Buick Lacrosse 2012 e-assist moto-alternator

Electric Motors and Controllers
e-vektor
100 mW
100 mW
Posts: 46
Joined: Sep 22, 2013 10:30 am
Location: Spain

Buick Lacrosse 2012 e-assist moto-alternator

Post by e-vektor » Dec 23, 2016 5:43 pm

Hi

I am starting this e-motorcycle project with GM moto-alternator 24261691 AA (Buick Lacrosse 2012 e-assist alternator)
It is rated for 150 N*m at 230 Arms, but I am having lots of problems to reach 70 N*m
I am using Curtis 1236 80V 350A Controller

Self-tune process gave a Slip gain of 9%, and this gave about 50 N*m, but increasing it step by step I got 70 N*m, but no more

Anyone has some advice to check the setup?

here a video of first dyno start:

https://www.youtube.com/watch?v=PES5hT- ... e=youtu.be

Some specs:
Part Number: 24261691 AA Continental
AC Induction 8 pole Radial Flux Inrunner
Water/Glycol Cooled Stator
115Vdc Bus
15-18kW peak (20 HP)
TQ: 100 N*m a 1330 rpm
150Nm at 230Arms (peak)

Tomdb
10 W
10 W
Posts: 94
Joined: Apr 03, 2014 7:47 am
Location: Warwickshire

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by Tomdb » Dec 25, 2016 7:28 am

seen this post?

http://elmoto.net/showthread.php?t=2676

Turns out the torque is quoted at engine crank and not alternator.

Are you pushing the full current that the Curtis can produce through it?

e-vektor
100 mW
100 mW
Posts: 46
Joined: Sep 22, 2013 10:30 am
Location: Spain

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by e-vektor » Dec 25, 2016 12:02 pm

That explains several things. I got the whole torque (160 n*m) in the brake which has similar ratio to the alternator with respect the engine in the car.
I put 250 a rms for this test (230 specified by the manufacturer)

This is not a problem regarding power, but this invalidates my original calculation for transmission. I wanted to use 13 teeth at motor and 48 at wheel. But with this new info I probably have to go to lasercut sprocket with 100 teeth

Here it can be seen how the field weakening starts at 850 RPM (with 75V battery)
Image

e-vektor
100 mW
100 mW
Posts: 46
Joined: Sep 22, 2013 10:30 am
Location: Spain

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by e-vektor » Dec 29, 2016 4:28 pm

I am struggling measuring the efficiency of this motor (battery power vs mechanical power), but I am getting very bad results.

For low speed values, say 300 rpm, I am getting values of 30% eff or so. And for values close to the nominal speed (850 rpm at 75V) efficiency with different current values go from 50% to 55%, no more. I would have expect to have at least 80% at higher speed / low torque areas, but not, it is always below 55%.

I tried different slip gain values, and the value that creates more torque is 16%, although Curtis set it to 9% after self-tune. Of course the more slip, the less efficiency, although in a narrow range.

Some ideas? is there some way to run the Curtis 1236 to drive the motor in a more direct way?

e-vektor
100 mW
100 mW
Posts: 46
Joined: Sep 22, 2013 10:30 am
Location: Spain

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by e-vektor » Dec 30, 2016 10:55 am

a quick update: by now I recalibrated the dyno, now it shows +15% more torque, this makes that efficiency is now between 60% and 65% in most cases. And some of them (I cannot repeat) close to 70%, but no more. I had expected to have at least 80% in wide areas, but it is 60%.
I did lots of tests with different currents, different slip gains (mainly 9% and 15%), different speeds, and the best ones are always between 60% and 65%

I also did a quick max HP test and it gave 9.5 HP with 75V. If voltage was 115V (as in car) I should have 9.5 / 75 * 115 = 14.5 HP, which is very close to the official value (15 HP for traction)

should I expect more from this motor, or I definetively assume that this is its maximum?

Tomdb
10 W
10 W
Posts: 94
Joined: Apr 03, 2014 7:47 am
Location: Warwickshire

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by Tomdb » Dec 30, 2016 3:20 pm

The motor can probally take more voltage or more current. If you want to find out what it can take just start raising the voltage to the limit of the controller. Why are you using such a low voltage controller?

