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

Post by magduf » Wed, Aug 21, 2019, 9:33 PM UTC

hinkley wrote: post #50

magduf wrote: post #49

Earlier quoted context omitted.

>This motor has 48 coils, and the ability to change what order and groupings they get powered. Ok, great, so now you have a bunch of discrete speeds you can run the motor at. How smooth a ride do you think that's going to provide? If you can't run a motor at any arbitrary speed within its range, it's useless for any kind of vehicle. >And what is 'battery voltage'? Battery voltage is something like 2.8 volts No, that'…

My point is it could be done, and these guys specifically claimed they don't need a DC-DC converter, so either they're lying, or there's something you and I don't understand. I'm just speculating on ways they could solve that problem. And you're giving so much salt back that I have to ask, do you believe they are lying? If so then don't beat around the bush. Just say it. You think they are frauds. > Yet somehow it wo…

They absolutely are frauds. Every time someone comes up with some new "breakthrough" like this, whether it's a new motor, or a new internal-combustion engine, it's a scam.

Also, I'm giving a lot of "salt back" because I'm an electrical engineer, so I can see how all this stuff is total garbage. You're obviously not. I've even worked on 3-phase "DC brushless" motors and their controllers, so I do know what I'm talking about. This stuff about not needing a DC-DC converter is BS. Of course you don't need a "DC-DC converter" if your motor is AC, which every motor without a mechanical commutator is. You still need some type of power control circuitry to drive the motor; you can't hook it up to a battery!

>Every time I've replaced my car battery, it's been because one cell failed after I let it deep discharge. Except once where 2 cells failed.

If you did a deep discharge, the other cells were degraded too, you just saw the cell that failed first.

>But you don't have to use that bus architecture. It's mechanically simpler and more robust.

Yes, actually you do, unless you want to have ridiculous currents at only 4.2V going to your inverter, which would be stupid because you'd need bus bars and would still have high resistive losses. This is the whole reason we have batteries with series-connected cells instead of parallel-connected cells.

Post by hinkley » Wed, Aug 21, 2019, 9:38 PM UTC

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…

Ten, maybe 15 years ago there was a spate of ACM topics about scheduling algorithms. I have some speculations that Apple incorporated similar logic into their laptops and phones, based on some brags they made about battery life improvements.

The observation is this: The faster you draw power from a battery, the less efficient the battery is. Therefore peak shaving goes a long way toward extending battery life. So a motor that is 10% more efficient may increase range by 12%. Or give you the same range with a battery 15% smaller (~100 lbs for some EVs).

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

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