Brian P. Brown

Junction Temperature Prediction of a Multiple-chip IGBT Module under DC Condition

This paper develops a thermal model for a six-pack insulated gate bipolar transistor (IGBT) power module operating as a three phase voltage source inverter. With this model, the temperature of each chip can be derived directly from the losses of the silicon chips and a thermal impedance matrix. The losses of each chip can be calculated through the voltage and current information of the power module. The impedance model can be easily transferred into a micro-processor to predict the online chip temperatures. It largely increases the temperature accuracy when the inverter operates at zero or low output frequency. Theory analysis, simulation and experimental results are provided to verify the effectiveness of this model

Mitigation of the effects of common-mode current on the operation of SCR-based rectifiers for AC drives

Common-mode current generated by the PWM AC drive at low modulation index and higher switching frequency results in overheating of the pre-charge resistor of the SCR based rectifier. In this paper, two modifications are proposed for the operation of SCR based rectifiers to significantly reduce the resistor overheating issue. The solution is cost and size effective when compared with alternative solutions. Experimental results are provided to show the reduction of common mode current flow through the pre-charge resistor and the consequent reduction in its temperature.

Mitigation of the Effects of Common-Mode Current on the Operation of SCR-Based Rectifiers for AC Drives

Common-mode current generated by the pulse-width modulated (PWM) ac drive at low modulation index and higher switching frequency results in overheating of the precharge resistor of the silicon-controlled rectifier (SCR)-based rectifier. In this paper, two modifications are proposed for the operation of SCR-based rectifiers to significantly reduce the resistor overheating issue. The solution is cost and size effective when compared with alternative solutions. Experimental results are provided to show the reduction of common-mode current flow through the precharge resistor and the consequent reduction in its temperature.