Paul & Sabrina's cheap DIY 144v motor controller

[Cyruscosmo]

Hello Again!

Wow! Things got really Interesting since the last time I was here around page 300 and two years ago. My intentions then were to convert a 94 Toyota truck but life had other plans for me. Since then I have helped my neighbor build an electric dragster, a couple cars, a boat and a bark O lounger. I have started and finished my new shop, built an apartment over it for my Mom who is now 74 and I am ready to build my own controller!

So I have finished reading this forum from where I left off, Paul has moved further away, (was it something I said ;-)) and the controller has changed a LOT. I no longer have the truck but my neighbor has sold me an already converted Geo Metro, which was a conversion he did a couple years ago for someone else. The metro had not been chopped up and was straight and in need of a little TLC.

First thing I did was remove all the stuff the owner had "redone"... The guy was an engineer yet he ran two ( + and -) thumb sized pack cables side by side through a sheet metal hole, with no grommet, to the controller and shunt, which he mounted UNDER the metro in place of the old fuel tank.

So I had a lot to redo and a few normal repairs like new brakes, wheel bearings, and axles in front and new over sized brakes and bearings in the rear. The repairs are finished and I am now rebuilding the motor to flywheel adapter. The flywheel is being remade to be a lot lighter and still have a functioning clutch.

The car came with Nickel metal hydride batteries from somewhere I have not been able to track down and a Curtis controller. I have since gotten hold of 90 Winston 60 AH LiFePo batteries and am sorting out the bad from the good, so far only 4 have failed the tests.

So Paul... ;-) What became of the BMS that you were working on? I find that I am in need of one for all these cute little LiFePo cubes. And do you still have parts and such for a 500 amp controller that I can use with a power section of IGBT's like jackbauer built? I am pretty sure 1000 amps would do nasty things to a geo metro's transaxle.

But as soon as I find me a BMW Z3 we will talk about some real amps!

Cyruscosmo

[duncan]

Hi Paul
I'm having to get this house ready for sale - at the same time as building the new one
But I am getting on a bit with the car
Changed the springs for lighter ones
100 Lbs/in - front
125 Lbs/in - rear
Finally fixed my speedo!

Now the controller - I'm making up the endplate for the low power end
Question
Do I need the serial connection or is it all done through the Pickit?

I've downloaded the MPLAB software - and the manual - I will install it soon
still looks scary!

[jedsmd]

Originally Posted by duncan

Hi Paul
I'm having to get this house ready for sale - at the same time as building the new one
But I am getting on a bit with the car
Changed the springs for lighter ones
100 Lbs/in - front
125 Lbs/in - rear
Finally fixed my speedo!

Now the controller - I'm making up the endplate for the low power end
Question
Do I need the serial connection or is it all done through the Pickit?

I've downloaded the MPLAB software - and the manual - I will install it soon
still looks scary!

Duncan
If you are happy with the software as Paul provides it than you don't really need the serial port. If you like to tweak the variables yourself, than that is done through the serial port using realterm.

Also Flores is working on a web based monitoring system that will use the serial port.

Glad to hear you are back working on the car. Looking forward to progress reports.

The MpLab looks scary because it is written for the tech savvy, but I did not find it too hard to work through.

• Save the file Paul sends you to your harddrive
• Click File than Open to open Paul's file.
• Select dsPIC30F4011 from the pulldown menu for Device.
• It asks you if you are sure you want to program a 5v device - click yes.
• You should be able to select your pickit from the pulldown menu for Tool. ( I had to power on the controller to get this to work.)
• Then push the program button.

A few seconds later you get a cryptic message that it is done.

Note these instructions are for MpLab rather than MpLabX. MpLapX is probably similar.
Jerald

[jedsmd]

Paul
For the new controller what are the checks the controller logic makes?

• High pot?
• 12 volts too low?
• High voltage too low?
• High current at zero throttle (hardware check?)
• Others?

Thanks

[MPaulHolmes]

high pot.
+24v
+5v
current sensor feedback > 0 (disconnected would mean 0)
desat detection checks for like 6v drop across the igbt while on
any igbt over 600amp.
there may be hardware undercurrent protection, but I forgot at the moment (on cell phone).
check for disconnected throttle in software (not in hardware).
High voltage isn't checked. it would be happy with a AA battery. haha. Top speed would be relatively low, as well as range would be reduced.
check of base plate temperature. limits max throttle in 8 stages depending on temperature. 75degC to 85degC.
sensorless over-rev protection isn't enabled at the moment. the code is there though.

[jedsmd]

Originally Posted by MPaulHolmes

high pot.
+24v
+5v
current sensor feedback > 0 (disconnected would mean 0)
desat detection checks for like 6v drop across the igbt while on
any igbt over 600amp.
there may be hardware undercurrent protection, but I forgot at the moment (on cell phone).
check for disconnected throttle in software (not in hardware).
High voltage isn't checked. it would be happy with a AA battery. haha. Top speed would be relatively low, as well as range would be reduced.
check of base plate temperature. limits max throttle in 8 stages depending on temperature. 75degC to 85degC.
sensorless over-rev protection isn't enabled at the moment. the code is there though.

Thanks
So does the contactor drop out if something fails in the power section?

[MPaulHolmes]

if desat happens, the igbts will be disabled. if they fail, current won't fall. hmm... it would be one extra line of code to open the contactor if desat or hardware overcurrent fails to cause curremt to go to zero. thats a good idea.

[duncan]

Hi Paul
I have installed end plates with the connection bits,
The cooling is almost finished,
I have installed mplab,
(and I'm busy grinding my concrete floor - it's all taking much longer (and costing more) than I thought)

Where can I find the software to install?
What I'm hoping for;
1000amps at 5Kohms throttle pot
Fast ramp time - 0.1 seconds or faster
Thermal protection

I'm not using the controller to operate my contactors - doing it manually!

To install I need?
12v to the controller
The PiCkit connected to my PC and to the controller
Do I need throttle or any load???

What are the pinouts on the PiCkit compared to the ones on your board?

Thanks
Duncan

[MPaulHolmes]

Hi Duncan, I'll email you the new code hex file (and c code if you want it).

I love manual contactor control!

Yes, you need to provide the controller with 9-18v.

The pins on the pickit are the same as on the board. The dot next to pin 1 on the board is the same as the pin with the triangle pointing at it on the pickit 3.

To program it, you don't need anything connected except power to the control board and the pickit 3 connected.

[duncan]

Hi Guys
Got the cooling plate attached also the two end plates,
Paul has sent the software so I will have to fight with that
keep fingers crossed