基于虚拟电感的双馈入直流输电系统连续换相失败的抑制方法

A Method Mitigating Continuous Commutation Failure for Double-Infeed HVDC System Based on Virtual Inductor

文章基于传统直流输电的换相机理,引入虚拟电感这一概念,将其与低压限流控制(voltage dependent current order limiter,VDCOL)相结合共同实现抑制多馈入系统发生连续换相失败的作用。首先从理论上分析了该控制方法的作用机理;然后以传统双馈入系统为例,通过仿真试验分析了该控制方法中的相关参数对其抑制作用的影响;最后,通过模拟交流系统发生故障情况下的仿真试验,验证了所提出的控制方法能够在一定程度上起到抑制连续换相失败、优化故障恢复特性的作用。

This paper analyzes commutation failure mechanism and proposes a new method mitigating continuous commutation failure based on virtual inductor, cooperating with voltage dependent current order limiter （VDCOL）. Firstly, mechanism of the new method is theoretically presented. Then, based on CIGRE HVDC benchmark model, a double-infeed HVDC system with a proposed controller is developed in PSCAD/EMTDC. Simulation results show that the proposed control method based on virtual inductor, to some extent, has ability to mitigate continuous commutation failure. Thus, HVDC fault recovery performances are also improved.