Model 3 cheaper to buy than BMW 3 series.

[footeab@yahoo.com + 2,129]

4 hours ago, 0R0 said:

Any idea what the logic was about the choice of AC motor vs. DC? Is it a torque issue?

Efficiency.  Generally speaking: AC motors can be up TO (92%) while DC generally speaking hit 85%. 

DC motors are NOT as efficient.  Likewise if you want HIGH variability, then AC high frequency motors are king.  .... Until the armature breaks down to said high frequency and current. 

Torque depends on so many physical constraints as to not bother as being a topic.  Usually packaging of said motor and efficiency are far more relevant. 

[Ward Smith + 6,615]

8 minutes ago, footeab@yahoo.com said:

Efficiency.  Generally speaking: AC motors can be up TO (92%) while DC generally speaking hit 85%. 

DC motors are NOT as efficient.  Likewise if you want HIGH variability, then AC high frequency motors are king.  .... Until the armature breaks down to said high frequency and current. 

Torque depends on so many physical constraints as to not bother as being a topic.  Usually packaging of said motor and efficiency are far more relevant. 

You're not talking about brushless DC motors but old fashioned brush DC motors. There are BLDC motors that have achieved 98% efficiency. 

Some light reading for you

Interested in what @Jan van Eck knows about this, since he builds electric bikes with I assume BLDC motors. 

Edited May 31, 2020 by Ward Smith
Added invite

[footeab@yahoo.com + 2,129]

51 minutes ago, Ward Smith said:

You're not talking about brushless DC motors but old fashioned brush DC motors. There are BLDC motors that have achieved 98% efficiency. 

Some light reading for you

Interested in what @Jan van Eck knows about this, since he builds electric bikes with I assume BLDC motors. 

98 eff... what bollocks.  Maybe in a micro device(they have possibilities) And thanks for the overview reading.  Ah nothing like a refresher course in basic electrical motor design(not exactly something one does all the time for most people)

If 98% efficient, Every Hydro dam, coal station, nuclear plant, Gas plant, etc etc etc would be replacing ASAP.  Everyone and their mother would be beating the door down of anyone who could build them such a miracle!  Every motor in existence would be switched out  Yesterday if this were true. Their company would blow away GE, Siemens, etc. 

Same with every wind turbine and wind turbines have the gigantic volume like hydro dams to make gigantic high eff motors unlike in a car.  Wind turbine generator efficiency, using permanent magnets is roughly the EXACT same as their synchronous generator contemporaries but without GEAR BOXES.  Last I knew, they were still LESS efficient than their Gear box, synchronous motor friends, but were cheaper, easier to operate which is a gigantic +++ when pretending to do maintenance on something a hundred meters off the ground.  This is a giant deal for wind turbines as the #1 or #2 failure by every single wind turbine design was/is the gear box and or main thrust bearing and this before the cost of the gearbox is added. 

Gets back to packaging and why I ignored them.   Works on small motors, but to make a 200HP brushless motor it would be GIGANTIC, since it is based on the PERMANENT, non variable size of said magnets and their magnetic fields.  They are only as efficient as the strength of the permanent magnets and their magnetic fields.  Now give me some superconducting magnets and OH YEA!  Efficiency is tied directly to the magnetic fields. 

EDIT: 200HP and PMDC... I have not calced that power level on the Neodynium magnets, but I have to wonder where their threshold is.  Obviously the PM's work wonderfully up to  their maximum magnetic field, but after that you must make motor BIGGER to sustain the flux.  Flux density maximum is truly hard fixed unlike in AC motors which can go over, but do not like it. 

Portscap: https://www.portescap.com/en/solutions/motor-efficiency they claim 90% using Neodynium(standard claim)

TESLA: https://www.tesla.com/blog/induction-versus-dc-brushless-motors Makes claim of no more than 85% for induction(standard claim), and only barely higher for BLDC

PS: My 92% maybe 93% in some cases is for synchronous motors only. 

