.org/10.3390/electronics11040615.

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Power generation and consumption is an instantaneous process and maintaining the balance between demand and supply is crucial since the demand and supply mismatch leads to various risks like over-investment, over-generation, under-generation, and the collapse of the power system. Therefore, the reduction in demand and supply mismatch is critical to ensure the safety and reliability of power system operation and economics. A typical and common approach, called full load shedding (FLS), is practiced in cases where electric power demand exceeds the available generation. FLS operation alleviates the power demand by cutting down the load for an entire area or region, which results in several challenges and problems for the utilities and consumers. In this study, a demand-side management (DSM) technique, called Soft-load shedding (SLS), is proposed, which uses data analytics and software-based architecture, and utilizes the real-world time-series energy consumption data available at one-minute granularity for a diversified group of residential consumers. The procedure is based on pattern identification extracted from the dataset and allocates a certain quota of power to be distributed on selected consumers such that the excessive demand is reduced, thereby minimizing the demand and supply mismatch. The results show that the proposed strategy obtains a significant reduction in the demand and supply mismatch such that the mismatch remains in the range of 10–15%, especially during the period where demand exceeds generation, operating within the utility constraints, and under the available generation, to avoid power system failure without affecting any lifeline consumer, with a minimum impact on the consumer’s comfort.

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19

Chang, Chun-Wei, Yi-Jan Emery Chen, and Jau-Horng Chen. "A Power-Recycling Technique for Improving Power Amplifier Efficiency Under Load Mismatch." IEEE Microwave and Wireless Components Letters 21, no. 10 (October 2011): 571–73. http://dx.doi.org/10.1109/lmwc.2011.2165535.

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20

Huang, Cheng Yang, Kazutaka Itako, Takeaki Mori, and Qiang Ge. "MPPT Control Method Using Boost Type DC-DC Converter for PV Generation System with Mismatched Modules." Advanced Materials Research 918 (April 2014): 171–76. http://dx.doi.org/10.4028/www.scientific.net/amr.918.171.

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Nowadays in a household PV generation system, it is generally connecting PV modules in series and then output to the power-conditioner. However, when PV modules are mismatched, it will lead to a wrong maximum power point tracking (MPPT) to all modules and a power decreasing of the whole system. Aiming at this problem, this paper presents the idea which improves the MPPT without changing the conventional power-conditioner, by adding a boost type DC-DC converter behind each module. Simulations of PSIM and experiments are taken to prove this theory. The result shows that, by this idea, the generated power of the conventional PV generation system can be greatly increased under the condition of mismatch.

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21

Nam, Jae-Hyeon, Sung-Hyun Park, Jin-Yeop Jang, and Sang-Gyu Park. "Mismatch-Shaping Switching Scheme for Split-Array Capacitive DACs." Electronics 12, no. 8 (April 17, 2023): 1891. http://dx.doi.org/10.3390/electronics12081891.

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Capacitive DACs (C-DACs) are widely used as stand-alone DACs or in an ADC as auxiliary DACs. An important performance metric of a C-DAC is its energy consumption and the linearity between the digital input and the analog output. In multi-bit C-DACs, the mismatch between the capacitors can degrade linearity, which can be important in high-resolution applications. In this work, we analyze the power consumption and linearity performance of a class of C-DACs called split-array C-DACs. We show that the simple element rotation technique, which is widely used to suppress the mismatch error of DACs, cannot be used with the power-efficient three-level switching scheme to effectively suppress the mismatch error. Then, we propose a switching scheme which can be used with the power efficient three-level switching and can suppress the in-band mismatch error effectively.

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22

Wang, Wei, Ping Yuan, and Yuru Yang. "The influence of mismatch between power and status on employee voice behavior." Social Behavior and Personality: an international journal 49, no. 9 (September 1, 2021): 1–14. http://dx.doi.org/10.2224/sbp.10552.

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The importance of research into voice behavior for organizational effectiveness has recently become even more evident. We explored the impact of the mismatch between power and status on employees' voice behavior through the mediating mechanism of power struggle and the moderating mechanism of power distance. Hypotheses were derived from legitimacy theory. Participants were 647 Chinese employee–supervisor dyads. We found that the mismatch between employees' sense of power and status positively predicted their voice behavior via power struggle, and the positive indirect relationship was amplified when power distance was at a higher level. Theoretical contributions and future research directions are discussed.

