基于自适应下垂法的有功功率均分控制

Active power sharing control based on adaptive droop method

在低压孤岛微网中,受到线路阻抗不一致的影响,线路阻抗与并联逆变器的容量不匹配,传统下垂控制方法不能使并联逆变器有功功率达到均分的效果;并且传统下垂控制法反馈信号很难准确的测到线路阻抗后公共节点的电压。针对以上问题,提出了一种自适应的下垂控制方法,该方法具有可变的下垂系数和可变的空载电压,自动调节下垂系数和空载电压来减小并联逆变器有功功率分配的偏差和降低线路阻抗上的电压降。在负荷发生突变和扰动的情况下,利用MALATB2014a/SIMULINK软件平台分别对传统下垂控制和自适应下垂控制进行仿真实验验证,仿真结果验证了自适应下垂控制方法不仅可以使并联逆变器有功功率分配达到均分,还可以大大改善线路阻抗上的电压降。

In the low-voltage island micro-grid,the line impedance is not matched with the capacity of the parallel inverter due to the inconsistent line impedance. The traditional droop control method cannot make the effect of the parallel inverter active power to achieve equalization;it is difficult for the traditional droop control method feedback signal to accurately measure the voltage of the common node after the line impedance. Aiming at the above problems,an adaptive droop control method is proposed in this paper. The method has variable droop coefficient and variable no-load voltage,and automatically adjusts the droop coefficient and the no-load voltage to reduce the active power distribution of the parallel inverter,as well as reduce the voltage drop across the line impedance. In the case of load mutation and disturbance,the MATLAB2014 a/SIMULINK software platform is used to verify the traditional droop control and adaptive droop control. The simulation results verify that the adaptive droop control method can not only achieve the power equalization of the parallel inverter active power distribution,but also can greatly improve the voltage drop across the line impedance.