Indirect matrix converter with unity voltage transfer ratio for AC to AC power conversion

Having a voltage transfer ratio lower than unity with a 0.866 upper limit, even lower than 0.866 in the course of experiments because of parasitic components of real power circuits, is one of the shortcomings of matrix converters. This deficiency is one of the greatest impediments to industry adaptation of matrix converters. To surmount this barrier this paper proposes a novel modification in circuit topology of indirect matrix converters (IMC) achieving voltage boosting and unity voltage transfer ratio. Besides preserving the inherent advantages of the conventional matrix converters, such as controllability of input power factor, sinusoidal input/output currents and the ability of bidirectional power flow, the remarkable feature of this solution is that, unlike the other research in this field no special control strategy or additional reactive elements at the DC-link is used and the integrity of the converter has been kept as much as possible. Furthermore a new efficient switching strategy is proposed for the new converter. Simulation results are shown to support the given theoretical analyses and experimental results obtained from a 5 kW converter verify the full functionality of the proposed topology.

► A practical solution for overcoming the voltage transfer ratio limitation in indirect matrix converters is proposed.
► No additional reactive elements are used at the DC-link and the integrity of the converter is kept.
► The quality of the input and output currents meet the IEC requirements under the unity voltage transfer ratio.
► Functionality of the proposed converter is fully tested with simulation and a 5 kW prototype.