摘要
电力电子设备渗透率的不断提高使得电力系统转动惯量和阻尼水平下降,对新型电力系统安全稳定运行带来不可忽略的影响。目前并网变换器系统判稳方法常采用奈奎斯特判据和广义奈奎斯特判据,但这两种判据均适用于阻抗比中不含右半平面(right half plane, RHP)极点的场景。针对上述问题,基于考虑正负序耦合和源荷之间耦合的等效单输入单输出(single-input single-output, SISO)系统阻抗模型,提出了考虑RHP极点的三相变换器并网系统判稳方法。首先,对研究系统的RHP极点个数及奈奎斯特曲线包围点(-1, j0)的次数进行估算。然后,在奈奎斯特判据的基础上,利用SISO系统阻抗伯德图进行分析,在系统存在RHP极点的情况下对系统的稳定性进行判断。最后,基于Matlab/Simulink中搭建电磁暂态仿真模型,验证了在有无RHP极点的不同场景下,所提判稳方法均能对三相变换器并网系统的小干扰稳定性进行有效分析。
With the continuous increasing proportion of the converters,the moment of inertia and damping of power systems are reduced,which has a non-negligible impact on the safe and stable operation of the new power system.At present,the Nyquist criterion and the generalized Nyquist criterion are often used to judge the stability of the grid-connected converter system.However,both are based on the premise that no right-half-plane(RHP)pole exists in the impedance ratio.To solve this problem,on the basis of establishing single-input single-output(SISO)impedance model considering coupling between positive and negative sequence,as well as coupling between source and load,a stability analysis method considering the RHP pole is proposed.First,the number of RHP poles and the number of Nyquist curve bounding points(-1,j0)of the research system are estimated.Secondly,combining with the Nyquist criterion,the stability of systems with RHP poles can be accurately judged by using an impedance Bode diagram of the SISO system.Finally,based on the electromagnetic transient simulation model built in Matlab/Simulink,it is verified that the proposed method can effectively analyze the small-signal stability of the system with or without RHP poles.
作者
邢法财
蒋哲
武诚
张志轩
田鸣鹤
赵玉静
叶华
XING Facai;JIANG Zhe;WU Cheng;ZHANG Zhixuan;TIAN Minghe;ZHAO Yujing;YE Hua(State Grid Shandong Electric Power Research Institute,Jinan 250000,China;Shandong Smart Grid Technology Innovation Center,Jinan 250000,China;State Grid Shandong Electric Power Dispatching and Control Center,Jinan 250000,China;School of Electrical Engineering,Shandong University,Jinan 250061,China)
出处
《电力系统保护与控制》
EI
CSCD
北大核心
2024年第6期42-50,共9页
Power System Protection and Control
基金
国家电网公司科技项目资助(520626220011)。
关键词
并网变换器
单输入单输出
小干扰稳定性
右半平面极点
源荷耦合
阻抗伯德图
grid-connected converter
single-input single-output
small-signal stability
right-half-plane pole
coupling between source and load
impedance Bode diagram
