光伏模拟系统建模与控制器参数优化

摘要

At present, the PV simulator has some disadvantages, such as the output range of current and voltage is limited, the output ripple is large and parameter regulation needs a long time. In order to make the PV simulator have a better simulation result, this paper uses frequency response method to derive the controller parameters of the solar simulator. Firstly, this paper sets up the mathematical model of PV simulator and the controller model by the average state space method and obtains closed-loop system transfer function. Secondly, the frequency characteristic curve is used to optimize controller parameters. This method provides a theoretical basis for designing the PV controller. Using the Matlab simulation, it proves that the PI control parameters obtained by the frequency characteristics is more accurate than the parameters obtained by experience. At last, the experimental results show this method can effectively reduce the output ripple and expand the PV simulator's output scope. And when the load is low, it will make the PV simulator keep a better output.%针对目前光伏模拟器设计中存在的电压、电流输出范围小,纹波大,参数调节时间长等问题,提出了一个新的控制器设计方案.利用状态平均法,建立了光伏模拟器的数学模型和控制器模型,获得系统的闭环传递函数.再利用传递函数和波特图对控制器参数进行优化,为控制器的设计提供了理论依据.通过Matlab仿真,验证了用频率特性法得到的控制器参数比经验法获得的PI控制参数更加合理.在实验室内搭建硬件实验平台,实验结果证明用频率特性法进行参数设计,扩大了光伏模拟器的输出范围,减小了电流的输出纹波,使得在负载较低时,光伏模拟器仍可较好地模拟光伏特性曲线.