[Objective] Traditional permanent magnet synchronous motor drives are limited by the thermal degradation characteristics of electrolytic capacitors

resulting in a lifespan bottleneck. Electrolytic capacitor-less drive systems improve reliability by replacing electrolytic capacitors with film capacitors

but the large inductors introduced can easily cause LC resonance on the grid side. To address this

this paper proposes a virtual damping power control method that effectively suppresses grid-side resonance and enhances the system’s power factor and power quality. [Methods] To investigate the influencing factors of grid-side LC resonance

the characteristic equation of the electrolytic capacitor-less drive system was derived

and the necessity of increasing system damping to suppress resonance was clarified. The traditional virtual impedance control scheme was optimized

and the corresponding relationship between bus capacitor power

grid-side inductor power

and resonant power was established based on energy conservation and space vector pulse width modulation control cycles. By accurately calculating the resonant power and converting it into a voltage vector for compensation

effective suppression of resonance was achieved. [Results] The experimental results demonstrated that the proposed method effectively suppressed grid-side LC resonance under both rated and high-speed operating conditions. The total harmonic distortion of the grid-side current was significantly reduced

and the system power factor reached a maximum of 0.99. [Conclusion] The proposed method provides a reference for the engineering application of electrolytic capacitor-less drive systems in low-cost and high-reliability fields.