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Optimization of Generator Based on Gaussian Process Regression Model with Conditional Likelihood Lower Bound Search

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 32-42页

作者： Xiao Liu Pingting Lin Fan Bu Shaoling Zhuang shoudao huang CES&IEEE the College of Electrical and Information Engineering Hunan UniversityChangsha 410082China CES

The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of ***,this paper proposes a Gaussian Process Regression(GPR)model based on Conditional Likelihood Lower Bound Search(CLLBS)to optimize the design of the generator,which can filter the noise in the data and search for global optimization by combining the Conditional Likelihood Lower Bound Search *** the efficiency optimization of 15 kW Permanent Magnet Synchronous Motor as an ***,this method uses the elementary effect analysis to choose the sensitive variables,combining the evolutionary algorithm to design the super Latin cube sampling plan;Then the generator-converter system is simulated by establishing a co-simulation platform to obtain data.A Gaussian process regression model combing the method of the conditional likelihood lower bound search is established,which combined the chi-square test to optimize the accuracy of the model ***,after the model reaches the accuracy,the Pareto frontier is obtained through the NSGA-II algorithm by considering the maximum output torque as a ***,the constrained optimization is transformed into an unconstrained optimizing problem by introducing maximum constrained improvement expectation(CEI)optimization method based on the re-interpolation model,which cross-validated the optimization results of the Gaussian process regression *** above method increase the efficiency of generator by 0.76%and 0.5%respectively;And this method can be used for rapid modeling and multi-objective optimization of generator systems.

关键词： Generator optimization Gaussian Process Regression(GPR) Conditional Likelihood Lower Bound Search(CLLBS) Constraint improvement expectation(CEI) Finite element calculation

Significantly enhanced varistor properties of CaCu_(3)Ti_(4)O_(12) based ceramics by designing superior grain boundary:Deepening and broadening interface states

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Journal of Materials Science & Technology 2022年第13期108卷 82-89页

作者： Zhuang Tang Kai Ning Zhiyao Fu Ze Lian Kangning Wu shoudao huang State Key Laboratory of Disaster Prevention and Reduction for Power Grid Transmission and Distribution Equipment SGCC(State Grid Corporation of China)Changsha 410000China College of Electrical and Information Engineering Hunan UniversityChangsha 410082China State Grid Shanxi Electric Power Research Institute Taiyuan 030001China State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityXi’an 710049China

Significantly enhanced varistor properties via tailoring interface states were obtained in Ca_(1-2x/3)Y_(x)Cu_(3)Ti_(4)O_(12)-SrCu_(3)Ti_(4)O_(12) composite *** breakdown field was improved to 35.8 kV cm^(-1) and the nonlinear coefficient in 0.1-1 mA cm^(-2) was enhanced to 14.6 for Ca_(0.67)Y_(0.5)Cu_(3)Ti_(4)O_(12)-SrCu_(3)Ti_(4)O_(12).Noticeably,the withstand voltage of single grain boundary reached up to 24 V while the reported ones were constant to about 3 *** improved properties were attributed to the formation of superior grain boundary rather than the reduced grain ***,with distinct discrepancy of nonlinear performance in the composites,the resistance and activation energy of grain boundary exhibited little *** on the double Schottky barrier at grain boundary and the field-assisted thermal emission model,it was found that the excellent electrical nonlinearity arose from the formation of deeper and broader interface states at grain *** this case,interface states were not easily entirely filled and the barrier could maintain its height under applied *** work provides a novel routine for enhancing the varistor properties of CaCu_(3)Ti_(4)O_(12) based ceramics by manipulating interface states at grain boundary.

关键词： Schottky barrier Grain boundary Varistor ceramics Interface states

Optimal Design for Wireless Power Transfer System with Relay Resonators

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Journal of Donghua University(English Edition) 2018年第4期35卷 302-308页

作者： CHEN Xin huang shoudao College of Electrical and Information Engineering Hunan UniversityChangsha 410082China Uniuersity of Humanities Science and TechnologyLoudi 417000China

The optimization method by adjusting load and distances between two adjacent coils( or resonators) is presented on basis of wireless power transfer( WPT) system with relay resonators. 2-port network and impedance matching theory are applied to analyzing power flow of incidence and reflection in WPT system,then setting up power flow model. The maximum power transmission efficiency can be obtained when the load and distance between secondary resonator and output coil meets impedance matching at 2-port network's output port. The simulation and experimental results shown the impedance matching method can effectively improve and maintain transmission efficiency by adjusting load and distances between coils or relay resonators.

