Stray Inductance Extraction of High-Power IGBT Dynamic Test Platform and Verification of Physical Model

Stray inductance has an important influence on the characteristics of power electronic devices as well as switching devices themselves. Influenced by stray inductance, the insulated gate bipolar transistor (IGBT) induces high voltage peak in the switching transient process. The high-voltage peak will affect the reliability of a power electronic device like inverter. Considering the switching transient is most beneficial to the extraction of stray inductance and based on the integrating method, this paper proposes an appropriate method of extracting the stray inductance for a high-power IGBT dynamic test platform. The IGBT dynamic test platform made by LEMSYS is used to test the 3.3kV/1.5kA IGBT module under different load conditions. Then its loop stray inductance and parasitic inductance are extracted by the proposed method. Finally, the established lumped charge physical models of IGBT and fast recovery diode (FRD) are applied to verifying that the proposed method is practicable and effective.