Control of a single-stage three-phase boost power factor correction rectifier

Abstract

Advances in power electronics are enabling More Electric Aircrafts (MEAs) to replace pneumatic systems with electrical systems. Active power factor correction (PFC) rectifiers are used in MEAs to rectify the output voltage of the three-phase AC-DC boost converter, while maintaining a unity input power factor. Many existing control strategies implement PI compensators, with slow response times, in their voltage and current loops. Alternatively, computationally expensive nonlinear controllers can be chosen to generate input currents with high power factor and low total harmonic distortion (THD), but they may need to be operated at high switching frequencies due to relatively slower execution of control loop. In this work, a novel control strategy is proposed for a three-phase, single-stage boost-type rectifier that is capable of tight and fast regulation of the output voltage, while simultaneously achieving unity input power factor, without constraining the operating switching frequency. The proposed control strategy is implemented, using one voltage-loop PI controller and a linearized transfer function of duty-ratio to input current, for inner loop current control. A 1.5 kW three-phase boost PFC prototype is designed and developed to validate the proposed control algorithm. The experimental results show that an input power factor of 0.992 and a tightly regulated DC link voltage with 3% ripple can be achieved.