考虑锁相暂态响应的光伏发电系统三相短路电流计算方法  

Three⁃phase short⁃circuit current calculation method of photovoltaic power generation system considering phase⁃locked loop transient response

作　　者：许守东 毕书奇 李世伟 欧阳金鑫[2] 石恒初 张丽 奚鑫泽 XU Shoudong;BI Shuqi;LI Shiwei;OUYANG Jinxin;SHI Hengchu;ZHANG Li;XI Xinze(Electric Power Research Institute of Yunnan Power Grid Co.,Ltd.,Kunming 650217,China;State Key Laboratory of Power Transmission Equipment Technology(Chongqing University),Chongqing 400044,China;Yunnan Power Grid Co.,Honghe Power Supply Bureau,Mengzi 661100,China;Yunnan Electric Power Dispatching Control Center,Kunming 650000,China)

机构地区：[1]云南电网有限责任公司电力科学研究院,云南昆明650217 [2]输变电装备技术全国重点实验室(重庆大学),重庆400044 [3]云南电网有限责任公司红河供电局,云南蒙自661100 [4]云南电力调度控制中心,云南昆明650000

出　　处：《电工电能新技术》2024年第7期32-40,共9页Advanced Technology of Electrical Engineering and Energy

基　　金：国家自然科学基金项目(51877018);云南电网公司科技项目(YNKJXM20220177)。

摘　　要：光伏发电系统具有不同于同步机的故障响应特性,给电力系统故障保护与控制带来严峻挑战。锁相环的输出直接影响光伏发电系统的故障响应特性,特别是在电网故障后电压相位跳变使得锁相环输出呈现非周期性的暂态响应偏差,对光伏输出短路电流产生较大影响。现有研究忽略锁相暂态过程,可能造成光伏及其并网系统短路电流的分析计算出现较大误差。为此,本文推导了光伏锁相环输出相位与并网点电压相位间偏差的解析表达式,分析了锁相偏差的时域变化特性及其影响因素和锁相偏差对光伏发电系统三相短路电流的影响,从而提出了考虑锁相暂态响应的光伏发电系统三相短路电流解析计算方法,并分析了短路电流的特征,最后搭建光伏并网系统仿真模型,验证了理论分析的正确性。Photovoltaic power generation system has different fault response characteristics from synchronous ma⁃chine,which brings severe challenges to power grid fault protection and control.The output of the phase⁃locked loop of the photovoltaic power generation system directly affects the fault response characteristics of the photovoltaic system,especially the non⁃periodic transient response deviation of the output of the phase⁃locked loop caused by the voltage phase jump after the grid fault,which has a great impact on the short⁃circuit current.The existing studies ignore the phase⁃locked transient process or assume that the phase⁃locked deviation is constant,which may cause large errors in the analytical calculation of photovoltaic short⁃circuit current.For this reason,in the present paper the expression of the deviation between the output phase of the photovoltaic phase⁃locked loop and the voltage phase of the grid⁃connected point is derived,the time⁃domain variation characteristics of the phase⁃locked deviation and its influencing factors are analyzed,and the influence of the phase⁃locked deviation on the three⁃phase short⁃circuit current of the photovoltaic power generation system is analyzed,thus the analytical calculation method of the three⁃phase short⁃circuit current of the photovoltaic power generation system considering the transient response of the phase⁃locked loop is proposed,and the characteristics of the short⁃circuit current are analyzed,Finally,the simula⁃tion model of photovoltaic grid⁃connected system is built to verify the correctness of the theoretical analysis.

关 键 词：光伏发电 短路电流 三相短路 锁相环 故障分析 

分 类 号：TM713[电气工程—电力系统及自动化]