基于三相单级式光伏并网发电系统的电路拓扑结构,提出了一种快速逼近插值算法实现光伏发电的最大功率跟踪(maximum power point tracking,MPPT),光伏并网采用电压外环和电流内环双闭环控制,通过同步旋转坐标变换结合逆变器的控制,利用比例积分控制实现无功功率与有功功率的独立解耦控制。MATLAB系统仿真结果表明,该方法能够快速稳定地实现单位功率因数最大功率并网,降低并网系统成本,提高光伏并网的电能质量。
英文摘要:
According to the structure diagram of three-phase photovoltaic (PV) grid power generation system and double closed-loop grid-connection control strategy, a fast approximation interpolation algorithm to achieve maximum power tracking (maximum power point tracking, MPPT) function is proposed. The PV grid inverter circuit topology and control structure are analyzed, with the control structure using synchronous rotating coordinates based on PI control, the voltage loop and current inner ring double closed loop control, the active power and reactive power decoupling control is realized. The simulation results based on MATLAB has shown that this method can achieve flexible grid connection with unit power factor easily, and can reduce the cost and is easy to realize.