The GB/T charging standard is a set of GB/T standards, primarily in the GB/T 20234 family, for electric vehicle AC and DC fast charging used in China. The standards were revised and updated most recently in 2015 by the Standardization Administration of China. The term is an abbreviation of 国标推荐, translated as "recommended/voluntary national standard".[1]
The GB/T charging standards are comparable to similar standards from the Society of Automotive Engineers (SAE), the International Electrotechnical Commission (IEC), and the International Standards Organization (ISO) which provide general, physical, and signaling requirements for electric vehicle charging interfaces.
The five referenced GB/T standards were revised and released on December 28, 2015:[3]
Common terminology:
In some cases, the connecting cable is permanently mounted to the charging station and the socket outlet and plug are not used.
GB/T 20234.1 defines three different charging modes:
| 2 | AC (20234.2) | 250 V AC | 10 A | 27.7 kW |
|---|---|---|---|---|
| 16 A | ||||
| 32 A | ||||
| 3 | 440 V AC | 16 A | ||
| 32 A | ||||
| 63 A | ||||
| 4 | DC (20234.3) | 750 V / 1000 V DC | 80 A | 250 kW |
| 125 A | ||||
| 200 A | ||||
| 250 A |
| GB/T 20234.2—2015 | |
| Type: | Electric vehicle charging |
| Designer: | Mennekes |
| Design Date: | 2009 |
| Production Date: | 2013 |
| Diameter: | , male |
| Width: | , male |
| Height: | , male |
| Electrical: | 1 phase AC |
| Earth: | Dedicated pin |
| Maximum Voltage: | 440 V |
| Maximum Current: | 63 A |
| Physical Connector: | VDE-AR-E 2623-2-2 |
| Pinout Caption: | Pinouts for GB/T 20234.2 (male interface) |
| Num Pins: | 7 (1 earth, 3 line phases, 1 neutral, 2 signalling) |
| Pin Custom1 Name: | CC |
| Pin Name Custom1: | Charging confirmation |
| Pin Custom1: | pre-insertion signalling |
| Pin Custom2 Name: | CP |
| Pin Name Custom2: | Control pilot |
| Pin Custom2: | post-insertion signalling |
| Pin Custom3 Name: | PE |
| Pin Name Custom3: | Protective earth |
| Pin Custom3: | full-current protective earthing system—6-millimetre (0.24 in) diameter |
| Pin Custom4 Name: | N |
| Pin Name Custom4: | Neutral |
| Pin Custom4: | single-phase AC |
| Pin Custom5 Name: | L1 |
| Pin Name Custom5: | Line 1 |
| Pin Custom5: | single-phase AC |
| Pin Custom6 Name: | L2 |
| Pin Name Custom6: | Line 2 |
| Pin Custom6: | back-up contact |
| Pin Custom7 Name: | L3 |
| Pin Name Custom7: | Line 3 |
| Pin Custom7: | back-up contact |
See also: Type 2 connector. The AC standard (GB/T 20234.2) uses male and female connectors physically compatible with the European Type 2 connector, but with different configurations and signaling. While the European implementation of Type 2 (IEC 62196-2 Type 2) uses a female connector and male vehicle inlet, GB/T 20234.2 specifies a male connector and female vehicle inlet. Both IEC 62196-2 Type 2 and GB/T 20234.2 specify a female socket outlet and male plug. In addition, GB/T 20234.2 uses CC/CP (charging confirmation and control pilot) signals, instead of PP/CP (proximity pilot and control pilot) signaling.[4]
For the male plug and connector ends, the shape is a flattened circle with a nominal outer diameter of ; the flattened section reduces this to, measured top to bottom.[4]
It allows mode 2 (250 V) or mode 3 (440 V) single-phase AC charging at up to 8 or 27.7 kW, respectively. In Mode 2, power is supplied with a current of 10/16/32A and voltage of 250V. In Mode 3, power is supplied with a current of 16/32/63A and voltage of 440V.[5] Although the seven-pin interface is capable of passing three-phase AC power, the current implementation is limited to single-phase power.[2]
In general, charging speeds are also limited by the vehicle's on board charger, which is usually less than 10 kW. The on-board charger converts the AC input power to DC.