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23

Hensley, Max. "Power to the People: Why We Need Full Federal Preemption of Electrical Transmission Regulation." University of Michigan Journal of Law Reform, no. 46.4 (2013): 1361. http://dx.doi.org/10.36646/mjlr.46.4.power.

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State and federal governments have made significant investments in the development and installation of renewable energy technology. However, further increases in renewable power use have been stymied by the continued mismatch between the national interest in connecting consumers with utility-scale wind and solar installations and state and local control over the siting of electrical transmission lines. Because renewable power potential is often located far from consumers, transmission lines must cross multiple jurisdictions whose local interests have tended to prevent or significantly delay development. This Note analyzes that disconnect, reviews academic and legislative proposals to overcome it, and proposes a way for the federal government to preempt the states in order to streamline construction of the needed infrastructure while maintaining consideration of local concerns and advancing the overarching policy goal of shifting the electrical grid towards renewable power.

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Pathan, Erum, Afarulrazi Abu Bakar, Mubashir Hayat Khan, Muhammad Asad, and Haider Arshad. "Multiloop low bandwidth communication-based power sharing control for microgrids." Indonesian Journal of Electrical Engineering and Computer Science 21, no. 2 (February 1, 2020): 682. http://dx.doi.org/10.11591/ijeecs.v21.i2.pp682-690.

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<span>In parallel-connected inverter-based microgrids, the reactive power sharing accuracy can not have satisfactory results effortlessly. Mismatch in feeder impedances of the parallel-connected inverter-based microgrids is a significant cause of inaccurate reactive power-sharing. In voltage source inverters (VSI) based microgrids, especially for the islanded mode of operation, the conventional centralized or decentralized control techniques are not much helpful to control the voltage deviations due to impedance mismatch. Mismatch of the feeder impedance is compensated by the addition of fixed virtual impedance. Whereas, the change in the virtual impedance is compensated by adaptive virtual impedance-based control techniques which are helpful to mitigate power-sharing errors, but in most of the control schemes virtual impedance-based control mechanism needs pre-knowledge of feeder impedance which increases the computational burden. This paper presents a decentralized virtual impedance-based power sharing control. In the proposed control solution to mitigate reactive power sharing errors in distributed generation (DG) units, mismatch of the parallel-connected feeder impedance is equalized by regulating the addition of equivalent impedance to each DG inverter. Proposed control technique offers an independent implementation without any pre-knowledge of the feeder impedance. Hence, the implementation of the control scheme is a straightforward and computational burden is also reduced. Simulation results show the effectiveness of the control scheme. </span>

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Wang, Li, and Marshall Shibing Jiang. "Effect of power source mismatch on new venture performance." Chinese Management Studies 12, no. 4 (November 5, 2018): 833–46. http://dx.doi.org/10.1108/cms-07-2018-0589.

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PurposeThe venture capital syndication brings in various resources for the portfolio firms, which positively affects those firms’ performance, while conflicts within syndicates also have negative impact on the portfolio firms’ performance. This study aims to explore the two opposite effects of the venture capital syndication on the portfolio firms’ operations. Drawing on Ma et al.’s (2013) power source match perspective, the authors examine the effect of (mis)match of power source between ownership and status on the portfolio firms’ performance.Design/methodology/approachThe study uses panel data from two professional databases containing information about the venture capital-backed firms in China. The fixed effect model is applied to analyze the data.FindingsThis study found that power source match in the venture capital syndicates works positively on the portfolio firms’ performance. This positive relationship is weakened when there is ownership-dominated power source mismatch present.Practical implicationsThis study suggests that when new ventures search for venture capital, it is better to allocate greater ownership to the venture capital providers with high-status power, so that ownership power and status power can have a proper match to increase the coordination among venture capital providers, thereby helping portfolio firms perform better.Originality/valueThis study looks into the performance of a portfolio firm when there is power a (mis)match in a venture capital syndication, extending the current literature in this area where only the performance of the venture syndications is examined.

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Woolfrey, Ann E., John Klein, Michael D. Haagenson, Stephen R. Spellman, Minoo Battiwalla, James L. Gajewski, Gregory A. Hale, et al. "Evaluation of Human Leukocyte Antigen (HLA) Matching Requirements for Unrelated Peripheral Blood Stem Cell (PBSC) Transplantation." Blood 112, no. 11 (November 16, 2008): 563. http://dx.doi.org/10.1182/blood.v112.11.563.563.

