摘要
为解决光伏并网系统并网阀侧保护因换流器弱馈特性而拒动的问题,提出了基于主动探测式的保护新原理。故障后以新能源系统的故障限流策略代替闭锁策略,避免因电网扰动而引起的新能源系统快速闭锁,利用附加注入控制策略向换流器交流网侧注入特征频率的探测信号以增加故障信息,通过基于改进的距离保护判据结合反时限延时动作特性与网侧的保护形成配合关系,从而实现故障的选择性切除。仿真验证了区内外不同故障类型和故障位置下保护原理的判别情况,证明了原理的有效性。注入特征频率的探测信号解决了传统距离保护受对端助增电流的影响,实现了基于单端量的准确测距,结合反时限延时动作策略后可以全范围整定。
To solve the problem that the valve side protection of photovoltaic grid-connected system refuses to operate due to the weak feed characteristics of grid-connected converter,a new protection principle based on active detection method is proposed.When the fault occurs,the fault current limiting strategy of the new energy system is used to replace the blocking strategy,so as to avoid the rapid blocking of the new energy system caused by the grid disturbance.Then,the detection signal of the characteristic frequency is injected into the AC grid side of the converter by the additional injection control strategy,and the fault information is increased.Based on the improved distance protection criterion,the coordinated relationship between the anti-time delay action characteristics and the protection of the grid side is formed to realize the selective removal of the fault.The simulation verifies the discrimination of protection principle under different fault types and fault locations inside and outside the area,and proves the effectiveness of the principle.The fault information added by the detection signal of the injected characteristic frequency solves the problem that the traditional distance protection is affected by the end injection.The accurate ranging based on single-terminal quantity is realized,and the full range setting can be achieved after combining the anti-time delay action strategy.
作者
汤耀景
孔凡坊
宋国兵
张彩友
陈水耀
裘愉涛
常仲学
陈福锋
TANG Yaojing;KONG Fanfang;SONG Guobing;ZHANG Caiyou;CHEN Shuiyao;QIU Yutao;CHANG Zhongxue;CHEN Fufeng(State Grid Wenzhou Power Supply Company of Zhejiang Electric Power Co.,Ltd.,Wenzhou 325700,China;School of Electrical Engineering,Xi’an Jiaotong University,Xi’an 710049,China;Zhejiang Electric Power Co.,Ltd.,Hangzhou 310016,China;Guodian Nanjing Automation Co.,Ltd.,Nanjing 210003,China;School of Electrical Engineering,Southeast University,Nanjing 210096,China)
出处
《供用电》
2023年第1期41-48,共8页
Distribution & Utilization
基金
国家电网有限公司总部科技项目(52094020006U)
国网浙江省电力有限公司科技项目(5211WZ2000X4)。
关键词
光伏并网系统
继电保护
主动探测
距离保护
故障识别
photovoltaic grid-connected system
relay protection
active detection method
distance protection
fault identification
