摘要
不同电压等级同塔多回输电线路故障类型复杂多样,线路间的零序互感会影响零序功率方向元件的动作性能。以不同电压等级同塔四回线路为例,分析了单回线路故障、同一电压等级线路跨线故障、不同电压等级线路跨线故障及不同电压等级线路复故障时零序功率方向元件的动作行为。对于不同电压等级同塔多回输电线路,分析不同电压等级跨线故障后零序功率方向元件的动作行为时,可以将其分解为若干个相同电压等级线路故障分别进行处理。理论分析表明,零序互感对零序功率方向元件的主要影响为,非故障线路处于强磁弱电条件时,零序功率方向元件会发生误动作。在此基础上,利用RTDS仿真软件对一1 000 kV/500 kV同塔四回线路进行了仿真,结果证明了理论分析的正确性。
Fault types occurred in multi-circuit transmission lines with different voltage classes on the same tower are various, and the zero-sequence mutual induction among the lines will affect the behavior and performance of zero-sequence power direction component. Taking four-circuit transmission lines in different voltage classes on the same tower for example, the behaviors of zero-sequence power direction component under following fault conditions, namely the faults occurred in single circuit line, the cross-country fault occurred in the lines in the same voltage class, the cross-country fault occurred in the lines belonging to different voltage classes and the complex fault occurred in the lines belonging to different voltage classes, are analyzed. For multi-circuit transmission lines with different voltage classes on the same tower, to analyze the behaviors of zero-sequence power direction component under cross-country fault occurred in the lines belonging to different voltage classes, the multi-circuit transmission lines in different voltage classes can be divided into several lines belonging to same voltage classes and processes individually. Theoretical analysis shows that the main influence of zero-sequence mutual induction on zero-sequence power direction component is that when faulty lines are in the strong-magnetic and weak-electric condition, malfunction of zero-sequence power direction component occurs. On this basis, by use of RTDS software a certain four-circuit transmission lines respectively belonging to 1 000 kV and 500 kV power grids on the same tower is simulated, and simulation results prove that the results of theoretical analysis are correct.
出处
《电网技术》
EI
CSCD
北大核心
2011年第12期235-242,共8页
Power System Technology
关键词
同塔多回输电线路
零序互感
零序功率方向元件
跨线故障
复故障
multi-cimuit transmission lines on the same tower
zero-sequence mutual induction
zero sequence power directional component
cross-country fault
complex faults