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Abstract Criteria for the selection of HLA mismatched donors are needed when an HLA matched unrelated donor is not available. To define the risks associated with mismatching at HLA loci, and the impact of number of HLA mismatches on outcome, we studied 1933 patients receiving URD peripheral blood stem cell (PBSC) transplants facilitated by the National Marrow Donor Program between 1999–2006 for treatment of AML, ALL, CML or MDS. Myeloablative (65%) and reduced intensity (35%) regimens were included. The transplanted PBSC grafts were T cell-replete, and most patients received calcineurin-inhibitor based GVHD prophylaxis (99%) with T replete grafts. Median follow-up was 2 years. Pairs were typed for HLA-A, B, C, DRB1, DQA1 and DQB1 by high resolution typing methods. Matching was classified as low resolution (antigen-equivalent) or high resolution (allele) involving HLA-A, B, C, and DRB1 (8/8 match). Because of multiple comparisons, p-values <0.01 were considered significant. All analyses were adjusted for patient and transplant characteristics. Results: No effect of HLA-DQ mismatching was found for 8/8 or 7/8 matched transplant pairs, henceforth DQ mismatch was removed from subsequent models. Matching for 8/8 alleles was associated with better survival at one year (56% vs. 47%, p=0.001) compared with 7/8 matched pairs. Using patients with 8/8 match for comparison (n=1243), a single HLA-antigen mismatch (n=293) was associated with a significantly higher risk for overall mortality (OM), (relative risk (RR)=1.32, 95% confidence interval [CI] 1.12–1.55, p=0.0007), transplant-related mortality (TRM), (RR 1.54 [1.24–1.91] p=0.0001), grades III-IV graft-vs.-host disease (GVHD), (RR 1.93 [1.53–2.44] p<0.0001), and lower disease-free survival (DFS), (RR 1.29 [1.10–1.51] p=0.0013). No statistically significant decrement in survival was seen for those with a single (n=208) or double (n=28) HLA-allele mismatches involving HLA-A, B, C, and/or DRB1, although small sample size limits the power of the analysis. Two antigen or antigen plus allele mismatches [6/8 pairs] were associated with 2 to 3 times the risk for OM and TRM compared with 8/8 matched pairs, all p<0.001. Comparing 8/8 to 7/8 donor-recipient pairs mismatched at specific loci, only HLA-C antigen mismatches (n=187) were significantly associated with lower DFS (RR=1.36 [1.13–1.64] p=0.0010), and increased risk for OM (RR=1.41 [1.16–1.70], p=0.0005), TRM (RR=1.61 [1.25–2.08], p=0.0002), and GVHD grades III-IV (RR=1.98 [1.50–2.62], p<0.0001). No differences in outcome were observed for HLA-C allele mismatch (n=61), nor for mismatches at HLA-A antigen/allele (n=136), -B antigen/allele (n=73), -DRB1 allele (n=39) or -DQ antigen/allele (n=114) compared to 8/8 matching. HLA mismatching was not associated with relapse or chronic GVHD. Conclusion: These data suggest that when 8/8 matched PBSC donors are not available; HLA-C antigen mismatched donors should be avoided. The effects of HLA-mismatching in URD PBSC may be distinct from marrow transplants, although additional studies with larger numbers of patients may increase the power to detect effects of other specific locus mismatches.

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Aydin, Omer, Osman Palamutcuogullari, and Binboga Siddik Yarman. "Effect of input phase mismatch in Doherty power amplifiers." IEICE Electronics Express 13, no. 20 (2016): 20160870. http://dx.doi.org/10.1587/elex.13.20160870.

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Ito, Tomohiko, Takafumi Yamaji, Daisuke Kurose, and Tetsuro Itakura. "Capacitance Mismatch Evaluation for Low-power Pipeline ADC Design." IEICE Electronics Express 1, no. 3 (2004): 63–68. http://dx.doi.org/10.1587/elex.1.63.

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29

Grozdanovski, Jovancho, Rafael Mihalic, and Urban Rudez. "WAMS-Supported Power Mismatch Optimization for Secure Intentional Islanding." Energies 14, no. 10 (May 12, 2021): 2790. http://dx.doi.org/10.3390/en14102790.

