输出电压可宽范围调节的开关电源实现策略

Realization of SMPS at wide-range output regulatory voltage

为解决微等离子体氧化工艺所用电源的输出电压必须在很宽范围内调节的问题,提出一种利用PWM控制和频率调节相结合的单级式、单拉输出电压宽范围调节实现策略,即电源在绝大部分运行时间内以PWM控制方式工作,而在恒频方式难以实现的低压范围则采用PWM控制与频率调节相结合的控制方式。在不增加电路复杂程度的基础上,实现了输出电压在较宽范围内调整(45-700 V),既解决了典型PWM控制方式开关电源输出电压调整范围窄的问题,又减小了开关频率的变化范围、降低了输出电压纹波。实际运行效果证明了这种方法的有效性。

A realization strategy of single-stage and single-control wide-range output voltage circuit is proposed to meet the requirements put forward by micro-plasma oxidation. This makes the power supply run in PWM mode in most part work-time, but only in the low voltage range that PWM mode cannot realize ran in PWM and frequency regulation common mode. Combining PWM with frequency control, this circuit can realize wide-range output voltage regulation (45-700 V), solve narrow output voltage of PWM control, reduce switch frequency variety and ripple of output voltage. Practical performance demonstrates its efficiency and advantages.