Power cycling testing with different load pulse durations

For many applications, the impact on the component lifetime of temperature swings generated by low output frequency is of special interest. Therefore, active power cycling tests with a variation of load pulse duration were conducted. The requirements for the active power cycling test equipment related to load pulse durations down to 70 ms are discussed. The analysis of the test results leads to the proposal of a new empirical lifetime model for advanced power modules, which explicitly contains the impact of the load pulse duration. These reliability results will affect the design of advanced inverters with low-frequency output currents.