| 摘要 |
A system and method for detecting ground faults in an AC motor drive is disclosed. A fault detection and protection system for an AC motor drive includes current sensors to measure first and second phase output currents, a voltage sensor to measure a DC link voltage, and a desaturation control circuit to determine a voltage and associated current across PWM inverter switches for a third phase of the output. A controller compares the first and second phase currents, the measured DC link voltage, and the voltage across the PWM inverter switches on the third phase, to a plurality of thresholds. The controller detects a ground fault on one of the first, second, and third phases of the three phase output to the AC motor based on the comparisons of the first and the second phase currents, the DC link voltage, and the voltage across the switches to the thresholds. |
