半周控制双Buck-Boost单级逆变器

摘要

本文提出了一种新颖的双Buck-Boost单级逆变器。单级式逆变器相比传统的两级式逆变器,拓扑结构大大简化,减小了体积重量,降低了损耗,在中小功率场合中的应用具有明显的优势。同时传统单级逆变器不能直接实现升压逆变,在输入母线电压较低时必须增加前级升压电路。针对以上情况,本文通过将两个Buck-Boost电路采用输入串联、输出并联的方式组合,得到一种新型的双Buck-Boost逆变器,并采用半周工作方式使其正常可靠工作,可实现单级直接升压逆变。文中对该电路的工作原理和控制策略进行了详细的分析。仿真和实验验证了新型电路的可行性。该电路在输入母线电压低于输出电压的宽电压范围内均能正常逆变,并取得了较好的波形质量和较高的变换效率。%A novel half load-cycle worked dual Buck-Boost single-stage inverter is presented in this paper.Compared with the traditional two-stage inverter,the single-stage inverter is smaller and lighter due to the structure is greatly simplified as well as the circuit components are reduced a lot.Direct boost DC-AC converter can not be realized by most traditional inverter,so one DC-DC converter has to be added in the front of traditional inverter when input bus voltage is low.In order to obtain one single-stage inverter which can make direct boost inverter come true,two Buck-Boost topologies are combined which are series-wound in input side and parallel connected in output side.Special half load-cycle control mode is used in this new inverter.No matter the input bus voltage is higher or lower than the output voltage,the new inverter works normally and reliably and the output waveform is good,the converter efficiency is high at the same time.Simulation and Experiment verifies those analysis.