Design of LC filter with closed loop technique to shape input current of single phase matrix converter

This paper presents single phase matrix converter (SPMC) topology capable of generating a higher output frequency which is used for high frequency applications such as induction heating. Proposed configuration reduces total harmonic distortion (THD) of supply current with the injection of LC resonant filter at the supply end. By the analysis of dominant side band components of the supply current, the resonant LC filter is chosen. The cutoff frequency of filter transfer function is estimated through the bode plot. However, at a low output frequency (less than 1kHz), the filter is only able to reject higher order components, but lower order harmonics mainly 3
^rd
& 5
^th
order components still exist in the input current. This demands a closed loop control technique for removing lower as well as higher order component simultaneously. Closed loop control of SPMC shapes the input current in sinusoidal nature at a low output frequency less than 1kHz. But the spikes arise in higher output frequency and affects the switching stress. To avoid the spikes and make the active current shaping purely sinusoidal at any output frequency, LC filter is inserted at the supply end. The proper switching technique to eliminate the commutation problem is explained in details. The simulation results of this topology are verified by using MATLAB/SIMULINK.