Abstract:This paper proposes a novel hybrid wavelet-energy operator method for accurate voltage sag detection and measurement. In the proposed method, the voltage sag is decomposed into two signal parts by wavelet transform: one is a detail signal, the other is an approximation signal. And in the detail signal, the start time and the end time of the sag signal can be detected. By applying an energy operator to the approximation signal, the temporary sag decline in value can be measured accurately and quickly. At the same time, the wavelet transform (WT) in this method acts like a filter. WT can weaken or remove the high frequency disturbance from voltage sag to enhance the noise immunity and accuracy of the energy operator. Simulation and experimental results verify the effectiveness of the algorithm.
鲁波涌, 黄文清. 结合小波变换和能量算子的电压暂降检测方法[J]. 电工技术学报, 2011, 26(5): 171-177.
Lu Boyong, Huang wenqing. Hybrid Wavelet-Energy Operator Method for Voltage Sag Detection. Transactions of China Electrotechnical Society, 2011, 26(5): 171-177.
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