Fast Measurement Method of Voltage Unbalance Factor Based on Windowed FFT
Wen He1, Jin Ran1, Meng Juan2, Li Fuhai1
1. College of Electrical and Information Engineering Hunan University Changsha 410082 China; 2. Department of Mechanical and Electrical Engineering Beijing Vocational College of Labor and Social Security Beijing 100029 China
Abstract:The voltage unbalance factor (VUF) is one of the most important parameters of power quality. The measurement of VUF depends on both the precise estimation of voltage phasors and the fast calculation of the magnitude of the zero, positive, and negative sequences. However, the accuracy of voltage phasors estimation is affected by the spectrum leakage and picket fence effect, and the measurement speed of VUF is limited because of the square root operation in the calculation of phase sequences. In this paper, a fast measurement method of voltage unbalance factor based on windowed interpolation fast Fourier transform (FFT) was presented. Firstly, windowed interpolation FFT was applied to calculate the voltage phasors. Then, the square root operation in the calculation of phase sequences was transformed into polynomial operation based on the geometric partitions. The simulation results show that the proposed method could achieve the same level of accuracy with the method recommended by GB/T 15543—2008. The measured results from the experiments of VUF verify the effective and practicability of the proposed method in further.
温和, 金冉, 蒙娟, 黎福海. 电压不平衡度的加窗FFT快速测量方法[J]. 电工技术学报, 2017, 32(16): 275-283.
Wen He, Jin Ran, Meng Juan, Li Fuhai. Fast Measurement Method of Voltage Unbalance Factor Based on Windowed FFT. Transactions of China Electrotechnical Society, 2017, 32(16): 275-283.
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