基于扩散算法的无下垂分布式储能控制

Droop-Free Distributed Energy Storage Control Based on Diffusion Algorithm

针对线路阻抗不匹配及母线电压不一致时,下垂控制无法同时实现母线电压稳定及储能间功率精确分配的问题,提出一种基于扩散算法的无下垂分布式储能控制策略.首先,将扩散算法应用于直流微电网的分布式估计中获取全局平均量,同时将电压额定值与平均电压的差值作为补偿项,用于恢复母线电压偏差.为了实现不同额定容量及不同荷电状态(SOC)的储能间功率精确分配,设计储能的标准功率并将其与平均标准功率的差值作为补偿项,用于储能间SOC的均衡.最后,利用RT-LAB平台搭建模型,分别验证4种不同工作模式下所设计控制策略的有效性.实验结果表明,所提控制策略可实现孤岛直流微电网母线电压恢复及储能功率的精确分配.

A droop-free distributed energy storage control strategy based on the diffusion algorithm is proposed to address the inability of droop control to simultaneously achieve bus voltage stability and accurate power distribution among energy storage systems when the line impedance is mismatched and bus voltage is inconsistent.First,the diffusion algorithm is applied to the distributed estimation of direct current(DC)microgrid to obtain the global average,and the difference between the voltage rating and the average voltage is used as a compensation term to restore the bus voltage deviation.Then,in order to achieve the accurate distribution of power between energy storage systems with different rated capacities and different states of charge(SOC),a standard power of energy storage is designed and the difference between the standard power and the average standard power is used as a compensation term for the equilibrium of SOC between energy storage systems.Finally,a model based on RT-LAB is built to verify the effectiveness of the designed control strategy in four different operating modes.The experimental results show that the proposed control strategy can achieve the bus voltage recovery and the accurate distribution of energy storage power in the isolated DC microgrid.