摘要
提出一种对称结构π型Buck-Boost交流变换器及其变结构控制策略。该变换器由Buck交流单元和Boost交流单元组成,与级联式两级电路相比,省去前级LC输出滤波器,简化了电路结构。根据前、后单元的工作与否,π型交流变换器存在4种工作模式:Buck模式、Boost模式、直通模式和Buck-Boost模式。通过等效改变电路结构,变结构控制策略使得π型Buck-Boost交流变换器只有3种工作模式:Buck模式、Boost模式和直通模式。π型Buck-Boost交流变换器虽然具有两个独立的控制对象、采用两级占空比调制,但实际上最多只有一级功率变换,且存在直接功率传递通路,适用于稳压或调压应用场合。
A novel π type Buck-Boost AC/AC converter with symmetrical structure and its variable structure control strategy are proposed.The converter comprises of a Buck alternating current cell and a Boost AC cell.Compared with cascaded Buck-Boost AC/AC converter,it has a simplified structure by canceling the LC output filter in the front stage.According to the working conditions of two cells,the π type Buck-Boost AC/AC converter has four kinds of operation modes:Buck mode,Boost mode,direct mode and Buck-Boost mode.By employing variable structure control strategy to change the circuit topology equivalently,it has only three kinds of operation modes:Buck mode,Boost mode and direct mode.So it at most bears one stage power conversion and possesses the direct pathway for power flow,though the π type AC/AC converter comprises of two independent control objects and employs two duty-cycle modulation.It is appropriate to applications of voltage stabilizing or regulating.
出处
《电力电子技术》
CSCD
北大核心
2012年第3期58-61,共4页
Power Electronics
关键词
变换器
变结构控制策略
工作模式
对称结构
converter
variable structure control strategy
operation mode
symmetrical structure