Research On POF-CAN Based Monitoring System For Electric Vehicle Charging Station

Charging piles are important energy service infrastructures providing power supply for electric vehicles.To realize the digital and centralized management of charging piles,charging piles monitoring systems play important roles.Geographical distribution of charging piles has the characteristics of widespread,extensive and scattered.In addition,electromagnetic interference generated by high-power conversion equipments in charging station may influence the communication system.It's necessary to conduct a study of monitoring system fot charging stations comprehensively considering reliability,economy and flexibility of the scheme.In this paper,a POF-CAN based monitoring system for charging piles/stations is proposed.Plastic Optical Fibre(POF),which has characteristics of anti-interference,flexibility and economy,is selected as transmission medium of the system,combined with Controller Area Network(CAN),which is multi-host,efficient and easy to expand.The overall system is devided into a three-layer architecture to implement,which is of equipment/acquisition layer,POF-CAN communication layer and station control layer.In POF-CAN communication layer,the logic control interface circuit of POF-CAN ring network communication with fuction of bus arbitration and anti-self-locking is designed,according to the specification of CAN protocol physical layer and link layer,as well as the communication characteristics of POF ring net.Moreover,an application layer protocol is proposed according to the characteristics of message information interaction in EV charging station monitoring system.In equipment/acquisition layer,monitoring node with functions of IC card interaction,real-time power collection and charging pile control is implemented based on STM32.In station control layer,the upper computer with real-time monitoring,database and visualization function is programed based on LabVIEW.Simulation tests were carried out in the laboratory environment to verify the feasibility and effectiveness of the design.The POF-CAN baed monitoring system proposed in this paper based on all-optical link.Compared with the monitoring system of wireless communication,it has better security and strong anti-electromagnetic interference ability.In comparison with traditional communication media such as quartz fiber and twisted pair,it is more flexible and easy to install and maintain.This paper provides a new optional scheme for monitoring system of EV charging station.Through further technical improvement and improvement,there will be great market potential and application prospects.