Switch fault diagnosis using S-transform on three phase inverter for BLDC drive

Abstract

BLDC drives are highly preferred for electric vehicles application because of its less maintenance, longer life, lower weight and reliability. Normally for electric vehicles the motors are powered by batteries, so three phase inverter is very important in driving the motor. The closed loop system is highly efficient in controlling the parameters of the drive but any fault occurring inside the system may lead to abnormalities which can damage the entire system. So due to this, the fault analysis on the BLDC drive system is very important. As three phase inverter is important in driving the motor, in this project we are going to perform fault diagnosis on three phase inverter in BLDC drive system. The commonly occurring faults in the switches are open circuit and short circuit faults. There are different methods for diagnosing switch open and circuit faults but S-Transform analysis proves to be the best method in providing better results compared to the conventional methods. So in this paper the fault diagnosis on three phase inverter is done using S-Transform method to accurately find where and which type of fault has occurred.