基于虚拟谐波阻抗的微电网谐波抑制控制策略

Control strategy of harmonic suppression of micro-grid based on virtual harmonic impedance

针对微电网中接入非线性负载带来的谐波污染问题,提出了基于虚拟谐波阻抗的微电网谐波抑制控制策略。分析了下垂控制原理,给出了2台逆变器并联运行的谐波抑制模型;采用基于二阶广义积分模型的方法检测谐波电流,并采用基于二阶广义积分模型改进的PR准比例谐振控制器实现了电压零稳态误差控制;分析了虚拟谐波阻抗控制策略及其实现。仿真和实验结果验证了该控制策略的正确性和可靠性。

In view of problem of harmonic pollution caused by nonlinear loads in micro-grid, a control strategy of harmonic suppression of micro-grid based on virtual harmonic impedance was proposed. The principle of droop control is analyzed, and harmonic suppression model of two inverters running in parallel is given. The harmonic current is detected by SOGI model and voltage zero steady state error control is achieved by improved PR quasi-proportional resonant controller based on SOGI model. The virtual harmonic impedance control strategy and its implementation are analyzed. The simulation and experimental results verify correctness and reliability of the control strategy