Vibration characteristic analysis of low-frequency fast circuit breakers based on improved EWT

The violent vibrations generated during switching of low-frequency fast circuit breakers （LFFCBs） can potentially impact their mechanical performance. However， there is currently a lack of assessment methods for evaluating the effects of these vibrations. It is necessary to introduce an approach for vibration characteristic testing and analysis that characterizes the mechanical performance of LFFCBs to improve their operational reliability. To this end， the vibration signal test of LFFCBs during the switching process is carried out， and the time-frequency characteristics of the vibration signal are analyzed based on the improved empirical wavelet transform （EWT） and Hilbert transform. The findings indicate that the EWT with spectrum partitioning being improved can more accurately obtain multiple modal components of the vibration signal during the LFFCB switching. Furthermore， there are significant differences in the distribution characteristics of the energy spectrum at different locations of the vibration signal.