Sensored or sensorless controllers?

[richirich1113]

I am new to the ebike thing and this is my attempt to understand the difference in controllers. What would be the advantages/disavantages between a sensored or sensorless set up? I believe i have a sensored controller and motor since there is the phase wires and hall sensor wires coming from the motor into the controller. Would a sensorless controller still run the motor without having to hook up the hall wires and run on just the phase wires? Does the sensorless just bypass the halls so as not to have to worry about burning out the halls?
Any info or where to get it would be greatly appreciated,
Thank you

 

[DAND214]

Yes a sensorless controller will run buth hubs. With or without halls. In most cases the hub/controller with halls is a smoother operation.

Some controllers will do with or without sensors. A good thing to have as a spare.

dan

 

[richirich1113]

So let me see if im getting this right, This is my situation. I have a sensored controller and motor, if the halls were to go out in the motor i would still be able to run the sensored motor with a sensorless controller?

Thanks for the info DAND214

 

[richirich1113]

New update. I have been researching all morning and i have found the information that i was looking for.
No more information needed.
Auugghh! The information is endless, Thanks Endless-sphere.

 

[SamTexas]

New update. I have been researching all morning and i have found the information that i was looking for.

Can you share the infos that answer all your original questions? I would like to know to.

 

[el_walto]

So let me see if im getting this right, This is my situation. I have a sensored controller and motor, if the halls were to go out in the motor i would still be able to run the sensored motor with a sensorless controller?

Thanks for the info DAND214

Yes if the halls fail, you can then run the motor with just the 3 phase wires connected to a sensorless controller.

 

[richirich1113]

http://www.methtek.com/2011/11/12/72v-sensorless-30/

The info here really answers what i was wanting to know about the controller differences.
Hopefully it answers your questions.

 

[dogman dan]

For the next guy who comes along reading this, it's worth noting that not all motors with internal planetary gears work well with all sensorless motors. The freewheel can make geting started a problem.

For direct drive motors, yes, a sensorless controller can be a very good quick fix for a burnt hall in a motor. I have both types and like sensorless just fine for "normal" street riding. I prefer sensored on the dirt trails, or the racetrack.

 

[Pure]

For the next guy who comes along reading this, it's worth noting that not all motors with internal planetary gears work well with all sensorless motors. The freewheel can make geting started a problem.

For direct drive motors, yes, a sensorless controller can be a very good quick fix for a burnt hall in a motor. I have both types and like sensorless just fine for "normal" street riding. I prefer sensored on the dirt trails, or the racetrack.

Whats the difference in operation performance between the 2 on the same motor Dog? I would assume the sensorless will want to studer at low speeds?

 

[d8veh]

When running with hall sensors the motor is better at starting, smoother, quieter and slightly more efficient. Mainly the differences are small. Best policy is to get a sensored motor and a controller that can work in both modes - like those sold by BMSbattery. If you get any problem with the sensors, you can then switch to sensorless mode. The disadvantage of hall sensors is that they fail if they get wet or too hot or when the solder joints break through vibration/age.

 

[dogman dan]

With a gearmotor, the sensorless controllers that I have had trouble starting because of the motor freewheel. Once going, they'd run.

For dirt riding, it was more awkward to get started when you were parked on extremely steep slopes. They don't want to start right if they are rolling backwards at all. But low speed was not a problem, just had to be creeping forward a few mm to start fine. That's why I run them just fine on the street, which rarely is so steep.

For racing, well, the risk of the motor losing synch and stuttering when entering a corner at 35 mph was not a good thing. The sensored controller I tried did not run reliably at higher rpms. I wanted good solid sensored operation on the track. But the flip side is the possibility of a hall failing mid race.

 

[RuggedRiderAUS]

So I'm thinking of getting a NEW SensorLESS Controller for my Broken SENSORED Motor. Or of the controllers that can switch and do both would be nice as well.

My Motor's most likely not working because the Hall Sensors are out or maybe something to do with the controller.
I have a 48V 1000W Brushless Non-Geared Hub Motor. Does anyone have a good recommendation where or what kind of New Controller I should purchase? I was thinking either Lyen or BMSBattery Controller from what I've reading about so far. 8)

Any recommendations on a Specific New Controller I can buy for for my set up? I haven't been having luck finding exactly what I need..

