Design and control of an LCL-filter based three-phase active rectifier

The aim of the paper is to propose a design procedure for an LCL-filter in a front-end three-phase active rectifier. The main goal is to ensure a reduction of the switching frequency ripple at a reasonable cost and, at the same time, to obtain a high performance rectifier. In this paper a step-by-step procedure for designing an LCL-filter is proposed and verified by simulations and experiments. An example of LCL-filter design has been reported and, with the obtained values, the filter has been realised and tested. The experimental results demonstrate the effectiveness of the design procedure both of the LCL-filter and of the controllers. The performance of the overall system is good both in the low and high frequency ranges. Moreover the good agreement between these results and those obtained in simulation validate the adopted model: the design procedure and the simulation model represent a powerful tool to design an LCL active rectifier without the need for the realisation of several prototypes.