基于混合控制策略的光伏电池模拟器

摘要

根据光伏电池输出特性数学模型，对光伏电池模拟器的动态调节过程进行了详细理论分析，指出由于光伏电池的电流．电压输出具有非线性特性，单纯的输出电压控制或输出电流控制难以实现对光伏电池输出特性的全段模拟。由此提出一种光伏电池模拟器的混合控制策略，将光伏电池输出特性划分为三部分，基于TMS320LF2407DSP控制单元完成采样、计算和PWM输出，实现对光伏电池模拟器输出的电流电压混合控制。文章最后通过一个2kW的光伏电池模拟器样机，实现了对光伏电池阵列在不同光强、温度和负荷下的输出特性的模拟，通过分别连接并网逆变器和可变电阻性负载的测试，表明了该混合控制策略的有效性及良好的动态性能。%Based on the output characteristics of the photovoltaic (PV) cells, this paper analyzes the dynamic control process of PV simulator theoretically. Due to concluding that due to the nonlinear output characteristics, and it is difficult to simulate the whole PV I-U output curve by simply using pure voltage control or current control methods. Therefore a hybrid control strategy for the PV simulator is presented. By dividing the PV output curve into three segments, the proposed strategy implements hybrid current or voltage control via sampling, calculation and PWM output using a TMS320LF2407 DSP based control unit. A 2kW PV simulator prototype was built up in the lab, which could simulate the PV output characteristics under different irradiation, temperature and loads. The effectiveness and dynamic performance of the proposed hybrid control strategy was validated by tests using a grid-connected inverter and a variable resistive load respectively.