一种可抑制共模电压的H14三电平光伏逆变器

H14 three-level photovoltaic inverter for common-mode voltage suppression

为了减小共模电压对光伏系统的不利影响,文中提出了一种新型的三相逆变器拓扑(H14拓扑)及其控制方法,阐明了H14逆变器的工作原理,分析了H14逆变器各运行模式下各开关状态对应的共模电压,设计了基于开关函数的H14逆变器控制方式,实现了共模电压的有效抑制。对H14逆变器的共模电压、相电流、中点电位、线电压进行了分析,实验验证了所提拓扑结构及其控制方法对共模电压抑制的有效性。

For purpose of reducing the adverse effect of common mode voltage on photovoltaic system,a novel H14 three-level inverter topology and the corresponding control method for common-mode voltage(CMV)suppression are presented in this paper,and the working principle of H14 inverter is expounded.Operation status of the proposed H14 three-level inverter is analyzed under different switching patterns,and the corresponding CMV in each operation status is discussed.The control method of H14 inverter is presented based on the switching function,and the effective suppression of common mode voltage is realized.The operation performances of the proposed H14 inverter in terms of CMV,phase current,neutral-point potential,and line-to-line voltage are investigated.The HIL experimental verification results show that the proposed H14 three-level inverter can suppress the CMV effectively.