Sending voltage/current to powersupply even the voltage is greater than 0

[martinlukas84]

The standard ISO15518-20 [V2G20-2183] describes the provided EV target voltage and current in ChargeLoopReq from EV.

The voltage and current shall never send in the same message. In the current implementation, the voltage and current is only sent to powersupplyDC when voltage is greater than 0. But The voltage is only sent at the beginning of the chargeloop (and in other states). After that, only the current is sent peridically. This leads to the problem, that the current is never sent again during chargeloop. We can't found any limitation regarding voltage >= 0 in iso-2. We assume that this change does not influence the existing implementation of DC.

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[mhei]

I'm not sure... when lastest_target_voltage cannot be negative, then the check can be removed completely?

[kwoyhope]

In my understanding, EV uses constant-voltage-mode(varying TargetCurrent) or constant-current-mode(varying TargetVoltage), and the V2G_CI_DC.xsd(15118-20 schema) shows that both 'EVTargetCurrent' and 'EVTargetVoltage' should exist(not optional) in the 'Scheduled_DC_CLReqControlMode'. (and there's no 'EVTargetCurrent/EVTargetVoltage' in Dynamic_DC_CLReqControlMode.)

[martinlukas84]

Sorry for the confusion. The current and the voltage are part of the message, but only one of both is greater than 0. The other one is equal 0.

[SebaLukas]

For me [V2G20-2183] does not make sense for me.
I also looked into the iso15118.gitlab.io forum and there is already a discussion about this requierment. It has been agreed here that [V2G20-2183] does not make sense and that the requirement will be deleted again.

[kwoyhope]

Sorry for the confusion. The current and the voltage are part of the message, but only one of both is greater than 0. The other one is equal 0.

IMHO, EV(EVCC) may not set 0 value for this case.