抄録
This paper proposes a new control method for a high-frequency cycloconverter consisting of two half-bridge inverters and a series-resonant circuit. This cycloconverter acts as an ac-to-ac direct power conversion circuit without any dc stage. This circuit does not require a diode bridge rectifier, and thus, can be used to reduce forward voltage drops and power losses in the diodes. A new phase-shift control method is proposed to regulate the capacitor voltage in each half-bridge inverter and to achieve zero-voltage switching. The proposed phase-shift control is theoretically discussed and is also verified by an experimental circuit consisting of super-junction power MOSFETs. As a result, the proposed high-frequency cycloconverter exhibits a good power conversion efficiency as high as 97.7% at the rated power of 1.3kW.
