Hybrid matrix converter based on instantaneous reactive power theory

A matrix converter is a single-stage direct AC/AC converter. By employing only nine bidirectional switches, the matrix converter is able to generate variable amplitude and frequency output voltages. Matrix converters would inject a significant amount of current harmonics and voltage harmonics back in to the power source and the load, respectively, if filtering measures are not properly implemented. These harmonics cause distortion and adversely impact the operation of the whole system. The increasing demand for high power makes the conventional solution of passive filters no longer sufficient to solve the power quality problem in matrix converters, beside the other drawbacks of using bulky passive components such as, short life time, big size, and high cost. This paper presents a hybrid matrix converter for medium voltage high power applications. By utilizing a low-frequency modulation techniques, combined with a shunt active filter implemented to the input side of the matrix converter to eliminate current harmonics and a series active filter is applied to the output side of the matrix converter to eliminate the voltage harmonics. This approach is more efficient in terms of reducing the total number of passive components used in the system, reducing the switching power losses, and improving voltage transfer ratio. The explanation of predicting the compensation current and the compensation voltage waveforms is based on the instantaneous reactive power theory. The feasibility and effectiveness proposed topology have been verified by the simulation results.