摘  要：針對傳統功率因數測量方法存在的問題，基于廣義諧波小波的優良特性，結合功率因數定義，提出測量工頻功率因數的廣義諧波小波算法。該算法通過對采樣離散化后的電壓與電流信號進行工頻提取，然后對其進行重構，最終結合功率因數定義來實現。建立算法的數學模型，對其進行仿真分析，最后通過液壓系統實驗對算法進行驗證，提取出完全基于工頻的功率因數。分析結果表明：與其他算法特別是與正交小波相比，基于廣義諧波小波的工頻功率因數測量算法速度快、精度高，測量誤差＜3.5%，具有較好的工程實用價值。
關鍵詞：廣義諧波小波；功率因數；快速傅里葉變換；Mallat算法
文獻標志碼：A       文章編號：1674-5124（2016）01-0016-05
Measuring algorithm for power frequency factor based on
general harmonic wavelet
ZHANG Yuan1，2， WANG Nan3
（1. School of Electronic Information and Electric Engineering，Shanghai Jiao Tong University，
Shanghai 200240，China；
2. Engineering Department of 705 Research Institute，CSIC，Shanghai 200245，China；
3. School of Mechanical Engineering，Shanxi University of Technology，Hanzhong 723001，China）
Abstract: To solve the existing problems of traditional power factor measuring methods, general harmonic wavelet is proposed to measure the power factors based on the features of the general harmonic wavelet, i.e., zero phase-shift, the sampling frequency and points of data series that remain unchanged at different decomposition scales, as well as the definition of power factors. The operating procedure of the algorithm is as follows: First, the discretized voltage and current signals are extracted in power frequency; Second, the results obtained are reconstructed; third, it is measured with the definition of power factors. Besides, a mathematical model is established for simulation analysis. Then, the algorithm is verified through hydraulic system tests and the power frequency factor is obtained. The analyzing results have shown that the algorithm is fast and precise less than 3.5% in terms of measuring errors compared with other algorithms (especially orthogonal wavelet), it can be applied in some engineering fields.
Keywords: general harmonic wavelet； power factor； FFT； Mallat algorithm