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It is expected that a coordinated operation of several system integrity protection schemes will become a necessity in the future. This research represents an innovative strategy for coordinating under-frequency load shedding and intentional controlled islanding schemes for improving electric power system stability and resilience. In the great majority of real-world cases, both approaches follow conventional tactics, i.e., disconnecting a fixed number of feeders at predefined frequency thresholds and isolating a predefined area of a power system regardless of the actual conditions. Under the newly arisen network conditions in which weather-dependent distributed energy sources introduce a significant level of intermittency, conventional approaches need to be upgraded in order to retain a high level of power system operation security. In this paper, a mixed-integer linear programming approach is used to adjust the island size, including/excluding additional substations according to the available amount of generation in the region. The fine-tuning of the power rebalancing is achieved by potentially blocking selected load shedding stages. This minimizes the power imbalance of the newly formed islands, which helps to reduce the number of partial or even total blackouts and also accelerates the power system’s restoration process. The optimization approach was tested on a generic IEEE 39-bus network and shows promising results along with the capability of coping with real-world applications using wide-area monitoring systems as a source of real-time measurements. The results also indicated the importance of appropriate load modelling since both voltage and frequency dependence are recognized to have a significant effect on intentional controlled islanding.

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Bacher, R., and W. F. Tinney. "Faster Local Power Flow Solutions: The Zero Mismatch Approach." IEEE Power Engineering Review 9, no. 11 (1989): 32–33. http://dx.doi.org/10.1109/mper.1989.4310367.

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31

Ikram, Muhammad, Salman Ahmed, and Safdar Nawaz Khan Marwat. "Power Mismatch Estimation in Smart Grid Using Distributed Control." IEEE Access 8 (2020): 8798–811. http://dx.doi.org/10.1109/access.2019.2959827.

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32

Suarez, Almudena, Franco Ramirez, and Sergio Sancho. "Stability Analysis of Power Amplifiers Under Output Mismatch Effects." IEEE Transactions on Microwave Theory and Techniques 62, no. 10 (October 2014): 2273–89. http://dx.doi.org/10.1109/tmtt.2014.2344629.

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33

Picault, D., B. Raison, S. Bacha, J. de la Casa, and J. Aguilera. "Forecasting photovoltaic array power production subject to mismatch losses." Solar Energy 84, no. 7 (July 2010): 1301–9. http://dx.doi.org/10.1016/j.solener.2010.04.009.

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34

Li, Jiashuo, Kun Peng, Peng Wang, Ning Zhang, Kuishuang Feng, Dabo Guan, Jing Meng, Wendong Wei, and Qing Yang. "Critical Rare-Earth Elements Mismatch Global Wind-Power Ambitions." One Earth 3, no. 1 (July 2020): 116–25. http://dx.doi.org/10.1016/j.oneear.2020.06.009.

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35

Bacher, R., and W. F. Tinney. "Faster local power flow solutions: the zero mismatch approach." IEEE Transactions on Power Systems 4, no. 4 (1989): 1345–54. http://dx.doi.org/10.1109/59.41684.

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36

Suarez, Almudena, Franco Ramirez, and Sergio Sancho. "Generalized Stability Criteria for Power Amplifiers Under Mismatch Effects." IEEE Transactions on Microwave Theory and Techniques 63, no. 12 (December 2015): 4415–28. http://dx.doi.org/10.1109/tmtt.2015.2494578.

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37

Liu, Xiao, Ming Xie, Da Bo Li, and Jin Yuan Li. "A Method to Calculate the Net Power Delivered into a TEM Cell Using a Directional Coupler in a Probe Calibration Application." Applied Mechanics and Materials 475-476 (December 2013): 23–26. http://dx.doi.org/10.4028/www.scientific.net/amm.475-476.23.

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In a probe calibration facility employing the TEM cell as the field generator, a method to calculate the net power delivered into the TEM cell is presented through monitoring the coupling power of the directional coupler. The new formula requires the effective reflection coefficient of the dual coupler and takes into consideration the directivity of the coupler, the mismatch between the coupler and the TEM cell, the mismatch between the power sensor and the coupling port of the coupler. The formula can provide sufficient accuracy in calibration purpose application using a TEM cell with a coupler combined with power sensors to monitor the net power.

