基于PR控制的三相光伏发电并网逆变器研究

摘要

In the process of PV Grid, in order not to affect the quality of the grid, must ensure that the output current of photovoltaic power generation system and grid voltage maintain a high degree of consistency in the frequency , phase and amplitude. In order to make the output current of PV Grid inverter to meet the relevant standard of the grid, the appropriate grid filter and control strategy are the key. In order to improve the quality of the grid current and reduce the pollution of the grid harmonic current on the grid, the three-phase full-bridge inverter circuit with LCL filter is selected. In the grid control strategy, select the double loop current control based on grid current and capacitance current, and introduce the PR control into the double loop control system,analyze that PR control can achieve zero steady state error tracking of grid sinusoidal reference current and anti-grid voltage disturbances. Double loop current control and SVPWM control combined is maken, and proved the stability of this method through the simulation experiment%在光伏发电并网过程中,为了不影响电网的质量,必须保证光伏发电系统的输出电流与电网电压在频率、相位和幅值上保持高度一致.为了使光伏并网逆变器输出的并网电流满足相关的并网标准,选择合适的并网滤波器以及并网控制策略是关键.为了提高并网电流的质量,减少并网谐波电流对电网的污染,选择带LCL滤波器的三相全桥逆变电路.在并网控制策略上选择基于并网电流和电容电流的双环电流控制,将PR控制引入到双环控制系统中,从理论上分析了PR控制能实现对并网正弦参考电流的零稳态误差跟踪和抗电网电压干扰.将双环电流控制和SVPWM相结合,通过仿真实验证实了系统的稳定性.