Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

New Electric Motor Could Boost Efficiency of EVs, Scooters, and Wind Turbines

spectrum.ieee.org

Post reply on HN
Print view View original

21–30 of 52 posts

Re: New Electric Motor Could Boost Efficiency of EVs, Scooters, and Wind Turbines

#21

Post by balfirevic »

cagenut wrote: post #10

For those wondering what a seemingly marginal difference would mean in real world examples, take a look at this video from a conference on electric aircraft design a year ago: High Torque, Low RPM Motors – Key Enablers of Quiet Flight https://www.youtube.com/watch?v=jXd4M_pZl78

Transferse flux motors (from the talk) have a "too good to be true" ring to them. I wonder what will be of them in 5-10 years.

Increasing the torque density compared to the current state-of-the-art would be a big deal for robotics applications.

Re: New Electric Motor Could Boost Efficiency of EVs, Scooters, and Wind Turbines

#22

Post by frankus »

magduf wrote: post #18

This whole thing sounds like a scam. Even worse, it's in an IEEE article. I'm really glad I ended my subscription to them so many years ago if they've fallen to these depths. Just look at this one line from their article: >Torque is the amount of work that a motor or engine produces, typically measured on a per-revolution basis. No, that's energy, not torque. Torque is rotational force. Torque times rotation is power…

It's not unheard of for EVs to boost the battery voltage to a higher level before feeding into the inverter that powers the motor (e.g. https://www.eetimes.com/document.asp?doc_id=1281167). There are some advantages to running the inverter at higher voltage (cheaper switching devices and smaller wires), although I do find it surprising that this apparently sometimes offsets the cost of the boost converter.

But I believe this is much less common with lithium ion batteries (~3.6 V/cell) than it was with NiMH (~1.2 V/cell).

Re: New Electric Motor Could Boost Efficiency of EVs, Scooters, and Wind Turbines

#23

Post by tln »

magduf wrote: post #18

This whole thing sounds like a scam. Even worse, it's in an IEEE article. I'm really glad I ended my subscription to them so many years ago if they've fallen to these depths. Just look at this one line from their article: >Torque is the amount of work that a motor or engine produces, typically measured on a per-revolution basis. No, that's energy, not torque. Torque is rotational force. Torque times rotation is power…

> >The system incorporates a purely electronic transmission

> A what? Not possible: a transmission is a mechanical item that converts rotary motion into rotary motion at a different speed and torque level

Other articles about this company explain what this electronic "transmission" is: variable windings. So they can switch from 6 phase to 4 to 3, which will change the RPM per volt. I think.

https://insideevs.com/news/364852/linear-labs-hunstable-elec...

Re: New Electric Motor Could Boost Efficiency of EVs, Scooters, and Wind Turbines

#24

Post by JumpCrisscross »

MobileVet wrote: post #16

These guys have definitely spent some money on PR since closing their investment round in April. They have placed 4+ articles with many of the same talking points, pictures and video over the last 2 weeks: https://www.cnet.com/roadshow/news/linear-labs-electric-turb... https://jalopnik.com/a-texas-startup-claims-to-have-made-the... https://newatlas.com/linear-labs-hunstable-electric-motor/60... https://insideevs.com/…

> These guys have definitely spent some money on PR

And wasted it. Jalopnik? InsideDevs.com? CNET? Seriously?

Re: New Electric Motor Could Boost Efficiency of EVs, Scooters, and Wind Turbines

#25

Post by MobileVet »

JumpCrisscross wrote: post #24
MobileVet wrote: post #16

These guys have definitely spent some money on PR since closing their investment round in April. They have placed 4+ articles with many of the same talking points, pictures and video over the last 2 weeks: https://www.cnet.com/roadshow/news/linear-labs-electric-turb... https://jalopnik.com/a-texas-startup-claims-to-have-made-the... https://newatlas.com/linear-labs-hunstable-electric-motor/60... https://insideevs.com/…

> These guys have definitely spent some money on PR And wasted it. Jalopnik? InsideDevs.com? CNET? Seriously?

I would have agreed... but if that all helped them book IEEE, then it was worth it. From a reputation standpoint, IEEE could give them quite a bit of cache.

Re: New Electric Motor Could Boost Efficiency of EVs, Scooters, and Wind Turbines

#27

Post by blacksmith_tb »

MobileVet wrote: post #25
JumpCrisscross wrote: post #24

Earlier quoted context omitted.

> These guys have definitely spent some money on PR And wasted it. Jalopnik? InsideDevs.com? CNET? Seriously?

I would have agreed... but if that all helped them book IEEE, then it was worth it. From a reputation standpoint, IEEE could give them quite a bit of cache.

I'm all in favor of more cache, but I think that was supposed to read 'cachet'...

Re: New Electric Motor Could Boost Efficiency of EVs, Scooters, and Wind Turbines

#28

Post by hinkley »

jacquesm wrote: post #4

10% is nothing to sneeze at but it also does not mean it is a game changer. I like the way the coil ends are described, they are 'dead' weight in a normal motor because they don't contribute to the flux but they do contribute to the resistive losses in the motor. But that 10% of the length of the winding that sits outside of the coil chambers is not responsible for 10% of the electric consumption of the motor, which…

My take was the transmission, DC-DC converter, and 10% efficiency gain were essentially the same conversation.

Transmissions and converters all result in transmission losses. They're also more components to purchase, install, and maintain. So if they can build a motor that embodies some of those qualities, that's an improvement, even if the resulting motor were slightly less efficient (which they say is not the case).

If an electric car is using three-phase AC, then there's an inverter in there (because batteries do not come with three-phase AC). I don't believe that's as much loss as DC-DC but it's not nothing.

Re: New Electric Motor Could Boost Efficiency of EVs, Scooters, and Wind Turbines

#29

Post by aidenn0 »

Gibbon1 wrote: post #19
cagenut wrote: post #10

For those wondering what a seemingly marginal difference would mean in real world examples, take a look at this video from a conference on electric aircraft design a year ago: High Torque, Low RPM Motors – Key Enablers of Quiet Flight https://www.youtube.com/watch?v=jXd4M_pZl78

I watched about half that. Interesting bit that newer high bypass turbofans need gearing to match the turbine optimal shaft rpm to the fan's lower rpm and higher torque. Brings up High torque gears -> weight High speed gears -> maintence hassle If I get this talk right the hope is the difference in weight penalty for an advanced direct drive electric motor vs a gear train is nil. This guy is pushing a very high effic…

Random OT trivia, but the first turbofan to fly was geared, and there have been commercial geared turbofans in use at least since the early 70s.

It's always been a trade off of fewer compressor stages vs. not having gears. Either of extra compression stages and gears add weight and reduce efficiency, so it's always a tradeoff.

Post reply on HN