基于电流无差拍和PI复合控制的新能源并网技术

Research on New Energy Grid Based on Current Deadbeat and PI Control

为了提高新能源整个并网系统的性能,在分析无差拍控制和PI控制的工作原理基础上,提出了基于电流无差拍和PI复合控制的PWM逆变的控制策略。通过Matlab/Simulink建模仿真三相并网系统,采用LCL滤波器滤波。当系统接三相对称纯阻性负载和整流性负载时,将系统逆变电压与电网电压、逆变电流与电网电压进行比较,以及对三相逆变电流进行谐波分析。仿真结果表明,该并网控制策略能较好地跟踪电网电压,波形畸变较小、动态响应快。

In order to improve the performance of the entire system, the paper proposes a grid-connected PWM inverter controlled by current deadbeat and PI algorithm. The simulation system with LCL filter is established by Matlab/Simulink. The inverter voltage and current are compared with the gird voltage and current respectively when the three-phase symmetrical load is connected to the system. The harmonic of the three-phase inverter current is also analyzed. The resistive load, rectified load and sudden load are connected to the system respectively. The results show that the combination of current deadbeat and PI algorithm is good in dynamic response and grid voltage tracking with small waveform distortion