| GB/T 20234.3—2015 | |
| Type: | Electric vehicle charging |
| Length: | , male vehicle connector |
| Diameter: | , male |
| Width: | , male |
| Height: | , male |
| Electrical: | DC |
| Earth: | Dedicated pin |
| Maximum Voltage: | 1000 V |
| Maximum Current: | 250 A |
| Pinout Caption: | Pinouts for GB/T 20234.3 (male vehicle connector interface) |
| Num Pins: | 9 (1 earth, 2 DC power, 2 auxiliary power, 4 signalling) |
| Pin Custom1 Name: | S+ / S− |
| Pin Name Custom1: | Charging communication |
| Pin Custom1: | CAN_H / CAN_L |
| Pin Custom2 Name: | CC1 / CC2 |
| Pin Name Custom2: | Charging confirmation |
| Pin Custom2: | post-insertion signalling |
| Pin Custom3 Name: | DC+ / DC− |
| Pin Name Custom3: | Main DC power |
| Pin Custom3: | positive / negative |
| Pin Custom4 Name: | PE |
| Pin Name Custom4: | Protective earth |
| Pin Custom4: | full-current protective earthing system |
| Pin Custom5 Name: | A+ / A− |
| Pin Name Custom5: | Auxiliary DC power |
| Pin Custom5: | 12V +/-5%, 10A |
The DC fast charging standard (GB/T 20234.3) uses a different, larger connector and allows for fast charging at up to 250 kW, with current of 80/125/200/250A, and voltage of 750-1000V.[6] However, 50 kW or other lower rated power chargers are more commonly seen, typically retaining the minimum GB/T voltage of 750V but with different current ratings. Some chargers may also follow the physical plug specified by GB/T 20234.3 but not the GB/T standard power limits by using a lower voltage than 750V, such as 500V.
The male vehicle connector has a flattened circular shape similar to that of the Type 2 connector used for single-phase AC charging. The DC charging connector specified in GB/T 20234.3 has a nominal outer diameter of ; the flattened top reduces the top-to-bottom height to .[2] There are four pins for signaling: two to provide charging confirmation (CC1 / CC2) and two for communication via CAN bus (S+ / S−). In addition, the GB/T 20234.3 connector provides up to 600 W of auxiliary DC power at 30V/20A (A+ / A−).[2] [4]
, 40% of all electric vehicles sold to date with DC fast charging capability were equipped with GB/T 20234.3 inlets, a plurality compared with the next-most prevalent (Tesla's proprietary inlet, with 19% share), reflecting the scale of the EV market in China. CCS (Combo1 + Combo2) was in third place, with a 17% share including European Tesla vehicles equipped with CCS Combo2 ports, followed closely by CHAdeMO (15%).[7]
Maximum charging speed is limited by a variety of factors aside from the charger's full rated power. For example:
Shortly after the GB/T 20234.3-2015 standard came out in 2015, practical experience demonstrated the locking system did not function as well as intended and the connector was too easily damaged. Although revisions to the 20234.3 standard were planned, it became clear that a new, more robust connector was needed.[7], China Electricity Council and CHAdeMO are working together to develop a new unified ChaoJi system capable of delivering DC power at a maximum rate of 900 kW, with current of 600A, and voltage of 1500V. The new system is planned to replace both GB/T DC and CHAdeMO, and will feature backward compatibility for GB/T DC, CHAdeMO and CCS, all with adapters.[9] [10]
The GBT connector uses CAN BUS signaling for control, specifically, GB/T 27930-2015 is largely based on the SAE J1939 network protocol.[11] This is unlike the power line communication (PLC) control protocol used in the competing CCS standard, which originated from the European Type 2 connector and North American SAE J1772 (Type 1) standards for AC charging.
The signals control the processes of charging, such as handshake initiation and recognition, amperage and voltage configuration, charging and suspension of charging.[11] Charging communication is defined in GB/T 27930-2015 using digital signals following the CAN 2.0B bus protocol at a rate of 250 kbit/sec. In the first handshaking stage, the S+/S- charging communication contacts are connected, then the A+/A- auxiliary power contacts are connected. The EVSE sends a handshaking signal to the EV battery monitoring system (BMS) to confirm S+/S- connection, and once the BMS responds affirmatively, the EVSE begins insulation monitoring, then sends the appropriate insulation-safe message to the BMS. When the BMS acknowledges the insulation-safe message, the EVSE and BMS begin the next charging parameter configuration stage. In this stage, the BMS sends battery charging parameters to the EVSE and the EVSE responds with the maximum output capacity; after this message is acknowledged by the BMS, the BMS evaluates if the EV meets the conditions for charging, then sends a message stating the BMS is ready. Once the BMS-ready signal is acknowledged, the EVSE checks if the charger is ready and sends a charger-ready signal back to the BMS; after the charger-ready signal is acknowledged by the BMS, the next charging stage begins. In this stage, the BMS sends signals to start charging and current battery state to the EVSE, which adjusts output current accordingly in a continuous feedback loop until either the BMS or EVSE sends a stop-charging message.[12]