Proportional-resonant control of a single-phase to three-phase converter without electrolytic capacitor

A large electrolytic capacitor is always used to make dc-link voltage stable in a single-phase to three-phase power converter. However, the large electrolytic capacitor occupies a large volume and has a short lifetime as to the home appliances. And additional PFC circuit is needed to correct the grid current. In order to settle these issues, a converter without electrolytic capacitor is studied in this paper. The q-axis current reference is modified for the high grid power factor operation. And the d-axis current reference is generated to achieve the flux-weakening control and to improve the waveform of the output currents and. Proportional-resonant controllers are adopted to obtain the better current performance. The simulation results verify the validity and feasibility of the proposed method.