基于虚拟阻尼功率控制的无电解电容驱动系统谐振抑制方法OA

[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.