| Abstract |
A new method for junction temperature measurement of power semiconductor switches is presented. The method consists of integrating the gate voltage of an IGBT or MOSFET during the turn-on or turn-off delay, which in turn produces an output measurement voltage that fluctuates due to the temperature dependent resistance of the temperature sensitive electrical parameter (TSEP): the internal gate resistance. The measurement circuit can be integrated into a gate driver with no modification to converter or gate driver operation and holds significant advantages over other TSEP based measurement methods, primarily being: an absence of any dependence on operating conditions such as load current, and the potential to achieve higher sensitivity (20mV/C or more) than alternative other TSEPs. The measurement circuit is successfully implemented in a double pulse test and is able to produce a measurement voltage dependent on the junction temperature of an IGBT module. |
