一种可靠的滞环电流型双降压式半桥逆变电路

摘要

研究了一种新颖的双降压式半桥逆变电路(Dual buck half bridge inverter,DBI),该电路有无直通,效率高等特点.提出了一种DBI的无偏置电流运行方式和一种滞环电流型双降压式半桥逆变电路(Hysteresis current controlled dual buck half bridge inverter,HCDBI),消除了采用载波交截SPWM控制DBI正常工作所必需的偏置电流,进一步提高了效率.对HCDBI和传统半桥逆变器进行了理论上的损耗计算分析和实验验证,证明了HCBBI可大幅降低开关损耗,开关频率高,滤波器小.为实现逆变器的高频化提供了一种简洁的方法和新的途径.%A highly efficient and reliable topology-dual buck half bridge inverter (DBI) is introduced. The existence of discontinuous conduction mode (DCM) operation state requires the bias of inductor current for DBI implemented with linear controllers like ramp comparison SPWM (RCSPWM) controllers. A novel operation scheme for DBI and a hysteresis current controlled dual buck half bridge inverter (HCDBI) are proposed. The bias current required by RCSPWM DBI is eliminated and conduction losses are dramatically reduced. HCDBI has greatly improved the modulation performance in DCM region for the benefit of its excellent command tracking capability. The operational scheme and control strategy are presented. Power losses of the conventional half bridge inverter (CHBI) and HCDBI are compared with mathematical computation, and experimental verification is also executed. Both calculational and experimental results verify that HCDBI has a superior switching performance over CHBI. Its excellent high frequency operational capacity provides another access to realize high frequency operation of inverters.