Online junction temperature estimation of IGBT modules for Space Vector Modulation based inverter system

This paper presents a junction temperature estimation model for space vector modulated IGBT inverter system for a real time implementation. Advances in power electronics, control systems, motor drives, and electrical machines helped in developing new technologies of Variable speed constant frequency (VSCF) system for more aircraft application. It is estimated that about 21% of the faults in the variable speed drive system are due to failure of power devices, Most of the inverters use insulated gate bipolar transistor so these applications require well designed thermal management systems to ensure the protection of IGBTs from thermal runaway. Therefore estimating the junction temperature has become essential to predict the fault and to assist in IGBT heath monitoring system. The proposed junction temperature estimation method is based on the power loss approach. Electro-thermal models for the commonly used Space Vector Modulation (SVM) techniques namely the alternate SVM and the Null V0V7 SVM are developed. The efficacy of the proposed junction temperature estimation model is verified using the measured junction temperature from the experimental setup.