[关键词]
[摘要]
Z源中点钳位式(NPC)三电平变换器把逆变和升压两种环节结合在一起,结构简单、工作效率高,但是针对这种结构输出的无功功率研究较少。提出了一种Z源NPC三电平变换器的恒功率并网控制策略。首先对这种变换器的结构及原理进行分析;再把恒功率控制引入到这种变换器的并网控制中,并采用空间矢量脉宽调制(SVPWM)实现了变换器的并网控制。MATLAB/Simulink软件仿真结果证明了这种变换器能够提高电压升压比。该控制策略可使变换器输出的有功功率、无功功率稳定于设定值,且并网电流谐波较低。
[Key word]
[Abstract]
Single stage Z-source three-level neutral point clamped (NPC) inverter combines voltage-boost and inversion functions, and it has the advantages of simple structure and high efficiency. A constant power grid-connected control method for Z-source NPC three-level inverter based on space vector pulse width modulation (SVPWM) was proposed. First, the structure and working principle of Z-source three-level NPC inverter was analyzed. Then, the constant power control strategy was introduced to Z-source three-level NPC inverter grid-connected system. Finally, simulation model of the system was built in MATLAB/Simulink software. The simulation results showed that Z-source NPC three-level inverter could boost the step-up ratio, this control method could make the output active and reactive power of the grid inverter track the set value effectively, and grid current harmonic content components were low.
[中图分类号]
[基金项目]
国家自然科学基金项目(61304134);上海市电站自动化技术重点实验室项目(13DZ2273800)