Where are these amps coming from?????

blisspacket

100 W
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Apr 17, 2009
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StAugustine FL
YOu can see the layout. Those are Aeolian 6374 motors, 2000watt controllers, 48volts from Nissan Leaf; two lowtech blowers to cool the motors.

The motors are sensored with equals0designs hall sensors. All the following numbers are no-load: At 300 rpm I'm drawing .4 amps ; at 3200rpm it's at 6amps; at 3700 it jumps to 15 amps; at 4000 rpm 19 amps; at 4300 25 amps. At 4400 SMOKE!!!!.

The motors are 170kv and should wind up to 6000 rpm.

Why so many amps to spin no-load? If the sensors are outta sync, how might I sync them? Thanks in advance....
 

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I can't tell, but assume that the motors run props.

I'm not a aeronautical or any other type of engineer, but to my non-engineer brain, I would think that the power requirements increase with some exponential factor with respect to rpm as you are trying to overcome air or water drag.

But on the other side, a motor with 170kV run at 48V should try to spin at 8160. Can you test the hall sensors for functionality?
 
I'm not nautically inclined, but that project looks cool as hell.

Maybe try decoupling the outrunner from the prop shaft and check no load amps again if you haven't already?

PS thanks for the link to equals zero designs, I'm adding that to my bookmarks.
 
thanks cal3thousand, gregory: yes, I tested the sensors for functionality. Equals 0 Designs gave me the basic instructions on how to do that; they sent a spare sensor, which I haven't had to use; all 6, for two motors, worked fine. I sheared the helix coupling in the test run, so those numbers are power consumed just in spinning the motor, nothing more. I'm new at this, and if the motor is running, that seems just fine and for what more could you axe? Well, I could ask for fewer amps consumed, and especially no smoke at 4000+ rpm. I dread the prospect of examining rpm and amps drawn with every combination of phase possible, AND every combination of Hall sensor possible. I think that's 27 different setups???
 
Where's the smoke coming from? I take it the motors. Zero designs had the workup sheet to make sure the hall sensors are correct. I would try that first. Sounds like a pain and one of the reasons I haven't done it yet. Plus the cost was a bit for something I was going to just try out to see how well it worked. Curiosity has killed my pocketbook. Have to let us know how it goes with them.

What props are you using with that setup? I just got the torqeedo prop mounted on my 6364 motor, but have yet to get it on the water. Hope to do that sometime this week.
 
I haven't tried but maybe an ebike tester could be used to check which phase/hall is activated as you spin the motor? Not sure.
 
I am wondering why you are not using regular sensorless ESC's to run these motors? Surely adding halls is complicating the matter.
 
Yes, dirkdigger, there is a full description
http://e0designs.com/documentation/finding-motor-phase-sensor-combinations/
and I thought that once running I was good to go; apparently there's more fine tuning, which I dread, but better to get with that program than to burn the motors.
Props I made out of 1/4 aluminum; more suitable to high speed than the torqeedoes, which have a planetary gearbox for low low rpm. Definitely I'm gambling that there's enough thrust at higher rpm.... Goal is complete a 25 mile Wye River Marathon. That's why I'm trying the sensored approach; it's easy to burn out an unsensored esc, Tench. I thought the Castle Creations Hydra 200 would work, but they're designed for inrunners and really high rpm.
Thanks Gregory, I'll study John in CR's link you provided.
 
I completed a full range of the combination possibilities for the phase wires. One of the mysteries is the controller has a "selflearning" feature: you plug two wires together and somehow that provides feedback to the controller and helps align sensors and phases. Anyway, I did NOT use that feature in trying all the phase combos.

I wound up with the best performance when the phase wires were hooked up as in my first report. The readings are much better this time, however. For 3k rpm, 1 amp; 4k rpm, 2.4 amp. These numbers are approx. the same for both fwd and rev. Advancing or retarding the Hall sensor quadrant does make a big difference: at 3k in Fwd, 1 amp draw changes to 4.3 when the Halls are retarded 1/8".

The amps drawn seemed reasonable and I've chosen (for the moment) NOT to try to look at all the combinations of the 3 Hall sensors.

Finally, the big downer: trying to dial past 4k rpm gives lower speed advances for greater increments of dial turning. I got to 4400 and the controller powered off, in one instance. Again, this is a 6374 outrunner, 170kv, with 47 volts pushing. I don't understand why the controller is limiting rpm. Can I measure the phase voltage between any two of the three wires and learn how many volts are going to the motor at 3 or 4K?? Will the voltmeter mess with the phase alternations?

I have a beater ESC that's limited to 24v, and tried it on the motor; 2000 rpm took 6 amps, so I'm thinking the ev controller is definitelythe more efficient. If I have to configure my props to run at a lower rpm, that should be possible.

Your comments and suggestions are appreciated. Thanks in advance...
 
