Development of a Three-Phase LCC Resonant Converter with a High-Voltage Rise Ratio for the Power Processing Unit

In this paper, a three-phase LCC resonant converter is designed to meet the operating requirements of a high boost ratio, wide output range, and stable output power for the screen-grid power supply of an ion thruster with a single-stage structure. Since the converter operates in three-phase interleaved mode, the output voltage ripples cancel each other, reducing the output capacitor capacity greatly and suppressing the arc energy of the inter-screen grid fault discharge fundamentally. In addition, a wide range of voltage outputs can be realized by controlling the converter to operate in three different modes: half-bridge, full-bridge, and three-phase interleaved. Finally, the experimental prototype accomplished the design specifications of 1kV/500W, efficiency of 92%, voltage ripple of 0.6%, and 8.5mJ energy storage in the output capacitor.