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trooper8
12-26-2006, 03:19 PM
I have a good background in electricity and mechanics but am new to RC.

What are the key features and benefits of a brushless motor in RC?

What does an ESC actually do? Is that a voltage wave chopper?

Thanks

aethertek
12-26-2006, 05:30 PM
What are the key features and benefits of a brushless motor in RC?

What does an ESC actually do? Is that a voltage wave chopper?

No brush electrical losses or wear.
ESC is speed controler, uses PWM (pulse width modulation).

pilotpete2
12-28-2006, 09:56 PM
Hi Trooper8,
As Aethertek noted there is no brush wear or commutator wear. Basically much less maintenance. Another plus to brushless motors is less RF noise, as the arcing of the brushes/commutator has been replaced by electronic commutation performed by the brushless DC controller.
PWM is used both in brushed and brushless controllers as we are dealing with DC. Voltage chopping is used in AC applications such as light dimmers, or to reduce the speed of AC fan motors (only with high slip induction motors).
The second function of a brushless controller is to provide timed switching or commutation to the motor based on the detected back EMF of the motor, in effect the ESC is electrically part of the motor as they run in a closed loop environment. Many folks don't realize that "brushless" motors are in the commutated motor family and operate on the same principals as brushed motors, that's why they have Kv ratings, the higher the voltage, the faster it spins, till failure mode kicks in:D, also we can advance or retard the timing with brushless motors just as in their brushed counterparts (well the better ones, that is).
Welcome to the R/C obses-- er, I mean hobby:cool:
Pete

lshadow2005
12-29-2006, 02:40 AM
What is the reason for advancing or retarding the timing of a brushless or brushed motor ,pluses/minues
I assume you need an ESC that will allow you to adjust the timing ?
Thanks
Bob

ron_van_sommeren
12-29-2006, 01:35 PM
About motors and controllers
Workings of a brushless controller:
http://www.torcman.de/peterslrk/index_eng.html
(http://www.torcman.de/peterslrk/index_eng.html)-> Speedy-BL self made brushless controller
Several diy brushless controller designs and a few design discussions:
www.rcgroups.com/forums/showthread.php?t=140454 (http://www.rcgroups.com/forums/showthread.php?t=140454)
Online course on motors, magnetism and controllers:
www.rcgroups.com/forums/showthread.php?t=200567 (http://www.rcgroups.com/forums/showthread.php?t=200567)
Animations and simulations of brushless motors:
www.rcgroups.com/forums/showthread.php?t=216928 (http://www.rcgroups.com/forums/showthread.php?t=216928)Building your own brushless motors (20Watt-20kWatt)
Brian Mulder's must read motor building articles, will prevent you from asking a lot of questions ;)
www.southernsoaringclub.org.za (http://www.southernsoaringclub.org.za)
-> articles from Southeasters
-> electric motors, part 1-5
Do-it-yourself motor homepages, manuals/tutorials, checks and tests in the first message of this motor builders tips and tricks thread. The checks and tests may save you from frying your controller or motor. Thread is active, bookmark it for future reference and subscribe to it:
http://www.rcgroups.com/forums/showthread.php?t=240993 (sticky thread, at top of subforum)
Peter Rother's bible:
www.torcman.de/index_e.htm (http://www.torcman.de/index_e.htm)
-> know how
-> English version
Ralph Okon's motorbuilder bible:
www.powercroco.de (http://www.powercroco.de)
Don't let the German language deter you, a picture(s) is worth a thousand words, and you can use an online translation tool, e.g. http://babelfish.altavista.comVriendelijke groeten ;) Ron
diy motor building tips & tricks (http://www.rcgroups.com/forums/showthread.php?t=240993)
diy brushless motor discussion group (http://www.yahoogroups.com/group/lrk-torquemax)
Drive Calculator (http://www.yahoogroups.com/group/D-calc/) download & discussion group
int. E fly-in & diy outrunner meet (http://home.hetnet.nl/%7Eronvans/), Aug.26 2007, Nijmegen, the Netherlands

tennistal0n7
03-11-2007, 08:30 PM
ummm, i think brushless is slower and more acrobatic? i think.

ScubaSteve
03-13-2007, 08:44 PM
ummm, i think brushless is slower and more acrobatic? i think.

Nope that made no sense actually. ;)