Online Junction Temperature Measurement via Internal Gate Resistance Using the High Frequency Gate Signal Injection Method

In many power electronic applications, it is important to monitor the junction temperature of the power semiconductor devices. This enables for example an abnormal temperature protection, lifetime monitoring or junction temperature control. This paper proposes an online junction temperature measurement based on the internal gate resistance as a temperature sensitive electrical parameter. A direct measurement of this resistance is not possible. Therefore, a high frequency signal is injected into the gate circuit to measure the gate circuit's impedance, which includes the temperature sensitive internal gate resistance. This paper focuses on a simple realization of this method.