For short bursts you van easily get the motor to take more current, did you hook up cooling and are you measuring the temperatures?

e-vektor
100 mW
100 mW
Posts: 46
Joined: Sep 22, 2013 10:30 am
Location: Spain

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by e-vektor » Dec 30, 2016 5:20 pm

battery voltage and controller were a bad decision at the begining of the project. Anyway this motor can be reconnected to delta, then 115V (star) is equivalent to 66V (delta), so I think I will be able to test it more propertly. Indeed in some efficiency maps I saw on the Internet, max efficiency only happens at higher speeds when high field weakening is being active.
In some way, probably I am trying to measure efficiency in a worst scenario, similar to have a 230 vac motor connected to a battery inverter. As the map is quite complex, probably I am reaching bad eff points at all corners

next step is to include the voltage channel and the current sensor to automatize the process, and to be able to acquire a whole ramp at fixed current. (next one would be to write some code to draw a 3D map, but this will be later)

yes, motor has the hoses installed, radiator and it is filled with coolant. I do not have the water pump yet, but it takes some minutes until it gets hot. Normally it reaches 60ºC to 70ºC (housing) at the end of the tests (which are short)

e-vektor
100 mW
100 mW
Posts: 46
Joined: Sep 22, 2013 10:30 am
Location: Spain

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by e-vektor » Dec 30, 2016 5:26 pm

detail of motor connection:

Image

Harold in CR
1 MW
1 MW
Posts: 1775
Joined: Feb 01, 2010 7:19 pm
Location: Costa Rica

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by Harold in CR » Dec 30, 2016 6:28 pm

Is there any possibility of drilling and setting a number of small pill magnets into the rotor and turning this into a PMDC motor and using a Lebowski chip modded controller like the IMA or a Volt controller ? These motors are readily available and cheap, and can be water cooled to control the heat as I believe might be your intension.
Thanks to Justin, the forum is open source and NON-commercialized.

e-vektor
100 mW
100 mW
Posts: 46
Joined: Sep 22, 2013 10:30 am
Location: Spain

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by e-vektor » Dec 31, 2016 4:55 am

I think so, in the other forum (elmoto) someone was talking about that, but I think he didn't complete the modification. I saw pictures that people that do that in small appliance induction motors, like fans or so, mainly for using them as generators
But in this case my interest is controlling an induction motor because I thought that it had some advantages at high speed range and good power density, although I have to admit that by now it is being a little frustrating and disapointing as efficiency is very low.

e-vektor
100 mW
100 mW
Posts: 46
Joined: Sep 22, 2013 10:30 am
Location: Spain

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by e-vektor » Jan 04, 2017 9:37 am

more updates:

I've just automated the voltage and current measuring (previously I was doing it manually with an amp clamp), and now I am starting to get better results. I doble checked everything and it seems right, so I am not sure why it was worse when doing it manually

first a picture at 280A from 700 rpm to 1500 rpm. Here efficiency starts at 45% as expected, but it reaches a value close to 70%

Image


And here the same test at 140A. Surprisingly it reaches a value between 75% and 80%

Image

Note: where it shows "horsepower" actually it is mechanical power in KW measured at the electric current brake

Harold in CR
1 MW
1 MW
Posts: 1775
Joined: Feb 01, 2010 7:19 pm
Location: Costa Rica

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by Harold in CR » Jan 04, 2017 11:38 am

I posted in another forum, about changing to PM, but, was told it won't work well. Are you still playing with AC ? Do you plan on doing a home brew controller, similar to Tomdb ?

I am going stateside next week and can purchase used items reasonably. Just don't know squat about electronics, yet. I DID buy a recommended book, though. :roll: :lol:

I'm very interested in this for low voltage, 120V or so for moto conversions.
Thanks to Justin, the forum is open source and NON-commercialized.

Tomdb
10 W
10 W
Posts: 94
Joined: Apr 03, 2014 7:47 am
Location: Warwickshire

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by Tomdb » Jan 04, 2017 2:50 pm

i think that running it at partial load (thus partial amps) will result even higher efficiency, oops noticed you did run lower load :) .

Also the efficiency is measured at the dyno brake, what is between the motor and the dyno that could result in losses?

This motor would be a good match for the Johannes Huebner inverter kit plus a honda IMA powerstage.

e-vektor
100 mW
100 mW
Posts: 46
Joined: Sep 22, 2013 10:30 am
Location: Spain

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by e-vektor » Jan 04, 2017 5:13 pm

Harold in CR wrote:I posted in another forum, about changing to PM, but, was told it won't work well. Are you still playing with AC ? Do you plan on doing a home brew controller, similar to Tomdb ?

