Operation of power semiconductors under transient thermal conditions: thermal fatigue reliability and mechanical aspects

摘要

The authors explain the degradation mechanism of a TRIAC submitted to the application of strong di/dt during the commutation at turn-on. The analysis is based on the evaluation of the thermo-mechanical forces concerned in the Initially Turned on Area of the TRIAC in quadrant Q2. A mathematical expression is established giving the number of commutations cycles before failure that the component can withstand. This expression is made profitable to evaluate the reliability of the TRIAC.