Power module protection at start-up

摘要

A power conversion unit includes a power converter and a controller coupled to the secondary or output stage of the power converter. The power conversion unit is configured to generate an output test voltage or current during a pre-start test period of the power converter, where the output test voltage or current is monitored to determine a converter fault condition. A method of operating a power conversion unit is also included.

主权项

1. A power conversion unit comprising:
a power converter having a primary stage and a secondary stage, the primary stage including a pulse width modulated (PWM) circuit; an isolation barrier separating the primary stage from the secondary stage such that primary stage information is unavailable to the secondary stage; and a voltage controller located in the secondary stage and configured to test the power converter and a load coupled to the power converter for a fault condition by driving the PWM circuit to produce an output test voltage at the secondary stage during a pre-start test period of the power converter; wherein the output test voltage beyond a predetermined threshold value is indicative of a fault condition.