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38

Kakuda, Wataru, Maarten G. Lansberg, Vincent N. Thijs, Stephanie M. Kemp, Roland Bammer, Lawrence R. Wechsler, Michael E. Moseley, Michael P. Parks, and Gregory W. Albers. "Optimal Definition for PWI/DWI Mismatch in Acute Ischemic Stroke Patients." Journal of Cerebral Blood Flow & Metabolism 28, no. 5 (January 9, 2008): 887–91. http://dx.doi.org/10.1038/sj.jcbfm.9600604.

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Although the perfusion-weighted imaging/diffusion-weighted imaging (PWI/DWI) mismatch model has been proposed to identify acute stroke patients who benefit from reperfusion therapy, the optimal definition of a mismatch is uncertain. We evaluated the odds ratio for a favorable clinical response in mismatch patients with reperfusion compared with no reperfusion for various mismatch ratio thresholds in patients enrolled in the diffusion and perfusion imaging evaluation for understanding stroke evolution (DEFUSE) study. A mismatch ratio of 2.6 provided the highest sensitivity (90%) and specificity (83%) for identifying patients in whom reperfusion was associated with a favorable response. Defining mismatch with a larger PWI/DWI ratio may provide greater power for detecting beneficial effects of reperfusion.

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39

Ji, Xinzhe, Kangwen Sun, Xiao Guo, and Mou Sun. "Energy Acquisition of Solar-Powered Joint-Wing Aircraft Considering Mismatch Power Loss." Energies 15, no. 1 (December 27, 2021): 157. http://dx.doi.org/10.3390/en15010157.

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Solar-powered aircraft can perform long-term flights with clean solar energy. However, the energy derived from solar irradiation is influenced by the time of year and latitude, which limits the energy acquisition ability of solar aircraft with a straight-wing configuration. Hence, unconventional configurations based on increasing wing dihedral to track the sun are proposed to improve energy acquisition at high-latitude regions in winter, which may involve power loss caused by mismatch in the photovoltaic system. However, mismatch loss is seldom considered and may cause energy to be overestimated. In this paper, the energy acquisition characteristics of a joint-wing configuration are presented based on the simulation of an energy system to investigate the mismatch power loss. The results indicate a 4~15% deviation from the frequently used estimation method and show that the mismatch loss is influenced by the curved upper surface, the severity of shading and the circuit configuration. Then, the configuration energy acquisition factor is proposed to represent the energy acquisition ability of the joint-wing configuration. Finally, the matching between the aircraft configuration and flight trajectory is analyzed, demonstrating that the solar-powered aircraft with an unconventional wing configuration is more sensitive to the coupling between configuration and trajectory.

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Shah, M., and S. Gupta. "Baseband I/Q regeneration Method for Direct Conversion Receiver to nullify effect of I/Q mismatch." Advanced Electromagnetics 5, no. 3 (November 17, 2016): 50. http://dx.doi.org/10.7716/aem.v5i3.435.

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Direct Conversion Receiver is the choice of the today’s designer for low power compact wireless receiver. DCR is attractive due to low power, small size and highly monolithic integratable structure, but distortions affect its performance. I/Q mismatch is the one of the major distortion which is responsible for performance degradation. In this paper, a novel method for Direct Conversion Receiver is suggested, which makes it insensitive to the I/Q mismatch. Here the classical homodyne architecture is modified to nullify effect of I/Q mismatch. The proposed method can be implemented in the Digital Signal Processing (DSP) back-end section also. This feature makes it acceptable in the already designed/functioning classical homodyne architecture based receiver.

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41

Jeon, Jung, and Kang. "Software-Based Adaptive Protection Control Against Load Mismatch for a Mobile Power Amplifier Module." Electronics 8, no. 11 (October 27, 2019): 1226. http://dx.doi.org/10.3390/electronics8111226.

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A closed-loop protection method for a radio frequency (RF) power amplifier (PA) module applicable to mobile handsets has been introduced. The load impedance of the PA was adaptively sensed by an embedded impedance detector which was digitally controlled and the system adjusted PA power using a feedback circuit to keep the PA safe based on a load mismatch detection. For verification, a two-stage hetero junction bipolar transistor (HBT) PA module for handsets was fabricated and tested against load mismatch. Measurement results showed that the technique could help PA survive at a 0.5V larger collector bias voltage condition than when the technique was not applied for the same mismatch condition with an acceptable RF performance degradation at nominal condition.

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Keddar, Mohamed, Mamadou Lamine Doumbia, Karim Belmokhtar, and Mohamed Della Krachai. "Enhanced Reactive Power Sharing and Voltage Restoration Based on Adaptive Virtual Impedance and Consensus Algorithm." Energies 15, no. 10 (May 10, 2022): 3480. http://dx.doi.org/10.3390/en15103480.

