CHAdeMO charging sequence - hwthomas/ccs-chademo GitHub Wiki

CCS2 Charger interface

A CCS2 to CHAdeMO adapter needs to face both the CCS2 charger and the CHAdeMO car, and provide the CHAdeMO analogue sequence signals to convince the car that charging can go ahead. See https://openinverter.org/forum/viewtopic.php?p=59932#p59932 for CCS1/CCS2 differences, but here only the CCS2 interface is considered.

CP signalling: within the CCS2 charger, the ControlPilot (CP) is pulled to +12V through 1k ohms ready for the car to be connected via the adapter,and this commons the GND (0v) of the CCS2 Charger (PE, pin 5) and the CHAdeMO car (FG, pin 1).

A CCS2 car has a diode in series with 2.74k between CP and Gnd, so a 1k resistor to +12v from CP gives +8.98v at CP (ie +9v, State B), which signals to the charger that communication should start with the car using the HomePlug protocol. The charger then provides a PWM with 1kHz 5% width, +/- 12V amplitude via a 1k ohm series resistor, and this 5% PWM signals to a CCS2 car that it should start responding to the charger on HomePlug.

In a CCS2 to CHAdeMO adapter, pulling CP to < +9v (StateB) must be done with a diode and 2.74k resistor to 0v, then a HomePlug modem in conjunction with the pyPLC CCS2 sequence must respond to the HomePlug comms from the charger. At a suitable point in this sequence the adapter must query the charging parameters from the CHAdeMO car via CAN-bus in order to start the charging loop correctly. The CCS2 charger will start the Homeplug comms when State B is seen, and converse with the adapter (as a a CCS2 car) up to the exchange of car and charger parameters - see Checkpoint 545 in 'Example Flow' - https://github/uhi22/pyPlc/README.md, but the actual charge sequence will not continue until the adapter then pulls the CP line to < +6v (State C).

CHAdeMO charging sequence

Signal names in the CHAdeMO sequence refer to this drawing from the Siemens FB_CHAdeMO function block (Ref 2)
FB_CHAdeMO_schematic

CHAdeMO pin connections

Pin 1 - FG: GND / 0v
Pin 2 - SS1: Charge sequence signal 1
Pin 3 - N/C: No connection
Pin 4 - DCP: Vehicle charge permission
Pin 5 - DC 400v -ve
Pin 6 - DC 400v +ve
Pin 7 - PP: Connector proximity detection
Pin 8 - CAN_HI
Pin 9 - CAN_LO
Pin 10 -SS2: Charge sequence signal 2

CHAdeMO sequence (see Ref 2)
FB_CHAdeMO_sequence

Notes

The 12v power to operate the car's 400v contactors is supplied (in the case of a CHAdeMO charger) via the +12v 'Start-of-charge' signal through pin 2. Typically this is of the order of 1-2 amps, and is not available from a CCS2 charger, which can only supply a low power +/- 12v PWM signal to the car to indicate the start of HomePlug protocol communications. Consequently, a suitable 12v power supply is required for a CCS2-CHAdeMO adapter to operate the car's contactors. The 0v return current flows via the 'Charging-ready' signal through pin 10 when the charger has completed its ground and insulation tests.

The CHAdeMO interface has 2 interlock signals, DCP: Connector-proximity-detection (pin 7), and PP: Vehicle-charge-permission (pin 4). Proximity-detection (7) would be pulled down to 0v via 200ohms by a CHAdeMO Charger and detected by the CHAdeMO car, which disables the car power-train while the circuit is made.

PP: Charge-permission (4) is controlled by the CHAdeMO car, once all compatibility checks with the charger have been completed successfully, and indicates to the charger that charging can start. It can also indicate that there is a problem with the charging, which should be stopped. For a CCS2 Charger, stopping the charging at a high level can be done safely by sending a zero current request to the charger, which must respond before the car can safely open its contactors. The car status and any faults are be monitored by the car CAN-BUS signals, which, via the adapter, must immediately send the charger a zero current request via HomePlug.

There is also the possibility of CCS2 shutdown (as a low-level, hardwired interlock) by changing the CP line from State C/D to State B, and the presentation in Ref 6 states that this should react within 10mS when initiated by the EV. (Ref 7: 5A within 30ms, <60V within 100ms)

References

  1. (https://www.scribd.com/document/839117905/Design-and-implementation-of-a-CHAdeMO-Interface-on-board-vehicle-for-vehicle-to-grid)

  2. (https://support.industry.siemens.com/cs/attachments/109779961/FB_CHAdeMO_en-US_20210118AB.pdf)

  3. (https://openinverter.org/wiki/BMW_I3_Fast_Charging_LIM_Module#Signaling_circuit)

  4. (https://openinverter.org/forum/download/file.php?id=1712&sid=59cf27578e4021c1e6dc01c73f46d8ee)
    Describes the details of CCS charge sequence in a very comprehensive presentation

  5. (https://www.smec.ac.in/assets/images/committee/research/20-21/Design%20and%20implementation%20of%20a%20CHAdeMO%20Interface%20on-board%20vehicle%20for%20vehicle-to-grid.pdf)
    Another source forRef 1

  6. (https://www.youtube.com/watch?v=ejFpBFrVcK8)
    New IEC 61851-23 Edition 2 discussion of Emergency shutdown mechanisms in CCS2

  7. (https://tesla.o.auroraobjects.eu/Design_Guide_Combined_Charging_System_V3_1_1.pdf)
    Is this the same as Ref 4?