基于强跟踪滤波器的电力系统频率测量算法

摘要

频率在电力系统保护与控制、电能质量监测等领域都起到了关键作用。建立了谐波和噪声干扰下的电压信号的复数状态空间描述,提出了基于强跟踪滤波器(Strong Tracking Filter, STF)的电力系统频率测量算法。解决了扩展复数卡尔曼滤波(Extended Complex Kalman filter, ECKF)算法在算法收敛后,系统状态发生突变的情况下需要重置误差协方差阵来重新跟踪这些变化的问题,进一步提高了其动态跟踪速度。通过与鲁棒型扩展复数卡尔曼滤波(Robust Extended Complex Kalman Filter, RECKF)算法的对比仿真表明,STF测频算法在迅速跟踪电压频率、幅值和相位变化的同时又能够保持较低的跟踪误差。%Frequency plays an important role in power system protection and control, power quality monitoring and other fields. The complex state space description of the voltage signal under harmonics and noise is established, then the strong tracking filter (STF) based frequency-measuring algorithm for power system is proposed. It is not necessary to reset the error covariance matrix for STF as it is for extended complex Kalman filter (ECKF) algorithm to track the sudden state mutation of power system after initial convergence, thus significantly improving its tracking speed. Results of comparative simulation studies of the proposed algorithm with robust extended complex kalman filter (RECKF) algorithm show that the STF-based algorithm is able to quickly track the frequency, amplitude and phase changes while maintaining a considerably low tracking error.