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In this paper, power-sharing management control on an AC islanded microgrid is investigated to achieve accurate reactive power sharing. The droop control method is primarily used to manage the active and reactive power sharing among the DGs in the microgrid. However, the line impedance mismatch causes unbalanced reactive power sharing. As a solution a consensus-based adaptive virtual impedance controller is proposed, where the consensus algorithm is used to set the reactive power mismatch; then a virtual impedance correction term is generated through a proportional-integral controller to eliminate the line impedance mismatch. Thus, reactive power sharing is achieved without knowledge of the line impedances or using a central controller. Moreover, the consensus algorithm is used to restore the AC bus voltage to the nominal value by estimating the DGs average voltage using neighbor communication to compensate for the decreased magnitude of the voltage reference. Matlab/Simulink is used to validate the accuracy of reactive power sharing and voltage restauration achievement of the proposed solution through simulation of different scenarios. In addition, a dSPACE DS1104 is used within a developed experimental testbench based on two parallel DGs to validate the effectiveness of the proposed solution in the real world.

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43

Welz, J., and I. Galton. "A Tight Signal-Band Power Bound on Mismatch Noise in a Mismatch-Shaping Digital-to-Analog Converter." IEEE Transactions on Information Theory 50, no. 4 (April 2004): 593–607. http://dx.doi.org/10.1109/tit.2004.825022.

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44

Saeed, Faisal, Haider Ali Tauqeer, Hasan Erteza Gelani, Muhammad Hassan Yousuf, and Asad Idrees. "Numerical modeling, simulation and evaluation of conventional and hybrid photovoltaic modules interconnection configurations under partial shading conditions." EPJ Photovoltaics 13 (2022): 10. http://dx.doi.org/10.1051/epjpv/2022004.

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Partial shading on solar photovoltaic (PV) arrays is a prevalent problem in photovoltaic systems that impair the performance of PV modules and is responsible for reduced power output as compared to that in standard irradiance conditions thereby resulting in the appearance of multiple maximas on panel output power characteristics. These maxims contribute to mismatch power losses among PV modules. The mismatch losses depend on shading characteristics together with different interconnected configuration schemes of PV modules. The research presents a comparative analysis of partial shading effects on a 4 × 4 PV array system connected in series (S), parallel (P), serries-parallel (SP), total-cross-tied (TCT), central-cross-tied (CCT), bridge-linked (BL), bridge-linked total cross-tied (BLTCT), honey-comb (HC), honey-comb total-cross-tied (HCTCT) and ladder (LD) configurations using MATLAB/Simulink. The PV module SPR-X20-250-BLK was used for modeling and simulation analysis. Each module is comprised of 72 number of PV cells and a combination of 16 PV modules was employed for the contextual analysis. Accurate mathematical modeling for the HCTCT configuration under partial shading conditions (PSCs) is provided for the first time and is verified from the simulation. The different configuration schemes were investigated under short-narrow, short-wide, long-narrow, long-wide, diagonal, entire row distribution, and entire column distribution partial shading condition patterns with mathematical implementation and simulation of passing clouds. The performance of array configurations is compared in terms of maximum power generated (Pmp), mismatch power loss (ΔPml), relative power loss (Prl) and the fill factor (FF). It was inferred that on average, TCT configuration yielded maximum power generation under all shading patterns among all PV modules interconnection configurations with minimum mismatch power losses followed by hybrid and conventional PV array configurations respectively.

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45

Palmer, Michael J., R. Wayne Johnson, Mohammad Motalab, Jeffrey Suhling, and James D. Scofield. "Development of a Silicon Nitride High Temperature Power Module." Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2011, HITEN (January 1, 2011): 000172–79. http://dx.doi.org/10.4071/hiten-paper7-rwjohnson.

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Silicon nitride (Si3N4) offer potential advantages as a substrate for high temperature power packaging. Si3N4 has higher fracture strength than alumina and aluminum nitride. The coefficient of thermal expansion (CTE) of Si3N4 is ~3 ppm/°C and the thermal conductivity ranges from 30–50W/m-K. Active metal brazed Cu-Si3N4 substrates are commercially available for power modules. However, the large mismatch in CTE between Si3N4 and Cu results in ceramic fracture and delamination with the wide temperature thermal cycling ranges encountered in high temperature applications. In this work Cu-Carbon and Cu-Mo metal matrix composites have been investigated to reduce the CTE mismatch. The process details are presented along with finite element modeling of the proposed structure. Ultimately, the proposed structure was unsuccessful.

