摘要
分析了采用比较器、运算放大器、RS触发器等分立元件和基于SG3525电压调节芯片控制PWM Buck三电平变换器的两种控制方式的原理.采用分立元件的控制方法虽然成本较低,但因参数不可能完全匹配,容易出现三电平波形不对称的问题;基于SG3525电压调节芯片的控制方法可用集成芯片代替分立元件,大大简化了电路,能较好地解决电路的不均压问题.通过分析,验证了采用上述两种控制方法对实现输入电压为120 V(90～180 V),输出为48 V/4 A,开关频率为50 kHz的PWM Buck三电平变换器的控制是行之有效的.根据实验结果对两种控制方法进行了比较.
This paper analysis two control methods:both discrete devices (such as comparator,operational amplifier,RS flip-flop etc.) and voltage modulator based on SG3525 chip in PWM Buck three-level (TL) converter.Although the PWM Buck TL converter implementation with discrete devices costs less,yet it is impossible to match parameters wholly which easily make TL waveform asymmetry.Otherwise the voltage modulator based on SG3525 chip replaces many discrete devices, so the circuit is simplified,voltage-sharing problem is easily solved. In addition, PWM Buck TL converters based on previous two control methods are verified by experiment under the conditions of normal input voltage 120 V, output voltage 48 V, output current 4 A, switching frequency 50 kHz. A comparison between two control method is carried out on the basis of experment results,and a conclusion is got that the mentioned control methods are availble.
出处
《电力电子技术》
CSCD
北大核心
2004年第4期83-85,共3页
Power Electronics
