FYI: New WE controller is sensorless

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avsmith66

10 mW
Joined
Aug 14, 2008
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I just recently received a new Wilderness Energy BL-36 kit and have confirmed that the included controller said to handle 50amps is sensorless. The motor hub is also brushless yet it only has three wires.

Upon opening the controller I discovered that it only contains 50v capacitors, and it has a small square "daughter" board wired in to the controller but not attached with padding around it and suspended in the controller case along the top. When starting from a dead stop, the motor shutters and vibrates but does start without pedaling.

If this is already known information, then sorry for the wasted space, but I have yet to find anything mentioning this in the E-bike forums, and this was a major source of confusion for me until I figured it out with the help of Knuckles post about the new sensorless boards which this controller seems to have in included in it.


AVS
 
That is how sensorless controllers work. They try different phase combination's until it finds the correct one. So your motor will shudder and shake until it gets the right combo.
 
can you post up pictures of the WE controller? does the sensorless module resemble the one that keywin is adding to the infineon controller? 50V caps would be expected if it is rated as a 36V controller, can you read the part numbers off the FETs? thanks, dm
 
The "stuttering" can kick in at low speeds as well as when starting from a dead stop. I find it most commonly occurs when I hit a bump. The motor will stutter pretty violently until you close the throttle. Once you put the throttle back on it, it seems to smooth out right away. It limits the usefulness of the brushless motor for off-road riding. The stuttering is violent enough to possibly hammer the dropouts. I'm going to be getting a torque arm for this motor very soon.

The brushed motor is way smoother at low speed, but truly does use 30% more energy. I've got both versions and I've checked the power use with a Watts Up meter. The brushed motor (BD-36) averages about 26 watt hours per mile while the brushless motor (BL-36) runs about 18.5 wh/mi on the same trip. That's running 20+ mph with the throttle mostly wide open while pedaling with some small hills. When being very light on the throttle and pedaling at lower speeds, the BD-36 can get about 17 wh/mi and the BL-36 about 12 wh/mi.
 
Thanks for the info. Do you have any data on the amp draw on the two motors, flat ground, and full throttle? I've been guessing that my WE brushed draws around 20-25 amps at full throttle.

I have really liked the brushed motor, but it sounds like the sensorless may be real nice for riding in the wet parts of the country compared to a sensored motor.
 
I also have a newer WE BL36 and based on my CA - the max I've drawn is 28amp. A typical draw is between 20-24amp at full throttle on flat ground. This is same whether I run 36v or 48v - go figure.
 
The amps is the same, but the watts is more at 48. Since the BD uses 30% more power, I could be closer to a 30 amp draw than I thought. I hope my Ping can hack it. So far it has, but I was hoping I was spending more time at 1c discharge. Well speed costs money I guess. Hopefully I'll get two years out of it, like 700 cycles.
 
Dogman -
I've logged about a dozen rides on my BD-36 with a Watts Up meter. At 36v, my peak amps have ranged from 32.8 to 33.6 with an average of 33.3. Peak watts ranged from 1126 to 1162 and averaged 1141. The longest ride was about 12 miles. Most are about 3 (my normal commute).

My normal commute is mostly flat with a few gentle hills. I can average 20 mph but drop down to 15 or maybe less on the hills. I ride with full throttle whenever I can. I haven't checked the power demand on a strictly flat road. The fact that the peak watts varies so little from ride to ride suggests that hills are not the culprit. Some of my rides included steep single track path and these rides didn't have much higher amp draw than the flat ones. It's probably starting out where the amperage peaks come from. I always pedal when starting out and don't hammer the throttle till I'm rolling 5 mph or better.

After reading your post about timing the brushes, I'm wondering if my motor could benefit from that. The peak watts seem really high for a motor rated at 600 watts. Maybe this winter I'll take it down and try your brush adjusting trick on it.
 
avsmith66 said:
I just recently received a new Wilderness Energy BL-36 kit and have confirmed that the included controller said to handle 50amps is sensorless. The motor hub is also brushless yet it only has three wires.

AVS
Click to expand...

Hmm. So the motor won't work with sensored controllers then, unless the controller can work in a sensorless mode. Makes for fewer controller options.
 
According to my CA the new BL-36 draws 20-22 amps on flat and it peaked at 33 at some point, but I have not ever actually seen it draw that even on a hill. I'm running 48v Nicads and the top speed is 26mph. No load speed is 37. 35wh/mile.

I don't have pictures of the inside of the controller right now, and have no way to know if the small board is the same as the one in the Infineon, because I do not have one to compare it to, but I'm working on that.

Attached is a picture of the motor cable from the controller.



AVS
 

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  • motor_cable1.JPG
    motor_cable1.JPG
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Thanks for the amperage info. This is what we really need to know to choose a battery. Not some , deflated to look legal wattage number. Clearly my ping is taking a bigger beating than I thought. I began to suspect that might be the case when my motor melted this summer. Well if I'm killing my pack, it's not showing it yet, but I would like a 48v anyway. Now I know I'll want it in a 30 ah. I suspect the BD motor may draw almost as much amps as a chrystalite phoenix.
 
Hey, wait a minuite. If I rode using a drain rate of 1c, my 20 ah pack should be empty in an hour. But in fact, I can ride it at least an hour and a half. even if you subtract about 15 minuites for stop lights and such, you still can't be draining at a rate more than 1c if you last that long. So my average rate of discharge must still be around 20 amps or less :D
So I should see close to the cycles in the test for my cells, 1000 cycles to 80% I'm sure I pull 30 amps plenty of times on the way, and the controller shutting off lets me know that sometimes its more than that, but in general, I must be pulling 20 amps or so average. Maybe even less. I do peadle a heck of a lot, but I never thought it was 10 amps worth.
 
I still have not seen mine get anywhere near pulling 30amps. Like I said the CA had a peak at 30, but watching it I don't know when it could have been. Since my last post I have taken the bike out with my 48 volt nicad packs which combined are only 6ah and my 36 volt pack which is 3x12v 18ah SLA's and so far 19-22 is the only thing I have seen on avg and that is including going up hills and starting from a dead stop. Again though this is with a BL-36 and the new sensorless controller. I have no idea how that should compare to your BD.

AVS
 
DSC_1535.jpg

DSC_1536.jpg




AVS
 
I added some solder to the two shunts in the WE controller today. Just a good size blob of solder in between the two wires Took the bike for a test ride. It boosted the amp output by about a few amps according to my CA. Before adding the solder the BL-36 motor would draw 19-21amps. Now it peaks at 35 and draws 24-27 on starts and levels off down to 18-19amps at 25mph. Still running at 48volts. The controller will not handle more than that due to the 50v caps.

I would regularly pedal assist the bike on takeoff to get going from a dead stop to get across an intersection quickly, and now that is no longer necessary, as the bike has much more torque.


Attached is a picture of the shunts.
shuntmod_1538.jpg




-AVS
 
Care to expand on that?

-AVS
 
i wonder if that little daughter board contanins the BEMF detectors and some logic to convert a sensored controller board to sensorless?

i guess we will find out once one of the tech gurus gets one to disect.

rick
 
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