Edited May 31, 2020 by footeab@yahoo.com

[Ward Smith + 6,615]

58 minutes ago, footeab@yahoo.com said:

98 eff... what bollocks.  Maybe in a micro device(they have possibilities) And thanks for the overview reading.  Ah nothing like a refresher course in basic electrical motor design(not exactly something one does all the time for most people)

If 98% efficient, Every Hydro dam, coal station, nuclear plant, Gas plant, etc etc etc would be replacing ASAP.  Everyone and their mother would be beating the door down of anyone who could build them such a miracle!  Every motor in existence would be switched out  Yesterday if this were true. Their company would blow away GE, Siemens, etc. 

Same with every wind turbine and wind turbines have the gigantic volume like hydro dams to make gigantic high eff motors unlike in a car.  Wind turbine generator efficiency, using permanent magnets is roughly the EXACT same as their synchronous generator contemporaries but without GEAR BOXES.  Last I knew, they were still LESS efficient than their Gear box, synchronous motor friends, but were cheaper, easier to operate which is a gigantic +++ when pretending to do maintenance on something a hundred meters off the ground.  This is a giant deal for wind turbines as the #1 or #2 failure by every single wind turbine design was/is the gear box and or main thrust bearing and this before the cost of the gearbox is added. 

Gets back to packaging and why I ignored them.   Works on small motors, but to make a 200HP brushless motor it would be GIGANTIC, since it is based on the PERMANENT, non variable size of said magnets and their magnetic fields.  They are only as efficient as the strength of the permanent magnets and their magnetic fields.  Now give me some superconducting magnets and OH YEA!  Efficiency is tied directly to the magnetic fields. 

EDIT: 200HP and PMDC... I have not calced that power level on the Neodynium magnets, but I have to wonder where their threshold is.  Obviously the PM's work wonderfully up to  their maximum magnetic field, but after that you must make motor BIGGER to sustain the flux.  Flux density maximum is truly hard fixed unlike in AC motors which can go over, but do not like it. 

Portscap: https://www.portescap.com/en/solutions/motor-efficiency they claim 90% using Neodynium(standard claim)

TESLA: https://www.tesla.com/blog/induction-versus-dc-brushless-motors Makes claim of no more than 85% for induction(standard claim), and only barely higher for BLDC

PS: My 92% maybe 93% in some cases is for synchronous motors only. 

Go to page 34 in this link, wish I could direct you to the article but the site isn't setup that way. Talks about the workaround to your wind power limitation. 

I'll come back with some efficiency links. 

Dated but good background

2012 IEEE spectrum

2014 Texas instruments

Yes, 98% in a Micro motor used in a quadcopter. Not saying that's achievable in a car… yet. Who knows what tomorrow and billions in research could accomplish? The problem as you well know is the current. But yeah, I'm not solving the problem in a message box on a forum.  

Edited May 31, 2020 by Ward Smith
Added promised links

[Ward Smith + 6,615]

30 minutes ago, Ward Smith said:

Portscap: https://www.portescap.com/en/solutions/motor-efficiency they claim 90% using Neodynium(standard claim)

Quote

Portescap motors are designed to achieve up to 90% efficiency. Powerful neodymium magnets and enhanced magnetic circuit design enable our motors to reach stronger electro-magnetic flux, reducing electromagnetic losses. Portescap continues to innovate electro-magnetic design and coil technologies (e.g. coreless coils) that require low start-up voltage and consume minimum current. Friction is reduced and brush dc motor efficiency is improved by low-resistance commutators and collectors in brush DC motors. Our advanced design allows us to build motors with closer tolerances, narrowing the air gap between the rotor and the stator and resulting in less energy input per unit of torque output.

Not brushless but impressive to get 90% efficiency using brushed motors. Makes you wonder what they could do with BLDC? They seem to sell them but I'm not going to wander all over their crummy site design to find them. 

