General Category > Electric/Hybrid Car Conversion
Club Car with 10kw and 500A controller. Only 21mph??
Bikemad:
Hi Jovan,
Is the motor driving through the original gearbox/final drive unit?
If so are you using low gears at slow speed and on hills?
If my rough calculations are correct, the 29Nm of motor torque being produced at the rated 10kW output would require a total gear reduction ratio of ~11:1 to climb a 10 degree slope, and this should achieve a maximum of ~18mph (~30km/h) at 3500rpm with a 500mm diameter tyre.
I initially thought it might be temperature related, but from what you have said, it appears to reset too quickly for a temperature related problem.
I therefore suspect that the batteries might be overloaded under high current draw causing a large voltage drop, which is causing the controller to reduce the power going to the motor in order to prevent the battery voltage from being pulled too low.
Do you have a voltmeter connected to see exactly how low the battery voltage drops under heavy load?
Perhaps the 10kW of power and 29Nm of torque is just not enough for a 620kg vehicle, considering that the original petrol engine produced 38 kW and 69 Nm of torque.
Just as a comparison, the Vectrix VX-1 scooter weighs 210kg and its motor can produce up to 35kW of peak power and 65Nm of torque. It has a single fixed 3:1 gear reduction and has no problem accelerating at low speeds or climbing hills.
Alan
TheKing:
Hi Alan,
I'm sorry for the delay in answering. Let me tell you more about my problem.
Yes, I use the original Daewoo Matiz gearbox where the first gear has a 4.15: 1 ratio and is very slow for the uphills in my city and I use the second gear more often.
You have correctly concluded that temperature is not the cause because it's happen on cold controller and motor.
By the way, my intention is to use my vehicle for city traffic, my city has 40,000 inhabitants, so in a radius of 3 km I have everything I need and I am satisfied with the range of the vehicle of min 30 km. I only have a problem with losing power, speed its not priority.
I plan to connect a voltmeter tonight or tomorrow to see how the vehicle behaves under load.
I wondered, maybe I should change something in the parameters? .... so if you can look at * .foc file my last parameters that were entered through the USB cable ...
Regards
Bikemad:
If you can attach the .foc file (don't use a "*" in the filename ;)) I'll see if I can spot anything obvious that might be advantagous to change, but measuring the voltage under load will hopefully help to pinpoint the cause of the mysterious power loss.
Alan
TheKing:
Good morning Alan,
I just finished testing the vehicle by measuring the voltage under load ... and that's what we expected .... I started with 100% full batteries (51.6 V), and under higher load the voltage drops to ~42v and then loses strength. I looked at the app, "low voltage protection value" cannot be changed, it is determined, so I think I need to change something around the current ...! I hope there is a solution ...
Otherwise, like info, use batteries as in the picture, a model underlined in green.
Regards,
TheKing:
Again looked at the app, "low voltage protection value" CAN be changed .... and I put now on 39 v and everything is fine now .... my test is positive, on uphill voltage drop to 40.6 v but not lose power ....
Thanks for support and advice ...
Regards,
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version