Electric vehicle charging piles belong to the distribution network side, and their communication methods are often considered together with distribution network automation. Communication is a key point and difficulty in distribution network automation. Different areas and different conditions, and applicable communication methods are different. Specific to electric vehicle charging piles, the communication methods mainly include wired mode and wireless mode:

(1) Wired mode

The wired methods mainly include: wired Ethernet (RJ45 line, optical fiber), industrial serial bus (RS485, RS232, CAN bus).

The main advantages of wired Ethernet are reliable data transmission and large network capacity. The disadvantages are complicated wiring, poor scalability, high construction cost and poor flexibility.

The advantages of industrial serial bus (RS485, RS232, CAN bus) are reliable data transmission and simple design. The disadvantages are complicated layout, poor expandability, high construction cost, poor flexibility and low communication capacity.

(2) Wireless mode

The wireless mode mainly uses mobile data access services of mobile operators, such as: GRPS, EVDO, CDMA, and the like.

The mobile data service using the mobile operator needs to connect the electric vehicle charging pile, which is the internal equipment of the grid, to the mobile operator's mobile data network, and needs to pay an expensive monthly rent and annual fee. As the number of charging piles increases, the cost will become more and more. The greater the data security and the reliability of the network are restricted by the mobile operator, which is not conducive to the safe operation of the device. Secondly, the mobile operator's mobile access bandwidth is shared bandwidth, when there are a large number of devices in the local area. When the reliability of access and the average bandwidth of each user are deteriorated, it is not conducive to dense access of the charging pile group and data transmission of large data volume.