High-speed output short-circuit protection method for multilevel PWM AC/DC converter

A new method that protects against a load short-circuit in a multilevel PWM AC/DC converter is described. The output DC voltage of the proposed scheme can he quickly disconnected from the short-circuit load. In addition, the DC voltage is applied to the load immediately after the fault has been cleared without causing any voltage overshoot. The proposed scheme has the advantages of a simple structure, low cost and low volume. Experimental results are presented to verify the usefulness of the proposed scheme.