Patent ID: 7233465
Filing Date: 2007-06-19
Classification: H02H,H02M

Abstract:
1. A ground fault detection method for an inverter, comprising: setting a reference value for detecting a ground fault; comparing a current value calculated by summing current values of each of a plurality of phase currents flowing through an output terminal of the inverter with the reference value for detecting the ground fault; determining that a ground fault exists when the calculated current value is larger than the reference value; determining a phase in which the ground fault exists on the basis of a current difference value between start and end points of 0 vector sections of each phase or between start and end points of 7 vector sections of each phase; setting a zero vector band which is a reference value for a size difference of each of the plurality of phase currents in application of 0 voltage vector and 7 voltage vector; increasing current information by adjusting a detection frequency of each of the plurality of phase currents; and equalizing a phase of a voltage reference value to a phase of a current reference value.