级联多电平准Z源逆变器的无差拍并网控制策略

以单项级联准Z源逆变器为研究对象,以提高动态响应速度和减小并网电流总谐波畸变率为研究目标,提出一种总分式无差拍并网控制策略。首先,针对级联型准Z源逆变器各模块输入功率有差异的特点,定义模块功率比例因子并将其应用于模块功率控制,实现各模块差异化功率分配和最大功率输出,并实现各模块直流链电压平衡。其次,建立并网电流与系统反馈状态量模型,采用无差拍控制策略实现并网电流快速控制。最后,通过建立仿真模型验证了所提算法的有效性和正确性。

Deadbeat grid-connected control strategy of quasi-Z-source cascaded multilevel inverter

In order to improve the dynamic response speed and reduce the total harmonic distortion of grid-connected current of the single-phase quasi-Z-Source Cascaded Multilevel Inverter (qZS-CMI), a total fraction deadbeat grid-connected control strategy is proposed. Firstly, for the difference of input power of each module of the cascaded quasi-Z source inverter, the module power scaling factor is defined and applied to the module power control to realize the module differentiated power distribution and maximum power output, and realize DC-link voltage balance of each module. Secondly, the grid-connected current and system feedback state quantity model is established, the deadbeat control strategy is used to realize the grid-connected current fast control. Finally, the effectiveness and correctness of the proposed algorithm are verified by the simulation model. This work is supported by National Natural Science Foundation of China (No. 51707126).