为使同步相量测量在动态情况下满足精度要求,设计了一种基于高斯窗解耦调制函数的复带通滤波算法。给出了对应于不同相量上传速率的测量带宽和滤波延迟,使该方法能输出不失真的幅值调制分量、抑制带外干扰并具有快速动态响应速度。获取基波相位后,利用基于权重最小二乘的频率估计方法代替传统的对相位求导测频方法,提高了频率估计的鲁棒性。仿真和实例分析结果表明:稳态时,所提出的方法符合IEEE标准C37.118-2005中的1级性能要求;动态时,该方法在幅值调制、斜线变化频率和阶跃变化情形下均具有较好的相量和频率测量精度。此外,该方法运算量较小,能满足在线应用要求。
In order to make synchronized phasor measurement meet the accuracy requirements under dynamic conditions, a complex bandpass-filtering algorithm was proposed. Its measurement bandwidth and group delay corresponding to various phasor-uploading rates were provided to make the method be able to output amplitude modulated components without distortion, restrain the out-of-band interference and have short dynamic response time. Based on acquired phase angles, the weighted least squares (WLS) was applied, instead of traditional derivation operation, to improve frequency measurement robustness. Simulation and field test results show that the proposed method complies with the level 1 of IEEE Standard C37.118-2005 under steady state, and has high accuracy under dynamic conditions. In addition, the method has small amount of computation and is fast enough for online application.