A Double Layer Laxity-Based Approach to Queue Management for Multipart EV Charging

With the increasing penetration of plug-in electric vehicles (PEV s), the availability of public PEV charging stations (PEVCS) becomes a major concern. Indeed, in a PEVCS with a limited number of chargers, the waiting time may be quite large, particularly during peak hours, given that each PEV requires a considerable amount of time to charge. This could lead to discontent with the service and a high customer attrition rate. In this paper, we propose a portable multi-port system (PMS), which is a patent-protected technology, that optimises the investment cost of the charging station while improving the accessibility of the chargers. The system allows multiple vehicles to be connected to the same charger and be automatically charged according to an optimized scheduling scheme. To ensure greater accessibility, a double layer laxity-based approach (DLBA) has been designed to assign the most appropriate charging spot for each vehicle according to their charging urgency. The proposed solution is shown to outperform the single layer laxity-based allocation method in terms of the required number of chargers meeting PEVs charging needs.