A modular Parallel-Input Series-Output (PISO) CLL resonant converter has been designed for the Magnetron application. Each High-Voltage (HV) module generates 1kV at the output. To reduce the number of semiconductor devices, each HV module consists of a half-bridge inverter and a diode voltage-doubler rectifier. In addition, to reduce the overall size of the converter, planar magnetics along with a high switching frequency have been used in the resonant tank. To achieve a smooth soft-start and a wide voltage gain profile throughout the whole loading spectrum, a multi-mode operation has been incorporated in the design of the control system. All the switches and diodes are able to achieve soft-switching to enhance the circuit efficiency. Preliminary experimental results are also provided on a 300VDC/4kVDC 1600W proof of concept prototype to highlight the merits of the proposed converter.