[footeab@yahoo.com + 2,129]

1 hour ago, Ward Smith said:

Go to page 34 in this link, wish I could direct you to the article but the site isn't setup that way. Talks about the workaround to your wind power limitation. 

I'll come back with some efficiency links. 

Dated but good background

2012 IEEE spectrum

2014 Texas instruments

Yes, 98% in a Micro motor

1st link: Yea, but the efficiency.  Of course the difference here is ability to make something work at all.  When I was working wind, we never even considered it as we were looking primarily at tower and blade cost.  Personally I think they are still making their blades wrong for low $$$.  True, my design would not look as good, but man would they have been much cheaper.  Slight icing problem though.  Here their auto transmission .... it all comes down to cost.  Frankly how they are erecting wind turbines is stupid IMO.  All we have to do is look how a crane is erected and why the Hell are we not doing so on wind turbines???  Would make transport of blades vastly cheaper as well.  I understood when the wind turbines were small, but they are literally 10X larger now, yet their building practices have NOT CHANGED.  It is beyond stupid.  Good find on that article by the way.  Thought they were going to be talking about hydraulic swash plates and bearings for converting thrust into power.  😀  It is not as if the tower is not already subject to cyclic fatigue loads.  Heck if done right, could probably cancel out the cyclic load while generating power as well through the main bearing.  All comes down to $$$. 

2nd link shows 90% efficient Brushless DC.  Ok.  We know.  Maybe you read the inverter eff at 95%?

3rd link shows: ???  A vacuum cleaner for BLDC.... Yes, everyone wants small BLDC in Everything as they are vastly superior to induction or shunt.  Random thought yesterday when mixing cookie dough and the mixer literally almost died because I was mixing a triple batch of gingerbread cookies: I would love a Brushless AC powered kitchen aid mixer.  😀

[markslawson + 1,042]

23 hours ago, Jay McKinsey said:

You will be able to drive out to the beach parking lot and go for a swim while your car waits to be notified that a charging stall is about to open up, it will then drive itself to the stall and wireless charge. When it is full it will drive to a parking place to make room for the next car that needs charging.

Jay, that's great! You should go in for science fiction writing. I'm impressed. But is it SF or fantasy? Why wouldn't the BMW 3 previously mentioned do all those things - except that it wouldn't have to? It could take itself to the petrol/gas station every other week or so when it needs more fuel, and spend a fraction of the time there that any EV spends in recharging . No need to mess around with charging stations, assuming they are ever built in sufficient quantity to handle the immense additional numbers. The fueling infrastructure already exists and works quite well. Anyway, thanks for that - most amusing - but it is time to move on..   

[Jay McKinsey + 1,489]

44 minutes ago, markslawson said:

Jay, that's great! You should go in for science fiction writing. I'm impressed. But is it SF or fantasy? Why wouldn't the BMW 3 previously mentioned do all those things - except that it wouldn't have to? It could take itself to the petrol/gas station every other week or so when it needs more fuel, and spend a fraction of the time there that any EV spends in recharging . No need to mess around with charging stations, assuming they are ever built in sufficient quantity to handle the immense additional numbers. The fueling infrastructure already exists and works quite well. Anyway, thanks for that - most amusing - but it is time to move on..   

Simple. For an automated ICE to do that it would require either a very expensive robotic delivery pump system to be built out or the hiring of attendants to pump gas when the auto ICE showed up which is also a big cost. More than adding 8 or so wireless mats around the gas station to service auto EV.

[Ward Smith + 6,615]

5 hours ago, footeab@yahoo.com said:

1st link: Yea, but the efficiency.  Of course the difference here is ability to make something work at all.  When I was working wind, we never even considered it as we were looking primarily at tower and blade cost.  Personally I think they are still making their blades wrong for low $$$.  True, my design would not look as good, but man would they have been much cheaper.  Slight icing problem though.  Here their auto transmission .... it all comes down to cost.  Frankly how they are erecting wind turbines is stupid IMO.  All we have to do is look how a crane is erected and why the Hell are we not doing so on wind turbines???  Would make transport of blades vastly cheaper as well.  I understood when the wind turbines were small, but they are literally 10X larger now, yet their building practices have NOT CHANGED.  It is beyond stupid.  Good find on that article by the way.  Thought they were going to be talking about hydraulic swash plates and bearings for converting thrust into power.  😀  It is not as if the tower is not already subject to cyclic fatigue loads.  Heck if done right, could probably cancel out the cyclic load while generating power as well through the main bearing.  All comes down to $$$. 

