摘要
受逆变器弱馈特性和电流相位受控特性影响,光伏场站送出线路的光伏侧距离保护抗过渡电阻能力弱。该文分析了采用抑制负序电流控制策略的光伏场站送出线路在不对称短路故障下的复合序网,提出针对光伏场站送出线路不对称短路故障的自适应距离保护原理。利用负序网络中光伏侧开路的性质,通过本地测量值实时计算对侧系统等效阻抗和故障点电流,将其代入阻抗解析模型判断区内外故障。该保护方案使用单端电气量准确计算故障距离,解决了弱馈场景下距离保护抗过渡电阻能力弱的问题。此外,保护能够自适应电网运行方式的改变,不受逆变电源弱馈特性影响,并且可以适用于不同地区对故障期间光伏场站无功支撑的要求。测试结果表明该保护方案可以准确识别区内外不对称故障。
Due to the influence of inverter weak feed characteristics and current phase controlled characteristics, the anti-transition resistance ability of distance protection on photovoltaic side of transmission line of Photovoltaic Station is weak. This paper analyzed the composite sequence network of the transmission line of photovoltaic station under asymmetric short circuit fault by using the control strategy of restraining negative sequence current, and proposed the adaptive distance protection principle for the asymmetric short circuit fault of transmission line of photovoltaic station. Based on the open circuit property of photovoltaic side in negative sequence network, the equivalent impedance and fault point current of opposite side system were calculated in real time by local measured values, which were substituted into impedance analytical model to judge the faults inside and outside the area.The fault distance was accurately calculated by using single terminal electric quantity, which solves the problem of weak resistance to transition resistance of distance protection in weak feed scenario. In addition, the protection can adapt to the change of grid operation mode, and was not affected by the weak feed characteristics of inverter, and can be applied to the requirements of reactive power support of photovoltaic stations in different regions during fault. The test results show that the protection scheme can accurately identify the asymmetric faults inside and outside the protection zone.
作者
晁晨栩
郑晓冬
高飘
邰能灵
金甚达
涂崎
孙天甲
李卫彬
安怡然
CHAO Chenxu;ZHENG Xiaodong;GAO Piao;TAI Nengling;JIN Shenda;TU Qi;SUN Tianjia;LI Weibin;AN Yiran(Key Laboratory of Control of Power Transmission and Conversion(Shanghai Jiao Tong University),Ministry of Education,Minhang District,Shanghai 200240,China;State Grid Shanghai Electric Power Company,Pudong New District,Shanghai 200122,China)
出处
《中国电机工程学报》
EI
CSCD
北大核心
2022年第18期6681-6692,共12页
Proceedings of the CSEE
基金
国家自然科学基金项目(51877135)
上海市启明星计划(18QA1402100)
国网上海市电力公司配网分布式光伏网源协调性研究(SGSH0000DKJS2000211)。
关键词
光伏场站送出线路
附加阻抗
距离保护
抗过渡电阻
抑制负序电流控制策略
photovoltaic station transmission line
additional impedance
distance protection
impedance transition resistance
negative sequence current suppression control strategy
