基于改进PR控制器的新能源并网检测平台设计

提出一种新能源并网检测平台,用于并网逆变器的性能检测。该平台采用背靠背式PWM变换器的电路拓扑结构,整流器采用基于LC滤波的三相整流器,逆变器采用三个H桥逆变器,分别发生三相电压。检测平台采用电压电流双环控制策略,能够模拟电网电压幅值跌落、三相不平衡、电压谐波及频率偏差等电能质量实际运行情况。为提高输出电压稳态精度,提出一种基波和谐波分开控制的改进的PR控制器,应用于逆变器的控制系统,通过极点配置的方式进行控制参数设计。实验验证了该方法的有效性和可行性。

Parameter design of testing platform for new energy grid connected devices based on improved PR controller

In order to test the performance of grid-connected inverters, a testing platform is proposed, which takes back to back PWM converter as its circuit topology. The rectifier side adopts a three-phase voltage LC rectifier and the inverter side takes three single-phase H-bridge inverters to output three-phase voltage separately. The testing platform can simulate various power quality conditions such as voltage sags, three-phase imbalance, voltage harmonics and frequency offset, etc. To improve the dynamic response, voltage and current double-loop control strategy is adopted. A modified PR controller is proposed to improve the control static accuracy. The control parameters are designed through pole assignment method. The validity and feasibility of the proposed method is demonstrated via experimental results.