Thread Number: 86113  /  Tag: Modern Automatic Washers
Large Brushless DC (BLDC) Motors in NA-Market Machines? 		[Down to Last]

automaticwasher.org's exclusive eBay Watch:
scroll >>> for more items --- [As an eBay Partner, eBay may compensate automaticwasher.org if you make a purchase using any link to eBay on this page]
Post# 1106748   2/4/2021 at 14:29 (1,173 days old) by LowEfficiency (Iowa)        

lowefficiency's profile picture
A bit of a different question...

Is anyone aware of any washers/dryers made for the North America markets, that used brushless DC motors in a conventional belt-drive application?

I'm seeing that Samsung seems to like them, for example the "DC93-00316A" washer and "DC31-00184C" dryer motors. But most (or all?) of them are from overseas models.
Some of the smaller motors (pumps, etc) have gone BLDC, but not the big ones.

It seems as though most of the machines for our market changed from single-phase induction motors to variable-speed three-phase induction motors instead, and those few which did go BLDC used the large pancake motors as part of a direct drive system.




Post# 1106795 , Reply# 1   2/4/2021 at 19:46 (1,173 days old) by henene4 (Heidenheim a.d. Brenz (Germany))        
BLDC Vs Inverter

 Since they are both driven pretty much the same and constructed pretty much the same, there really isn't much of a difference.



Main point is if it is an induction based motor or permanent magnet.

Permanent magnet is usually a little more efficient, but getting the same power requires some pretty "expensive" components (the required permanent magnets can get pricey compared to just a squirrel cage rotor).

They both need different control and have different torque/speed characteristics.




The BLDC Vs Inverter thing is just minor definition differences.

A "true" Inverter uses chopped DC to charge a bank of capacitors which in turn create close to a sine wave.
Capacitors are expensive and failure prone.
If you had a true Inverter in any machine, you could just hook up any single phase induction motor and it would run.



As transistors got better and cheaper for that matter, it became a true possibility to just skip the capacitors (for the most part).
By now you can just switch transistors so fast that with very little smoothing you can create close enough to a sine wave that inertia does the rest.
It's a tiny bit less efficient, but barely so.




And since the technology got so close to each other, BLDC and Inverter became intermixed.





It is rare that in the relatively low power and cost sensitive world of appliances you'd find a true sine wave Inverter.
Most boards are just basically a bridge rectifier, a single large cap for the output smoothing as well as a power transistor per phase.
Then a micro processor plus it's support components.
Some filtering and decoupling.




A true sine wave Inverter needs at least one cap per phase.
Plus another cap at least for input smoothing.







What I am more confused about is the mention of a controlled motor in an US dryer?

We do have brushless driven motors in dryers over here.
Usually in highest efficiency models since the motor wattage actually makes up up to 1/5 the entire dryers power consumption (were talking like 550W total draw).

But on a dryer that draws 5kW of power for heating anyways and only runs for like 50min?
I'd be surprised if they ever spend the 50$ or such to save like 40-60W of draw.





On washers I am pretty certain that any washer on the US market that is a front loader with a belt drive uses basically the same driver.
And pretty certain none of them are really what you would consider a true Inverter.

Though really - there is no real difference.
Both a perfectly fine ways of running motors and you won't be really abled to tell the difference.


Forum Index:       Other Forums:                      


Comes to the Rescue!

The Discuss-o-Mat has stopped, buzzer is sounding!!!
If you would like to reply to this thread please log-in...

Discuss-O-MAT Log-In



New Members Click Here To Sign Up.



                     

automaticwasher.org home
Discuss-o-Mat Forums
Vintage Brochures, Service and Owners Manuals
Fun Vintage Washer Ephemera
See It Wash!
Video Downloads
 Audio Downloads
Picture of the Day
Patent of the Day
Photos of our Collections
The Old Aberdeen Farm
Vintage Service Manuals 		Vintage washer/dryer/dishwasher to sell?
Technical/service questions?
Looking for Parts?
Website related questions?
Digital Millennium Copyright Act Policy
Our Privacy Policy