More on the proper application of a DC-dc convertor

We have learned that the DC-dc convertor being rated at 99.9A@12Vdc output is actually capable of much more and in the mode we are running it does not self limit.  Therefore we need a circuit to limit the flow between the DC-dc and the lead acid battery while not limiting the DC-dc to Car, or Battery to Car.

Our learnings suggest that if the DC-dc is connected straight to the battery at 12.xV charge, the DC-dc will output as much as it can to bring the battery up to 13.2V instantaneously.

As is today.

Circuit below is shown same as above, but needs to be changed for the wanted operation.  An on-board DC-dc RV charger has been suggested.  Other suggestions?

Wanted:

1.  OEM lead acid OR DC-dc should be able to run the OEM fuse panel.  Currently the car goes completely dead including the windows, locks, charging port release, and alarms.

2.DC-dc should support/float the OEM battery during driving.

3.The DC-dc should shut ENTIRELY down when not driving to reduce OEM battery drain.

4.DC-dc can be on during charging, but when charging completes it should shut down to avoid drain.

5.DC-dc should start after clamping and shutdown before Main relays release to avoid wielding.

Second out of town drive

With the cooling system installed we decided to chance a road trip.  Successful 48.4 miles.
Lessons learned:

1. Regen ON causes far more heat build up than with Regen turned off.  Regen is when the energy from slowing the car down is reabsorbed through the motor and placed back in the battery system for reuse.
2. The accelerator pedal is setup such that the first 1/4 of the pedal travel is Regen, and then Acceleration.  There is enough regen capability that the actual brake system does not need to be used in regular driving.   FYI, the Regen system activation does cause the brake lights to turn on.
3. We need more cooling; it is not clear yet whether the pump is not pumping, if there is a blockage in the lines, if the system has an air bubble, if we need the fan on the radiator blowing, or if we just need a larger pump.  Regen is off until we figure this out.

UPDATE:

The cooling system is completely functional, there was an air bubble caught in the system.   Excessive regen use does heat up the motor core more than the motor housing, but the system has not auto de-rated since install of the cooling system.

More control relays

As we are preparing the car to become more and more computer controlled we need more relays.  A circuit board was found with many solid state relay, individual fuses and individual LEDS already attached.  The board was cut in half, it was twice as long and mounted in the top of the airbox that already has the DC-dc convertor in it.  Additional cooling was also added such tat when the DC-dc turns on its 13.2Vdc output the fan turns on.

BANG SSsssss

In an attempt to trim the voltage up to 13.2 on the DC-dc converter output a mistake was made.  The result being two blown slave modules in the DC-dc convertor.

The system has 4 main parts, 3 modules on the left, and the motherboard (MB) on the right.  As it turns out the three modules on the left are the same, BUT one has a short removed.  The left most (labeled M) is the master and via a signal back to the MB the other two modules run in slave mode.

In the first system we received the master was in the middle position, when we attempted to TRIM the left position nothing happened.  To diagnosis the issue the buss bars were removed from the output despite it clearly stating on the cover not to.  The result was unregulated output from the two slaves and BANG PSssssssss.

A new (used) system has arrived and been confirmed to be assembled in the proper order.   For the mechanical in mind the user manuals were not clear, but the VICOR staff have been very patient and attentive.  Thank You Vicor for the support of an old piece of equipment, and Parts2GO for again providing a working unit.

The current dilemma is how to prevent the DC-dc from outputting more than 100A to bring the battery up to 13.2V.