A detailed explanation of the world's foremost electric vehicle charging connector standards
Obviously, pure electric-based new energy vehicles have become the general trend in the automotive industry. However, under the current situation that it is difficult to make breakthroughs in battery technology in a short period of time, electric vehicles have widely deployed charging facilities, hoping to solve the worries of car owners through sufficient charging equipment. The electric vehicle charging connector, as a crucial component in the charging equipment, has faced direct conflict because of different standards in various countries. Here we sort out the world's various electric vehicle charging connector standards for you.
1. Combo
The Combo socket can allow slow charging and fast charging of electric vehicles. It is currently the most widely used socket type in Europe, including Audi, BMW, Chrysler, Daimler, Ford, GM, Porsche, and Volkswagen all equipped with SAE (Society of Automotive Engineers). ) developed charging interface.
On October 2, 2012, the revised draft of SAE J1772, which was voted by the relevant SAE committee members, became the only official DC charging standard in the world. The core of the average for DC fast charging based on the revision of J1772 is the Combo Connector.
The previous version of the standard (made in 2010) specified the basic J1772 connector for AC charging, with lower charging levels (AC Level1 for 120V and Level2 for 240V). This basic connector is widely used today and is compatible with Nissan Leaf, Chevrolet Volt, and Mitsubishi i-MiEV electric vehicles. In addition to all the original functions, the Combo Connector in the new J1772 standard formulated in 2012 has two more pins, which can be used for DC fast charging, but it is not compatible with the current production of old electric vehicles.
Pros: The most significant benefit of the Combo Connector is that in the future automakers can use a socket on their new models, not only for the first-generation, smaller-sized basic AC connector but also for the second-generation, larger-sized Combo Connector, the latter can provide both DC and AC currents, charging at two different speeds.
Disadvantages: Fast charging mode requires a charging station to provide up to 500 volts and 200 amps of current.
2. Tesla
Tesla cars have their own set of charging standards, claiming that they can run more than 300 kilometers in 30 minutes. Therefore, its charging socket has a maximum capacity of 120kw and a maximum current of 80A.
Currently, Tesla has 908 Supercharger stations in the United States. In order to enter China, Tesla has also established 7 supercharging stations in my country, 3 in Shanghai, 2 in Beijing, 1 in Hangzhou, and 1 in Shenzhen. In addition, in order to better integrate into various regions, Tesla plans to abandon the control of charging standards and adopt the national standards of various countries, which have been implemented in China.
Advantages: advanced technology, high charging efficiency.
Disadvantages: Contrary to the national standards of various countries, it is difficult to increase sales without compromise; the charging efficiency will be reduced after compromise, and it is a dilemma.
3. CCS
In order to change the status quo of chaotic charging interface standards, the eight major American and German manufacturers, Ford, GM, Chrysler, Audi, BMW, Mercedes-Benz, Volkswagen, and Porsche, released a "joint charging system" in 2012. "Combined Charging System" (Combined Charging System), the "CCS" standard.
The "joint charging system" can unify all existing charging interfaces, so that four modes of single-phase AC charging, fast three-phase AC charging, household DC charging and super-speed DC charging can be completed with one interface.
AE has selected the combined charging system as its standard, and in addition to SAE, the European Automobile Manufacturers Association (ACEA) has also announced that it has selected the combined charging system as the DC/AC charging interface for use in all plug-ins sold in Europe starting in 2017. Electric vehicle. Since Germany and China unified the charging standards for electric vehicles last year, China has also joined the European and American camps, bringing unprecedented opportunities for the development of electric vehicles in China. Zinoro 1E, Audi A3e-Tron, BAIC E150EV, BMW i3, Denza, Volkswagen e-up, Changan Yidong EV, and SmartEV all belong to the "CCS" standard camp.
Advantages: BMW, Daimler, and Volkswagen, the three German automakers, will increase their investment in electric vehicles in China, and the CCS standard may be more conducive to China.
Disadvantages: EVs that support the "CCS" standard are either sold in small numbers or are just starting to go on sale.
4. CHAdeMO
CHAdeMO is the abbreviation of CHArge de Move. It is a CHAdeMO socket supported by Nissan and Mitsubishi Motors in Japan. CHAdeMO translated from Japanese means "charging time is as short as a coffee break". This DC fast charging socket can provide a maximum charging capacity of 50kw.
EV models that support this charging standard include Nissan Leaf, Mitsubishi Outlander Plug-in Hybrid, Citroen C-ZERO, Peugeot iON, Citroen Berlingo, Peugeot Partner, Mitsubishi i-MiEV, Mitsubishi MINICAB-MiEV, Mitsubishi MINICAB-MiEV Truck, Honda Fit electric version, Mazda DEMIOEV, Subaru Stella plug-in hybrid, Nissan eEV200, etc. It should be noted here that Nissan Leaf and Mitsubishi i-MiEV electric vehicles have two different charging sockets, one of which is suitable for the basic J1772 connector, which is the Combo connector introduced in the first part; the other is suitable for Japan's native CHAdeMO standard connector.