关键词： wireless power transfer relay resonators 2-port network impedance matching power flow model

A Power Allocation Method for Grid-Connected MMC Inverter Based on Droop Control

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Chinese Journal of Electrical Engineering 2016年第2期2卷 84-91页

作者： Fei Rong Zhangtao Yin Zhikang Shuai shoudao huang College of Electrical and Information Engineering Hunan UniversityChangsha410082China

Droop control has been widely used for controlling distributed *** capacity of the MMC inverter may be insufficient,a power allocation method for grid-connected MMC inverter based on droop control is presented to improve the stability of the power *** there is potential for large disturbances in the power grid,an equal speed regulation strategy is adopted to make the speed of the voltage collapse be the same as the frequency *** obtaining the active and reactive power references of MMC inverter according to equal speed regulation strategy,the deadbeat control method is calculated using these power references and adopted to track the reference *** Routh criterion is used to analyze the influence of the inductance measurement error on the control ***,a simulation model is established with Matlab and *** simulation results show that the stability of the power grid has been improved with the proposed control method.

关键词： MMC droop control power allocation equal speed regulation deadbeat control

Overview of condition monitoring and operation control of electric power conversion systems in direct-drive wind turbines under faults

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Frontiers of Mechanical Engineering 2017年第3期12卷 281-302页

作者： shoudao huang Xuan WU Xiao LIU Jian GAO Yunze HE College of Electrical and Information Engineering Hunan University Changsha 410082 China

Electric power conversion system （EPCS）, which consists of a generator and power converter, is one of the most important subsystems in a direct-drive wind turbine （DD-WT）. However, this component accounts for the most failures （approximately 60% of the total number） in the entire DD-WT system according to statistical data. To improve the reliability of EPCSs and reduce the operation and maintenance cost of DD-WTs, numerous researchers have studied condition monitoring （CM） and fault diagnostics （FD）. Numerous CM and FD techniques, which have respective advantages and disadvantages, have emerged. This paper provides an overview of the CM, FD, and operation control of EPCSs in DD-WTs under faults. After introducing the functional principle and structure of EPCS, this survey discusses the common failures in wind generators and power converters; briefly reviewed CM and FD methods and operation control of these generators and power converters under faults; and discussed the grid voltage faults related to EPCSs in DD-WTs. These theories and their related technical concepts are systematically discussed. Finally, predicted development trends are presented. The paper provides a valuable reference for developing service quality evaluation methods and fault operation control systems to achieve high-performance and high-intelligence DD-WTs.

关键词： direct-drive wind turbine electric power conversion system condition monitoring fault diagnosis,operation control under faults fault tolerance

Analysis of a Novel Mechanically Adjusted Variable Flux Permanent Magnet Homopolar Inductor Machine with Rotating Magnetic Poles for Flywheel Energy Storage System

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CES Transactions on Electrical Machines and Systems 2022年第3期6卷 315-323页

作者： Qing Li Mingcheng Lyu Jiangtao yang shoudao huang IEEE College of Electrical and Information Engineering Hunan UniversityChangsha410082China CES

Permanent magnet homopolar inductor machine(PMHIM) has attracted much attention in the field of flywheel energy storage system(FESS) due to its merits of simple structure,brushless excitation, and rotor flywheel integration. However, the air-gap flux generated by the PM cannot be adjusted, which would cause large electromagnetic losses in the standby operation state of FESS. To solve this problem, a novel mechanically adjusted variable flux permanent magnet homopolar inductor machine with rotating magnetic poles(RMP-PMHIM) is proposed in this paper. The permanent magnet poles are rotated by an auxiliary rotating device and the purpose of changing the air-gap flux is achieved. First, the structure and operation principle of the proposed RMP-PMHIM are explained. Second,the flux weakening principle of the RMP-PMHIM is analyzed and the equivalent magnetic circuit models under different flux weakening states are built. Third, the parameters of the PM and its fixed structure are optimized to obtain the good electromagnetic performance. Fourth, the electromagnetic performance, including the air-gap flux density, back-EMF, flux weakening ability, loss, etc. of the proposed RMP-PMHIM are investigated and compared. Compared with the non-rotating state of the PM of RPM-PMHIM, the air-gap flux density amplitude can be weakened by 99.95% when the PM rotation angle is 90 degrees, and the no-load core loss can be suppressed by 99.98%,which shows that the proposed RPM-PMHIM is a good candidate for the application of FESS.

