多路精密稳压电源的研究

在传统多路输出开关电源中,存在输出电压交叉调整率低和辅助回路稳压精度差的难题。针对此问题,详细分析了磁放大器稳压原理和基于磁放大技术的有源箝位正激变换器工作特性,提出了一种基于固定占空比、峰值控制模式、磁放大器调节的多路输出有源箝位软开关正激变换器。该拓扑电路具有成本低、结构简单、效率高、输出电压交叉调整率高的优点。研制了一台基于该技术的样机,开关频率为45 kHz,额定输入直流电压220 V,输出5 V/10 A和24 V/2 A的开关电源。该样机满载效率为88.9%,全负载范围内交叉调整率为0.5%,验证了该方案的合理性。

Research on Multi-output Precision Regulated Switching Power Supply

In the traditional multi-output switching power supply,poor cross-regulation and low regulation accuracy of auxiliary winding are difficult problem.To solve this problem,the working principle of magnetic amplifier and the operating characteristics of active clamp forward converter are analyzed,then a new multi-output soft-switching activeclamp converter is proposed which based on a fixed duty cycle,peak control mode and the magnetic amplifier technology. A 45 kHz,DC 220 V input,5 V/10 A and 24 V/2 A output DC/DC module is designed based on this technology. 88.9%efficiency is achieved at full load,cross-regulation is 0.5%in entire load range.Experimental results verify the reasonableness of the scheme.