The fast charging method adopted by CHAdeMO is shown in the figure, and the current is controlled by the CAN bus signal of the car. That is while monitoring the battery status, the current value required for charging is calculated in real-time, and a notification is sent to the charger through the communication line; the fast charger receives the current command from the car in time and provides the current according to the specified value.
Through the battery management system, the battery status is monitored and the current is controlled in real-time, which fully realizes all the functions required for fast and safe charging, ensuring that the charging is not limited by the universality of the battery. In Japan, 1,154 quick chargers installed according to the CHAdeMO standard have been put into use. In the United States, CHAdeMO's charging stations have also been widely "cast the net". The latest data from the US Department of Energy shows that there are 1,344 CHAdeMO AC fast charging stations in the United States.
Advantages: In addition to the data control line, CHAdeMO also uses the CAN bus as the communication interface. Due to its superior noise immunity and high error detection ability, the communication stability and reliability are high. Its good charging safety record has been affirmed by the industry.
Disadvantages: CHAdeMO was originally designed for a charging output of 100 kW, and the connector is very bulky, but the output power in the charging car is only 50 kW.
5. GB/T20234
In 2006, China issued the "General Requirements for Electric Vehicle Conductive Charging Plugs, Sockets, Vehicle Couplers, and Vehicle Jacks" (GB/T20234-2006). This national standard specifies the charging current as 16A, 32A, and 250A AC. The classification method of connection with 400A DC mainly draws on the standard proposed by the International Electrotechnical Commission (IEC) in 2003, but this standard does not specify the number of connection pins, physical size, and interface definition of the charging interface.
In 2011, China introduced the recommended standard GB/T20234-2011, which replaced some of the contents in GB/T20234-2006, which stipulated that the rated AC voltage should not exceed 690V, the frequency should be 50Hz, and the rated current should not exceed 250A; the DC rated voltage should not exceed 250A. Not more than 1000V, rated current not more than 400A.
Advantages: Compared with the 2006 version of the national standard, more charging interface parameters are calibrated in detail.
Disadvantage: The standard is still not perfect. In addition, it is only a recommended standard, and it is not enforced.
6. A new generation of ChaoJi charging system
In 2020, the China Electricity Council and the CHAdeMO Council will jointly launch the research work on the ChaoJi industrialization development route, and release the "Electric Vehicle ChaoJi Conductive Charging Technology White Paper" and the CHAdeMO3.0 standard respectively.
Chao Ji's charging system is forward and backward-compatible. New control and guidance circuit scheme are formulated, and a hard node signal design is added. When a fault occurs, the semaphore is used to quickly notify the opposite end to make a quick response in time to ensure charging safety. Establish a safety model of the entire system, optimize insulation monitoring performance, and clarify a series of safety issues such as I2t, y capacitance, PE conductor selection, maximum short-circuit capacity and PE disconnection. At the same time, the thermal management system is re-evaluated and designed, and a test method for the charging connection device is proposed.
Chao Ji charging interface adopts a 7-pin end face design, the voltage level can reach 1000 (1500) V, and the maximum current can reach 600A. The ChaoJi charging interface is designed to reduce the overall size, optimize the fit tolerance, reduce the size of the power terminal, and meet the IPXXB safety requirements. At the same time, the physical guide for plugging and unplugging is designed, which deepens the insertion depth of the front-end guide of the socket and meets ergonomic requirements.
Chao Ji charging system does not simply refer to a high-power charging interface, it is a set of systematic electric vehicle DC charging solutions, including control and steering circuit, communication protocol, design and compatibility of the connecting device, the safety of the charging system, high-power Thermal management under operating conditions, etc. Chao Ji's charging system is a unified solution for the world so that the same electric vehicle can be applied to the charging system of the corresponding country in different countries.
Summarize
Due to the differences in brands of new energy vehicles on the market today, the applicable charging equipment standards are not the same, and a single type of charging connector structure cannot meet all models. In addition, the technology in the field of new energy vehicles is still maturing. The charging piles and charging connection systems of many automobile manufacturers are still faced with unstable product design, potential safety hazards, abnormal charging, and vehicle piles in practical applications and environmental aging. Incompatibility, missing test standards, etc.
Nowadays, car companies in various countries have gradually realized that "standards" are the key factor affecting the development prospects of electric vehicles. In recent years, the global charging standard has gradually moved from "diversified" to "centralized". However, in order to truly realize the unification of charging standards, in addition to interface standards, current communication standards are also required. The former is related to whether the connectors are matched, and the latter affects whether the plug can be powered on when it is inserted. There is still a long way to go to unify the charging standards for electric vehicles. Both car companies and governments need to further “open their attitudes” before electric vehicles can have a future. It is expected that my country's leading force in pushing the ChaoJi conduction charging technology standard for electric vehicles will play a greater role in the future.