Honda Power Unit Hardware & Software

[J.A.W.]

Unless Honda is being 'too clever by 1/2' - by using electromagnetic bearings..
..& suffering unforeseen NVH/EM 'fluctuations' that play havoc with them too..

[PhillipM]

I see no advantages to any of those over an oil fed journal, apart from maybe a stiffness benefit, but you can do that with oil fed too if you really want to.

[GhostF1]

I see no advantages to any of those over an oil fed journal, apart from maybe a stiffness benefit, but you can do that with oil fed too if you really want to.

Apart from magnetic bearings being completely absent of any mechanical degradation and are utilised for their advantage over other bearing types in high speed applications, which ironically is this exact situation. Their disadvantage, as J.A.W said, would be field disruptions that cause the field suspension to cut out and basically drop the shaft, which spinning at over 120,000rpm, could cause some pretty dramatic failures, damaging surrounding parts also.. actually it's an interesting point, these vibrations, engine/gearbox resonance at certain rpm, drivetrain noise, external stress.. is this possibly moving the MGU-H shaft out of the levitation field and causing issues/failures? I'm probably completely wrong, but the idea is certainly interesting.
I'm also not sure how confident I am in saying they'd definitely be using them, but with these Power Units and the lengths manufacturers have gone to for minute gains here and there and with Honda attempting extremes to leapfrog, I've learnt not to discount anything.

[gruntguru]

High-speed, lightly-loaded shafts present some unique vibration problems. For example plain journal bearings are susceptible to "oil whirl" where a wedge of oil rotates with the shaft at 1/2 shaft speed. This presented a serious problem in the early development of turbochargers and was cured using the familiar "fully floating" bearings which damp the oil whirl problem with a second oil-filled clearance area surrounding the bearing shell.

[AJI]

Unless Honda is being 'too clever by 1/2' - by using electromagnetic bearings..
..& suffering unforeseen NVH/EM 'fluctuations' that play havoc with them too..

Interesting... Would they be using ball bearing for basic placement and then EM for a potentially frictionless bearing?

[J.A.W.]

Unless Honda is being 'too clever by 1/2' - by using electromagnetic bearings..
..& suffering unforeseen NVH/EM 'fluctuations' that play havoc with them too..

Interesting... Would they be using ball bearing for basic placement and then EM for a potentially frictionless bearing?

Or even perhaps, 'barrel roller' bearings..

[AJI]

The more I think about this the more I think J.A.W. may have hit the nail on the head!
An EM bearing would explain why Honda was so confident of a significant step change in performance for the new PU, and it would also explain why (while the technology is in its infancy) they are having terrible trouble on the track that was hard to detect on the test-bed.

[nzjrs]

The more I think about this the more I think J.A.W. may have hit the nail on the head!
An EM bearing would explain why Honda was so confident of a significant step change in performance for the new PU, and it would also explain why (while the technology is in its infancy) they are having terrible trouble on the track that was hard to detect on the test-bed.

Is it really feasible that a marginal decrease in friction of the MGUH shaft due to the type of bearing causes a step change in whole PU performance. It doesn't seem realistic to me.

[toraabe]

The more I think about this the more I think J.A.W. may have hit the nail on the head!
An EM bearing would explain why Honda was so confident of a significant step change in performance for the new PU, and it would also explain why (while the technology is in its infancy) they are having terrible trouble on the track that was hard to detect on the test-bed.

Is it really feasible that a marginal decrease in friction of the MGUH shaft due to the type of bearing causes a step change in whole PU performance. It doesn't seem realistic to me.

It took Mercedes one year just to get their TURBO / MGU-H reliable...

[nzjrs]

The more I think about this the more I think J.A.W. may have hit the nail on the head!
An EM bearing would explain why Honda was so confident of a significant step change in performance for the new PU, and it would also explain why (while the technology is in its infancy) they are having terrible trouble on the track that was hard to detect on the test-bed.

Is it really feasible that a marginal decrease in friction of the MGUH shaft due to the type of bearing causes a step change in whole PU performance. It doesn't seem realistic to me.

It took Mercedes one year just to get their TURBO / MGU-H reliable...

I agree it is unquestionably and absolutely critical for reliability. But a step-change in performance (as the poster I was replying to suggested)? I'm not so sure.

[AJI]

The more I think about this the more I think J.A.W. may have hit the nail on the head!
An EM bearing would explain why Honda was so confident of a significant step change in performance for the new PU, and it would also explain why (while the technology is in its infancy) they are having terrible trouble on the track that was hard to detect on the test-bed.

Is it really feasible that a marginal decrease in friction of the MGUH shaft due to the type of bearing causes a step change in whole PU performance. It doesn't seem realistic to me.

I give you that a marginal decrease in friction in the MGU-H seems almost inconsequential, however, 4 years into the PU era everone is chasing numbers, no matter how small those numbers are.

What I was really referring to was that Honda have implied that they are now on-par with ICE efficiency, and as the specifications are relatively fixed for the ICE that only leaves innovation in other areas for further gains. So the 'step' is really ICE efficiency coupled with some sort of silver bullet, and there can't be many silver bullets left..?

There have been a lot of odd comments about the new PU from Honda about a lack of correlation from test-bench to track and a huge amount of speculation on forums ranging from, 'Honda are incompetent', which I find hard to believe, to interesting speculation on innovation, which we have heard today. Sure, an EM bearing won't yeild huge gains, but when you're chasing numbers any improvement is good, so the concept is plausible. That, coupled with their public yet incomplete 'resonance' explanation, points to something that is a poorly realised innovation.

[Tommy Cookers]

an EM bearing suffering from radiated EM 'interference' from outside ?

the bearings are in the middle of a radiated EM factory that is officially called the MGU-H
the H and the K work by high voltages switched hundreds of times a second, these voltages are produced by switching thousands of times a second

ie any EM factor in this case is surely designed for and testable on day 1
(the 'beauty' of these modern devices is that they manufacture EM at particular frequencies so it's 'easy' to design out 'interference' problems)
http://www.celeroton.com/en/technology/ ... rings.html
maybe not so all possible mechanical ie vibratory disruptions to bearings etc
though you might think that all possible vibratory disruptions could affect the H itself (conductors/'windings' etc)

and bearing friction is surely minute compared to other losses in these electrical machines and in the electrics that make them work ?

[J.A.W.]

an EM bearing suffering from radiated EM 'interference' from outside ?
the bearings are in the middle of a radiated EM factory that is officially called the MGU-H
the H and the K work by high voltages switched hundreds of times a second, these voltages are produced by switching thousands of times a second

Perhaps that's what has the HRC engineers scratching their heads.. T-C?
If there is unexpected EM 'chatter', then how difficult is it - to determine/remedy - its source?

[AJI]

an EM bearing suffering from radiated EM 'interference' from outside ?
the bearings are in the middle of a radiated EM factory that is officially called the MGU-H
the H and the K work by high voltages switched hundreds of times a second, these voltages are produced by switching thousands of times a second

Perhaps that's what has the HRC engineers scratching their heads.. T-C?
If there is unexpected EM 'chatter', then how difficult is it - to determine/remedy - its source?

EM chatter plus mechanical vibration plus acoustic resonances plus, plus, plus... Sounds like the perfect storm and very hard to simulate on the test bench?

[stevesingo]

There is not only vibration to worry about, but gyroscopic loads through direction changes.