I. Introduction
In renewable energy generation and motor drive applications, three-phase power converters are widely used. For conventional motor drive systems, the three-phase power converter consists of a passive diode front-end that interfaces with the power grid, a dc-link capacitor, and a voltage-source inverter (VSI) that drives the motor [1]. To improve the power quality on the grid side, active front-ends have obtained increased popularity, which normally consists of a voltage-source rectifier (VSR) [1]–[4] to form the back-to-back VSR–VSI scheme in Fig. 1(a). The VSR–VSI combination is also commonly found in renewable power generation systems that require improved current waveforms on both the generator and grid sides [5].
Schematics of (a) VSC (consisting of VSR and VSI) and (b) CSC (consisting of CSR and CSI).