The impacts of large-scale grid-connected wind farm on direct-driven permanent magnet synchronous generator(PMSG)type are discussed on the small signal stability performances of power systems.Firstly,a simplified prac...The impacts of large-scale grid-connected wind farm on direct-driven permanent magnet synchronous generator(PMSG)type are discussed on the small signal stability performances of power systems.Firstly,a simplified practical model of wind farm of PMSG type is derived for analyzing small signal stability.The rotor-fluxoriented control strategy is applied to the modelling of PMSG.Secondly,the framework of small signal stability analysis incorporating wind farm of PMSG type is built.Finally,the different simulation scenarios based on the IEEE 3-generator-9-bus test system as benchmark are designed to conduct the eigenvalue analysis and to assess the impacts of wind farm of PMSG type on power system small signal stability.Some conclusions are drawn with simulation results.展开更多
Small signal instability may cause severe accidents for power system if it can not be dear correctly and timely. How to maintain power system stable under small signal disturbance is a big challenge for power system o...Small signal instability may cause severe accidents for power system if it can not be dear correctly and timely. How to maintain power system stable under small signal disturbance is a big challenge for power system operators and dispatchers. Time delay existing in signal transmission process makes the problem more complex. Conventional eigenvalue analysis method neglects time delay influence and can not precisely describe power system dynamic behaviors. In this work, a modified small signal stability model considering time varying delay influence was constructed and a new time delay controller was proposed to stabilize power system under disturbance. By Lyapunov-Krasovskii function, the control law in the form of nonlinear matrix inequality （NLMI） was derived. Considering synthesis method limitation for time delay controller at present, both parameter adjustment method by using linear matrix inequality （LMI） solver and iteration searching method by solving nonlinear minimization problem were suggested to design the controller. Simulation tests were carried out on synchronous-machine infinite-bus power system. Satisfactory test results verify the correctness of the proposed model and the feasibility of the stabilization approach.展开更多
随着新能源在电网中渗透比例越来越高,大量不同控制方式的电力电子变流器接入电网,其中,变流器与电网阻抗交互易引发小扰动失稳现象,威胁新型电力系统安全。针对构网型(Grid-forming,GFM)储能与跟网型(Grid-following,GFL)光伏混联发电...随着新能源在电网中渗透比例越来越高,大量不同控制方式的电力电子变流器接入电网,其中,变流器与电网阻抗交互易引发小扰动失稳现象,威胁新型电力系统安全。针对构网型(Grid-forming,GFM)储能与跟网型(Grid-following,GFL)光伏混联发电系统,建立混联系统单输入单输出(Single input and single output,SISO)等效阻抗模型,基于正网络阻尼判据,分析了变流器控制方式、GFM储能运行方式以及电网强度对混联系统阻尼特性和稳定性的影响规律。研究结果表明在GFL光伏并网系统中接入GFM储能可以有效提升混联系统在弱网条件下的稳定性,但同时会导致其在强电网条件下的稳定性变差。对于光伏并入弱电网的场景,可在距离光伏送端较近的位置配置GFM储能,用以增强系统阻尼性能。最后,通过Matlab/Simulink仿真模型验证了理论分析的正确性。展开更多
基金supported by Research Project of Science and Technology from Shenzhen Government of China(No.JC200903180528A)
文摘The impacts of large-scale grid-connected wind farm on direct-driven permanent magnet synchronous generator(PMSG)type are discussed on the small signal stability performances of power systems.Firstly,a simplified practical model of wind farm of PMSG type is derived for analyzing small signal stability.The rotor-fluxoriented control strategy is applied to the modelling of PMSG.Secondly,the framework of small signal stability analysis incorporating wind farm of PMSG type is built.Finally,the different simulation scenarios based on the IEEE 3-generator-9-bus test system as benchmark are designed to conduct the eigenvalue analysis and to assess the impacts of wind farm of PMSG type on power system small signal stability.Some conclusions are drawn with simulation results.
基金Project(51007042)supported by the National Natural Science Foundation of China
文摘Small signal instability may cause severe accidents for power system if it can not be dear correctly and timely. How to maintain power system stable under small signal disturbance is a big challenge for power system operators and dispatchers. Time delay existing in signal transmission process makes the problem more complex. Conventional eigenvalue analysis method neglects time delay influence and can not precisely describe power system dynamic behaviors. In this work, a modified small signal stability model considering time varying delay influence was constructed and a new time delay controller was proposed to stabilize power system under disturbance. By Lyapunov-Krasovskii function, the control law in the form of nonlinear matrix inequality （NLMI） was derived. Considering synthesis method limitation for time delay controller at present, both parameter adjustment method by using linear matrix inequality （LMI） solver and iteration searching method by solving nonlinear minimization problem were suggested to design the controller. Simulation tests were carried out on synchronous-machine infinite-bus power system. Satisfactory test results verify the correctness of the proposed model and the feasibility of the stabilization approach.
文摘随着新能源在电网中渗透比例越来越高,大量不同控制方式的电力电子变流器接入电网,其中,变流器与电网阻抗交互易引发小扰动失稳现象,威胁新型电力系统安全。针对构网型(Grid-forming,GFM)储能与跟网型(Grid-following,GFL)光伏混联发电系统,建立混联系统单输入单输出(Single input and single output,SISO)等效阻抗模型,基于正网络阻尼判据,分析了变流器控制方式、GFM储能运行方式以及电网强度对混联系统阻尼特性和稳定性的影响规律。研究结果表明在GFL光伏并网系统中接入GFM储能可以有效提升混联系统在弱网条件下的稳定性,但同时会导致其在强电网条件下的稳定性变差。对于光伏并入弱电网的场景,可在距离光伏送端较近的位置配置GFM储能,用以增强系统阻尼性能。最后,通过Matlab/Simulink仿真模型验证了理论分析的正确性。
