HV Batteries below 20% charge

[atokosch]

End goal

transition to shutdown if batteries drop below 20%

Relevant Info/Links

Related to #32 , need to verify that the batteries are not below 20%? charge.

Also related to #92 , if below 20%, then shutdown.

Questions

Will this be interrupt driven?

[atokosch]

Related to #32 , need to verify that the batteries are not below 20%? charge.

Also related to #92 , if below 20%, then shutdown.

Will this be interrupt driven?

[smit-happens]

This will most likely be one of the stretch goals for MS2 at the current rate of development

[smit-happens]

@ShawnPierpont OrionController function for implementation

[ShawnPierpont]

Need to determine if the handling of this is sufficient and what we want to do when the battery is right above 20% to warn the driver of it approaching.

At the moment I have:

20% and <=25% = comment about doing a display change on GLCD 15% and <=20% = set the RPM max limit to 1000 to conserve power, this will serve to also notify the user strongly that the battery is low which is issue #141. <=15% = the car enters the shutdown stage and the tractive system is turned off. The GLV is still on.

[ShawnPierpont]

We still need to test this functionality with the car, but the implementation is now completed. There is a factor stored in the Unitek model called speedCalculationFactor, which is then used in the speed calculation. float UnitekController::calculateRpm(int speedValue) { float percentage = (float)speedValue / unitekModel->MAX_VALUE; percentage = percentage / unitekModel->getSpeedCalculationFactor(); return percentage * unitekModel->getRpmLimit(); }

It was intended to be a simple shift operation but there were data type issues, so it is a division now. The value is initialized in the UnitekController init function: void UnitekController::init(void) { unitekModel = new Unitek(); //set the speedcalculation factor to not modify the value at all unitekModel->setSpeedCalculationFactor(1); }

The only time this value is updated after this is in the processOrion function when the batteries reach 20% charge, at 15% the car will go into the shutdown stage and the tractive system will be turned off.

The handling of the state of charge is done in processOrion in StageManager: ` //first check for pack state of charge issues float packSOC = OrionController::getInstance()->getStateOfCharge(); //maxCellTemperature represents the maximum temperature that we will allow a battery to reach before shutting off the car uint8_t maxCellTemperatureCelcius = 60;

//if the pack is greater than 20% and less than 25%, change the view on the GLCD to notify the driver
if(packSOC > 20 && packSOC <= 25)
{
    //the GLCD will update with a change on the user interface for the driver to know the battery is getting low
    //GLCD_warnSocLow()
}
//if the pack is greater than 15% and less than 20%, cut the max RPM to 1000 to conserve power and be able to return to the original location without pulling as much power
else if(packSOC > 15 && packSOC <= 20)
{
    //set the speed calculation factor to 8 which will make the max rpm sent be 6600/8 = 825 rpms
    UnitekController::getInstance()->storeSpeedCalculationFactor(8);
}
//if the pack is at 15%, shut off the tractive system and continually flash the Orion error light until the GLV system is shut off
else if(packSOC <= 15)
{
    Logger::getInstance()->log("ORION", "Battery SOC too low, shutting off tractive system", MSG_LOG);
    //shut down the car immediately
    StageManager::shutdown();
}
else
{
    //battery is still at a good charge percentage so there is nothing to do
}`

[ShawnPierpont]

Made some small changes to clean up the code and make it more obvious what is going on with the speed calculation factor for the RPM calculation