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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 958-970页

作者： Jialiang Wu Zhen Wang Ruixu Liu Yu Shan Chenxuan Wang the co.lege of electrical engineering Zhejiang University IEEE the Eco.omic Research Institute of State Grid zhejiang Electric Power co. Ltd.

Hybrid multi-terminal direct current(MTDC) transmission technology has been a research focus, and primary frequency regulation(FR) improvement in the receiving-end system is one of the problems to be solved. This paper presents a decentralized primary FR scheme for hybrid MTDC power systems co.sidering multi-source enhancement to help suppress frequency disturbance in the receiving-end systems. All the co.verters only need local frequency or DC voltage signal input to respond to system disturbance without co.munication or a co.trol center, i. e., a decentralized co.trol scheme. The proposed scheme can activate appropriate power sources to assist in FR in various system disturbance severities with fine-designed thresholds, ensuring sufficient utilization of each power source. To better balance FR performance and FR resource participation, an evaluation index is proposed and the parameter optimization problem is further co.ducted. Finally, the validity of the proposed scheme is verified by simulations in MATLAB/Simulink.

关键词： Frequency co.trol HVDC transmission Voltage co.trol Hybrid power systems Frequency co.version Voltage measurement Power system stability

Partition-based Network Equivalent Method for Power System Subsynchronous Oscillation Analysis

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 313-320页

作者： Chenxuan Wang Weimin Zheng Zhen Wang Yangqing Dan Ping Ju the Department of electrical engineering Zhejiang UniversityHangzhou 310027China the Eco.omic Research Institute of State Grid zhejiang Electric Power co. Ltd.Hangzhou 310016China the co.lege of Energy and electrical engineering Hohai UniverstiyNanjing 211100China

Given large-scale modern power systems with pow er electronic co.verters,the numerical simulation with subsyn chronous oscillation(SSO)faces great challenges in engineering practice due to sharply enlarged modeling scale and high co. putational burden.To reduce the modeling scale,network parti tion and equivalent beco.es a vital technique in numerical sim ulations.Although several methods have been developed for net work equivalent,a generally accepted rule for network parti tion is still required.This paper proposes that the system can be partitioned into three parts,i.e.,the internal,the middle,and the external subsystems,in which the internal subsystem co.sists of all power electronic co.ponents,the middle subsys tem includes those selected AC dynamic co.ponents with de tailed models,and the remaining co.ponents and buses co.sti tute the external subsystem.The external subsystem is further represented by an equivalent RLC network determined by the frequency dependent network equivalent(FDNE)method.In the proposed method,the observability index and the electrical distance index are used to identify the interface between the middle and the external subsystems.Case studies based on a modified Hydro-Quebec system are used to verify the effective ness of the proposed method.

关键词： electrical distance network equivalent subsyn chronous oscillation observability index

Tube Model Predictive co.trol Based Cyber-attack-resilient Optimal Voltage co.trol Strategy in Wind Farms

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 530-538页

作者： Zhenming Li Minghao Wang Yunfeng Yan Donglian Qi Zhao Xu Jianliang Zhang Zezhou Wang co.lege of electrical Electronic engineering Zhejiang UniversityHangzhou 310058China Department of electrical engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina Haiyan power supply co.pany of State Grid zhejiang Electric Power co. LtdHangzhouChina

Optimal voltage co.trols have been widely applied in wind farms to maintain voltage stability of power grids.In order to achieve optimal voltage operation,authentic grid information is widely needed in the sensing and actuating processes.However,this may induce system vulnerable to malicious cyber-attacks.To this end,a tube model predictive co.trol-based cyber-attack-resilient optimal voltage co.trol method is proposed to achieve voltage stability against malicious cyber-attacks.The proposed method co.sists of two cascaded model predictive co.trollers(MPC),which outperform other peer co.trol methods in effective alleviation of adverse effects from cyber-attacks on actuators and sensors of the system.Finally,efficiency of the proposed method is evaluated in sensor and actuator cyber-attack cases based on a modified IEEE 14 buses system and IEEE 118 buses system.Index Terms-Attack-resilient co.trol,optimal voltage co.trol,tube-based model predictive co.trol,wind farm-co.nected power system.

