低電壓大電流軟開關電源的設計

摘要：本文介紹了一種大功率低壓大電流開關電源的設計方案,該電源滿載輸出功率為60kW（5000A/12V），采用軟開關移相全橋控制方式,實現了零電壓軟開關;控制電路中采用了穩壓穩流自動轉換方案，實現了輸出穩壓穩流的自動切換，提高了輸出性能;采用多個變壓器串并聯結構，使并聯的輸出整流二極管之間實現自動均流;設計并使用了容性功率母排，減小了系統中的振蕩，減小了功率母排的發熱，達到了令人滿意的實驗結果。 敘詞：移相FB-PWM, 軟開關, 無感功率母排, 變壓器 Abstract：This paper presents one design of switching power supply which is high power, low voltage and high current, the full load output power of which is 60kW(5000A/12V). The strategy of phase-shifted soft-switch full-bridge control is applied in the power supply, which realizes zero-voltage soft switching. The control circuit adopts the strategy of automatic conversion with steady voltage and steady current, which results in the automatic shift of output steady voltage and steady current, thus improving the output quality. The power supply uses multi-transformer-series-parallel structure, which results in the automatic load sharing among each output rectifier diode that is paralleled. And the performance is observably improved by inductance-less power bus. Keyword：shifting phase PWM, soft switching, inductance-less power bus, transformer