 

[solarshift]

controllers from theese guys seem pritty good, I got one a few monts ago and Ive been using it with a motor that sonds like yours and its been relly good, cheep, regen, and it works sensorless well, havent tried sensord but it dose have conections for sensors and the sellers were really cooperative.
http://www.aliexpress.com/item/Free-Shipping-48V-1000W-45Amax-BLDC-motor-controller-E-bike-brushless-speed-controller/497637202.html

 

[fourbanger]

It was actually my understanding that sensorless motors *needed* to have a bit of rolling momentum before throttle could be applied. As such, I'm kind of at a loss as to how a geared hub motor with an internal freewheel can operate sensorless at all...

 

[spinningmagnets]

I think it's very useful to have a sensorless controller as a backup, and also as a trouble-shooting tool.

By that I mean, if your motor develops a serious problem, then swap-in the sensorless controller. If it then runs fine, then at least you know the motor phases are OK.

Another benefit is for those times when many years later you try to run a sensored controller with a different motor. The wire color-codes are often different from one manufacturer to the next. Sensorless controller will run fine, even if the colors on the wire are wrong. You can swap around the three fat motor phase wires until you get the motor running in the correct direction, and a wrong wire combo will not damage anything. This is an easy way to add a reverse to a heavy cargo bike.

With the five tiny hall sensor wires, you must first identify the positive and negative (ground) wires, before attempting to swap the three signal wires around (to find the right combination). If you get the positive and negative wrong, you can fry a Hall sensor. There is no consistency in the color codes of the hall sensors from one manufacturer to the next. At least 90% of them use red/black for the pos/neg wires...and a few had no color code, the assemblers just "knew". I think they wanted home builders to fry the halls. They want you to take problems to their licensed dealer for repairs.

 

[amberwolf]

FWIW, not all sensorless controllers require externally-started motion to work. Lebowksi here on ES has solved that problem for the new version of his controller. There's probably others, too, in the higher-end stuff.


Regarding geared hubs and sensorless controllers, my experience so farwith one system is that the controller "bang-bang"s between directions, so that it decides which is forward by the higher current draw direction, and continues going that way. Another one just always goes in whatever direction you've setup the phase wires, and if it is the wrong direction you swap any two wires to fix it.

 

[arthurtuxedo]

FWIW, not all sensorless controllers require externally-started motion to work. Lebowksi here on ES has solved that problem for the new version of his controller. There's probably others, too, in the higher-end stuff.


Regarding geared hubs and sensorless controllers, my experience so farwith one system is that the controller "bang-bang"s between directions, so that it decides which is forward by the higher current draw direction, and continues going that way. Another one just always goes in whatever direction you've setup the phase wires, and if it is the wrong direction you swap any two wires to fix it.

Do you know if the Phaserunner can also start from zero in SL mode? I was planning on picking one up soon for my eZee 250r with fried Halls. The current SL Infineon sputters until about 10 MPH

 

[fourbanger]

Holy cow. Pretty good turn around time on the replies for a 6 year old thread, guys. Thanks.

One thing I'm a little unsure of now is whether or not a person can run a hub motor backwards at full speed (perhaps using the freewheel side of a DD motor to drive the LEFT side of the rear wheel, for example) in conjunction with the hall sensors, or if that would have to be done in sensorless mode.

Also, here's some information I found on the subject from digikey. A lot (OK *most*) of it is over my head, but maybe someone else searching here might be able to make good use of it.

https://www.digikey.ca/en/articles/techzone/2013/jun/controlling-sensorless-bldc-motors-via-back-emf

 

[amberwolf]

One thing I'm a little unsure of now is whether or not a person can run a hub motor backwards at full speed <snip> in conjunction with the hall sensors,

Works fine with any motor that has neutral timing on the sensors. All the DD hubmotors I've had appear to be. I"m not sure about geared hubs, but unless you disabled the internal freewheel/clutch it wouldn't matter on those anyway.

With some controllers that have a reverse feature, some of them don't apply full power when in reverse mode, but most don't seem to care. Presently I'm using two generic controllers on the trike's rear wheels, different brand on each side; left side is sensorless only, right is sensored only. Both have a reverse wire. On the sensored one, the good phase hall combo I found first was backwards, so I just used the reverse wire to fix it, since I couldn't seem to find one that worked forwards. Runs at full power/etc anyway.

I also ahve a reverse switch (horn button on the bars) that sets both motors to reverse, and that also has full power.

OT, but since one is already in reverse all the time, I actually use a relay to control both of their reverse wires, so pressing the button on the bars switches the relay, and the relay switches the controllers, on in NO mode and one in NC mode, since I can't simply directly connect them. Technically I could probably just swap any pair of phase wires on the sensorless one to reverse it, and then tie the reverse wires together on the button, without the relay, but since I'd alreayd soldered the phase wires on the sensorless at that time, the relay was easier.