I am going stateside next week and can purchase used items reasonably. Just don't know squat about electronics, yet. I DID buy a recommended book, though. :roll: :lol:

I'm very interested in this for low voltage, 120V or so for moto conversions.
I think that for this motor the magnets modification can be difficult as it has 72 stator elements, but I don't know if this means 72 magnets, or just 8 magnets as it has 8 poles. Anyway it seems too much work, and I want to experiment ACIM motors.

Yes, I would like to build an inverter, but I am not sure if at this moment it makes sense as there are big amount of open source projects.

I think this motor can be good up to 20 HP with the original configuration working at 115V, or if doing the conversion star to delta it could be ran at 72V (for 20 HP), or at higher voltage, say 144V for 40 HP, but I still want to see the efficiency figures when the right voltage is applied. I need to know if I have to expect the 60% eff values during light operation (low speed/low torque), or 80% eff values (with the delta configuration)
Anyway, I don't think I am going to use another motor, at least for this project.

Indeed, I would like to see how far can I go with this motor, as a personal challenge, even I have to use high voltages and IGBTs such as 300V, but I am not sure how much time I could expend on this

e-vektor
100 mW
100 mW
Posts: 46
Joined: Sep 22, 2013 10:30 am
Location: Spain

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by e-vektor » Jan 04, 2017 5:18 pm

Tomdb wrote:i think that running it at partial load (thus partial amps) will result even higher efficiency, oops noticed you did run lower load :) .

Also the efficiency is measured at the dyno brake, what is between the motor and the dyno that could result in losses?

This motor would be a good match for the Johannes Huebner inverter kit plus a honda IMA powerstage.
yes, I am trying to create an eff. map, anyway the expected values at low torque / low speed areas are also low. The only area that seems good by now is the field weakeing area at low torque, like in this picture, in which the F.W. effect is very noticeable. A motor like this one should be ran with a very short gear, always in the F.W. area.

Image

I am using a dyno that connects the motor with the brake using a chain. It can have some losses, but they does not seem very high, specially at low speeds which is when the motor has the worst eff. values

Yes, IGBTs will match very well this motor. I would expect up to 80 HP at 300V, but by now, step by step...

e-vektor
100 mW
100 mW
Posts: 46
Joined: Sep 22, 2013 10:30 am
Location: Spain

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by e-vektor » Jan 05, 2017 11:10 am

Today I disasembled the motor to change from star to delta, but until next Monday it will not be welded
As I expected, the coil endings are placed in the standard way that you can connect each one with its closest start, as for industrial 3-phase motors

Image

e-vektor
100 mW
100 mW
Posts: 46
Joined: Sep 22, 2013 10:30 am
Location: Spain

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by e-vektor » Jan 06, 2017 1:25 pm

Anyone can suggest an inverter for 155V (400A-500A) operation? some DIY project or open source or similar. I would not like to have to buy the 144V Curtis now

Harold in CR
1 MW
1 MW
Posts: 1775
Joined: Feb 01, 2010 7:19 pm
Location: Costa Rica

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by Harold in CR » Jan 06, 2017 1:51 pm

Are you aware of tomdb thread Honda IMA on diyelectriccar.com ? It should be good up to 180V at 400 A I believe. Having trouble remembering all the details of various threads.

He is also working on another higher voltage inverter Chevy Volt/Ampera, also on diyelectriccar.com.

Slide on over to that site and look under Controllers if you are not aware of his threads.
Thanks to Justin, the forum is open source and NON-commercialized.

User avatar
parabellum
1 MW
1 MW
Posts: 1963
Joined: Nov 19, 2010 9:55 am
Location: Dominican Republic, north.

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by parabellum » Jan 06, 2017 2:43 pm

e-vektor wrote:I am using a dyno that connects the motor with the brake using a chain. It can have some losses, but they does not seem very high, specially at low speeds which is when the motor has the worst eff. values
Chain is only efficient at low speed, high load conditions, everything else must be included in equation, for any meaningful results.

e-vektor
100 mW
100 mW
Posts: 46
Joined: Sep 22, 2013 10:30 am
Location: Spain

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by e-vektor » Jan 06, 2017 4:39 pm

parabellum wrote:
e-vektor wrote:I am using a dyno that connects the motor with the brake using a chain. It can have some losses, but they does not seem very high, specially at low speeds which is when the motor has the worst eff. values
Chain is only efficient at low speed, high load conditions, everything else must be included in equation, for any meaningful results.
chain is just for the dyno as all parts were available (sprocket in the brake and chain). Dyno can measure the losses

