Performance analysis of a power factor compensator which simultaneously eliminates line current harmonics

摘要

The performance and dynamic characteristics of a solid-state power factor compensator which simultaneously eliminates line current harmonics are presented and analyzed. Power factor compensation is achieved by controlling the magnitude and the phase angle (delta) of the transistorized PWM inverter output voltage. Fast response times are obtained by adjusting the amplitude of the PWM inverter output voltage through a modulation index control. The principal advantage of this scheme is that it can maintain a near unity mains overall power factor without sensing and computing the associated reactive components. It can also substantially reduce the harmonic content of the line current when the load is nonlinear. A time domain model is derived and used to accurately predict dynamic behavior and stability region, and to adjust system controllers. The transfer function of the power factor compensator is obtained. Experimental results confirm the operation characteristics obtained by computer simulation and analyses.