Fault Diagnosis of On-Load Tap Changer Based on Optimized Empirical Modal Decomposition Algorithm

In order to effectively monitor the operation of the on-load tape-changer (OLTC) online, an optimized empirical mode decomposition algorithm based on improved mask signal is proposed to analyze the vibration signals on the surface of the switched on load changers. An improved mask signal is added to the collected original signal, which can effectively eliminate the modal aliasing in the process of Empirical Mode Decomposition. Then the maximum power characteristic matrix is obtained according to the decomposed intrinsic mode function (IMF), further monitoring condition of the on-load tap switch. The results show that the maximum power characteristic matrix of OLTC in different operating states has obvious difference. When different typical faults occur in OLTC, the interval maximum power characteristic matrix index can effectively discriminate the degree of vibration signal difference.