UPDATE: I've been able to reduce amps to about 7 when running to 3400 rpm. That's the max rpm. At 1200 rpm it's only drawing .6 amps. I have tested the halls for functionality: each throws out a varying voltage from .02 to 4.8 as I hand turn the rotor. I've been stymied to get the motor to run under load: after a minute or less it loses sync. The motor just sits and quivers.
The Hall Sensor arrangement that I've added with EqualsZeroDesigns engineering is a nice addition, and allows the fine tuning. BUT BUT BUT: the controller gets flibberjibet with a load. The Chinese vendor has been patient and helpful in advancing suggestions, but the last suggestion is Impossible: they'd like me to mount the Halls INTERNALLY. I just can't see it.

So for those out there contemplating BLDC's, here are the questions that pertain to the functional operation of the controller: is it an inrunner or outrunner? (Castle Creations has Hydra ESC's that are engineered for INrunners) . Is it sensored or unsensored? (From what I read here on the forum, sensored requires less of the controller, and Halls introduces more external wires into the mix, which require care, etc) . And now also, does the controller work only with internal hall sensors. Are there experts out there who can correct/explain this last?
 
You might try experimenting with the hall bracket different distances from the motor. I seem to remember guys having some success with that. Halls sense a change in magnetic polarity. Sensing from outside the motor means you're sensing the flux going from the magnets through the magnet backing ring that is outer shell of the rotor. Do you know of anyone with success using that specific motor with external halls? Could it's rotor shell be thicker, so less magnetic flux gets through than the Turnigy's?

The high rpm issue may be a limitation of the controller at high electrical rpm. Get one going with a prop in the water or some other load at low rpm first.

What about phase angle of the halls vs what the controller expects? 60° or 120°
 
Thanks John in CR for those notes. I do think the e0designs sensor mounting boards are the proper fit for the motor, which is the Aeolian 6374. I've no idea if the geometry of the boards coordinates/meshes with the perceptions of the controller. I do know that when I put the props in the water under load, and a slowly graduated one at that, the motor goes into tremor mode before it even gets to 1500 rpm.

I have sent the controllers back to China, and have a couple HV ESC's from Castle Creations. Yes, the motors spin no load right up to 6200 ( I stopped there, wuss that Iyam) with the CC ESC's. I'm delighted to be with Castle Creations products and their excellent support. I'll report next week how the CC ESC's work under load. I've removed the e0designs boards, and will go unsensored for a while.

AND there's a brushed DC motor (two actually) that I'll configure to the Thai Panga riverboat drive style, just in case all this wonderfully hi-tech stuff doesn't pan out...
 
What diameter and pitch are the props? Those little motors will need little props to turn thousands of rpm. I can't tell much about the boat except that it appears substantial, are you wanting to get up on plane?
 
if everything comes together, yes I'd like to get on plane. these are surface piercing mode props, ain't nobody builds them so I have my crude construction, but so far electronics have stalled that development. They're about 7" diameter. Sorry, foto talents are nil, haven't learned/remembered how to fit to allowed size 512kb
 
Surface piercing...sounds great, but the problem is the double load while the props are fully submerged trying to get on plane. I think you have lots and lots of prop testing ahead of you. I value silence with electrics, so my eboats will be much easier....bigger silent motors with more than enough start up torque to swing as large a submerged prop as I can comfortably fit.
 
you should only be getting around 2.8A at 48v no load... if you are getting more amps than that @ 48v then the timing is not right.

also what John from CR said about the type of controllers.. what controllers are they ? the only controllers that I have found that work at the higher rpm are the infineons .. but thing start going bad with other controllers between 4 -5 k rpm so I dont think this is/was your problem ( yet ) . fine tuning of the halls is a must before winding the throttle right up as currents get very high very quick if not set up right. you should have no more than around 3.5A ( i have managed to get it as low as 2.2A )at full beans @ 48v no load if its higher then the timing is wrong.

i have run this size mot0r upto 4kw using sensors and a hot rodded 6fet infineon controller
 
I think elsewhere on ES I posted the demise of this project. I'll summarize here too.
I did away with the sensored controllers, tried some 120 amp sensorless units, and managed to set fire to one controller and motor. Yes, I was being judicious, cranking in low amps. Anyway I put the fire out readily, rowed ashore. Made a few changes to the stbd setup, and again judicious low amps, again fire in the controller, but perhaps the motor survived.

I put a Torqeedo outboard on the boat, judicious 47 low amps, got 7 mph right away. Yes, a totally differnt combo with a geared outrunner, but I'm still mightily turned off by the outrunner/esc approach.

Down the line I'll try a brushed DC motor running a straight shaft to direct drive a prop, but for the moment I'm broke and disgusted.

I have a Cruise R Torqeedo on a larger boat (15 feet, 6.5' beam), and can get 10.5 mph with 200 lbs of batteries, 200lbs of me, probably 300 lbs of boat. I think a surface piercing direct drive could do better, but It'l be a day or two before I can prove it.
 
Sorry to hear about your continuing problems. It still sounds like primarily a prop issue. Your effective gearing is way too high. It's like removing the gearbox from your Torqueedo and running it direct drive without drastically reducing the prop size.
 
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