A new control strategy for improving the transient performance of PWM AC-DC converters

In this paper, another approach to current control of voltage type PWM AC to DC converters with phase and amplitude control is presented. This approach is based on state feedback control of a filter reactor present on the AC side to not only compensate the offset current but also eliminate the waveforms oscillations. Stability analysis to determine an optimum set of feedback coefficients is carried out. The experimental results of the proposed system show that the transient waveforms are improved greatly and that the dynamic response can be made significantly quick even if DC side capacitance is substantially reduced.