Sensorless LYEN Controller+Turnigy RC Motor Maximum RPM Test

[inspiredvoltfreak]

Hi everyone, just signed up,
I am hoping you could give me a pointer. I am planning a highway speed trike conversion and have started ordering parts. Unfortunately I ordered a Turnigy 80-100-A 180Kv Brushless Outrunner http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=5139 not realizing it said the motor was rated for 48 Volts MAX. I was planning on running 4 Lead acids which of course will give me close to 57 volts when fully charged. Is this going to be a problem? I'm thinking i may have to scale back to 3 lead acids and double up the amp hours instead but i really don't want to do that. Inside the motor is it just wires or is there a circuit board with voltage sensitive components on it?

 

[olaf-lampe]

Hi everyone, just signed up,
I am hoping you could give me a pointer. I am planning a highway speed trike conversion and have started ordering parts. Unfortunately I ordered a Turnigy 80-100-A 180Kv Brushless Outrunner http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=5139 not realizing it said the motor was rated for 48 Volts MAX. I was planning on running 4 Lead acids which of course will give me close to 57 volts when fully charged. Is this going to be a problem? I'm thinking i may have to scale back to 3 lead acids and double up the amp hours instead but i really don't want to do that. Inside the motor is it just wires or is there a circuit board with voltage sensitive components on it?

Welcome on ES!
For the motor batteryvoltage doesn't matter, as long as you don't exceed the max. RPM. At 57V it is a little above 10.000rpm which is no problem for them. The voltage will drop soon anyways. At nominal voltage your motor will spin around 8600RPM ( no load).
If you want to discuss this further, please start a new thread in the nonhub drives section .

Good luck on the highway *gulp*
Olaf

 

[inspiredvoltfreak]

Thanks for the reply! I am loving reading about other peoples builds with the RC motors. So much power at such low price point and pretty much guaranteed to be efficient! If only batteries could catch up with this technology. Thanks again Olaf!

 

[Spacey]

I've been having a spot of bother with the new 12 Fet Sensorless controller from Lyen. My setup is:

9C 2807 26inch wheel 12awg phase wire upgrade and cooling holes made.
20 Cell Headway 16ah pack
12 Fet Lyen sensorless edition

No load speed is perfect all the way up to top speed. Bit of a grumble judder when accelerating hard past 10mph....but for me the problem is that at higher than about 25 to 27 mph if I give the throttle more than 75% the wheel judders like it's about to go into reverse and the amps shot up to 79 amps peak.

The wheel was very very hot with all the juddering but the contoller was very cool. I'm happy with the contoller other than the juddering. With a 26inch wheel I can't be doing that many rpm? It really feels like the timing goes way out of sync as the rpm get higher.

This set up is good for 37mph, was able to use full throttle when going down a hill only using 9amps, but as soon as the amps are needing I.e on the flat the juddering kicks in very strong.

Does anyone have a fix?

 

[Spacey]

I did read somewhere that if you put the phase wires so that the bike goes into reverse.....then solder the jumper on the pcb so that the co triller goes into reverse I.e the bike will now go forward then the juddering stops?

This would maybe imply that the timing advance would then work in reverse thereby fixing the top end issue at the expense of the low speed starts?

 

[Jeremy Harris]

I did read somewhere that if you put the phase wires so that the bike goes into reverse.....then solder the jumper on the pcb so that the co triller goes into reverse I.e the bike will now go forward then the juddering stops?

This would maybe imply that the timing advance would then work in reverse thereby fixing the top end issue at the expense of the low speed starts?

You're hitting the commutation speed limit that these sensorless controllers have, I believe. You may get some improvement by tricking the controller with the reverse wiring and switch, but I am reasonably sure that the real problem is the limited ability of the sensorless unit to run at hiugh speeds.

I know the hub motor isn't runnign very fast, but it does have a large number of pole pairs, so it's commutating a lot faster. It's the electrical rpm that matters here, unfortunately.

