Abstract:

The auxiliary power supply of marine equipment has multiple power supply level, a large number of cables, and long cable routes, which leads to great difficulty in the selective protection of the system. Using the auxiliary power supply high-voltage power extraction can effectively solve the above problems. Taking the high-voltage-input low-voltage-output DC auxiliary power supply as the research object, aiming at the characteristics of high-voltage-input the high-voltage main power conversion circuit based on three-level half-bridge circuit is designed. In order to realize the self-excited start-up, a high-voltage auxiliary power supply with dual-channel switching of capacitor extraction power and feedback power supply is designed. Finally, a prototype with a rated power of 2 kW is fabricated, and the experimental results verify the feasibility and correctness of the design scheme.

Key words: high-voltage-input, low-voltage-output, DC auxiliary power supply, three-level half-bridge, self-excitation start-up