关键词： Attack-resilient co.trol optimal voltage co.trol tube-based model predictive co.trol wind farm-co.nected power system

Reliability evaluation of IGBT power module on electric vehicle using big data

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Journal of Semico.ductors 2024年第5期45卷 50-60页

作者： Li Liu Lei Tang Huaping Jiang Fanyi Wei Zonghua Li Changhong Du Qianlei Peng Guocheng Lu The School of electrical engineering Chongqing UniversityChongqing 400044China The Deepal Automobile Technology co. Ltd.Chongqing 400023China

There are challenges to the reliability evaluation for insulated gate bipolar transistors(IGBT)on electric vehicles,such as junction temperature measurement,co.putational and storage resources.In this paper,a junction temperature estimation approach based on neural network without additional co.t is proposed and the lifetime calculation for IGBT using electric vehicle big data is performed.The direct current(DC)voltage,operation current,switching frequency,negative thermal co.fficient thermistor(NTC)temperature and IGBT lifetime are inputs.And the junction temperature(T_(j))is output.With the rain flow co.nting method,the classified irregular temperatures are brought into the life model for the failure cycles.The fatigue accumulation method is then used to calculate the IGBT lifetime.To solve the limited co.putational and storage resources of electric vehicle co.trollers,the operation of IGBT lifetime calculation is running on a big data platform.The lifetime is then transmitted wirelessly to electric vehicles as input for neural network.Thus the junction temperature of IGBT under long-term operating co.ditions can be accurately estimated.A test platform of the motor co.troller co.bined with the vehicle big data server is built for the IGBT accelerated aging test.Subsequently,the IGBT lifetime predictions are derived from the junction temperature estimation by the neural network method and the thermal network method.The experiment shows that the lifetime prediction based on a neural network with big data demonstrates a higher accuracy than that of the thermal network,which improves the reliability evaluation of system.

关键词： IGBT junction temperature neural network electric vehicles big data

Exploiting demand-side heterogeneous flexible resources in risk management of power system frequency

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Science China(Technological Sciences) 2024年第5期67卷 1612-1627页

作者： YAO Yu SONG YongHua YE ChengJin DING Yi ZHAO YuMing co.lege of electrical engineering Zhejiang UniversityHangzhou310027China State Key Laboratory of Internet of Things for Smart City University of MacaoMacao SAR519000China Shenzhen Power Supply Bureau co. Ltd.Shenzhen518051China

More demand-side flexible resources(DFRs)are participating in the frequency regulation of renewable power systems,whose heterogeneous characteristics have a significant impact on the system frequency response.co.sequently,selecting suitable DFRs poses a formidable challenge for independent system operators(ISO).In this paper,a reserve allocation methodology for heterogeneous DFRs is proposed to manage the risk of power system frequency.Firstly,a performance curve is developed to describe the co.t,capacity,and response speed of DFRs.Moreover,a clustering method for multiple distributed DFRs is co.ducted to calculate the aggregated performance curves and uncertainty co.fficients.Then,the frequency security criterion co.sidering DFRs’performance is co.structed,whose linearity makes it can be easily co.pled into the system scheduling model and solved.Furthermore,a risk management model for DFRs co.sidering frequency-chance-co.straint is proposed to make a trade-off between co.t and frequency security.Finally,the model is transformed into mixed integer seco.d-order co.e programming(MISOCP)and solved by the co.mercial solver.The proposed model is validated by the IEEE 30 and IEEE 118 bus systems.

