Inverter IGBT loss analysis and calculation

This paper presented an analytical method to calculate the inverter IGBT loss and water cooling system. In the implementation process, the effect of gate drive resistor, DC bus voltage, temperature and junction temperature on the IGBT loss were taken into comprehensive consideration for the first time. The method to calculate inverter IGBT and Diode conduction loss, switching loss, total loss, efficiency, temperature difference and junction temperature were given under the SVPWM modulation algorithm. Taking the interaction characteristics of the IGBT loss and junction temperature into account, the interaction of the loop algorithm was presented on the initial condition of the ambient temperature using the custom thermal circuit model, the IGBT junction temperature, case temperature and radiator temperature curve were given finally. On this basis, a medium voltage variable frequency speed control system with water cooling system was designed, it is in good agreement with experimental values, which affirmed the accuracy of the analytical method and verified the correctness and feasibility of the method.