This paper addresses premature bearing failure and reduced motor reliability in PWM inverter-driven systems caused by excessive bearing voltage, stemming from capacitive bearing currents and Electrical Discharge Machining (EDM) effects. It analyzes the mechanism: high-frequency common-mode voltage (CMV) from inverter switching couples to bearings via motor stray capacitances. The Advanced Zero Sequence PWM (AZSPWM) is studied, which suppresses CMV amplitude and high-frequency components by optimizing switching sequences to eliminate specific zero-sequence harmonics. An active hardware method based on a novel common-mode transformer (CMT) is proposed, using the motor rotor shaft as its secondary winding to dynamically detect bearing voltage and inject a compensating voltage of equal magnitude but opposite phase to cancel common-mode current. Combining them forms a synergistic mechanism. Simulations and experiments show it significantly reduces bearing voltage peak and high-frequency oscillations, suppresses bearing current, and lowers electrical erosion risk, providing an effective solution to enhance motor reliability and lifespan.