关键词： demand-side heterogenous flexible resources risk management of power system frequency performance curve aggregation method mixed integer seco.d-order co.e programming

Experimental and numerical study on atmospheric-pressure air dielectric barrier discharge via 50 Hz/5000 Hz dual-frequency excitation

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High Voltage 2024年第2期9卷 391-402页

作者： Junwen He Bangfa Peng Guanglin Yu Ronggang Wang Nan Jiang Jie Li Yan Wu School of electrical engineering Dalian University of TechnologyDalianChina Canmax Technologies co. Ltd.SuzhouChina

A dual-frequency(DF)dielectric barrier discharge,excited by the superposition of a 50 Hz low frequency(LF)and a 5000 Hz intermediate frequency(IF),is proposed to enhance discharge.The effect of the LF voltage co.ponent on the breakdown behaviour of the DF discharge during different periods has been studied both experimentally and numerically.The number of high-current pulses rises as the LF voltage increases.The statistical analysis shows that the number of the current pulse amplitude above 80 mA in the DF discharge reaches nearly 6 times that in the IF discharge.Additionally,the total discharge energy in the DF discharge is significantly higher than that in the IF discharge.The simulation re-produces the temporal variation of the breakdown behaviours in the DF discharge.The simulated results reveal that the maximal electric field strength of the breakdown process is greater in the DF discharge co.pared to the IF discharge during a half-period of DF.Finally,the co.parison between the IF and DF discharges exhibits that the LF voltage regulates the accumulation of residual charged species on the dielectric surface after the breakdown by modulating the residual voltage between the air gap.

关键词： dielectric excitation excited

Flow Boiling Heat Transfer Characteristics and Delayed Dry-Out Ability of Non-Azeotropic Mixtures R245fa/R134a in Microchannels

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Journal of Thermal Science 2024年第3期33卷 1174-1188页

作者： LU Yongjie LING Yongjun ZHUANG Yuan LI Chenyang OUYANG Hongsheng HAN Xiaohong Key Laboratory of Refrigeration and Cryogenic Technology of zhejiang Province Institute of Refrigeration and CryogenicsZhejiang UniversityHangzhou310007China zhejiang Zhongguang electrical co. Ltd.Lishui323000China State Key Lab for Fluorine Greenhouse Gases Replacement and co.trol Treatment Zhejiang Research Institute of Chemical IndustryHangzhou310014China

Microchannel flow boiling heat transfer has the advantages of strong heat dissipation capacity,good temperature uniformity,and co.pact structure.It is an excellent way to thermally manage electronic devices,but when the heat flux exceeds CHF(Critical Heat Flux),the heat transfer performance deteriorates as the working fluid dries out.Non-azeotropic mixtures have the potential to effectively delay or avoid dry-out during the boiling process due to their temperature slide characteristics which causes the mass transfer resistance.To understand the influence of non-azeotropic mixtures on microchannel flow boiling,using the phase-change microchannel heat sink as the research object,the experiments on the flow boiling heat transfer performance of R245fa/R134a mixtures under different working co.ditions were carried out,and the characteristics of flow boiling heat transfer were obtained under the different working co.ditions,and co.parison was developed with those of pure substance R245fa.The results demonstrated that a small amount of low-boiling-point co.ponents in the high-boiling-point working fluid inhibited boiling heat transfer to some extent,and lowered the average heat transfer co.fficient under the non-dryout co.dition slightly lower than that of the pure substance;however,it also effectively delayed the onset of local dry-out and prevented significant deterioration in thermal transfer performance under the lower mass flow rate and higher heat flux,which co.ld enhance the heat sink's stability.

关键词： microchannel flow boiling non-azeotropic mixture heat transfer characteristics dry-out

Distributed Photovoltaic Real-Time Output Estimation Based on Graph co.volutional Networks

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Journal of Shanghai Jiaotong university(Science) 2024年第2期29卷 290-296页

作者：陈利跃洪道鉴何星卢东祁张乾谢妮娜徐一洲应煌浩 State Grid zhejiang Electric Power co. Ltd.Hangzhou 310007China State Grid zhejiang Taizhou Power Supply co.pany Taizhou 318000ZhejiangChina Department of Automation School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The rapid growth of distributed photovoltaic(PV)has remarkable influence for the safe and eco.omic operation of power systems.In view of the wide geographical distribution and a large number of distributed PV power stations,the current situation is that it is dificult to access the current dispatch data network.Acco.ding to the temporal and spatial characteristics of distributed PV,a graph co.volution algorithm based on adaptive learning of adjacency matrix is proposed to estimate the real-time output of distributed PV in regional power grid.The actual case study shows that the adaptive graph co.volution model gives different adjacency matrixes for different PV stations,which makes the co.responding output estimation algorithm have higher accuracy.

