摘要
直流微网群提高了单一直流微网的供电效率,但其复杂的拓扑增加了故障检测的难度,同时直流微网群通信数据的丢失或通信故障,降低了保护的可靠性,甚至失效。为提高保护可靠性,解决直流微网群因通信故障导致保护失效的问题,提出一种基于功率梯度考虑通信故障的协同保护策略。通信正常时,由功率梯度差分构成的单元保护快速有选择地切除短路故障;通信故障时,功率梯度差分保护闭锁,本地功率梯度保护启动。2种保护协同动作,在未增加测量装置情况下兼具单元保护和非单元保护优势,相比过电流或电流差动保护,其故障检测速度更快,灵敏度更高,且不受通信故障影响。最后仿真证实了所提策略的有效性。
Compared with single DC microgrid,DC multi-microgrid improves the power supply efficiency,however,its complex topology increases the difficulty of fault detection.At the same time,the communication failure or data loss of DC multi-microgrid reduces the reliability of protection,and even leads to protection failure.In order to solve the problem of protection failure caused by communication faults and improve the protection reliability,a cooperative protection strategy based on power gradient considering communication faults is proposed.When the communication is normal,the remote power gradient differential protection can quickly and selectively remove the short-circuit faults;In case of communication failure,the power gradient differential protection is locked and the local power gradient protection is started.The two kinds of protections act together,which has the advantages of unit protection and non-unit protection without adding measuring devices.Compared with overcurrent or current differential protection,the cooperative protection strategy has faster fault detection speed and higher sensitivity,and is not affected by communication faults.Finally,simulation results show the effectiveness of the proposed strategy.
作者
张伟亮
张辉
支娜
王韩伟
曾成
ZHANG Weiliang;ZHANG Hui;ZHI Na;WANG Hanwei;ZENG Cheng(School of Electrical Engineering,Xi’an University of Technology,Xi’an 710048,China;State Key Laboratory of Safety Control and Simulation of Power System and Power Generation Equipment,Tsinghua University,Beijing 100084,China)
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2022年第11期4590-4599,共10页
High Voltage Engineering
基金
国家自然科学基金(51877175,52077176)
陕西省重点研发计划(2017ZDXM–GY–003)。
关键词
直流微网群
灵敏性
功率梯度保护
电流差动保护
故障检测
DC multi-microgrid
sensitivity
power gradient protection
current differential protection
fault detection
