一种可抑制共模电流的三相Sepic电流源逆变器

THREE-PHASE SEPIC-TYPE CURRENT SOURCE INVERTER THAT CAN SUPPRESS COMMON MODE CURRENT

该文将Sepic电路和传统电流源逆变器结合,提出一种新型可升降压的三相电流源逆变器,并通过构建直流旁路,实现对共模电流的抑制。所提出的新型逆变器拓扑具有能实现升降压、调制方式简单且易于实现等优点,可适用于直流电压范围变化较大的光伏发电等场合。该文首先介绍了三相Sepic电流源逆变器电路拓扑的构造方法和工作原理;其次,推导了逆变器在任意开关时刻的共模电压表达式,并对其共模电流抑制效果进行分析;然后,建立逆变器的等效电路图和数学模型,详细分析逆变器的升降压能力;最后,通过仿真和实验证明所提出的三相Sepic电流源逆变器及其控制方案的有效性和可行性。

In this paper,a novel three-phase current source inverter with single-stage Buck-Boost function is proposed by combining Sepic circuit with traditional current source inverter,and the common mode current of the inverter is suppressed by constructing the DCbypass.The proposed inverter topology has the advantages of the ability to realize boosting and bucking,simple and easy to implement modulation,which can be applied to the occasions where the DC voltage range changes greatly like photovoltaic power generation.This paper firstly introduces the circuit topology and working principle of the three-phase Sepic-type current source inverter.Secondly,the expression of the common mode voltage of the inverter at any switching time is deduced,and its common mode current suppression effect is analyzed.Thirdly,the equivalent circuit diagram and mathematical model of the inverter are established,and the Bbuck-Boost capability of the inverter is analyzed in detail.Finally,the effectiveness and feasibility of the proposed three-phase Sepic-type current source inverter and its control scheme are proved by simulations and experiments.