Numerical Simulation of Propagation Process of Acoustic Emission Partial Discharge Signal in Medium Voltage Switch-Gears

Abstract

The rapid and accurate detection of partial discharges (PD) ensures the safe operation of the power grid. It is important to improve the reliability of power supply. When a partial discharge (PD) occurs, acoustic wave will be produced. Usually the partial discharge (PD) produces an acoustic wave frequency of about a few kHz in the gas. This article will use the acoustic simulation module in the Comsol Multiphysics software to simulate the propagation of ultrasonic waves inside and outside the switchgear. Since the transmission of ultrasonic waves is affected by many factors, the geometry of the switchgear is the main factor affecting the propagation of ultrasonic waves. Therefore, this paper will simulate the transmission process of ultrasonic waves under different conditions. Exploring the impact of different monitoring locations on monitoring results through simulation. Through the analysis of the simulation results of the ultrasonic propagation process, we got the following conclusions. As the thickness of the switchgear cabinet increases, it only affects the amplitude of the signal. Opening a hole in the cabinet of the switchgear makes it easier to detect ultrasonic signals outside the cabinet. As the number of openings in the cabinet of the switch cabinet increases, the amplitude of the signal monitored outside the cabinet increases. Four monitoring points are placed on the front, back, upper and lower sides of the switchgear cabinet. Through the simulation of the ultrasonic transmission process, it can optimize ultrasonic testing method and provide guidance for the detection method of ultrasonic waves in production activities.