A PAC based current feedforward control for three-phase PWM voltage-type converter

Abstract

This paper presents a novel current feedforward control strategy for a three-phase pulse-width modulation (PWM) DC voltage-type converter based on phase and amplitude control (PAC). With right-angle triangle relation of phasors and principle of conservation of energy, a phasor adjustment method and the relevant low-frequency mathematical model of the system are analyzed in detail, both in rectification and regeneration modes for the converter, are discussed. For improving the traditional PAC dynamic performance, variable load current is detected indirectly by the change of the DC voltage, which is fed to the control system as an additional control variable to generate modulation index and phase angle. Also, the algorithm is derived and the system principle is introduced. Experimental results from a 3 kw laboratory device are included to demonstrate the effectiveness of the proposed control strategy.

The improved PAC method for a three-phase PWM grid-connected inverter

“…However, comparing with the direct current control, its current dynamic response is not very fast. Recent research about PAC mainly involved in improving the dynamic performance of the system in operation and design of system parameters [2,7] . None of them refer to improving startup the dynamic performance of the system.…”