宽可调电压范围的交直流精密电源

Wide-range adjustable AC/DC precise power supply

详述了电源的主电路拓扑结构及其控制策略,分析了常规电路存在的驱动信号不正常和输出电压削顶的问题,分别给出了限定驱动信号占空比和提高三角波对称性的解决措施.针对宽电压范围和交直流两用的应用特点,提出了两级开关电源联动调节的方案,即根据不同幅值的电压输出改变相应的前级母线电压.理论分析了在中小幅值输出时该方案对减小输出纹波是可行的,并结合数字控制方法设计了两级的联动配合调节.通过了一台试验样机验证了上述设计和分析.电路试验结果表明所提出方法对提高电源性能效果显著,切实可行.

The topology and control strategy of the wide-range adjustable AC/DC power supply circuit were described. The abnormality of driver signals and the voltage output distortion existed in conventional circuits were analyzed, and schemes of limiting duty ratio and improving the symmetry of carried wave were introduced to overcome those problems. To reduce switching ripple of output current, an idea of double-stage linkage was proposed in which the voltage output of the front-stage was regulated to support the change of inverter voltage output. The effectiveness of the proposed idea was analyzed on the basis of the fundamental theory. Then a scheme was devised to carry out this idea with the digital control technology. The analysis and the proposed methods are verified by circuit experiment. Comparison shows that the proposed power supply has better performance than traditional one.