2nd link shows 90% efficient Brushless DC.  Ok.  We know.  Maybe you read the inverter eff at 95%?

3rd link shows: ???  A vacuum cleaner for BLDC.... Yes, everyone wants small BLDC in Everything as they are vastly superior to induction or shunt.  Random thought yesterday when mixing cookie dough and the mixer literally almost died because I was mixing a triple batch of gingerbread cookies: I would love a Brushless AC powered kitchen aid mixer.  😀

I thought you'd like the wind power article. I agree they're not doing them right. But they don't need to if they're being subsidized to do things wrong. 

2) the link talked about brushed motors. So did the quote I inserted from the link. [edit I couldn't believe you'd make that mistake so went back and realized you must have meant the IEEE link. I'll find some more recent numbers tomorrow if I can find time].

The third link was an example app for the TI controller chips. I'd rather see BLDC across the board for current AC motor applications. Dyson has a BLDC vacuum cleaner and it's pretty excellent. 

 

Edited June 1, 2020 by Ward Smith
Trying to figure out which links are referenced

[ronwagn + 6,290]

On 5/29/2020 at 11:30 PM, Douglas Buckland said:

Exactly!

Where do you buy a new car for those prices? China, India, Malaysia? I thought cheap little cars weren't selling.

[Ward Smith + 6,615]

@footeab@yahoo.com found This inverter design over 98% remembered I'd looked at it a few years ago and even tried to order the board. 

Given an almost 99% efficient inverter and knowing how BLDC motors work, you can create a "window of operation" where the motor runs almost equal to the inverter because of the permanent magnets. Watts in, watts out, work done. 

Maybe I'll Buy some of these slotless BLDC motors to play with. See how efficient I can make them run. 

Edited June 1, 2020 by Ward Smith
Added link

[footeab@yahoo.com + 2,129]

5 hours ago, Ward Smith said:

@footeab@yahoo.com found This inverter design over 98% remembered I'd looked at it a few years ago and even tried to order the board. 

Given an almost 99% efficient inverter and knowing how BLDC motors work, you can create a "window of operation" where the motor runs almost equal to the inverter because of the permanent magnets. Watts in, watts out, work done. 

Maybe I'll Buy some of these slotless BLDC motors to play with. See how efficient I can make them run. 

This is ONLY the motor drive controller which is 98% efficient, not the motor itself.  If it is the other way around, then I need to order several billion of these controllers and make a whole pile of 400MW generator to change out all the high pressure 92% efficient synchronous generators.  Then I need to order many billion more and electrify all the gas/oil pumps and wind turbines would DROOL over this as it should be near infinitely variable RPM if you make trees of these with different numbers of poles on each "branch" and therefore voltage will not brown out due to wind gust, or some other station goes down creating a giant current draw. 

Edited June 1, 2020 by footeab@yahoo.com

[Jan van Eck + 7,558]

16 hours ago, Ward Smith said:

Interested in what @Jan van Eck knows about this, since he builds electric bikes with I assume BLDC motors. 

Electeric bicycles are built with brushless motors specifically to remove the maintenance aspect of cleaning commutators (and replacing brushes) that you have with brush-type motors.  The "efficiency" part is not interesting.

