Z源风力发电并网无差拍控制策略

Deadbeat Control Strategy of Z-source Grid-connected Wind Power Generation

受风速变化的影响,系统功率、电流易受外界影响。为提高系统稳定性,通过分析Z源基本原理,提出基于Z源风力发电的无差拍电流内环控制策略。通过稳定Z源网络电容电压,实时调节直通占空比来调节风速的最大功率点跟踪。同时将虚拟磁链观测器运用到系统中,通过虚拟磁链计算得到电网电压相位,提高系统运行的可靠性。文中采用MATLAB/Simulink搭建系统仿真,仿真实验结果证实了控制策略的正确性,并网电流波形正弦性好,系统运行稳定,且能够实现单位功率因数运行。

Due to the change of wind speed change, system power and current are vulnerable to external factors. In order to improve the system stability, through the analysis of Z-source principle, deadbeat current inner-loop control strategy is established based on Z-source wind power generation. By stabilizing the Z-source capacitance voltage, shootthrough duty ratios are adjusted realtime to adjust the speed of maximum power point tracking （MPPT）. At the same time, virtual flux observer is applied to the system, with which grid voltage phase is calculated to improve the reliability of the system. The simulation is built in MATLAB/Simulink, and the simulation results verify the validity of the control strategy. The grid-connected current waveform is sine mostly. Moreover, the system runs stably, and it can realize unit power factor operation.