Fluctuating current control for a PMSM under reduced DC link capacitance

The DC link voltage fluctuation problem is more serious for an inverter system which utilizes a single phase AC source. As an effort to reduce the DC link capacitance, the fluctuating motor power control is proposed to match the converter power. Specifically, the key idea is to enforce current oscillation along a constant torque line which only affects the reactive power of the motor. Analytic method for obtaining the current bounds was derived. Also, a practical recursive algorithm was proposed. Simulation and experimental results support the effectiveness of the proposed method.