Controller Supply Voltage and Fan Update

Surging

During the last few test drives, I noticed that the motor tends to have a slight periodic surge when approaching maximum rpm.  It is subtle when cruising at a constant speed, but a slight pulsing or surging could be felt.  This led the following investigation:

1. The Kelly KBH 72710 controller is rated for a supply voltage of 8V-30V.  This is the supply for the controller's functions, not the main drive power which is 85V in Jane, with the controller rated at 90V.
2. The system currently has an adjustable voltage booster to covert the 12V standard car supply upward.    TI LM2577 Link
3. Previously, the booster was set to output 18V to supply the controller.
4. I can't remember why I landed on this but there were  published reports that 12V was insufficient.
5. While reviewing the Kelly datasheet again for the controller, it says that 24V is "preferred".
6. So, a few small turns of the screwdriver and the booster is now set to output 24V.
7. During a test drive today, the surging seems to have stopped.  But it will take a bit more testing to confirm.

Not sure why this was not noted previously but it can only help.  

Cooling

In the next attempt to cool the motor, a local machine shop is fabricating a blank disc to replace the fan in the Motenergy ME0913.  John from Motenergy provided the mechanical drawing for the fan assembly.  The fan carries the hall phase magnets so it is a critical component of the motor and can just be simply removed.  The current theory is the fan, though running in reverse (CCW from the fan end)  from its designed direction (CW from the fan end), is frustrating (impeding) the air flow through the motor.  With the blank disc, there should be no interference or obstruction for the air.  Currently, the cooling system is just on the verge of being sufficient, so if by removing the fan, there can be a 10%-20% gain in flow, the results should provide sufficient headroom.

Dashboard

Work continues on the electronic dashboard.  Here is the latest design:

Boot Up Screen  (Yes, that is an image of Jane Austen)

Sitting Idle

After pulling out from a stop sign

A few highlights:

1. The graph shows power consumption and regeneration in half second intervals.  The bars are color coded to make for quick interpretation.  It will show about the last 30 seconds of data and continuously rotates
2. Watts appear to be the best indicator of system strain and is closest to RPMs for a gas engine.  Thus the real-time motor watt consumption is now shown with the large numerals.  They are set to change color based on the following:
1. Regeneration in effect = Green
2. Less than 12KW (Continuous power limit for the motor) = White
3. 12KW - 18KW =Yellow
4. >18KW = Red - The motor's 1 minute rating is 30KW
5. This is a computed value based on values reported by the controller - Motor Amps ( % of controller rating - 700A) x Battery voltage at the controller x PWM % (pulse width modulator duty cycle)
3. The other values are also color active to help the driver quickly spot an issue.  Much like gas cars, the driver is responsible for managing the system.  This is no different than red-lining a gas engine or ignoring a check-engine light.   The car will let you do it but should warn the driver of the situation.
4. The large "Forward" indicates whether the motor is in Forward or Reverse
5. Warnings and error messages are displayed across the bottom of the screen when needed.