Remember that "efficiency" means how much or how little of the current draw is converted to heat.  If the motor is not getting hot then you have a decently-efficient motor.  I have seen electric bicycle brushless motors re-worked by amateurs to include air-cooling holes drilled into the casing, to remove some heat, when they jack up a smallish motor to 10 KW draw, by building their own controller.  The idea behind putting more current through a brushless motor is to get the bike to go faster, and indeed using that technique a bicycle can be boosted to up to and even over 55 mph on the flat.  There is a guy up in Canada, in B.C., that will sell you his set of plans to go build your own 55 mph commuter bike, but it is living on the edge of burn-out.  Plus, you have to be a certified madman to actually ride the thing  (he commutes to his job as an emergency medical technician).   Just because it can be done, does not imply that it should be done. 

A brushless motor will stall under certain conditions,  when attempting to start  under load on an up-grade.  Then you have to "pedal" about 1/4 revolution to get the motor engaged.    A minor annoyance. But if you use a brush motor then it is best to have it mounted outside the hub, and that means engaging the drive chain continuously.  That implies the chain needs to be enclosed, to keep your clothing from being ensnared.  And the owner will have to be mechanically adept, to remove, disassemble, and clean those commutator slots.  So the industry has pretty much gone over to brushless hub-motors to avoid the owner problems.  

The Mainland Chinese seem to have a lock on the manufacture of those hub-motors (!).   Oh, well. 

Edited June 1, 2020 by Jan van Eck
typing error

[SERWIN + 749]

I have been wondering about the whole "promise" to make them cheaper, but my logic would tell me that if I bought a Tesla two years ago for about 60k, and now he's selling it for 40k? That would make me feel like I was suckered, I wouldn't be able to go back and get another one. It also devalues the models that are already sold, so a double screwing is going on with this one..... I do believe we have a long way to go before they become primary vehicles on the raod. Coupled with the fact that the engineers obviously missed the whole thing about the car having enough brains to just STOP when the driver isn't responding and driving into things? No friggin' way I would EVER buy a Tesla, piss poor logic was used when making the software for the auto drive system on this one. 

[Jan van Eck + 7,558]

12 hours ago, Ward Smith said:

I thought you'd like the wind power article. I agree they're not doing them right. But they don't need to if they're being subsidized to do things wrong. 

And that is exactly the problem.  The wind projects (at least in the USA and Canada) are not being built to actually produce power.  They are built so that the "general partners" can go collect the cash subsidies, structured as "Invest tax credits," which historically have amounted to 30% of the project CAPEX.   If your project is $100 million then you as the general partner pick up a cheque from the Feds for $30 milllion just to put the deal together.  That allows you to buy a mansion on Martha's Vineyard  ($11 million), a really nice yacht  (figure on $6 million), and a lot left over for hookers and blow. 

[Jan van Eck + 7,558]

4 minutes ago, SERWIN said:

piss poor logic was used when making the software

Tesla is not marketed to clear-thinking scientists or hard-headed logicians.  They are sold to the "True Believers," just as the financing for the England-France Channel Tunnel was subscribed to by the True Believers.  That it made no financial sense and was doomed to bankruptcy to blow off the debts was not an issue; the Believers put their money into it nonetheless. As one Frenchman indignantly responed when quizzed on his purchase of Chunnel debt instruments:  "It is an honor to buy these bonds for the Tunnel."    And you get the same phenomenon with Tesla, both as investors and as product buyers.  

[Ward Smith + 6,615]

5 hours ago, footeab@yahoo.com said:

This is ONLY the motor drive controller which is 98% efficient, not the motor itself.  If it is the other way around, then I need to order several billion of these controllers and make a whole pile of 400MW generator to change out all the high pressure 92% efficient synchronous generators.  Then I need to order many billion more and electrify all the gas/oil pumps and wind turbines would DROOL over this as it should be near infinitely variable RPM if you make trees of these with different numbers of poles on each "branch" and therefore voltage will not brown out due to wind gust, or some other station goes down creating a giant current draw. 

Ah the problem of scaling. I already mentioned limiting current and here you are running motors backwards to try and create power. Let's remember the premise here, EV's that get decent mileage on a charge. There's a good reason owners have to put fences around engineers, otherwise they get into analysis paralysis while making perfect the enemy of good. 

