Improving charging and battery signals

[erikbosch]

This PR contains various improvement suggestions to battery and charging signals.

Major changes:

• Battery identifiers added
• Extension of temperature signals
• State of health signal added
• NetCapacity changed to sensor
• Many Charging signals refactored to allow separate measurements for each phase.
• ChargePlugType now use an array, as vehicles mioght have multiple charge plugs
• Some signals for power loss (to heat) added

[erikbosch]

At the meeting yesterday there were a question on backward incompatible changes, here I try to summarize them including a rationale:

• Vehicle.Powertrain.TractionBattery.Temperature was previously a sensor-signal, now a branch to contain 3 temperature signals Min, Max and Average as a battery pack often have multiple temperature sensors, and it was ambiguous what the old sensor value actually meant, i.e. did it refer to avergae temperature or the maximum temperature?
• Vehicle.Powertrain.TractionBattery.StateOfCharge.Target removed , considered to be the same as Vehicle.Powertrain.TractionBattery.Charging.ChargeLimit, i.e. we could not identify any use-case where both are needed/used
• Vehicle.Powertrain.TractionBattery.ReferentVoltage removed. We had problems finding a definition for what is meant with referent voltage and how it differs from nominal voltage. We already have Vehicle.Powertrain.TractionBattery.NominalVoltage, and propose a new signal Vehicle.Powertrain.TractionBattery.MaxVoltage
• Vehicle.Powertrain.TractionBattery.Charging.ChargePlugType has type changed to string[]. Reason is that a vehicle may have multiple plugs/inlets.
• Vehicle.Powertrain.TractionBattery.Charging.ChargeCurrent and Vehicle.Powertrain.TractionBattery.Charging.ChargeVoltage converted from sensors to branches. The old signals were ambiguous as they did not state if the value was as measured at the charge plug/inlet, or as measured at the battery. Now separate signals has been created for values at charge inlet and at battery, like Vehicle.Powertrain.TractionBattery.CurrentCurrent and Vehicle.Powertrain.TractionBattery.Charging.ChargeCurrent.DC. For charge current separate signals are introduced for DC and AC phases.

[ppb2020]

What is this ID meant to represent? Some serial number? A location in the vehicle? A differentiator in case there are more than one batteries in the vehicle?

[erikbosch]

Description could be improved, the intention is not to specify that this is battery "2" in the vehicle, but rather a (more or less) unique identifier of the battery instance mounted in the vehicle. E.g. serial number, UUID, part_number+serial_number or similar.

As far as I know there are no standard similar to Vehicle Identification Number (VIN) that assures that battery identifiers are globally unique, but I assume that the id (possibly combined with part number) makes it posssible to identify exactly which battery which is mounted.

I will double check with my colleagues and propose an update.

[erikbosch]

Added a comment to clarify that it concerns a "unique" identifier. But the level of uniqueness is up to the OEM.

[danielwilms]

Decision to merge 2022/05/24