基于时间尺度变换策略的幅频测量用自适应陷波器算法

A Time Scale Transformation Based Adaptive Notch Filter Algorithm for Measurement of Amplitude and Frequency of Power Signals

现有电力信号幅频测量算法在动态条件下的测量精度和响应时间方面还有待改善,为此提出了基于时间尺度变换的自适应陷波器(adaptive notch filter,ANF)算法进行幅频测量。该算法对时间进行尺度变换,得到新时间尺度下的ANF动态方程,能够消除频率参数和滤波器之间的非线性耦合,将状态估计方程等价为线性时不变系统,并进行离散化处理。该算法能够有效消除谐波和噪声干扰,快速准确地测量动态变化的幅值和频率。算例结果验证了该方法的有效性,可满足在线测量的要求。

The measurement accuracy and response time of existing amplitude and frequency measurement algorithms for electric power signals are to be improved, so an adaptive notch filter （ANF） algorithm based on time scale transformation is proposed to measure the frequencies and amplitudes. The proposed algorithm performs time scale transformation and a dynamic ANF equation under new time scale is obtained. The obtained dynamic ANF equation can eliminate nonlinear coupling between frequency parameter and filter, and can make the state estimation equation equivalent to a linear time-invariant system and carry out discretization process. The proposed algorithm can effectively eliminate the interferences from noise and harmonics and measure dynamically varying amplitudes and frequencies of power signals rapidly and accurately. Results of case study show that the proposed method is effective and can meet the demand of on-line measurement.