关键词： Homopolar inductor machine(HIM) Variable flux Flywheel energy storage system(FESS)

Sliding Mode Fault-tolerant Control Based on Fast Convergence Law for Faults of PMSM

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Chinese Journal of Electrical Engineering 2024年第3期10卷 147-157页

作者： Wan Feng Mengdi Li Wenjuan Zhang shoudao huang Haixia Zhang College of Electronic Information and Electrical Engineering Changsha UniversityChangsha 410000China College of Electrical and Information Engineering Hunan UniversityChangsha 410000China

It is difficult for the traditional PI controller to meet high-performance control requirements under the demagnetization fault of a permanent magnet synchronous motor(PMSM).To address this problem,this study proposes a novel sliding mode fault-tolerant control method for PMSM demagnetization ***,the mathematical model of PMSM under demagnetization fault state is established,and the reasons for poor fault tolerance of the conventional PI controller are analyzed.A new convergence law is used to design the speed loop sliding mode feedback controller,and its stability is ***,an adaptive forgetting factor recursive least squares(AFRLS)flux linkage observer is designed to keep the controller parameter values in line with the actual motor parameter values,to reduce the impact of demagnetization faults on motor control performance and achieve fault-tolerant control of demagnetization ***,simulation and experimental comparison with conventional PI control demonstrate that the proposed method is more robust and resistant to interference.

关键词： Permanent magnet synchronous motor demagnetization faults sliding mode fault-tolerant control flux linkage observer

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经胎电场耦合式电力传输系统的研究

汽车工程 2019年第10期41卷 1145-1151页

作者：陈新黄守道湖南大学电气信息学院长沙410082 湖南人文科技学院能源与机电工程学院娄底417000

针对电动汽车磁电式动态无线电力传输系统电磁辐射严重和成本高等问题,本文中利用轮胎内置钢带与地面铜箔之间的板间电容,建立了经胎电场耦合式电力传输(ECPT)系统,实现车辆行驶过程中的动态无线电力传输。首先分析了轮胎与地面铜箔之... 详细信息

针对电动汽车磁电式动态无线电力传输系统电磁辐射严重和成本高等问题,本文中利用轮胎内置钢带与地面铜箔之间的板间电容,建立了经胎电场耦合式电力传输(ECPT)系统,实现车辆行驶过程中的动态无线电力传输。首先分析了轮胎与地面铜箔之间的板间电容情况,接着根据电容耦合双谐振拓扑结构二端口网络的阻抗匹配情况分析了板间电容和工作频率等对ECPT系统负载功率和传输效率的影响,并给出了ECPT系统的电路拓扑设计和参数优化方法。最后通过仿真和实验,验证了ECPT系统的实际效果,实现了60W的无线电力传输。

关键词：电场耦合无线电力传输轮胎钢带电容耦合阻抗匹配

Analysis of Magnetic Field and Torque for All-Harmonic-Torque Motor with Surface-Mounted Permanent Magnets

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CES Transactions on Electrical Machines and Systems 2018年第1期2卷 175-180页

作者： Wenjuan Zhang Jian Gao Litao Dai shoudao huang Department of Electronic Information and Electrical Engineering Changsha UniversityChangsha410002 China College of Electrical and Information Engineering Hunan UniversityChangsha410082 China

With the development of the advanced industrial products and technologies,the requirements for permanent magnet synchronous motors(PMSM)with high torque density are *** paper proposed a new type of PMSM,named All-Harmonic-Torque PMSM(AHT-PMSM),which could use all harmonics of the magneto motive force(MMF)generated by permanent magnets and armature currents to enhance the electromagnetic *** stator windings structure,drive converter configurations and control model of the AHT-PMSM are illustrated *** then the harmonic characteristics of the MMF generated by permanent magnets and armature currents are *** is found that the MMFs of permanent magnets and armature currents include the same order harmonics and each order harmonic is orthonormal for each *** the calculation process of the average electromagnetic torque for AHT-PMSM based on harmonic MMFs is *** is demonstrated that the theoretical average electromagnetic torque of AHT-PMSM is improved by 23%comparing to that of the normal sinusoidal PMSM when they are with the same structure sizes and armature MMFs.A 24-slot/4-pole AHT-PMSM and sinusoidal PMSM prototypes with the same sizes are modeled and manufactured,the comparison conclusion is validated by the finite element analyses(FEA)and experimental results.

关键词： AHT-PMSM electromagnetic torque harmonics magneto motive force(MMF)