Power quality improvement of indirect matrix converter input currents using a small DC link filter

A new filter topology and control system to improve input current waveforms of Sparse Matrix Converters (SMC) is presented. The topology is based on an Indirect Sparse Matrix Converter fitted with input ac filter, aided by a small dc link 2^nd order filter, with smaller parameters compared to the ac input filter. The control system is designed to regulate the input current and dc link capacitor voltage, with the objective of keeping constant the input id current component, while keeping the iq component close to zero, to obtain near unity input power factor. The filter design and control performance is validated by numerical simulations, and compared to a similar converter without the dc filter.