Research On Electric Vehicle Charging Station Recommendation Based On Load Balancing

In recent years,with the improvement of charging technology,the penetration rate of electric vehicle(EV)in the automotive market has been increasing,and the demand for electricity has also increased dramatically.However,there exits differences in energy supply and demand and renewable energy distribution in different areas,resulting in unbalanced load distribution among Microgrids(MGs).Since EV charging behavior is uncertain,a mass of EV charging without coordination may coincide with the peak of the power grid,which will undoubtedly cause harm to the safe operation of the power system.The service capacity of charging stations,i.e.,the number of charging piles,has a non-negligible impact on EV charging behavior.The occupancy of charging piles determines that whether EVs can be charged immediately,and affects the load distribution in the multi-microgrid system.Therefore,this paper studies the impact of service capacity on load distribution in the multi-microgrid system and then modifies the load balancing matching strategy(LBMS).The main works of this paper are as follows:1)Considering the constraints of economic factors,the service capacity of charging stations is limited.In order to balance the load distribution among MGs,we adopt LBMS to guide EV charging behavior.The service capacity will also affect the staying time of EV in charging stations and then increase user average time.Therefore,we study the impact of service capacity on load distribution and user average time.We find that the larger the service capacity,the more balanced the load distribution,and the smaller the user average time.However,it is unrealistic to increase service capacity blindly.There exits the optimal service capacity in the multi-microgrid system.Once the service capacity is greater than that,increasing service capacity will not improve the system performance,but also cause the waste of charging facilities.2)LBMS only considered the load distribution among the multi-microgrid system at the time when EVs send charging request,but ignored the change of load distribution in the time period from sending charging request to finishing charging.Based on this,we propose a new charging station recommendation strategy,named improved load balancing matching strategy(ILBMS),which can dispatch EVs to appropriate charging stations.The simulation results show that compared with other strategies,ILBMS we propose can better optimize EV charging behavior,effectively balance the load distribution among MGs,and reduce the impact of a large number of EV charging behavior on the safe operation of the multi-microgrid system.Since we have emphasized the importance of service capacity,the impact of that on the load distribution under ILBMS is analyzed.The simulation results also show the superiority of ILBMS on the load balancing among MGs.