Electric motor design claims remarkable improvements
1–10 of 144 posts
Re: Electric motor design claims remarkable improvements
#2This article might not be well written.
What they describe I'm pretty sure I read about something very similar to this in the 90s, and as far as I can tell, never took off; either I am right, and I indeed read about this before, or the article is describing it badly.
PR statement via CNET as the source isn't helping, either.
Re: Electric motor design claims remarkable improvements
#3How cooling of rotor being achieved ? Energy, power and torque density of other motor designs are limited by their cooling capacity. Reluctance motor being externally cooled, has this as a prime selling point. I think for claimed improvement, it will need external cooling which is not mentioned in article.
Re: Electric motor design claims remarkable improvements
#4The video shows a picture of a motor about 99% similar to that of Cascadia Motion [1] based on the external appearance and cooling apparatus and not at all similar to the picture in the article.
1: https://www.cascadiamotion.com/uploads/5/1/3/0/51309945/ss_2...
Re: Electric motor design claims remarkable improvements
#5How cooling of rotor being achieved ? Energy, power and torque density of other motor designs are limited by their cooling capacity. Reluctance motor being externally cooled, has this as a prime selling point. I think for claimed improvement, it will need external cooling which is not mentioned in article.
There's a lot not mentioned. How do they move the rotor magnets in field weakening? How do they reconfigure the coils? How do they get 20 percent more efficiency when most are already over 90-95 percent?
Re: Electric motor design claims remarkable improvements
#6Feel free to educate me...
> The HET is a three-dimensional, circumferential flux, exterior
> permanent magnet electric motor with some interesting
> characteristics. For starters, it runs four rotors where other motors
> typically run one or two. The stator is fully encapsulated in a four
> sided "magnetic torque tunnel," each side having the same polarity,
> ensuring that all magnetic fields are in the direction of motion, and
> there are no unused ends on the copper coils wasting energy. All
> magnetism the system creates is thus used to create motion, and all
> four sides of the stator contribute torque to the output.
I'm not so sure about the idea that "unused ends" are "wasting energy". Simply put your finger on a small spinning motor and watch the current go up - increase the work done, increase the power usage. Typical losses in magnetic motors are:
1. Friction - Bearings, brushes, etc
2. Air - Typically cooling
3. Core - Hysteresis (changing polarity is not possible instantly) and eddy current losses (unwanted current flow)
4. Resistance - The coils themselves resist high current
Brushless motors are typically 85-90% efficient and brushed typically reach 75-80% efficiency [1]. Reducing the size a little, sure, but increasing the torque - I highly doubt for the same power input. I'm sure we will get to 95% efficiency within the next 10 years or so (with big money from the automotive industry pushing research), but it's highly unlikely we will get more than that outside of the a lab with super-cooled conductors.
Which is the other thing, increasing the amount of torque and reducing the size means greater heat generation. Any saving in size you're getting gets lost again just keeping the motor cool.
Anyway, the promises don't pass basic scrutiny, I would definitely need to see some numbers on this. It sounds like snake oil.
EDIT: Another thing - electric motors are already very efficient, you're getting more loss in other parts, such as voltage regulators, motor control circuitry, batteries (if you're using them), cooling, etc, etc. I just don't think this will translate to a massive improvement.
Re: Electric motor design claims remarkable improvements
#7This article might not be well written. What they describe I'm pretty sure I read about something very similar to this in the 90s, and as far as I can tell, never took off; either I am right, and I indeed read about this before, or the article is describing it badly. PR statement via CNET as the source isn't helping, either.
> I'm pretty sure I read about something very similar to this in the 90s,
Can you give more information please? I too highly doubt what they're selling here, would be interested to know what the previous efforts were.
Re: Electric motor design claims remarkable improvements
#8Electric cars don't usually have "gearboxes" proper. They use gears, fixed ratio reductors. This is not expensive nor is it fragile nor bulky nor inefficient.
The benefits that a very high torque motor could bring are real but marginal, a few percentage points improvements on the respective metrics. They could instantly be negated by, say, the lower initial reliability of a revolutionary design.
Re: Electric motor design claims remarkable improvements
#9Electric cars don't usually have "gearboxes" proper. They use gears, fixed ratio reductors. This is not expensive nor is it fragile nor bulky nor inefficient. The benefits that a very high torque motor could bring are real but marginal, a few percentage points improvements on the respective metrics. They could instantly be negated by, say, the lower initial reliability of a revolutionary design.
The article mentions that.
Re: Electric motor design claims remarkable improvements
#10How cooling of rotor being achieved ? Energy, power and torque density of other motor designs are limited by their cooling capacity. Reluctance motor being externally cooled, has this as a prime selling point. I think for claimed improvement, it will need external cooling which is not mentioned in article.
I think their power density claims must be comparing to the power density of a motor plus gearbox.