The invention discloses a method for extracting
power grid voltage flicker envelope parameters. According to the method,
power grid voltage flicker waveforms are sampled at a constant sampling frequency, a
flicker envelope amplitude modulated wave component is obtained through energy calculation of an improved Teager
energy operator, a cosine window is added to conduct
Chirp-Z conversion, the flicker envelope amplitude modulated
wave frequency and a correction factor of an amplitude modulated wave amplitude value are extracted by improving the
Chirp-Z conversion, and the flicker envelope amplitude modulated wave amplitude value is corrected through the correction factor and accurately obtained; through the combination of the improvement on the
energy operator and the improvement on the
Chirp-Z conversion, the
energy operator is improved, the flicker envelope
demodulation calculation process by the energy operator is improved, the
noise resistance is improved; by improving the Chirp-Z conversion, the flicker
frequency analysis range is flexible and adjustable, and
frequency spectrum leakage generated under the condition of
asynchronous sampling and errors caused by a picket fence effect are effectively avoided; the correction factor of the amplitude modulated wave amplitude value reduces the errors caused by the energy operator, and the
power grid voltage flicker envelope parameters can be accurately measured in real time.