针对传统三电平逆变器光伏系统最大功率跟踪(maximum power point tracking,MPPT)响应速度慢、输出电流波形失真严重以及直流母线电压波动大的问题,提出了一种三相五电平中点箝位型(neutral point clamped,NPC)逆变器光伏并网系统。该...针对传统三电平逆变器光伏系统最大功率跟踪(maximum power point tracking,MPPT)响应速度慢、输出电流波形失真严重以及直流母线电压波动大的问题,提出了一种三相五电平中点箝位型(neutral point clamped,NPC)逆变器光伏并网系统。该系统采用模糊MPPT功率外环、直流电压中环以及电流内环的三环控制方案,实现了对最大功率的快速跟踪,降低了输出电流波形的总谐波畸变率(total harmonic distortion,THD),有效抑制了直流母线电压的波动。用MATLAB搭建模型,仿真结果证明了所提出的含五电平逆变器拓扑结构及其控制方法的有效性。展开更多
Multi-level inverters(MLIs)have become popular in different applications such as industrial power control systems and distributed generations.There are different forms of MLIs.The cascaded MLIs(CMLIs)have some special...Multi-level inverters(MLIs)have become popular in different applications such as industrial power control systems and distributed generations.There are different forms of MLIs.The cascaded MLIs(CMLIs)have some special advantages among them such as more different output voltage levels using the same number of components and higher power quality.In this paper,a 27-level inverter switching algorithm considering total harmonic distortion(THD)minimization is investigated.Switching angles of the inverter switches are achieved by minimizing a THD-based objective function.In order to minimize the THD-based objective function,the hyper-spherical search(HSS)algorithm,as a novel optimization algorithm,is improved and the results of improved HSS(IHSS)are compared with HSS algorithm and other five evolutionary algorithms to show the advantages of IHSS algorithm.展开更多
文摘针对传统三电平逆变器光伏系统最大功率跟踪(maximum power point tracking,MPPT)响应速度慢、输出电流波形失真严重以及直流母线电压波动大的问题,提出了一种三相五电平中点箝位型(neutral point clamped,NPC)逆变器光伏并网系统。该系统采用模糊MPPT功率外环、直流电压中环以及电流内环的三环控制方案,实现了对最大功率的快速跟踪,降低了输出电流波形的总谐波畸变率(total harmonic distortion,THD),有效抑制了直流母线电压的波动。用MATLAB搭建模型,仿真结果证明了所提出的含五电平逆变器拓扑结构及其控制方法的有效性。
文摘Multi-level inverters(MLIs)have become popular in different applications such as industrial power control systems and distributed generations.There are different forms of MLIs.The cascaded MLIs(CMLIs)have some special advantages among them such as more different output voltage levels using the same number of components and higher power quality.In this paper,a 27-level inverter switching algorithm considering total harmonic distortion(THD)minimization is investigated.Switching angles of the inverter switches are achieved by minimizing a THD-based objective function.In order to minimize the THD-based objective function,the hyper-spherical search(HSS)algorithm,as a novel optimization algorithm,is improved and the results of improved HSS(IHSS)are compared with HSS algorithm and other five evolutionary algorithms to show the advantages of IHSS algorithm.
