Charging limits DC charging
Precharge
For precharge the SECC needs to be parametrized.
- PAR_PreChargeVoltageOffset is used to define the offset for the requested charging voltage from the SECC. This is done to prevent a reverse current flow directly after closing the switches.
- PAR_PreChargeCurrent is in accordance with ISO 15118 set to a low current (up to 2A) to signal the SECC that pre charging is requested
- PAR_DCThresholdVoltage defines the maximum allowed difference between inlet and vehicle Voltage to signal ready to close to the VCU. If the threshold is exceeded, the switches won't be closed by the CHARX EVC-100.
during precharge CHARX EVC-100 communicates VehicleVoltage + PAR_PreChargeVoltageOffset and PAR_PreChargeCurrent as values for precharge to the charger. If | InletVoltage - VehicleVoltage | < PAR_DCThresholdVoltageCCL will report CCL_HVSW_State = Ready to close.
End charging
If a button is configured and PAR_ShutdownDirectly == TRUE the CHARX EVC-100 will trigger end charging cycle at any state.
To ensure, that the switches does not take additional damage the present current is observed during end charging sequence. The allowed current during switch opening can be adjusted via PAR_MinChargingCurrent (default value in accordance with CHARIN design guide)
To ensure, that there is no risk of electrical harm at the inlet, the CHARIN design guide requests to check present inlet voltage. This voltage can be adjusted via PAR_DisconnectInletVoltage (default value in accordance with CHARIN design guide)
Reduce charging power
To prevent an emergency shutdown caused by temperature the CHARX EVC-100 supports a function to reduce the TargetCurrent in DC charging in accordance with the current inlet temperature. This feature can be enabled and disabled by PAR_ReducePowerEnable. The CHARX EVC-100 will communicate external requested charging current via CAN CCL_ChargingCurrent. Temperature range for function can be set by PAR_ReducePowerInletMinTemperature and PAR_ReducePowerInletMaxTemperature.
Pause / Restart charging (CP-State BCB-Toggle)
To enable the customer to start a second charging cycle without removing the plug manually this optional feature stated in IEC/TS 62763/Ed.1 implemented:
Possible use case: A vehicle is placed at the charging station for overnight charging. This ends around midnight. To start in the morning with a conditioned vehicle and a full charged battery a second charging cycle starts in the morning automatically, and the vehicle can go to sleep in between.
To trigger this function, the signal VCU_RestartChargingCycle needs to change from False to True.
Same mechanism is used to pause a charging cycle. Instead of VCU_ChargePermission = FALSE VCU_PauseRequest = TRUE can be used to stop the actual charging and after a while (with or without sleep cycle) the charging cycle can be continued with same settings as before. The Charging cycle can be restarted by Charger (switch on CP-PWM leads to EVSE_State = Resume) or by vehicle (B-C-B-Toggle).
Please note this feature needs a compatible charger. This feature is not implemented in many chargers!
Safety measures
Disconnection on load
If a disconnection is detected, the HVSWs are opened directly.
Lock closed observation
The lock is permanently observed while the switches are closed. This safety measure can't be disabled.
Communication observation
Observation of CP communication interruption can be enabled and disabled by PAR_FuncObserveCPCommunication.
During charging CAN communication is observed if any signal is received. If no CAN message is received within 1second charging will be ended normally.
Temperature observation
In current release temperature observation prior closing of the switches can be adjusted via PAR_MaxChargeStartTemperature if temperature is above this limit the HVSWs won't be closed.
During charging the maximum allowed temperature of the Inlet can be adjusted via PAR_TempMaxInletDCTemperature.
Emergency disconnect
If the CHARX EVC-100 receives VCU_EmergencyShutdown = TRUE, the switches are opened directly.
If PAR_CANMonitorE2EProtection is enabled CAN communication is observed. If the CHARX EVC-100 does not receive VCU_EmergencyShutdown = FALSE, the switches are opened directly.
Reverse current flow
If PAR_FuncCCCeckLow is set to enable the CHARX EVC-100 observes if charging current is less than PAR_MaxUnintendedReflowCurrent and open switches.