According to the U.S. Department of Transportation (DOT), there are approximately 47,000 charging outlets for plug-in electric vehicles (EVs) and hybrid automobiles in the United States, excluding private stations. The implementation of these charging networks has been induced by the growth of electric vehicles and the advancement of their technology during the earlier years of our current decade. In fact, it has been estimated that plug-in EVs might be disruptive to gasoline demand by 2031.
Charging stations are integral to the success of EVs, products that have long been hindered by the influence of a phenomenon known as “range anxiety”. This refers to the fear that electric vehicles that might be ineffective in reaching their destinations, a belief that is fueled by the relatively limited miles per charge of most current EVs on the market. The easiest way for EV owners to recharge their vehicles is through home chargers, generally for overnight use. However, with a growing number of charging stations, “refueling” has become simpler throughout the day.
Types of EV Charging Stations
The commonly used electric vehicle chargers are referred to as level 1 and level 2 chargers, and they provide AC electricity to the automobile via onboard charging. Alternatively, there are now DC fast chargers (also known as level 3 or level 4 chargers), which bypass the onboard charger and provide DC electricity to the car’s battery via a special charging port. DC chargers, due to this capability, are able to charge EV batteries far quicker than AC chargers, but they are limited to few electric automobiles and cost considerably more.
As EV charging system technology progresses, standards maintain their importance, as standardized practices can not only assure safe, reliable, and efficient charging of automobiles but can also be used to guarantee similarities among different charging stations, something that is surely advantageous for an EV driver who frequently travels and requires their automobile to be widely compatible with charging stations. The standards for AC and DC electric vehicle conductive charging systems are within the IEC 61851 series. These documents specify the general characteristics and conditions of the EV supply equipment and its connection to the car, along with the digital communication between the station and the automobile.
EV Conductive Charging System Standards (IEC 61851)
IEC 61851-1 Ed. 3.0 b:2017 – Electric vehicle conductive charging system – Part 1: General requirements covers the characteristics and operating conditions of EV supply equipment, the specification of the connection between the supply equipment and the EV, and the guidelines for electrical safety for the supply equipment. This standard is intended to serve as the basis for all subsequent standards in the IEC 61851 series. It is applicable to supply equipment for charging electric road vehicles with a rated supply voltage up to 1,000 V AC or up to 1,500 V DC and a rated output voltage up to 1,000 V AC or up to 1,500 V DC.
IEC 61851-23 Ed. 1.0 b:2014 – Electric vehicle conductive charging system – Part 23: DC electric vehicle charging station builds off the information from IEC 61851-1 Ed. 3.0 b:2017 to give the guidelines for DC EV charging stations (DC charger) for conductive connection to the vehicle.
This standard has a corrigendum: IEC 61851-23 Ed. 1.0 b cor.1:2016
IEC 61851-24 Ed. 1.0 b:2014 – Electric vehicle conductive charging system – Part 24: Digital communication between a d.c. EV charging station and an electric vehicle for control of d.c. charging applies to digital communication between a DC EV charging station and an electric road vehicle for control of DC charging. It allows the user to make use of one of two communication architectures, based on either CAN protocol or Homeplug Green PHY™.
This standard also has a corrigendum: IEC 61851-24 Ed. 1.0 b cor.1:2015
In addition, many standards in the IEC 61851 series are currently in development. These documents are to be within the Part 3 and Part 21 subseries, and are as follows:
- Part 21-14: Electric vehicle onboard charger EMC requirements for conductive connection to an AC/DC supply. This part will cover requirements for EMC onboard the vehicle.
- Part 21-25: EMC requirements for OFF board electric vehicle charging systems. This part will cover all requirements for AC and DC EV supply equipment. EMC requirements for wireless power transfer systems (WPT) will not be included.
- Part 3-1: Electric vehicles conductive power supply system – Part 3-1: General Requirements for Light Electric Vehicles (LEV) AC and DC conductive power supply systems.
- Part 3-2: Electric vehicles conductive power supply system – Part 3-2: Requirements for Light Electric Vehicles (LEV) DC off-board conductive power supply systems.
- Part 3-3: Electric vehicles conductive power supply system – Part 3-3: Requirements for Light Electric Vehicles (LEV) battery swap systems.
- Part 3-4: Electric vehicles conductive power supply system – Part 3-4: Requirements for Light Electric Vehicles (LEV) communication.
- Part 3-5: Electric vehicles conductive power supply system – Part 3-5: Requirements for Light Electric Vehicles communication – Pre-defined communication parameters.
- Part 3-6: Electric vehicles conductive power supply system – Part 3-6: Requirements for Light Electric Vehicles communication –Voltage converter unit.
- Part 3-7: Electric vehicles conductive power supply system – Part 3-7: Requirements for Light Electric Vehicles communication – Battery system.