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Pdelcast
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12.07.2017, 06:56 PM

Quote:
Originally Posted by maxxximatoze View Post
For those who are interested (if any) in electrical parameters from this new motor, I've done some meseaures on my brand new 1515 1Y sensored (bought from amain, hope that it's not a fake !)

The motor is on my desk with no cooling and no pinion, and it is new. The esc is a brand new castle MMX (also from amain). These measures where done from a regulated power supply to get precise input voltage, current and wattage (dps3005 verified by myself for its precision readings) and a little oscilloscope to get the precise wave form on motor phases (to check the full throttle) and the precise frenquency to determine the rpm (freq/2x60 because of 2 poles pairs). The I0 is the current from the PSU minus the idle current consume by the esc (which is variyng between 150mA@8V to 75mA@24V). The motor power loss is then the PSU voltage by the motor I0. I don't use MMX logging to get I0 current because it not precise enough on such low current.


At 8V I0=2A power=16W rpm=17760 and kv=2220 (maxeff=93.1% at 56.6A)
At 10V I0=2.2A power=22W rpm=22140 and kv=2214 (maxeff=93.5% at 66.3A)
At 12V I0=2.4A power=29W rpm=26640 and kv=2220 (maxeff=93.8% at 75.9A)
At 16V I0=3.0A power=48W rpm=35460 and kv=2216 (maxeff=94.0% at 98.0A)
At 24V I0=4.0A power=96W rpm=53250 and kv=2219 (maxeff=94.3% at 138.6A)

I will do the measure at 20V soon.

The MMX logging of RPM is 3.6-3.7% more than my measures. Not too bad. Maybe due to it's clock without crystal oscillator. Dont' really know.

The motor heats up very slowly at 8V (takes several minutes to reach 50°C) but it's a different story at 24V, it's more a matter of seconds before it reach 50°C and before you can't hold it in your hand. And it is with no work done, just the losses. It's always a good idea to have a good cooling solution.

The next step is to mesaure precisly the Rm of each phase to see if the motor is well around 5 milliohms.

Question for patrick, are you sure your measure was at 24V ? Because your result seems very far from what I get (2.7A versus 4.0A).
Were you running sensored or sensorless? What phase advance were you using?

Note that you will see higher IO at higher phase advance.

Thanks!

Patrick


Patrick del Castillo
President, Principle Engineer
Castle Creations
   
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