For the motorcycle my idea is either using the original multi-v-belt or a toothed belt, mainly for the noise, but also losses could be important

e-vektor
100 mW
100 mW
Posts: 46
Joined: Sep 22, 2013 10:30 am
Location: Spain

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by e-vektor » Jan 06, 2017 4:52 pm

Harold in CR wrote:Are you aware of tomdb thread Honda IMA on diyelectriccar.com ? It should be good up to 180V at 400 A I believe. Having trouble remembering all the details of various threads.

He is also working on another higher voltage inverter Chevy Volt/Ampera, also on diyelectriccar.com.

Slide on over to that site and look under Controllers if you are not aware of his threads.
No, I am new at this. I am searching some semi-professional solution, as Curtis prices get high for the 144V model, and I already have the 80V model.

Regarding IMA controller, it seems a bit difficult that it matches a different motor, specially if the original motor is PM and the destination one is ACIM
But the idea of using stock parts seems interesting from the point of view of costs, although I think the MCU and software should be written from scratch.
What do you think?

Harold in CR
1 MW
1 MW
Posts: 1775
Joined: Feb 01, 2010 7:19 pm
Location: Costa Rica

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by Harold in CR » Jan 06, 2017 6:46 pm

If you are using the e-assist motor, they are AC induction. I wanted to convert one to PM, but was told it won't work.

No worries about being new at this, I'm green as a gourd myself. :roll: I'm just stumbling along and hope I don't say things that are not correct.

I just read a bit ago, that tomdb has the Chevy/Ampera inverter working well.
Thanks to Justin, the forum is open source and NON-commercialized.

Tomdb
10 W
10 W
Posts: 94
Joined: Apr 03, 2014 7:47 am
Location: Warwickshire

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by Tomdb » Jan 06, 2017 7:12 pm

The idea behind taking an OEM controller is taking just the expensive bits, so the powerstage. Capacitors, Igbts, drivers and current sensors. Then you hook up your own flavor of controller, currently aware of the Lebowski variant for BLDC position sensor less or with hall and the Johannes huebner http://johanneshuebner.com/quickcms/ind ... ter,8.html who can do acim or BLDC but both require position sensing.

I currently have the Honda IMA system worked out to a good degree and indeed also now the Chevy Volt inverter (complete overkill this one for this motor).

But this road will require some electrical knowledge and soldering. Yet the parameters under your own control grow exponentially when you go to a more diy solution.

coleasterling
10 W
10 W
Posts: 98
Joined: Sep 21, 2010 3:37 am

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by coleasterling » Jan 06, 2017 7:51 pm

I'm pretty sure Paul has an ACIM firmware for his control board. You could get Paul to build you a board of his, then Tom has already worked out the rest of controlling a 2nd/3rd gen IMA inverter. Others have done the first gen IMA inverters (round caps vs. the one with the cap as an enclosure) and apparently they are easier to drive than the version Tom and I have.

Harold in CR
1 MW
1 MW
Posts: 1775
Joined: Feb 01, 2010 7:19 pm
Location: Costa Rica

Re: Buick Lacrosse 2012 e-assist moto-alternator

Post by Harold in CR » Jan 06, 2017 8:34 pm

In another thread, tomdb gave me a rough price of materials to build a Honda IMA inverter. These e-assist motors can be had for $100.00 and up, and the price est. was $400.00 or so. Figure $1000.00 for all materials and motor and this MIGHT make a reasonable priced moto conversion possible.

I would be in for trying to build an inverter with some assistance along the way. If e-vector would like to try, that might get a couple more involved, and be a very educational thread for future builders. I'm reasonably certain that the Lebowski chip works with tomdb's inverters. There is a guy (whereswally) that has boards for sale and the Lebowski chip comes programmed, and the newest version can be programmed without sending back. Both can be found on endless-sphere website. I don't know prices yet. Still watching to see if anyone else wants in and maybe order several boards and chips as a group thing. Mine would be sent to USA, Florida.

The motor I have now is a 6 phase brushless and needs 2 controllers, so, added costs to use this motor and, these 6 phase motors are not cheap like the e-assist motor.
Thanks to Justin, the forum is open source and NON-commercialized.

Post Reply