关键词： distributed photovoltaic(PV) graph co.volution network power estimation

Mechanism Design for Ancillary Service Market co.sidering Social Welfare and Fairness

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1000-1010页

作者： Zhi Wu Yuanxi Wu Wei Gu Zheng Xu Shu Zheng Jingtao Zhao School of electrical engineering Southeast UniversityNanjing 210096China NARI Technology co. Ltd.Nanjing 211106China IEEE CSEE

Increasing penetration of distributed energy resources in the distribution network(DN)is threatening safe operation of the DN,which necessitates setup of the ancillary service market in the DN.In the ancillary service market,distribution system operator(DSO)is responsible for safety of the DN by procuring available capacities of aggregators.Unlike existing studies,this paper proposes a novel market mechanism co.posed of two parts:choice rule and payment rule.The proposed choice rule simultaneously co.siders social welfare and fairness,enco.raging risk-averse aggregators to participate in the ancillary service market.It is then formulated as a linear programming problem,and a distributed solution using the multi-cut Benders deco.position is presented.Moreover,successful implementation of the choice rule depends on each aggregator’s truthful adoption of private parameters.Therefore,a payment rule is also designed,which is proved to possess two properties:incentive co.patibility and individual rationality.Simulation results demonstrate effectiveness of the proposed choice rule on improving fairness and verify properties of the payment rule.

关键词： Aggregator ancillary service market distributed mechanism fairness mechanism design

Mechanism of action, benefits, and research gap in fermented soybean meal utilization as a high-quality protein source for livestock and poultry

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Animal Nutrition 2024年第1期16卷 130-146页

作者： Modinat T.Lambo Haokai Ma Haosheng Zhang Peng Song Hongxiang Mao Guowen Cui Baisheng Dai Yang Li Yonggen Zhang co.lege of Animal Science and Technology Northeast Agricultural University Wilmar (Shanghai) Biotechnology Research and Development Center co. Ltd co.lege of electrical engineering and Information Northeast Agricultural University

Animal nutritionists have incessantly worked towards providing livestock with high-quality plant protein feed resources.Soybean meal (SBM) has been an essential and predominantly adopted vegetable protein source in livestock feeding for a long time;however,several SBM antinutrients co.ld potentially impair the animal's performance and growth,limiting its use.Several processing methods have been employed to remove SBM antinutrients,including fermentation with fungal or bacterial microorganisms.Acco.ding to the literature,fermentation,a traditional food processing method,co.ld improve SBM's nutritional and functional properties,making it more suitable and beneficial to livestock.The current interest in health-promoting functional feed,which can enhance the growth of animals,improve their immune system,and promote physiological benefits more than co.ventional feed,co.pled with the ban on the use of antimicrobial growth promoters,has caused a renewed interest in the use of fermented SBM (FSBM) in livestock diets.This review details the mechanism of SBM fermentation and its impacts on animal health and discusses the recent trend in the application and emerging advantages to livestock while shedding light on the research gap that needs to be critically addressed in future studies.FSBM appears to be a multifunctional high-quality plant protein source for animals.Besides removing soybean antinutrients,beneficial bioactive peptides and digestive enzymes are produced during fermentation,providing probiotics,antioxidants,and immunomodulatory effects.Critical aspects regarding FSBM feeding to animals remain uncharted,such as the duration of fermentation,the influence of feeding on digestive tissue development,choice of microbial strain,and possible environmental impact.

关键词： Soybean meal Protein feed Fermentation Microorganism Livestock