考虑通信异常的直流微电网储能单元分布式协调控制研究

由于分布式新能源接入的波动性，需要针对孤岛直流微电网配置一定容量的储能设备。为了防止分布式储能单元的过度放电或深度充电，必须保证储能单元充放电过程中荷电状态(state of charge, SOC)均衡。针对该问题，提出了一种考虑通信异常的储能单元分布式控制策略。针对不同额定容量的储能单元，对传统下垂控制进行改进，利用采样保持器周期性修改下垂系数，直至储能单元SOC均衡。并利用电压和电流信息生成单一的补偿环实现输出电流按额定容量的比例分配和直流母线电压补偿，降低系统通信能力要求。若通信发生故障，通过Dijkstra算法更新拓扑结构矩阵，基于改进后的动态一致性算法获取相邻节点的信息，得到新通信拓扑结构下的信息平均值；并通过频域分析证明系统的稳定性。最后，在RTLAB平台中搭建4种案例模型，验证所提控制策略的有效性。

Distributed coordinated control of a DC microgrid energy storage unit considering abnormal communication

Because of the volatility of accessing distributed new energy, it is necessary to configure energy storage equipment with a certain capacity for an isolated DC microgrid. To prevent excessive discharge or deep charging of distributed energy storage units, it is necessary to ensure that the state of charge (SOC) of the energy storage units is balanced during charging and discharging. To achieve this, a distributed control strategy of an energy storage unit considering communication anomaly is proposed. For energy storage units with different rated capacities, the traditional droop control is improved, and the droop coefficient is periodically modified using a sample holder until the SOC of the energy storage unit is balanced. Using the voltage and current information to generate a single compensation loop, the output current is distributed in proportion to the rated capacity and the DC bus voltage is compensated, reducing the requirements of the system communication capability. In the case of communication failure, the Dijkstra algorithm is used to update the topology matrix, and the information of adjacent nodes is obtained based on the improved dynamic consistency algorithm to obtain the average value of information under the new communication topology. The stability of the system is verified by frequency domain analysis. Finally, four case study models are built in the RTLAB platform to verify the effectiveness of the proposed control strategy.