HCM3000中预测性熄弧角控制算法的实现

Design of predictive extinction angle control algorithm used in HCM3000

HCM3000是特高压直流输电控制保护平台。平台采用实测性熄弧角策略来防止换向失败,该策略原理是检测到换相失败后增大点火角防止后续换向失败,因此它只能避免连续换向失败,但不能减少换向失败,所以在HCM3000中需引入预测型熄弧角控制算法。该算法通过实时采样计算来预测换向失败,在失败之前提前触发点火角避免换向失败。HCM3000中实现该算法主要有两个制约因素,一是采样及计算的快速性和实时性,二是预测型算法和HCM3000点火系统的适配。为了满足实时性和快速性,整个算法在FPGA内实现,为了适配HCM3000的点火系统,将点火时间转化为点火角度。HCM3000引入该算法后,通过RTDS仿真平台,模拟了单相及三相交流故障、丢脉冲等典型的会产生换相失败的故障。试验表明引入该算法后,HCM3000显著地降低了换向失败的概率。

HCM3000 is a control protection platform for UHVDC transmission. It uses a measured extinction angle algorithm for avoiding commutation failure. The theory is that adding ignition angle when detects the commutation failure for avoiding the following commutation failure, so it just can avoid continuous commutation failure, but cannot decrease the probability of commutation failure. Therefore, the HCM3000 adopts the predictive extinction angle control algorithm which can trigger ignition angle before commutation failure for avoiding commutation failure. In the HCM3000, there are two main constraints during the implementation, one is the rapidity and real-time performance of sampling and the computation, the other is the adaptation between predictive algorithm and HCM3000 ignition system. To meet the above two constraints, the whole algorithm is realized in FPGA and the ignition time is converted to ignition angle, respectively. After introducing the algorithm into HCM3000, this paper simulates typical faults which can lead to commutation failure, such as single-phase and three-phase AC fault, pulse loss through RTDS simulation platform. Test results show that HCM3000 significantly reduce the probability of commutation failure after adopting the algorithm.