Design standard for charging piles in underground garages

The design standards for underground garage charging piles should be combined with the construction scale of the underground garage to determine the power supply and distribution system design, load calculation, and power distribution charging monitoring system design of the underground garage electric vehicle charging piles. The requirements generally include:

1. General design requirements for charging piles in underground garages
1. There are 3 kinds of commonly used charging piles:
(1) AC Charging Pile, the power supply adopts 220V AC voltage;
(2) DC Charging Pile, the power supply adopts 380V AC voltage;
(3) AC and DC integrated charging pile, the power supply adopts 380V AC voltage.
(Note: local requirements shall prevail when there are special requirements in the region)
2. The charging pile shall have functions such as leakage protection, over-under-current, over-under-voltage, and over-temperature protection.
3. The charging pile shall have an emergency shutdown function, and the charging gun shall have a protection function for plugging and unplugging. Lightning protection measures should be taken for charging piles installed outdoors. The charging pile should have an automatic wire-rewinding function to prevent damage to the charging cable caused by improper use.
4. The selected charging pile should meet the relevant requirements of the national standards, energy industry standards and the State Grid Corporation corporate standards to meet the charging needs of different models. The charging pile should be compatible with the charging function of the new/old national standard electric vehicle.
5. Special electric vehicles need to set up special charging piles, and the owner shall apply to the property and relevant departments for implementation.

2. Underground garage charging pile power supply and distribution and low voltage system
1. For newly-built residential parking garages (yards), when designing the power capacity of substations, the load capacity of electric vehicle charging piles should be fully considered, and low-voltage power distribution circuits should be reserved or special transformers and power distribution systems should be reserved. .
2. The load calculation of electric vehicle charging piles should be calculated according to the unit index method according to the number of electric vehicle parking spaces in the plan design stage.
3. The load calculation of electric vehicle charging piles should be carried out according to the specific parameters of the charging piles using the demand coefficient method, and the value of the demand coefficient should meet the relevant requirements of national and local standards.
4. The power distribution power supply of electric vehicle charging piles should be provided with a dedicated loop for power supply. The power supply loop of the charging pile should be connected to the residential public transformer power distribution system or non-residential supporting special transformer power distribution system according to the requirements of the local power supply bureau.
5. Electric vehicle charging piles should adopt radial power distribution, and the power distribution system should achieve three-phase load balance.
6. Suppressive measures should be taken to limit the harmonics of the charging pile power distribution system within the specified range.
7. The wires (cables) and conduits of the power distribution lines of charging piles should be selected according to the most economical principle, provided that they meet national and local standards. The specifications of wires (cables) should not be arbitrarily increased, and the material standards and specifications of conduits should not be arbitrarily increased.
8. The illuminance value of the electric vehicle parking space area should meet the relevant requirements of national and local standards.

Three, underground garage charging pile metering, monitoring and communication system
1. The charging pile should be equipped with a metering electric energy meter, and the number of electric energy meters should meet the requirement of "one meter per pile". The power distribution box for charging piles should be arranged in a reasonable location according to the parking area of electric vehicles divided by the building.
2. The charging pile is equipped with IC card reading device or code scanning function to realize charging control and charging billing functions. The charging standards for charging piles shall be implemented in accordance with the requirements of the local power supply bureau. Charging piles should have multiple settlement methods.
3. The charging pile should be equipped with an Ethernet communication interface or a wireless communication module as required to facilitate the later network management of the charging pile and the system networking with related management departments.
4. Electric Vehicle Charging Pile monitoring and communication system should be set up according to actual needs of the project. The monitoring system should monitor and control the power supply status, power quality, and operation status of power supply equipment. The communication system should be able to communicate with the superior monitoring and management system, accepting instructions from the superior monitoring and management system, and uploading data to the superior monitoring and management system.
5. The control room of the charging pile monitoring and communication system is incorporated into the property management comprehensive information platform, and no separate control room is set up.
6. According to the project product portfolio (high-rise, small high-rise, multi-storey), carry out technical and economic comparison of water supply schemes, and the descending order of cost is: frequency conversion pressure control system with water tank, direct connection water supply system without negative pressure pipe network, municipal pressure Direct supply, multi-scheme combination can be selected depending on the project situation.