Jeremy

 

[Spacey]

Damn....I thought the rpm would be that of the wheel as a whole rather multiplied by the poles of the motor. That is going to suck for efficiency as I am running a good 8mph slower than the motor is capable of before the juddering kicks in.

I'll give the reversing bit a go and see how that gets on. Was hoping to let rip with the new phase wires I had installed along with the drill holes. It certainly does feel like a timing issue that gradually advances into the high end speed.

Are there any solutions do you think with regards to the hardware?

 

[John in CR]

Are there any solutions do you think with regards to the hardware?

Sensored operation. Interesting results though. The 9C has 46 magnets, so it's 23 poles. My motors have 24 poles and running in 20" tire I was able to get up to about 30mph before the motor starting sounding different and didn't have power to accelerate much past that (I can do 60mph with sensored) with my Lyen sensorless. Mine is the old type with the add on sensorless board, and I thought the new ones are capable of higher rpm. Mine ran out of steam at about 500rpm at the wheel or 12krpm electrical. I never had any judder or anything, only an odd sonic with high currents above that point and not a sudden transition.

How was the sensorless startup with your 9C Spacey? Mine is even smoother than sensored.

Hey Lyen, push on those engineering guys on your end. We need a good to 40krpm electrical. I personally will buy 8 or 10 more controllers right off the bat once this is solved. Guinea pig me even when they claim 25krpm.

I'm a bit disappointed the electrical mental horsepower around here hasn't solved this one already. Isn't the MCU in these controllers and/or sensorless add-ons already plenty fast to handle the computing speeds needed?

John

 

[Spacey]

Start up was pretty smooth and very very quiet, slight rumble judder at about 15 mph sometimes, but not something that would bother me. Maybe it was just the luck of the draw and I got a dud one lol, I seem to attract them....36v charger just went POP after plugging it into the mains power supply, was not even connected to the battery pack and was only a few weeks old having done 6 charges :lol:

But this build with the Sensorless controller on is on my pride and joy Canondale which I've just spent the last 2 weeks holiday stripping down and rebuilding the whole thing. Including upgrading the phase wires to 12 awg and drilling vent holes in.

Build quality on the controller is excellent and the instructions were great, just wish I had known about the speed cutoff whilst sending the wheel nearly into reverse at high speed thing before. The controller does stay amazingly cool though.

The weird thing is that I only get the massive judder jerking of the wheel when any power is applied, freewheel or downhill it is fine on full throttle but any load and bam!

It definitely feels like it loses sync as the rpm of the wheel speeds up, Lyen agrees on trying the reverse trick, I don't mind if the starts are messed up as long as the top end is good. It really does feel like the controller progressively advances the timing to the phase wires with higher speeds to the point where it wants to judder or go backwards.

Hoping there is a hardware solution as I wanted to hotrod this bike by maybe getting a 8*8 9C and upping the voltage with lipo.

 

[Spacey]

Have spent the day on the bike with the new Lyen Sensorless 12 fet controller, whilst vie had to pull the top speed back a bit to stop the juddering I have compensated by putting the block time up to 5secs and ramming some amps into the upgraded 9C 2807 wheel.

Damn this thing pulls like a train, I think the trade off of top speed against the silence of the Sensorless controller and total uber grunt it now has was well worth it.

One bad thing though that is totally my fault, due to having huge dropouts on my Canondale Gemini I have not been running any torque arms, mainly due to the weird rear dropout design. Have not used regen or regen braking really before but enabled it on the new controller.

Good job I checked the bike over as the axle has been swinging left and rit and was not far away from a spinout! Am about to fit two thick torque arms on it today.

Can not get over how quiet my wheel is now that I have gone Sensorless.

 

[MitchJi]

Hi,

How was the sensorless startup with your 9C Spacey? Mine is even smoother than sensored.

