Power Fluctuation Suppression Strategy for Electrolytic Capacitorless IPMSM Drives

-The fluctuation of DC-link voltage can cause fluctuations in the motor current and voltage at corresponding frequencies, affecting the output power of the motor. This article proposes a power fluctuation suppression strategy based on the harmonic injection, which adapts to the DC-link voltage fluctuations under maximum torque per ampere (MTPA) control. By injecting harmonics that characterize power fluctuation characteristics into the d-axis current, the harmonics caused by the DC-link voltage ripples in the input power can be reduced. This method can reduce motor power fluctuations and improve the motor output characteristics.