Adding sensors to a Astro 3210 motor

[Burtie]

Hmmm, -ebike controller with adjustable timing tables, sounds like a nice idea!

Anyone out there fancy a PIC / Infineon firmware project?? could integrate the D-Y switch in the FET output stage as well

Hell, I might even have a crack at it one day, but it wont be quick!

As an interim solution I wondered about more slots in the plate for a second hall group to run delta. Could parallel the outputs of the two hall groups and just turn on power the group that was required

Burtie.

[Burtie]

Very awesome Burtie! Are kits for other Astro owners in the future?

Thanks for all,
Kevo

Hi kevo,
Yes I will look into the cost of getting a number of these discs and plates made up soon, as a sort of kit

Burtie

[Ypedal]

Put me down for one !

[johnrobholmes]

Same here, I want!

[Scorefield]

Put me down for one !

Same here, I want!

Sign me up for one, please.

[matt_in_mtl]

Hmmm, -ebike controller with adjustable timing tables, sounds like a nice idea!

Anyone out there fancy a PIC / Infineon firmware project??

You mean something like this?
http://scolton.blogspot.com/2010/01/3ph-duo-wrap-up-part-1-field-oriented.html
A very interesting read, he is going a couple steps further too though.

Very cool results Burtie, very cool!

-Matt

[Burtie]

Good find Matt,

We need that guy here with us on the sphere!



On the subject of cooling, -If you can't fix the cause, then just treat the symptoms:

How about these fins to dissipate the heat generated by those recirculating currents

They are the ones that Cyclone sell to keep their heat problems in check. Almost perfect fit on the astro.

Astro fins.jpg (101.84 KiB) Viewed 467 times

[kevo]

Burtie,
You are another hero in the Endless-Sphere among us lesser mortals!
Definitely sign me up for your Hall Sensor holder when they become available.

Regarding using Cyclone heat sinks for Astros, doesn't Cyclone only sell these with their Cyclone kits?
Is there an alternative way to just buy the heat sinks for us Astro folks?

-Kevo

[dbaker]

Burtie,

Great work! I am waiting for a 3220 to arrive and am interested in a kit. I already got the Hall sensors.

Dave

[Grinhill]

Is there an alternative way to just buy the heat sinks for us Astro folks?

-Kevo

Hey Kevo, Recumpence made some heatsinks for Astros a while back, send him a pm, he may still have some.

[etard]

Burtie, you are the man!! You didn't pop your head in on this video, we missed your smiley face. This is great work, will you be designing a HXT sensor plate? Put me down for one if so.

Shane Colton is one smart dude, I followed his progress from two year ago, I invited him on here, cause his work parrallels everything that goes on here, but I think he is more tuned in on the robot front.

I think if Burtie, Fechter, Gary, Nicobie, MWKeefer, and Doctorbass got together (I know I'm missing a board genius or 20, our talent pool is DEEP, oh Bigmoose, see ) together on this delta\wye switchboard you guys could crush it out in no time. Sorry if I volunteered anybody that might be up to thier ears in other projects ...cough BMS...cough.

Another thought I had was, what if we could contact an EE Professor of some renowned school to get his students to solve our problems, we could get these things done much quicker, maybe we could just setup a preorder system to pay for components? I am quite ignorant on what these students actually do at the higher levels, so forgive me.

[AussieJester]

I am quite ignorant on what these students actually do at the higher levels, so forgive me.

I'm not I seen a heap of American teen College based movies, they have kick ass parties etard, they call them "keggers" and all the chicks are drop dead gorgeous with fake breastassess... You probably will be surprised to learn also, they aren't actually in class much at all, leaving all study to the night before exams... while of course consuming copious amounts of beer and pizza resulting in waking up late for the exam start time

KiM

[Jeremy Harris]

If you want these finned can-type heatsinks, then take a look at those sold as oil filter coolers, like these: http://www.carbuildersolutions.co.uk/oi ... cooler.htm

There are almost certainly cheaper places to buy them than that link, it was just the first that popped up when I googled. I've used these on aircraft oil filters and found that they made an appreciable difference to oil temperature. I can't see why they wouldn't work just the same on a motor, it would be just a matter of finding one the right size.

On the topic of delta/wye wiring and losses, then what Burtie has found mirrors the stuff I found out a year or so ago when converting outrunners from delta to wye. The thread is around here somewhere, but I didn't make much of the higher Io in delta, as I run my motors exclusively in wye.

Jeremy

[Dee Jay]

I seen a heap of American teen College based movies, they have kick ass parties etard, they call them "keggers" and all the chicks are drop dead gorgeous with fake breastassess...