[Ward Smith + 6,615]

3 hours ago, Jan van Eck said:

Electeric bicycles are built with brushless motors specifically to remove the maintenance aspect of cleaning commutators (and replacing brushes) that you have with brush-type motors.  The "efficiency" part is not interesting.

Efficiency is interesting to me on battery operated devices especially. 

Unfortunately giving a number for "efficiency" for a motor is like giving an internal combustion engine a number for "mileage". We need to know the conditions said efficiency or mileage is achieved under. The Texas Instruments link above goes into some detail on it but of course they're focused on their efficiency and don't care about the motor.  

3 hours ago, Jan van Eck said:

The Mainland Chinese seem to have a lock on the manufacture of those hub-motors (!).   Oh, well. 

 This is a shame, they do control the REE supply and neodymium magnets for now. 

[Jay McKinsey + 1,489]

4 hours ago, Jan van Eck said:

 That it made no financial sense and was doomed to bankruptcy to blow off the debts was not an issue; the Believers put their money into it nonetheless. As one Frenchman indignantly responed when quizzed on his purchase of Chunnel debt instruments:  "It is an honor to buy these bonds for the Tunnel."    And you get the same phenomenon with Tesla, both as investors and as product buyers.  

Sounds more like a description of the debt fueled shale oil industry of the past few years.

[footeab@yahoo.com + 2,129]

4 hours ago, Ward Smith said:

Ah the problem of scaling. I already mentioned limiting current and here you are running motors backwards to try and create power. Let's remember the premise here, EV's that get decent mileage on a charge. There's a good reason owners have to put fences around engineers, otherwise they get into analysis paralysis while making perfect the enemy of good. 

10% cheaper power is paralysis analysis?  10% cheaper drilling costs?  10% cheaper lifting costs?  Wind turbines which can operate at low wind speeds? 

Superior regenerative braking efficiency?  For city driving this DC drive controller is FAR more relevant, than its overall efficiency.  So, UPS, FEDEX, mail and delivery services around the world... Oh yea. 

EDIT: PS: And only reason TI published this is because they could not sell it.  That is how the engineering world works.  You sit on a design etc and NEVER publish till it is 100% guaranteed your product is useless and then you publish.  TI obviously could not sell it as the brusheless drive controller used in every compact BLDC device are all the same and designed quite a while ago even if it is slightly inferior. Second of all it is made in China even though it will say Milwaukee on the side or Dewalt or Ryobi or .... the controller is the same and incentive to change is near zero to justify the cost.  After all, we barely got Brushless motors in hand tools even though they have been around for DECADES. 

Edited June 1, 2020 by footeab@yahoo.com

[Ward Smith + 6,615]

11 minutes ago, footeab@yahoo.com said:

10% cheaper power is paralysis analysis?  10% cheaper drilling costs?  10% cheaper lifting costs?  Wind turbines which can operate at low wind speeds? 

Superior regenerative braking efficiency?  For city driving this DC drive controller is FAR more relevant, than its overall efficiency.  So, UPS, FEDEX, mail and delivery services around the world... Oh yea. 

EDIT: PS: And only reason TI published this is because they could not sell it.  That is how the engineering world works.  You sit on a design etc and NEVER publish till it is 100% guaranteed your product is useless and then you publish.  TI obviously could not sell it as the brusheless drive controller used in every compact BLDC device are all the same and designed quite a while ago even if it is slightly inferior. Second of all it is made in China even though it will say Milwaukee on the side or Dewalt or Ryobi or .... the controller is the same and incentive to change is near zero to justify the cost.  After all, we barely got Brushless motors in hand tools even though they have been around for DECADES. 

You lost me on the bolded sections. Was that in reply to something else? Are you saying I'm against improvements when my every post has been about incremental improvement? 

I was talking about efficiency, which really matters with battery operated devices and you switched to power generating?

