Page Comparison

Here’s what the power management board does.

Functionalities

• Check the status of AUX Battery

  • Voltage

  • Temperature

• Check the status of DCDC

I/Os

Questions

Question	Answer
How do we access aux battery voltage and temperature?	Analog Inputs, voltage (voltage divider fed into buffer then controller)
How do we find the status of DCDC?	Analog sensors (same as AUX)
Do we have any protection for the AUX battery?	No built in protection on the board. Software fault can be made. Want to detect: over voltage (would like to discharge the AUX battery without having to remove battery) , under voltage (use time delay to check for under voltage dips), over current (current is analog input) Don’t necessarily need to cut power immediately with power spikes.
Do we charge the Aux battery?	Would like to, but not a priority. (so no).
What’s the valid range of the AUX battery voltage and temperature?	Using a 10s NiMH battery Voltage 9.4 V - 15 V Temperature Charge - 0 to 45 degrees C Discharge - -20 to 50 degrees C

Hardware Person

Josh & Micah Black

AUX Battery / DCDC Status

...

Tells us if all the inputs are working.

Power Select Faults

Complete list:

• POWER_SELECT_AUX_OVERVOLTAGE

•  POWER_SELECT_DCDC_OVERVOLTAGE

•  POWER_SELECT_PWR_SUP_OVERVOLTAGE

•  POWER_SELECT_AUX_OVERCURRENT

•  POWER_SELECT_DCDC_OVERCURRENT

•  POWER_SELECT_PWR_SUP_OVERCURRENT

•  POWER_SELECT_DCDC_FAULT

Fault actions:

• overvoltage or undervoltage fault  of any type - dont shut down, but “attempt to send what is faulting message”

• aux overcurrent or power supply overcurrent - do shutdown (dont send message)

• DCDC fault or DCDC overcurrent - don’t shut down, but attempt to send “what is faulting message” (car should automatically transition to aux supply)

Also to note, we want to make the limit for DCDC overcurrent fault to be slightly more than the current limit that the vicor module already has (which is about 17A, so set overcurrent to 19-20A)