Keggers aren't really my kind of movies..

..more of a frock wearing Judy Garland movies fan *rim shot* but I gave the "The Hangover" a chance and I gotta admit

I

Laughed

My

Ass

Off

[damcard]

If you want these finned can-type heatsinks, then take a look at those sold as oil filter coolers, like these: http://www.carbuildersolutions.co.uk/oi ... cooler.htm

Nice find. This should be added to a resource page. -David

[12p3phPMDC]

Burtie,

I was wondering about the back EMF generated by the Astro with distributed windings.

Not trying to be a bother, but, Would it be too much trouble to ask if you would to spin the Astro with a drill and scope/monitor
the phase leads to see what the waveform looks like.

It appears to be a double hump sinuisoid from watching your video....but seperating the controller waveforms would help see the raw BEMF.

[Burtie]

OK,
I connected the motor to the 'scope like this:

Scope connection

Raw connections.jpg (132.68 KiB) Viewed 730 times

Spun it up with the drill, to see this:
( I know it starts a bit scary, but it gets better )

http://www.youtube.com/watch?v=I_fGepS3TBI



It does indeed appear to be a double hump sinusoid as you suspected.

Burtie.

[AussieJester]

:: waves back :: hiya Burtie

KiM

[12p3phPMDC]

I didn't expect such a quick reply!!!
You're a gentlemen Burtie, much obliged.
Thanks for the virtual lab!

Yea, you kind of look like the ominous ghost in the scope at first....

It looks like a hybrid trapezoid double hump sine waveform. Cool.

I would guess that if there were more poles and more distribution to the windings that the wave would tend to be more sinusoidal.

[liveforphysics]

I would guess that if there were more poles and more distribution to the windings that the wave would tend to be more sinusoidal.

I think the humps are caused by sharing poles, not lessened by it. I've only ever seen clean sinewaves from motors that wrap 1 pole at a time.

[12p3phPMDC]

I would guess that if there were more poles and more distribution to the windings that the wave would tend to be more sinusoidal.

I think the humps are caused by sharing poles, not lessened by it. I've only ever seen clean sinewaves from motors that wrap 1 pole at a time.

Yea, that actually makes more sense. Due to each pole having an individual contribution to the BEMF. thanks for that correction

From looking at the pics the windings are distributed across three poles. So how would that generate the double hump?
Would the voltage peak when a magnet is centered in the slot? 3 poles, 2 slots = double hump?

I wonder how the BEMF will change when the motor is actually terminated in Y or Delta.

Burtie seems to have isolated a single phase and shown the BEMF from it. That has to be the simplest BEMF waveform because you'll have less interactions between phases.
And no circulating currents are possible in that config. Any thoughts?

[Tiberius]

It can't be that simple. Like Luke, I've only ever seen sine waves out of the motors I've tried this with. If you take any combination of sine waves at the same frequency, you always get another sine wave.

The waveform Burtie showed looks as if it has a 3rd harmonic in there. You can't generate that shape by adding staggered sine waves.

I suppose its possible that the magnets are arranged so that the flux through the poles doesn't vary sinusoidally.

Nick

[12p3phPMDC]

Tiberius,

True....

Since Burtie had the phases isolated, where is the third harmonic coming from? The magnetic circuit I suppose?

[Burtie]

Burtie wrote:
There seemed to be no acceptable compromise between the delta and wye hall group positioning that would work well for both configurations.

I am not so sure this is true now...

The other day, I took apart the wiring between the motor and the controller, so that I could insert a Delta-Wye switching unit (D-Y switch shown here
viewtopic.php?f=28&t=15344#p249091 )

When I re-wired the system, I ran through the same test as before, looking for the optimum timing positions for the two modes. To my supprise I found that the angle between the two optimum positions was now only about 4 degrees, where previously it had been 12 degrees.
Because the angle is small, it means that there is a good position that works well for both modes.

I am not sure why the picture has changed . I used a different sequence of phase wiring than before for the delta mode, which in turn meant i needed a different hall sensor sequence, which I found by trial and error. I now find that the Delta timing is at a point 4 deg retarded in relation to the Wye timing, whereas previously it was 12 deg advanced.

errrr?

Burtie

[johnrobholmes]

Did you terminate your phase ends differently? I have a sneaking assumption that you may have had one phase wired in backwards from the rest on the first test. This would be like having all blue ends together for Wye in one instance, but having two blue and one black end together for another Wye termination. Delta has the same possibility.