Talk:Brushless DC electric motor

message: There are several parts wrong in this section. either the stator or rotor fields can be commutated, the term "commutator" does not only apply to the brushed commutator, but also applies to the brushless commutator that changes the field in the stator of a brushless DC motor. Note that these changes also need to be made in many accompanying articles. Here are some lay references, there are plenty of academic references as well, but I don't foresee this will be in dispute. https://www.machinedesign.com/automation-iiot/article/21832366/motion-design-101-electronic-commutation, http://fab.cba.mit.edu/classes/961.04/topics/brushless_DC1.pdf, https://buildingenergy.cx-associates.com/understanding-electronically-commutated-motors Skeptonomicon (talk) 16:05, 10 September 2020 (UTC)
replies: text: There is no longer a Brushless DC electric motor#Commutator section but I have reviewed the Brush commutator and Brushless solution sections and no longer see the identified problem. ~Kvng (talk) 18:55, 20 May 2024 (UTC)
thread_title: commutator section

message: "In a BLDC motor, the electromagnets do not move; instead, the permanent magnets rotate and the gamaray remains static."  —Preceding unsigned comment added by Ericg33 (talk • contribs) 08:29, 30 October 2009 (UTC)
thread_title:  Gamaray? 

message: See the large removal in this edit http://en.wikipedia.org/w/index.php?title=Brushless_DC_electric_motor&diff=483426920&oldid=483368233 (the other stuff is tweaks)
Slightly confused section - a BDC motor needs an inverter and control stuff to make it work - that much is clear. I removed the text-book stuff about "first we should consider".
Most of the description appears to be that which should be found in articles on Inverter, or VVVF drive, of Vector drive, or whatever people call them -
There was some specialised unreferenced stuff - eg  "In addition, using a trapezoidal control leaves one leg undriven at all times, allowing for back-EMF-based sensorless feedback." -this needs referencing with context if it is to be in the article.
There were other problematic sentences such as "A motor can be optimized for AC (i.e. vector control) or it can be optimized for DC (i.e., block commutation)" - the issue here is that there is no clue and no article saying what "block commutation" is.. I'm not sure what it is trying to say, and it appears vaguely contradictory with earlier statements. The term "trapezoidal EMF" is also unexplained.
One bit that is not clear enough
::Another very important issue, at least for some applications like automotive vehicles, is the constant power speed ratio of a motor (CPSR). The CPSR has direct impact on needed size of the inverter. Example: A motor with a high CPSR in a vehicle can deliver the desired power (e.g., 40 kW) from 3,000 RPM to 12,000 RPM, while using a 100 A inverter. A motor with low CPSR would need a 400 A inverter in order to do the same.
There is no article CPSR - and the text doesn't currently make that much sense.
Someone else should look at this - also the article makes the assumption that  BDC motors always use a Permanent magnet synchronous motor - as far as I know this is correct  -though contradictory examples will probably exist - the main issue with this is that it might be better to cover the motor science at Permanent magnet synchronous motor and link to that article from the page.Oranjblud (talk) 21:23, 22 March 2012 (UTC)
replies: text: CSPR and inverter no longer appear in the article. ~Kvng (talk) 19:10, 20 May 2024 (UTC)
thread_title: Section on inverters

message: I am not exactly a motor expert so correct please,  but I would understand that the real revolution in creating BLDC motors with incredibly high power to size ratios has come about with the advent of rare earth permanent magnets. The electronics and the rare earth magnets are the two technologies that enable the hi-power density applications such as electric cars, Segways, drone copters, etc, etc. I think an article that fails to mention neodymium/iron/boron alloy magnets leaves a significant gap in the knowledge of the reader.  Here is a typical reference science direct
:neodymium magnets is mentioned in the lead and I have added the suggest ref there. ~Kvng (talk) 19:17, 20 May 2024 (UTC)
thread_title:  Rare earth magnets 

message: "The controller times commutation (hence rpm) and creates current waveforms (hence torque)."
Say What?? Is that even a sentence?
The opening paragraph here needs major rewrite to avoid  use of highly specialized technical jargon.
174.103.146.141 (talk) 01:10, 31 March 2017 (UTC)
thread_title:  too much jargon in opening