Patent ID: 8472153
Filing Date: 2013-06-25
Classification: H02H

Abstract:
1. A fault detection, identification, and protection system for a neutral point clamped (NPC) power converter, said fault detection, identification, and protection system comprising: a phase leg of the NPC power converter, the phase leg comprising two NPC diodes, two inner switches with two associated inner diodes, and two outer switches with two associated outer diodes, each of the inner and outer switches of the phase leg having a respective gate driver, wherein each of the outer switches are connected to a respective bus of the phase leg, and the inner switches are connected in series between the two outer switches; a fault detection circuit, the fault detection circuit configured to determine, based on signals received from the two inner switches and two outer switches via their respective gate drivers, the presence of a fault in the phase leg; a fault identification circuit, the fault identification circuit being configured to determine, based on signals from the fault detection circuit, a location of the fault in the phase leg; and a protection circuit, the protection circuit being configured to turn off at least one of the inner switches or outer switches in response to the identification of the location of the fault by the fault identification circuit.