多路独立输出隔离直流电源的故障保护研究

随着电子设备的不断复杂化，多路输出电源需求加大，但传统的多路输出电源往往存在拓扑与控制策略复杂、辅路输出电压供电质量较差等问题。提出一种新型的两级式多路输出电源，并针对负载端的过载故障与输入端的掉电故障研究相应的保护电路。电源前级LLC谐振电路实现电压的隔离转换与输出稳压控制，后级多路功率开关电路实现输出通道的扩展，并实现每路输出的独立控制与独立过载保护。此外，研究励磁电感可变的变压器，通过变电感控制有效增长电源掉电保持时间。最后，设计一台28 V输入、5路15 V输出的75 W直流电源，搭建实验样机验证了理论分析的正确性。

Research on Fault Protection of Isolated DC Power Supply with Multiple Independent Outputs

With the increasing complexity of electronic devices, the demand for multi-output power supplies has increased. However, the traditional multi-output power supply often has problems such as complex topology and control strategy, and poor power quality of auxiliary output. A novel type of multi-output power supply with two stages is pro-posed, and the corresponding protection circuits against overload fault at the load end and power failure at the input end are studied. An LLC resonant circuit at the front stage is used to realize voltage isolation conversion and stable output voltage, and multiple power switches at the back stage are used to realize the expansion of the output channel. Mean-while, independent control and independent overload protection of each output are realized. In addition, the transformer with variable magnetizing inductance is studied, and the hold-up time is effectively increased through variable induc-tance control. Finally, a 75 W DC power supply with 28 V input and five-channel 15 V output was designed and its ex-perimental prototype was built, which verified the theoretical analysis.