中文摘要：

为了充分发挥直流微网中储能系统的作用,提出一种适用于直流分布式储能系统的基于储能单元剩余容量（stateof charge,SOC）的改进下垂控制方法。利用该方法可以实现负荷功率在不同储能单元之间的动态分配。该方法中设置传统下垂控制中的下垂系数和储能单元SOC的n次幂呈反比。通过改变SOC的幂指数n,可以实现对SOC及输出功率均衡速率的调整。由于该控制方法基于下垂控制实现,因此会带来直流母线电压跌落。该文引入二次控制方法,以提升母线电压至其额定取值。传统的二次控制针对固定系数的下垂控制进行母线电压跌落补偿,而在改进的下垂控制方法中,下垂系数根据SOC改变,以扰动的形式作用于二次控制系统。该文验证了二次控制对于改进下垂控制方法的适用性,建立了控制结构的整体模型,并根据该模型对控制系统的稳定性进行了验证。利用Matlab/Simulink进行了仿真验证,并搭建了基于dSPACE1103的2×2.2 kW样机平台,对所提出的控制结构进行了实验验证。

英文摘要：

In order to take advantage of the dispersed energy storage units in the DC micro-grids, an improved state of charge （SOC） based droop control method for energy storage systems was proposed in this paper. Dynamic load power sharing among different energy storage units was achieved by using this method. Specifically, the coefficient in the conventional droop control method was set to be inversely proportional to the nth order of SOC. The speed of SOC and output power equalization can be adjusted by changing the exponent n of SOC. Since the above method was realized based on droop control, the deviation in the DC bus voltage was involved. Secondary control method was employed in this paper in order to restore the bus voltage to its reference value. The conventional secondary control was used for the droop control method with constant droop coefficient. In the above improved droop control method, the droop coefficient was changed by the SOC. It acted upon secondary control as a disturbance. In this paper, the feasibility of secondary control for the SOC-based droop control method was tested. The model of the overall control system was obtained and the system stability was thereby studied based on it. Simulation validation was realized by Matlab/Simulink and a 2-2.2 kW prototype based on dSPACEll03 was implemented for the experimental demonstration.