摘要
可控移相器(thyristor controlled phase shifting transformer,TCPST)接入可有效改善电网潮流分布,也可能对系统短路电流产生影响。目前广东电网部分500 kV变电站短路电流临近限值,故尝试在故障时采用TCPST抑制系统短路电流。首先根据TCPST结构和原理建立其三序数学模型,分析交流系统故障下TCPST影响短路电流的因素;然后提出TCPST故障限流控制策略,当电网发生短路故障时,故障限流控制策略使TCPST等效为高阻抗串联在回路中,将系统流经TCPST的电流限制在较低数值,从而抑制故障点的短路电流;最后以广东电网为例,应用PSCAD/EMTDC软件进行算例仿真,结果表明TCPST在一定范围内对短路电流的抑制效果明显,能有效提高系统资源优化配置能力。
The controllable phase shifting transformer(TCPST)can effectively improve the power flow distribution of the power grid and increase the transmission capacity of the line,but it may also affect the short-circuit current of the system.At present,part of the short-circuit current of the 500 kV grid in Guangdong power grid is close to the limited value,thus it attempts to use the TCPST to suppress the short-circuit current of the system.Firstly,the three-sequence mathematical model of the TCPST is established according to its structure and principle,so as to analyze the factors affecting the short-circuit current of the TCPST in case of AC system failure.Then the fault current limiting control strategy for the TCPST is proposed.When a short-circuit fault occurs in the power grid,this strategy can make the TCPST equivalent to a high-impedance series connected in the loop and limit the system current flowing through the TCPST to a lower value,thereby suppressing the short-circuit current at the fault point.Finally,taking Guangdong power grid as an example,this paper uses the transient software PSCAD/EMTDC to simulate and verify the control strategy.The results show that it can effectively suppress system short-circuit current within a certain range and improve the capacity of the system optimizing and allocating the resources.
作者
余珊
夏成军
范国晨
李作红
李峰
余梦泽
刘若平
YU Shan;XIA Chengjun;FAN Guochen;LI Zuohong;LI Feng;YU Mengze;LIU Ruoping(School of Electric Power Engineering,South China University of Technology,Guangzhou,Guangdong 510641,China;Grid Planning&Research Center of Guangdong Power Grid Co.,Ltd.,Guangzhou,Guangdong 510080,China;Guangdong Provincal Key Laboratory of Intelligent Operation and Control for New Energy Power System,Guangzhou,Guangdong 510663,China)
出处
《广东电力》
2022年第6期41-49,共9页
Guangdong Electric Power
基金
广东省重点领域研发计划项目(2019B111109001)
中国南方电网有限责任公司科技项目(GDKJXM20198313)。
关键词
可控移相器
短路电流
等效数学模型
潮流控制
限流控制
thyristor controlled phase shifting transformer
asymmetric short-circuit current
equivalent mathematical model
flow control
current limit control
