Looking for a brushless controller with PWM

I've been building some self balancing vehicles and I use an arduino outputting pwm to drive them.

glennselectric.blogspot.com

Now I want to control a brushless hub motor. I'm having trouble finding something that meets my spec:
-48v
-100 or so amps peak
-direct and instant control of speed and direction with pwm ( this is the tough spec)

I'm not afraid to build one, and I'm not afraid to buy a cheap Chinese one.

Thanks!!

All brushless controllers use PWM, but I think your question relates to the need for on-the-fly speed and direction control, doesn't it?

If so, then the vast majority of brushless controllers can't change direction on the fly, they need the throttle to be taken to zero, then the direction changed and then the throttle increased. They often don't seem to be able to do this quickly, probably because there isn't an ebike or normal electric requirement to change direction quickly.

There are ways to do it, but it means delving into the realms of DIY controllers. At the simplest level, a dumb commutator, like the MC33033 (see here for an example http://endless-sphere.com/forums/viewtopic.php?f=30&t=23350) will reverse on the fly, so you can change direction at any throttle setting. It's fast enough for a self-balancing scooter, I'm sure, but is a pretty crude way to do things. The other way is to look at using FOC control, or similar control methods, like that in Lebowski's controller. This should allow fairly easy speed and direction control, especially if you use the CANBus control option.

Looks like lebowski has what I'm looking for. Hope it's not beyond my technical ability...

Thanks!

Glenn

lebowski said his will not work...

Looking at your, eh, vehicle, is it some sort of self balancing segway type thing ? For this
my controller is not suitable...
Mine is meant for a bicycle or car type vehicle. When you select reverse my controller will
jump into a regen mode where it slows the forward motion down to almost standstill in
a controlled manner (so with a limited braking force, much like taking your foot off the gas
in a normal car). Once at standstill reverse is implemented and you can drive backward. It
will not instantly reverse when the vehicle is still in forward motion like you would need for
a self balancing vehicle...

I cant believe i cant find one on the internets!

I did find this for $ 515.00 http://www.a-m-c.com/download/datasheet/dzcante-060l080.pdf

A simple BLDC controller using the MC33033 (or hardware commutation) will do as you want, reverse on the fly. Most ebikes and electric vehicles have no need of this capability, so that can't do it. Because there's no demand for reverse on the fly controllers for vehicles no one seems to make them at a reasonable price.

I'm reasonably sure something along the lines of the simple controller I made (which is used on an electric boat now) would work for a self-balancing scooter. It has a direction input and an analogue voltage throttle input, which could possibly be driven from a simple D/A using PWM from a ucontroller, or better a ucontroller D/A output. It will flip direction at any throttle setting and doesn't do any sort of safety checking first, as vehicle controllers usually do.

On the boat I find the ability to just flick a switch to go astern, irrespective of throttle setting, quite useful, which is why I now use it. Previously I had a Xiechang controller and that needed the throttle to be reduced to zero before the controller would switch direction.

Making a hardware-type BLDC controller isn't that hard, but the chip I used, the MC33033 is now obsolete I think. I'm sure there may be other hardware BLDC controller chips around, though, or you could make a 6 step commutator with a few ordinary gate chips.

The goldenmotor BLDC controller will provide a claimed 100amp peak at 48v and if you look at the programming screen it would suggest that it has the ability to select reverse on the fly. (immediate as opposed to unimmediate, as they put it)
I've not tried this functionality so YMMV) http://www.goldenmotor.com/e-Bike-DIY/PI-200%20GUI.jpg

Not exactly what you're after but illustrates the speed of transition achievable with a conventional reverse:

http://endless-sphere.com/forums/viewtopic.php?p=659073#p659073

Hi all,

I am quite new to this forum but really interested in microcontrolers and self balancing devices.
Here is a link to my website where I started to play with brushless motors : http://freedom2000.free.fr/HDD_Still_Clock_index_eng.html

I have also designed my selfbalancing unicycle based on a Microchip's PIC24F + MPU6050 3 axis accelerometer + Gyros and a MagicPie3 motor + controler
The result is nice and works quite well

[youtube]ZT8x_HIqY2s[/youtube]

However if you carefully listen the "music" you will hear that when braking the motor tries to go to reverse mode and "cracks"
The forward/reverse is probably not hte best solution to implement braking
My opinion is that it would be better to :
- balance when forward
- regen brake rather than going reverse
- when almost stalling go to reverse

For this I will probably read Lebowsky's thread as it could be very helpful
He says exactly what I would like to try !
" When you select reverse my controller will jump into a regen mode where it slows the forward motion down to almost standstill in
a controlled manner (so with a limited braking force, much like taking your foot off the gas in a normal car). Once at standstill reverse is implemented and you can drive backward. It
will not instantly reverse when the vehicle is still in forward motion like you would need for a self balancing vehicle...

So what I need is a controller with PWM controlled regen braking AND speed monitoring (hall sensors) AND fast reverse mode

JP