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46

Duan, Yanliang, Yanping Gong, Xiaohui Yang, and Weiping Cao. "Oblique Projection-Based Covariance Matrix Reconstruction and Steering Vector Estimation for Robust Adaptive Beamforming." Electronics 11, no. 21 (October 26, 2022): 3478. http://dx.doi.org/10.3390/electronics11213478.

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Adaptive beamforming can efficiently contract interference and noise. Due to high sensitivity of the beamformer to model mismatch, the capability of interference reduction will critically degrade when the signal model mismatch occurs, particularly when the sampling sequence contains the desired signal. For the purpose of enhancing the robustness of beamformers to signal model mismatch, we propose a new robust adaptive beamforming (RAB) method. Firstly, the precise steering vector (SV) associating with the desired signal is estimated by employing the minimum norm of subspace projection (MNSP) approach. Secondly, the nominal interference SVs are estimated via the maximum entropy power spectrum. Subsequently, the corrected interference SVs and powers are obtained by oblique projection. Finally, the interference-plus-noise covariance matrix (INCM) is reconstructed, and the proposed RAB is obtained. Multiple simulations are carried out and demonstrate the robustness of the proposed RAB method.

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47

Paul, Rajarshi, Luke Sankey, Luca Corradini, Zoya Popovic, and Dragan Maksimovic. "Power Management of Wideband Code Division Multiple Access RF Power Amplifiers With Antenna Mismatch." IEEE Transactions on Power Electronics 25, no. 4 (April 2010): 981–91. http://dx.doi.org/10.1109/tpel.2009.2036355.

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48

MILLAR, Benjamin S., and Danchi JIANG. "Asynchronous consensus for optimal power flow control in smart grid with zero power mismatch." Journal of Modern Power Systems and Clean Energy 6, no. 3 (March 8, 2018): 412–22. http://dx.doi.org/10.1007/s40565-018-0378-4.

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49

Tejaswini, K. Naga, and G. Kesava Rao. "Consensus Based Economic Dispatch including System Power Losses." International Journal of Engineering & Technology 7, no. 1.8 (February 9, 2018): 178. http://dx.doi.org/10.14419/ijet.v7i1.8.11545.

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Economic dispatch (ED) is an important class of optimization problem in Power System Operation. As both conventional and heuristic methods to solve EDP are centrally controlled, which may leads to some performance limitations, a Consensus based distributed algorithm is proposed in this paper to solve Economic Dispatch with inclusion of losses. Earlier, some papers dealt with the consensus based methods to solve Economic dispatch, but here in this paper the losses are included and the variation of losses at each iteration are also used to update the mismatch, which has some major prominence in the present day Power system environment. In this paper, the mismatch between load demand and total power generation is collectively learnt by the each generator, unlike the centralized approach, through the strongly connected communication network. MATLAB results in IEEE 6-bus system validate the potency and efficacy of the proposed technique

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Oluyomi Ajibade, Adedayo, llesanmi Banjo Oluwafemi, and Israel Esan Owolabi. "Characterisation of Signal Amplitude-Frequency for Indoor Power Line Communication Channel in the 1 — 30 MHz Broadband Frequencies." International journal of electrical and computer engineering systems 12, no. 1 (April 21, 2021): 33–41. http://dx.doi.org/10.32985/ijeces.12.1.4.

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The transmission of data signals over power lines is a very promising technique for delivering indoor broadband communication services. However, since power grids were originally designed for high-voltage low-frequency signal transmission, there is a frequency mismatch between the power grid and high-frequency data signals. This mismatch poses a challenge to deploying power lines as a communication channel. Although, studies and researches conducted in several countries have made transmission of data over power lines possible, the behaviour and properties of the power grid cannot be generalised. Hence, the need for in-depth experiment and measurement on the suitability and capability of the Nigerian power grid for data transmission is crucial for proper characterising and modelling of the power line communication (PLC) channel. In this paper, we present experimental measurements and results of the effects of frequency variations on the attenuation experienced by broadband high-speed data signals transmitted over the Nigerian indoor power line network.

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