Voltage Flicker Detection Based on Chirp-z Transform

Studying of the IEC flicker meter shows that the instantaneous flicker sensation level S can be calculated directly if the spectrums of fluctuating component of voltage are known. In this paper a novel flicker measurement method is proposed. First, the square demodulation is used to obtain the fluctuating component of voltage, and then the chirp-z transform (CZT) is used to get the amplitude and the frequency of wave component, and final the instantaneous flicker sensation level S. To process the wave component by CZT can acgwire precise spectrums without prolonging the sampling time and decrease the error produced by spectrum leakage. The IEC flicker meter and new method is compared in simulation and test. The result verified the correctness and efficiency of the theoretical prediction.