3 kW VEC200 settings

[Murray]

Hi,
I am building an ebike using the HPM 3kw motor with the VEC200 controller. Battery is 58V. I have set up the parameters in the controller correctly...so I believe. However the motor only pulls 20A with full throttle. I have set battery current to 80A.
Throttle is a domino potentiometer type but I have tuned it to run 0.9V - 3.9V and then use the hall setting as I had trouble with the potentiometer setting trying to get it to work.
Valid voltages low and high are set and fault/ max/ min are set as recommended elsewhere on the forum.
Does anyone have ideas why the current would be limited?

Appreciate any help troubleshooting, thanks
Murray

[Bikemad]

Hi Murray andto the forum.

Without having the further details of the battery, the program parameters and testing method etc.

Is the 20A current draw at full throttle with the motor loaded, or is the motor running without any significant load being applied to the output shaft?
If the motor is spinning freely above 4,460 rpm, then 20A current draw is likely to be the most it can pull.

According to the dynamometer test data, to draw 80 Amps from the battery, the motor would have to be loaded sufficiently to prevent its maximum speed from exceeding 4,050 rpm with full throttle applied.

However, if the motor is being loaded below 4,050 rpm at full throttle and is only pulling 20A, there must be something else causing the low current.

What is the maximum continuous current rating of your battery or BMS ?

Is the "58V" battery voltage nominal or measured?
If the "58V" is the measured voltage, make sure you have the Nominal battery voltage (V) set to 48 not 60.

Make sure that the Rated phase current (A) is still set to 210.

If the 0.9V - 3.9V adjustment of the throttle voltage was not done while it was powered by and connected to the controller, the actual voltages could well be different with the controller connected. 

Alan
 

[Murray]

Hi Alan
The 20A was loaded, throttle wide open going up a steep driveway. Bike slowed down noticeably.
The battery is 58V at full charge, so I had it set at 60V on the controller, so good pick up, thanks.  Not sure about the BMS, I have just series/ paralleled some drill batteries as a temporary for testing, they make a 15S4P all up. Used them in the past on other bikes and they can deliver way more amps than 20.  I might whack them on a load bank I have and see how many amps I can pull before they shut down. Or I will hook up a different battery with a bms I can interrogate and see how that goes. If I'm still struggling after that I'll start screenshotting my parameter settings....

[Murray]

Okay, quick update. Changed battery setting and also adjusted throttle settings a little bit. I noted I had valid voltage at 4.0 V not 3.9V so I brought it down to match and pulled back max allow V to 4.2V with fault exit at 4.1V.
It worked, pulled 79A up the drive.
Probably should of only changed one thing at a time as I'm not sure what made the difference, throttle changes or battery setting change. Wouldn't think a 0.1V range adjustment would make a 60A difference...
Something to figure out tomorrow!

[Bikemad]

It worked, pulled 79A up the drive.

Good to hear you've got it sorted.

Probably should of only changed one thing at a time as I'm not sure what made the difference, throttle changes or battery setting change. Wouldn't think a 0.1V range adjustment would make a 60A difference...

The culprit will be the 60V Nominal battery voltage setting, as this would have caused the controller to start reducing the current when the battery voltage reached 55V.

If your pack was only at 58V (3.87V per cell) at rest, the voltage would soon drop below 55V (3.67V per cell) under load.

With the 48V setting, the battery pack voltage will now have to drop below 44V (2.93V per cell) under load before any current reducing will occur.

Alan