A high performance auxiliary power supply (APS) with multiple isolated outputs plays a crucial role in ensuring the effective operation of power converter systems. An isolated resonant current source converter is usually adopted as the APS in medium-voltage (MV) applications with the advantages of low coupling capacitance and high insulation strength. In this paper, a Class E-based multichannel APS, featuring a low component count, modular circuit structure and ease of scalability to multiple output channels, is proposed. The operation principle of the proposed circuit is presented in detail. To overcome the cross-regulation problem in multiple outputs, an individual hysteresis control approach is introduced to regulate each output separately and decouple the multiple outputs. The converter performance under open/short-circuit fault conditions is also explored with the proposed control scheme. Design considerations, including the zero-voltage-switching (ZVS) realization and the output power capabilities, are presented, together with a step-by-step parameter design approach. Finally, an 8 output APS experimental prototype (with different output voltage levels) is presented. The experimental results demonstrate the output voltage decoupled regulation and load independent ZVS performance of the prototype.
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