Відео

It depends on the machine type, the dual rotor single stator or yokeless style machines usually use oil cooling, the single rotor dual stator machines are easier to cool the stators as they can be mounted to the cooling jacket like the Turntide/Avid EVO axial flux

On a like for like basis in terms of diameter and volume either of the axial flux topologies, and optimising for that speed I would think the dual stator single rotor would come out best. Think of the active material surface area

In air flow you get contamination including moisture, dirt and dust which must be dealt with for a reliable long life application. For more power dense motors air cooling is not enough. You must have liquid cooling to the stator at least which is more difficult when it is mounted inside the rotor to get a good effective pathway and surface area.

I think Mercedes are starting to talk openly now about their model plan for axial flux machines, so within their next development cycle (3-4 years) I suspect. The other cars using axial flux are really "popular" but more as a pinup poster ;-)

Я у себя в мастерской делаю такие двигатели!! У меня на канале крайнее видео , и мне не надо быть компанией мерседес , чтоб их производить💪

Not likely. However, see Raxial motors.

great - we also have an axial flux motor explainer video coming watch this space!

Hopefully you have seen it already but in case not please find that animation explaining the axial flux motors here ua-cam.com/video/B0CNZPenCb8/v-deo.html

Sure will do@@etech49

Hello to you to, we hope you have enjoyed our content about electric motors, EV’s and more!!!

This all comes down to the application and thermal management. The limiting features of any motor are the ability to generate magnetic repulsion force in the air gap and the heating effect that accompanies this in both the rotor magnetic circuit and the stator. With the thermal limit of the materials being the key. For a high peak power you need the ability to create a big magnetic force for a short time. This needs a large electrical current and to limit the rate at which it heats the other parts of the motor, as well as a strong rotor magnetic field. There isn't a simple answer and you could make a design of either radial flux or axial flux, for very short peaks the thermal mass of the motor components is more important than overall ability to cool. But this tends to not be desirable in most applications, unless its for a stationary machine!

@@etech49 it is for a racing motorcycle

@@etech49 thanks a lot for you reply I appreciate very your fast response.

A drone typically uses an external rotor motor, where the stator is inside and the rotor is outside, like this ua-cam.com/video/HSd8Xp7OIh0/v-deo.html This has the advantage of more mechanical advantage, so more torque for lower speed motors. But inner rotor allows you to spin faster and get more power density, which is good if you can use a reduction gearbox.

That’s impressive and you will do very well with that technology if your claims can be proved. The purpose of this video was to help people understand more about different types of existing motor though, not show an innovation or new idea this is meant to be an overview of existing established tech 👍

We would happily take a look at this, please send over some more info

Hi, as this is a podcast episode it is audio only. You can hear the full interview. But we don't record video for the podcast episodes. We tried this in the past but it just did not work for us. So we chose to go audio - you can also find the podcast episodes in all major podcast apps apple, amazon, spotify etc We do have other video content on the channel and more coming so subscribe to make sure you don't miss anything!

It would be longer than the axial flux, and it was also held constant through the comparison. The reason the relationships vary as they do is because of the active surface area. If you think the surface area of a cylinder 2πrl excluding the end faces for radial and surface area of the end faces for axial 2πr^2 its really a geometry play of how much active surface you can get in.

Thank you

Thanks for the comment!

@@etech49 Thanks a ton for reply dear friend please change UA-cam settings su that we can subscribe to your channel dear, great work

Glad you enjoyed it!

Hi sorry for the slow reply, this one slipped under the radar. You can connect with Ryan here: www.linkedin.com/in/ryan-maughan-a2893610/

Hi Eyenor, we know you connected and got an answer already from @Ryan but we are putting his reply here to hopefully help others as well: DC motors have several issues for use in a variable speed application like an EV traction system they did used to be common if you look back at old trains and teams. But ultimates eliminated because of the issues. Brushed machines suffer from wear and have loses associated with the excitation and very poor speed/torque control. BLDC is common in applications like ancillary drives, it is too coarse for traction and is effectively 3 phase anyway! For ERPM radial look at Protean motor drive, or the model drone market advantage is simply greater relative active surface area in air gap and mechanical advantage placing the air gap further away from the rotating axis. But these machines are very hard to make reliably! For dual rotor single stator axial Yasa, Magnax, and Emrax For single rotor my old business Avid, now Turntide or Heinzmann

Great comment thank you, yes that’s true Sofc fuel cells like those produced by Ceres power do have some advantages over PEM and also some disadvantages. In addition to your points I also think the higher temperatures can cause issues. But a really interesting tech, check out episode 53 with Mark Selby from Ceres power etech49.com/ep53-mark-selby-sofc-fuel-cells/

Yes they typically have an onboard converter to boost the voltage to the required level. New high power charging infrastructure e.g. Ionity will typically work at 800V and can output lower voltages too.

Awesome, thank you!

