Modern Appliance Motor drives

[shieldcracker]

Hello,

This is my first post! I have been looking around  for the last hour and I allready love this forum.
Nowadays many AC and appliance mfg. are shifting to inverter variable speed drives to provide different motor output speeds. This technology is here to stay and I want to gain deeper insight on it. Does anyone know were to find downloads or good reference books that provide in depth treatment of this subject. I have downloaded some washing machine manuals as a starting point although I expect the info there to be quite terse, but it will do for now.

Thanks

[JWWebster]

I think that would be pretty dumb to put in variable speed crappy motors

[Repair-man]

So, you want some insight as to the revolution of energy-saving motor controlling?

here's a  few examples:

http://www.industrialcontroldesignline.com/howto/207601012

http://www2.electronicproducts.com/Variable-speed_motion_for_appliances-article-irf-aug2006-html.aspx

http://www.techonline.com/learning/techpaper/193103241

http://users.utcluj.ro/~szabol/Papers/FROSysConf2002.pdf

[shieldcracker]

I think that would be pretty dumb to put in variable speed crappy motors

You might not like it but I assure they are here to stay. In general for multi speed applications or situations that impose a variable load on a motor there is no better alternative in terms of performace, control characteristics and energy savings. Within the next 6 years most (all) appliances manufactured will include a variable speed motors, just remember what happened to carburetors once computer controlled fuel injection became economically feasible.

I advise everyone out there that wishes to remain at the top of the game to get involved with this technology, sure it is shrouded in electronics which makes diagnostics a bit more complicated and a mystery  but there is the challenge.

[JWWebster]

well you gonna need a mother board to run the variable speeds on them motors It will of course have a 3 phaze dc inverter to run said fan. That is rediculas. As far as fuel injection you need a computer board for that plus a dang hi output electric fuel pump inside the tank and a larger alternater to accomodate all that mess. A 2 barrell carb and slant 6 dodge
Is what I drive now and when the crappy electronics dies on it I will install  a distributer with points in there.

[Penguin45]

We've got loads of 3 phase front loaders in the UK now. The great majority use under-engineered electronics which blow up on a whimsey. Some higher end stuff is actually very good, but, it's got nothing to do with energy usage - it's about silence. No carbon brush whine to annoy the customer........

Penguin45.

[JWWebster]

P45 I wish I had yore knowledge son. You are bad to the bone. I'd love to tip a few with you if the occasion ever set itself my brother.

[shieldcracker]

P45

In general the actions of a manufacturer are influenced by 3 major forces.

1. Safety: The mfg's appliance must be inherently safe and not endanger the user or his property.
2. Law: Mfg must comply with government regulation, that is the reason you don't see new appliances  with R-12 anymore or refrigerators with 1.5" insulation etc... 
3. Economics: If a mfg can get away with a cheaper substitute to get its job done he will go that way.

Factoring out the safety issue, By using  3-ph motors with VFD the maker of the appliance has
A) Provided a more energy efficient unit to meet requirements set  by the law
B) Has reduced the cost by using a smaller motor.
Why else they would shift away from the standard multi speed induction motor?

While I agree that many of the electronics to drive the inverter are cheap and troublesome I understand that they are here to stay.

[RegUS_PatOff]

LG (and some other Variable Speed, Reversible, Direct Drive) Washers:

NO Transmision, Brakes, Clutches, Belts, Gears, Drive Block, etc ...

[Penguin45]

Interesting point of view, SC. I would suggest that in the UK (can't speak for the NA market), there is only one driver - price. If it'll go through BEAB (Britsish Electrical Approval Board) testing and last 367 days (just in case there's a Leap Year) to cover the guarantee, they'll sell it. Quality in the mass market has been tossed out of the window over here. People seem happy to buy budget carp and accept that the service life is between 2 + 3 years before replacement.

The point is that Laundry is a saturated market. There are now no new customers, so there is only replacement. To keep the factories running at their previous levels, you can:

1) Reduce production. Ain't going to happen, is it?
2) Build rubbish that looks good and falls to bits early. Now you're talking..... Suck 'em in with the bells, whistles and options. "Sorry it didn't last 10 years, Madam, here's a discount voucher towards your next ----- (insert Name here) product.

It's an absolute disgrace in Europe. This has been led by the Indesit Company AND, they've got away with it. People accept that machines "Don't last like they used to" and "My last one did 15 years".

No doubt this is coming your way too.

Minor rant over, peace to all.

Penguin45.