Damn this thing pulls like a train, I think the trade off of top speed against the silence of the Sensorless controller and total uber grunt it now has was well worth it.

Can not get over how quiet my wheel is now that I have gone Sensorless.

Smoother startup, quieter and pulls better?

I'm a bit disappointed the electrical mental horsepower around here hasn't solved this one already.

If its that much better me too.

 

[Spacey]

Well it's a lot quieter for some reason, it used to groan and tick with sensorless now its a lot quieter on pull away.

Although if you just go wide open throttle from a standing stop it can sometimes go slightly out of sync so I gradually open the throttle, but this tends to stop after the bike has warmed up which is odd. Sure I've lost a bit of the top end due to rpm sync issues but being able to chuck big phase wires into the axle due to not having hall sensors and the ease at which this controller is programmable makes up for it.

Now I can hit a block time of 5secs which gives me full 40 amps on pull away until it reaches high speed, would not have wanted to do that on the bell wire 16 to 18AWG phase wires that come with the 9C as standard.

 

[Jeremy Harris]

Well it's a lot quieter for some reason, it used to groan and tick with sensorless now its a lot quieter on pull away.

Although if you just go wide open throttle from a standing stop it can sometimes go slightly out of sync so I gradually open the throttle, but this tends to stop after the bike has warmed up which is odd. Sure I've lost a bit of the top end due to rpm sync issues but being able to chuck big phase wires into the axle due to not having hall sensors and the ease at which this controller is programmable makes up for it.

Now I can hit a block time of 5secs which gives me full 40 amps on pull away until it reaches high speed, would not have wanted to do that on the bell wire 16 to 18AWG phase wires that come with the 9C as standard.

I'm going to guess that the reason it's quieter etc has to do with the sensors being in the wrong place in the motor. My experience of fitting sensors to outrunners has been that they run quieter and smoother with sensors (in the correct position) than they do when run sensorless.

I'd suggest that this motor sounds like an ideal candidate for some testing with Burtie's timing adjuster. I bet it'd make a substantial difference to the way it runs on a sensored controller.

Jeremy

 

[Spacey]

oooohhh now that sounds good, because I totally agree on the timing being out and being able to change the timing advance would be great and get me my top end back.

Any link?

Think I found it...reading through it now:
http://endless-sphere.com/forums/viewtopic.php?f=2&t=19054

Edit: Yep looks exactly what I need, I had a feeling it was timing, certainly felt like it.

 

[LI-ghtcycle]

These 12 FET sensorless controllers sound really interesting! Do these come with adjustments for LVC, HVC, regen braking, cruise control & Max Amps?

If so, I believe this will be my next purchase!

 

[Spacey]

It does depend on how many amps you will be using though as over a certain amount causes the controller to judder a lot. It seems okay around 25mph though. I will be selling mine (few weeks old) as it does not suit the speed my vehicle needs to go at.

 

[LI-ghtcycle]

It does depend on how many amps you will be using though as over a certain amount causes the controller to judder a lot. It seems okay around 25mph though. I will be selling mine (few weeks old) as it does not suit the speed my vehicle needs to go at.

I would be using it mostly to run my 12S LiPo powered 9 x 7 Amped DD, but eventually I would want to run 14S and about 35A, but I would love to be able to use it to also run a friction drive if I can limit the voltage and amps, i.e. have a high voltage limit of 21V (this way I could make a 8S pack act like a 5S and not have to buy new batteries) and if it also had other options like cruise control and adjustable amp limit, LVC, it could be sort of a "jack of all trades" for me to use in either set-up in testing.

***EDIT**** Forgot to mention with the friction drive I would be limiting the amps to 80A or less, 50A might work just fine actually.

 

[mr.electric]

Has anyone tried the Lyen sensorless + astroflight on a bike yet? Any comments I'm ready to give it a shot for a build I'm helping with but wonder if it will be a waste of time to redo a known test and result.