A dual-bridge inverter approach to eliminating common-mode voltages and bearing and leakage currents

This paper presents a dual-bridge inverter approach to eliminate the motor common-mode voltage and resulting bearing and leakage currents. The novel dual-bridge inverter is controlled to generate balanced excitation of the induction motor under pulsewidth modulation (PWM) inverter operation. Theoretical analysis, simulation results, and experimental results are presented to verify this concept. Index Terms - Adjustable-speed drive, bearing current, common-mode voltage, drives, leakage current, shaft voltage.