Patent ID: 9612269
Date: 2017-04-04
CPC Classifications: G01R,H02H

Claim:
1. A method for detection of a ground fault in high resistance ground network, comprising: in a voltage source power conversion circuit comprising a power converter that converts incoming AC power to DC power applied to a DC bus and an inverter that converts DC power from the DC bus to output AC power, detecting a midpoint-to-ground voltage based on a low side potential of the DC bus and a ground potential; receiving the detected midpoint-to-ground voltage via a monitoring and analysis circuit; determining, via the monitoring and analysis circuit, whether each of a line side ground fault in a phase of incoming AC power, a load side ground fault, and a DC bus ground fault exist in the high resistance ground network based upon the detected midpoint-to-ground voltage, wherein the determination occurs prior to powering a load with the output AC power; and determining, via the monitoring and analysis circuit, whether each of a line side ground fault, a load side ground fault, and a DC bus ground fault exist in the high resistance ground network based upon the detected midpoint-to-ground voltage, wherein the determination occurs during powering the load with the output AC power.