Kelly controller in "Torque" mode

[hejo]

Hi,

after blowing two Crystalyte controllers (I did not know that it is so effective to destroy controllers if you put fuses, switches in wire from Minus-Pole from battery)
I ordered two controllers from Kelly, because they promise Torque Control.
One of the controllers worked nice , right out of the box, the other one went on fault.
I spent a day trying all kind of settings ... programming... etc. until i found that the conroller simply rejects any power supply above 39V.
My fully charged LIon battery is 42V.
After consultation with Kelly they provided new firmware, which solved this problem.

My main objective however was, to operate my trike-tandem in Torque Control instead of Speed control.
Changing the settings of the Kelly however did not show any noticable difference.
After quite a few emails with Kelly I am quite confused and disappointed now, since it seems impossible to achieve what I wanted!
Kelly controller´s rated current is 50A.
In settings you should be able to limit max current from 20% to 100% of rated current.

My definition of a Torque control :

- controller set to 60% = 30A maximum current (Kelly defines current as motor current, which is ok, because motor current should directly be proportional to torque)
- throttle of 1V should result in 6A motor current, 2.V should result in 15A, 4V throttle should result in 24A motor current.
- at 1V throttle (6A) motor should run at full speed at no load
- at 1V throttle the motor under load should stay at 6A and speed should be a result of load

Observation however : even at 1V throttle, the controller sends more than 20A (battery current read on CA) to the motor in stand still, causing my vehicle / chain drive to shake!
Kelly writes about the difference between motor current and battery current.
But acording to my limited knowledge motor current must always be higher than battery current!

Kelly writes that Torque control means 25% influence of speed, 75% influence of torque.

I could accept this, provided if throttle is 2V then current should not exceed 12A (5V=30A, 1V=6A )
But my controller jumps on 25-30A from stand , once i touch throttle just slightly.

There are only two possibilities :
- my understanding of a torque control is wrong / stupid
- the Kelly controller is not capable of running in Torque mode / torque control

Could somebody try to enlighten / clarify / help

Thanks

Hejo

 

[Jozzer]

The Kelly brushed controler I have really does have "torque control", hoever the brushless version I have also behaves as you describe. A little throttle is enough to get lots of power down. The implimentation doesn't seem the same.

 

[fechter]

There are only two possibilities :
- my understanding of a torque control is wrong / stupid
- the Kelly controller is not capable of running in Torque mode / torque control

Could somebody try to enlighten / clarify / help

Thanks

Hejo

I'd be inclined to go for the second choice.

I built my own version of a torque control circuit as an add-on to my Crystalyte controller. It works as desired. At low throttle settings, the torque is very minimal, but if I'm going downhill or have a tail wind, the speed will eventually reach the full throttle speed.

Perhaps something in their software is not quite right yet.

 

[hejo]

Is´nt it much easier to design a torque / Amps control as compared to speed control?

How nicely did the CA throttle override current limiting function of Justin work with the Crystalyte controler work. I just dont have the CA version allowing me to use the throttle to set the current limit.
It is really a pitty to have now two expensive Kelly controllers who do not perform as anounced.

 

[methods]

Hmmm, I use my Kelly in torque mode.
If I am climbing a hill I will set it to whatever current I feel is acceptable. For instance, if I set my cruise control to 10A (via CA) then I pull a steady 10 amps the entire climb.

Sure there is some overshoot with dynamic loads but I would expect that. The alternative is a poopy over damped response.

Have you tried to desensitize your throttle? Slow down the throttle response and try to make the power come on more smooth? I am guessing this could help.

Anyhow, for the record, in general my Kelly holds torque (current) roughly where I set it.

-Patrick

 

[hejo]

you are using the CA set to 10A ?

If i set my CA to limit current /torque, then everything works fine.
I expected the Kelly controller to do the same : to limit the current as per throttle position.
But it does not.
In torque mode it still controls speed. Unfortunately

 

[HAL9000v2.0]

my Kelly works fine i torque mode. On every speed torque is allmost the same and it goes up to 30,5A on battery side adjusted on 60% max. In speed mode on long hills you can feel How he "loses power".

 

[methods]

you are using the CA set to 10A ?

If i set my CA to limit current /torque, then everything works fine.
I expected the Kelly controller to do the same : to limit the current as per throttle position.
But it does not.
In torque mode it still controls speed. Unfortunately

No, my CA is set to 200A
I am using my Cruise Control to set the torque.
I set to torque mode then set Cruise control. What ever voltage the cruise control is set at is the torque I will pull.

Mind you this is the steady state torque. You cant expect a step function where it will go from zero amps to 10 amps then back to zero amps. There will be overshoot with dynamic load.

If your controller does not do this then ask Kelly for a firmware update as torque mode works on my controller.

-methods