Link to Previous Proposed Changes for Pre-Charge:
Link:
New Suggestions
Motor controller capacitors are currently charged with a constant voltage source and series resistor. This is always 50% efficient. For a challenger vehicle, it might be better to have a switching circuit (buck topology) to charge with constant current (which would also be faster).
Keep to 12V by removing DC DC inversion
Add hall effect sensor
Make simpler by removing irrelevant portions (e.g. fan control and thermistor may have been exclusive to MOV since shorts less of an issue?)
Research Summary
Simplify Charge Pump and Depletion Mode FET
U4
Original parts
Charge pump switch regulator
Depletion mode FET
New Change
Find closed switch to replace the two components
Part requirement
Normally closed relay
Support
151.5V + safety factor
0.5A
Controllable
Can close on-demand or
Closes when car close
Implementation
Remove
Charge pump and corresponding capacitors
Pull-down resistor
Keep
LED and resistor
Current limiting resistor
Solid-state relay
https://www.digikey.ca/en/products/detail/ixys-integrated-circuits-division/PM1206/654953
600V and 0.5A
AC
https://www.digikey.ca/en/products/detail/ixys-integrated-circuits-division/CPC1963G/2417218
600V and 0.5A
AC
https://www.digikey.ca/en/products/detail/panasonic-electric-works/AQZ204/646377 Preferring this one?
400V and 0.5A
Datasheet below
https://www.mouser.ca/ProductDetail/Panasonic-Industrial-Devices/AQZ204?qs=Wn4D5qJAqBLvGIN%2FDTrEgw%3D%3D (mouser link)
Smaller changes
Removing:
Fan control
Remove fan connector
Remove entire fan control sheet
Thermistor
Remove thermistor connector
Remove entire thermistor sheet
Add jumpers near AND gate to skip it