Simplified and fast method without considering filter for voltage flicker detection

Abstract

Voltage fluctuations caused output variation in the distributed energy system (such as solar, photovoltaic, and wind) produce flickers. The extraction of voltage flicker envelope parameters and accurate calculation of voltage flicker values are important for voltage flicker detection. Traditional digital filters need to be calculated according to the sampling frequency before they can be designed so that the flicker meter can only sample at a fixed frequency. To overcome the shortcomings of digital filters, a new method for measuring flickers is presented in this study. The proposed method uses analytical mode decomposition (AMD) based on spectral correction and a novel constructed mutual convolution window. The voltage flicker envelope can be extracted using an AMD method, which can replace the filter used in traditional methods, it can be analysed to obtain the corrected spectrum, which is based on an improved fast Fourier transform. The proposed method simplifies the voltage flicker detection process and exhibits high detection accuracy, which with lower detection relative error and stronger anti-interference ability. The simulation analysis and experimental results show that this approach can effectively overcome problems associated with voltage flicker measurements, such as single modulation wave frequency change and multi-frequency modulation wave fluctuation.