With the rapid development of renewable energy,wind-thermal-bundled power transmission by line-commutated converter based high-voltage direct current(LCC-HVDC)systems has been widely developed.The dynamic interaction ...With the rapid development of renewable energy,wind-thermal-bundled power transmission by line-commutated converter based high-voltage direct current(LCC-HVDC)systems has been widely developed.The dynamic interaction mechanisms among permanent magnet synchronous generators(PMSGs),synchronous generators(SGs),and LCC-HVDC system become complex.To deal with this issue,a path analysis method(PAM)is proposed to study the dynamic interaction mechanism,and the damping reconstruction is used to analyze the damping characteristic of the system.First,based on the modular modeling,linearized models for the PMSG subsystem,the LCC-HVDC subsystem,and the SG subsystem are established.Second,based on the closed-loop transfer function diagram of the system,the disturbance transfer path and coupling relationship among subsystems are analyzed by the PAM,and the damping characteristic analysis of the SG-dominated oscillation mode is studied based on the damping reconstruction.Compared with the PAM,the small-signal model of the system is obtained and eigenvalue analysis results are presented.Then,the effect of the control parameters on the damping characteristic is analyzed and the conclusions are verified by time-domain simulations.Finally,the penalty functions of the oscillation modes and decay modes are taken as the objective function,and an optimization strategy based on the Monte Carlo method is proposed to solve the parameter optimization problem.Numerical simulation results are presented to validate the effectiveness of the proposed strategy.展开更多
远距离海上风电越来越多地选择柔性直流经海缆送出的方式。采用电缆的柔性直流(voltage source converter based high voltage direct current,VSC-HVDC)输电系统,其故障特性比传统架空线直流输电系统更加复杂。文中基于对称单极拓扑的...远距离海上风电越来越多地选择柔性直流经海缆送出的方式。采用电缆的柔性直流(voltage source converter based high voltage direct current,VSC-HVDC)输电系统,其故障特性比传统架空线直流输电系统更加复杂。文中基于对称单极拓扑的双端VSC-HVDC海上风电送出工程,简化了电缆和VSC-HVDC输电系统的数学模型,分析换流变阀侧交流系统单相接地和直流电缆线路单极接地等典型故障下的故障特性,运用叠加原理对故障机理进行解释;根据不同故障类型的故障源等效出不同的故障回路,得到了长距离电缆显著的电容效应对VSC-HVDC系统故障特征的复杂影响;利用实时数字仿真平台,搭建远海风电送出系统硬件在环仿真模型,验证了故障机理解析分析的正确性。展开更多
对输配电系统中的高压直流(High Voltage Direct Current,HVDC)进行检测可以提高电网中高压直流的运行效率。为了提高电网输配电高压直流检测性能,提出了基于混沌特征分析的电网输配电高压直流检测技术研究。通过高压直流信号的小波分解...对输配电系统中的高压直流(High Voltage Direct Current,HVDC)进行检测可以提高电网中高压直流的运行效率。为了提高电网输配电高压直流检测性能,提出了基于混沌特征分析的电网输配电高压直流检测技术研究。通过高压直流信号的小波分解,获得小波重构系数,引入信息熵理论,计算出高压直流信号在不同尺度下的小波包时间熵,提取出输配电系统中的高压直流特征量。在引入混沌特征分析理论的基础上,构建输配电高压直流特征点的偏差函数,通过求解偏差函数的最小值,检测出输配电系统中的高压直流信号。实验结果表明,所提技术将高压直流检测的时间控制在2 s以内,大大提高了电网输配电的高压直流检测效率。展开更多
基金supported in part by the National Natural Science Foundation of China(No.U22B20109).
文摘With the rapid development of renewable energy,wind-thermal-bundled power transmission by line-commutated converter based high-voltage direct current(LCC-HVDC)systems has been widely developed.The dynamic interaction mechanisms among permanent magnet synchronous generators(PMSGs),synchronous generators(SGs),and LCC-HVDC system become complex.To deal with this issue,a path analysis method(PAM)is proposed to study the dynamic interaction mechanism,and the damping reconstruction is used to analyze the damping characteristic of the system.First,based on the modular modeling,linearized models for the PMSG subsystem,the LCC-HVDC subsystem,and the SG subsystem are established.Second,based on the closed-loop transfer function diagram of the system,the disturbance transfer path and coupling relationship among subsystems are analyzed by the PAM,and the damping characteristic analysis of the SG-dominated oscillation mode is studied based on the damping reconstruction.Compared with the PAM,the small-signal model of the system is obtained and eigenvalue analysis results are presented.Then,the effect of the control parameters on the damping characteristic is analyzed and the conclusions are verified by time-domain simulations.Finally,the penalty functions of the oscillation modes and decay modes are taken as the objective function,and an optimization strategy based on the Monte Carlo method is proposed to solve the parameter optimization problem.Numerical simulation results are presented to validate the effectiveness of the proposed strategy.
文摘远距离海上风电越来越多地选择柔性直流经海缆送出的方式。采用电缆的柔性直流(voltage source converter based high voltage direct current,VSC-HVDC)输电系统,其故障特性比传统架空线直流输电系统更加复杂。文中基于对称单极拓扑的双端VSC-HVDC海上风电送出工程,简化了电缆和VSC-HVDC输电系统的数学模型,分析换流变阀侧交流系统单相接地和直流电缆线路单极接地等典型故障下的故障特性,运用叠加原理对故障机理进行解释;根据不同故障类型的故障源等效出不同的故障回路,得到了长距离电缆显著的电容效应对VSC-HVDC系统故障特征的复杂影响;利用实时数字仿真平台,搭建远海风电送出系统硬件在环仿真模型,验证了故障机理解析分析的正确性。
文摘对输配电系统中的高压直流(High Voltage Direct Current,HVDC)进行检测可以提高电网中高压直流的运行效率。为了提高电网输配电高压直流检测性能,提出了基于混沌特征分析的电网输配电高压直流检测技术研究。通过高压直流信号的小波分解,获得小波重构系数,引入信息熵理论,计算出高压直流信号在不同尺度下的小波包时间熵,提取出输配电系统中的高压直流特征量。在引入混沌特征分析理论的基础上,构建输配电高压直流特征点的偏差函数,通过求解偏差函数的最小值,检测出输配电系统中的高压直流信号。实验结果表明,所提技术将高压直流检测的时间控制在2 s以内,大大提高了电网输配电的高压直流检测效率。
