Power cable partial discharge signal detection method and device

The invention discloses a power cable partial discharge signal detection method and device. The method comprises the steps of carrying out the wavelet transformation of a collected power cable partialdischarge signal based on a selected wavelet basis and the number of decomposition layers, and obtaining a corresponding wavelet coefficient, obtaining a threshold value through calculation based ona threshold value selection algorithm, and performing threshold value processing on the wavelet coefficient based on the threshold value to obtain an estimated wavelet coefficient, reconstructing theestimated wavelet coefficient to obtain an estimated value of the partial discharge signal of the power cable, performing H-order cross overlapping differential transformation on the estimated value of the partial discharge signal of the power cable, and obtaining the transformation quantity of the partial discharge signal of the power cable through calculation, and obtaining an average energy value and a maximum value of t