Brushless fuel pump and fans?

[mazdamx640]

I found a couple interesting articles on dsports website about brushless motors being used in fuel pumps and cooling fans about how they use much less power and last much longer. I thought about how this could apply to the mpg game. The cooling fans might not apply as much but the fuel pumps on cars are always running and what about using brushless motors for the hvac fan?
I know this falls into the splitting hairs category and may be far from cost effective but when going for maximum efficiency it sounds like a good idea...
http://dsportmag.com/the-tech/educat...-fan-solution/
http://dsportmag.com/the-tech/educat...cs-electrical/

[redpoint5]

How much more costly are we talking, on average?

Brushless is discussed often in the RC community, with the same benefits/drawbacks mentioned.

Yesterday I received a brushless RC helicopter and I heard that the brushed version is $5 cheaper.

I'd be willing to pay more upfront for something that will never need maintenance and be a little more efficient. The starter motor for the ATV is always needing new brushes, which is an additional cost in both materials and time.

As a tangent thought, rare earth permanent magnet motors are more efficient than induction (though I don't know by how much). Tesla uses induction, while many other EVs use permanent magnet. Of course, permanent magnet is more costly.

[Stubby79]

Lets see...you can use PWM on brushed motors too, if you're looking to save a bit of power.

And there's no real need to use rare-earth magnets in small-output motors such as these. Your more common/cheaper magnets, like ceramics, will work fine.

I'm not sure how much longer a brushless would last than a brushed motor as a fuel pump. They last one heck of a long time as it is. Without taking a dead one apart, for all we know it could be the bearings that wear out first. You'd probably also want the control circuitry to be separate and easily replaceable, in case it goes before the actual motor does. There is no control circuitry to be concerned about on a brushed motor.

I like the idea. I just don't know if they will last considerably longer or not.

[oldtamiyaphile]

Switching a HVAC motor to brushless has been on my want list for a long time. A suitable R/C motor and controller shouldn't run more than $100.

No more extra heat in the cabin from the resistor, infinitely adjustable speed and a fair bit of power saved.

[Stubby79]

I doubt you'll get enough torque out of an R/C motor. And, as I said, you can get the speed control and power saving with your current motor by running a PWM control to it (and bypassing the resistors).

I paid about $5 for a PWM circuit off ebay that's good up to 90vdc and 15 amps. It's smaller than a deck of cards.

BTW, I think some of the return-less fuel systems are already being controlled by PWM directly from the ECU.

[mazdamx640]

Originally Posted by Stubby79

I doubt you'll get enough torque out of an R/C motor. And, as I said, you can get the speed control and power saving with your current motor by running a PWM control to it (and bypassing the resistors).

I paid about $5 for a PWM circuit off ebay that's good up to 90vdc and 15 amps. It's smaller than a deck of cards.

BTW, I think some of the return-less fuel systems are already being controlled by PWM directly from the ECU.

That sounds like a good idea I might try it with my truck is this like what you were talking about?
https://m.ebay.com/itm/12V-24V-48V-2...4AAOSw0O5aHjCs

[gumby79]

The difference between BLDC and Brushed is about 2 fold mor run time on my RC rock crawler. 30min Vs 2hr on a 5ah 37wh battery.

[spacemanspif]

Originally Posted by Stubby79

BTW, I think some of the return-less fuel systems are already being controlled by PWM directly from the ECU.

True statement. Cooling fans too, I believe. Does a PWM care if the motor is brushed or brushless?