TI was selling enough of these kits that they were completely sold out by the time I contacted them, and that was right after seeing a tiny ad in Electronic Design. I thought you were an electrical engineer? The electronics for the BLDC motors were prohibitively expensive until the past few years. It is only because of TI and others that they've come so far down in cost. That is why you can have BLDC in a Dewalt drill and not break the bank. The motor prices haven't moved much, the controllers have come down by an order of magnitude. 

Not sure why you're arguing about this. 

[footeab@yahoo.com + 2,129]

@Ward SmithWhy the Hell are you posting controller efficiencies and pretending they are motor efficiencies?  Controller efficiencies only matter when you have WIDE RPM/Power ranges and then you do not care about efficiency in those cases.  Why I typed what I did.  Because if what you typed was true, then the stuff you bolded in my post would be true and it is not as those controllers have been around for a very long time.  True, they were larger... SO what? 

[Ward Smith + 6,615]

29 minutes ago, footeab@yahoo.com said:

@Ward SmithWhy the Hell are you posting controller efficiencies and pretending they are motor efficiencies?  Controller efficiencies only matter when you have WIDE RPM/Power ranges and then you do not care about efficiency in those cases.  Why I typed what I did.  Because if what you typed was true, then the stuff you bolded in my post would be true and it is not as those controllers have been around for a very long time.  True, they were larger... SO what? 

I think you don't know how a BLDC works, period.  If you did, you'd understand the controllers relationship to BLDC efficiency. Within one or two percent, within the optimum operating region they are at unity. Since you've obviously been on shut down too long you're getting far too temperamental about this. If brushed DC motors can achieve 90% efficiency with a damn brush scraping on the rotor, you can bet your ass BLDC can do Much better. Not sure why you're arguing, not sure why you're being obstinate. I'm sorry for that, maybe you're uncomfortable out of your element. 

[footeab@yahoo.com + 2,129]

1 hour ago, Ward Smith said:

I think you don't know how a BLDC works, period.  If you did, you'd understand the controllers relationship to BLDC efficiency. Within one or two percent, within the optimum operating region they are at unity. Since you've obviously been on shut down too long you're getting far too temperamental about this. If brushed DC motors can achieve 90% efficiency with a damn brush scraping on the rotor, you can bet your ass BLDC can do Much better. Not sure why you're arguing, not sure why you're being obstinate. I'm sorry for that, maybe you're uncomfortable out of your element. 

Because brushes are only at best 2% of losses is why. 

Lets just say that if you are right and 98% is the new normal, then you and I will shortly have ~10% lower electricity bills.  Also means turbines can be run at non optimum RPM and achieve higher efficiency. 

[footeab@yahoo.com + 2,129]

9 hours ago, Ward Smith said:

I think you don't know how a BLDC works, period.  If you did, you'd understand the controllers relationship to BLDC efficiency. Within one or two percent, within the optimum operating region they are at unity. Since you've obviously been on shut down too long you're getting far too temperamental about this. If brushed DC motors can achieve 90% efficiency with a damn brush scraping on the rotor, you can bet your ass BLDC can do Much better. Not sure why you're arguing, not sure why you're being obstinate. I'm sorry for that, maybe you're uncomfortable out of your element. 

You certainly do not: HERE: https://www.masinaelectrica.com/motor-performance-evaluation-test-bench-setup/

Is how you actually calculate it.  Big Hint: his drive efficiency is 96.731% efficient.  Yours claims 98%.  I'll let you figure out what the actual overall efficiency is.  HInt: It is NOT 96.731%, nor is it 98% if he switched his drive for the TI 98% drive.  

Neodynium iron cobalt magnets die at temperature so how you plan on keeping these generators etc below 100C, good luck.  Old Memory: GM tried this on new starters.  Worked great until placed in the desert and they could not start a car anymore...  True that was 40 years ago, but... these properties have not changed any nor are we using new types of magnets in these permanent magnet brushless motors.  Why they all have overtemp sensors and they turn off.