基于态势感知的高渗透率电动汽车接入电网后电压调整策略

Voltage Adjustment Strategy for High-Penetration Electric Vehicles Connected to Power Grid Based on Situation Awareness

随着电动汽车使用量增加,区域配电网在高渗透率电动汽车接入配电网后会出现节点电压越限问题。基于态势感知技术,提出区域配电网内无功补偿设备以及电动汽车充电站联合参与的电压调整策略,通过构建二级调压模式确保配电网的电压状态。首先,在态势觉察阶段收集电动汽车状态、电网运行状态以及电动汽车充电站状态等信息;其次在态势理解阶段利用态势觉察阶段收集到的信息进行高渗透率电动汽车接入电网后模拟构建综合成本最小目标函数;然后在态势预测阶段根据电动汽车充电需求、电动汽车充电站信息预测高渗透率电动汽车接入电网后配电网电压偏差,基于潮流断面建立全局电气距离矩阵对预测电压修正,确认电网预测电压偏差;最后在利导阶段引入配电网电压偏差指标确定配电网电压偏离程度同时考虑配电网调压方式,对于不同程度的电压偏差确定配电网二级调压控制策略。通过IEEE 30节点系统进行仿真分析,验证了所提方法能够有效解决高渗透率电动汽车接入电网后电网电压越限问题。

Along with the increase of EVs use,the regional distribution network will experience nodal voltage overlimit problem after high penetration EVs are connected to the distribution network.Based on situation awareness technology,this paper proposes a voltage adjustment strategy with the joint participation of reactive power compensation equipment and EVs in the regional distribution network to ensure the voltage status of the distribution network through constructing a secondary voltage regulation mode.In the situation perception stage,the information on the EV status,grid operation status and EV charging station status is collected;in the situation assessment stage,the information collected in the situation perception stage is used to establish an objective function with minimum comprehensive cost after high penetration EVs are connected to the grid;in the situation prediction stage,the voltage deviation of the distribution network is predicted according to the charging demand of EVs and the information of EV charging stations,and a global electrical distance matrix is established to correct the predicted voltage based on the power flow section and to confirm the voltage deviation of the grid;in the facilitation stage,the distribution network voltage deviation index is introduced to determine the degree of distribution network’s voltage deviation with consideration of the voltage regulation mode within the distribution network,and the secondary voltage regulation control strategy of the distribution network is determined for different degrees of voltage deviation.A simulation analysis is carried out with IEEE 30-node system,and the results have verified that the proposed method can effectively solve the grid voltage overlimit problem after high penetration of EVs are connected to the grid.