基于高耦合分裂电抗器限流装置后灭弧断路器的TRV特性

TRV Characteristics of Post-breaker Circuit Breaker Based on High Coupling Split Reactor Current Limiter

为解决500 kV电网发展过程中短路电流过大的问题,提出了一种基于高耦合分裂电抗器的限流装置。该装置可有效限制短路电流并提高断路器的开断容量,但存在并联断路器同时开断不同时灭弧时瞬态恢复电压超标的问题。文中首先分析限流装置的结构和开断过程,并利用EMTP仿真软件计算不同条件下后灭弧断路器的瞬态恢复电压,得出限流装置参数对瞬态恢复电压的影响。然后在500 k V工程实例中搭建限流装置的仿真模型,分别在不同故障类型下验证限流装置的可行性。仿真结果表明,选择合适的电抗值和并联电容值可有效降低瞬态恢复电压幅值和上升率,且能够达到预期的短路电流限制效果。

In order to solve the problem of excessive short-circuit current in the development of 500 k V power grid,acurrent limiting device based on high coupled split reactor is proposed,which can effectively limit short-circuit cur-rent and improve the breaking capacity of circuit breakers.However,there may be a problem that the transient recov-ery voltage of parallel circuit breakers exceeds the standard when non-synchronous breaking occurs.Firstly,thestructure and interruption process of current limiting device are analyzed.According to its components and operationcharacteristics,the transient recovery voltage of circuit breakers operating under different conditions is calculated byEMTP simulation platform,and the influence of current limiting device parameters on the transient recovery voltageis obtained.Then,a simulation model with 500 k V current limiter is built in an engineering example to verify the fea-sibility of the current limiter under different fault types.The simulation results show that the larger the reactor valuein the current limiting device,the higher the transient recovery voltage and the higher the rise rate of the circuitbreaker after non-synchronous interruption.Selecting the appropriate reactor value and shunting capacitor can effec-tively reduce the amplitude and rate of rise of the transient recovery voltage.