I imagine this would be quite complex as there are a lot of interactions in the emissions control system. EGR usually results in leaner combustion and lower peak cylinder temperature. The new program is likely actuating the egr system more regularly. They may also have adjusted the injection system operating points and being doing something with aftertreatment like trying to run at a higher exhaust temperature or back pressure. But I am not aware of the specifics of the changes made, sorry. The emissions of the system are dependant on whats going in boost pressure, charge temperature, fuelling strategy and EGR, what is happening during combustion so peak cylinder pressures and temperatures and then what is being done to it when it comes out DPF, SCR etc The conditions for most efficient combustion also are typically where the most NOx and pm are created i.e. highest cylinder pressure and temperature.

Your car was designed to run optimally and to "fudge" the test figures. You have now updated your car so it actually RUNS on the "be good and don't make nasty emissions", instead of "run properly for economy and power" - and just fudge the emission test when it happens. Your engine WAS set up close to optimally, you have now downgraded it to "run like a pig, but don't give off nasty emissions". This really should not be a surprise. The whole POINT of the "naughtyness", was to give you maximum performance and reasonable economy while ALSO being able to detect when it was being tested - and then (just for that test), run for minimum emissions, rather than maximum oomph. Now it JUST runs in "low emission mode". If you can find someone that can "downgrade" you back to where you were, you can have all your performance back.

Generally in an axial flux motor there is unused end winding area in the radial direction, they seem to be utilising what was the end winding to form an additional active magnetic area.

@@etech49 does Tesla use radial motor ? If they do, why don't they use axial flux motor to increase acceleration for higher performance ? Since Mercedes bought yasa, they must be using axial flux design for their future cars...

@@ps3301 All Tesla models, and all EVs of any brand with significant production volume, use internal rotor radial-flux motors. The motor is a small part of the EV, in terms of volume, mass, and cost, so there is not much to be gained by a motor design change.

Hi Alex, it certainly is please connect with Ryan here and send him a message: www.linkedin.com/in/ryan-maughan-a2893610/

Brilliant, really pleased that it was helpful! There is lots of potential for Axial flux motors in new applications

Thanks for watching, we would recommend using a pair of AC motors with a speed controller that converts the battery DC into controllable 3phase AC

Glad it helped, we don't have that on a video sorry. These are relatively complicated machines to design due to the 3D magnetic flux. Most design packages can only design in 2D so you need to convert the geometry into a 2D radial approximation to do simple calcs (basically a pair of larger diameter radial motors with an equivalent active surface area.

Wow, thank you! Great to get this feedback :-)

Hi thanks for the question and sorry for the slow reply. Please find a link to an old paper where this relationship was first described. pdfs.semanticscholar.org/71ed/336bb0a934ac3ccf92397deb6a3497e6e84f.pdf It is a simple geometry feature of the active magnetic area being on the faces of the machine rather than the internal diameter so the active area increased d^3 rather than d^2

Hi and thanks for the question and sorry for the slow reply! The answer to this is not straight forwards. Fundamentally the 800V is being used to drive lower system currents to reduce ohmic loses which are proportional to I^2, but it is also an enabler to higher motor speeds it is basically easier to increase motor rpm with a higher voltage, higher speed motors usually make less torque and we use a mechanical gearbox to restore this. You may ask why bother making a high speed motor then? Because you can get the same power (and ultimately torque after its been through the gearbox) with less active material so a lighter/cheaper motor

Thanks for the comment!

Thanks for the comment and sorry for taking such a long time to reply! 800V systems bring many benefits for a given power it halves the current and system loses are proportional to the square of the current, so throughout the system there are benefits with a higher voltage leading to smaller power cables, because the cross sectional area is a function of current carrying capability lighter motors and power electronics and less cooling required because of lower ohmic heating. It also enables faster charging speeds again because of the reduced current. For a given charge speed I would say that an 800V system would suffer lower levels of degradation than a lower voltage system because of the lower current flow and reduced ohmic heating, but if we are using 350kW charging all the time it could lead to a reduction in cell lifetime - however the reality is I do not believe anyone would have the need to do that.

Flywheel systems were developed several years ago at the time battery tech was no where near as good as it is now. So those companies had issues achieving commercialisation. Flywheel is still around but has a niche of applications where it is useful vs what can now be done with a battery system.

@@etech49 thankyou for taking the time to reply.

Hi and thanks for the question, actually 800V would lead to less battery degradation under like for like conditions. This is because the current flow would be halved in the system, leading to a substantial reduction in ohmic heating and other degradation mechanisms. But as 800V is typically also used to unlock additional vehicle performance and ultra fast charge speed if this performance and ultra fast charging is continuously used then you there could be higher degradation. But this is the same with any system voltage.

Hi and thanks for the comment, diesel calibration will continue to be required for several more years but as many OEM's have already stopped or significantly reduced their engine development and the emissions reduction steps are largely all now complete I believe there is a reduction in demand now for diesel calibration