Formula E

[radosav]

Little bit weird to see noise protection headphones used by teams. The commentator was annoying with last five minutes talking how one of those two guys will be the winner of first Formula E race, and than they crashed.

[Pierce89]

I enjoyed it, I took it for what it was, don't compare it to other racing categories unless you can point me in the direction of another fully electric series.

The US has the NEDRA. Its electric drag racing. Electric cars currently work better for races that are ~400m

[Andres125sx]

I enjoyed it, I took it for what it was, don't compare it to other racing categories unless you can point me in the direction of another fully electric series.

The US has the NEDRA. Its electric drag racing.

And you want to compare a national drag series to FE?

Apples to oranges, drag races are under 10 seconds, so battery is not a problem when that´s the main challenge for any other electric racing series

[MOWOG]

Perhaps we can all agree that battery powered cars will not make their mark in endurance racing any time soon?

Actually, there is a group in the US who are bringing electric racers to the track and competing against gasoline powered rivals - and winning! You can check it out at this link: http://evsr.net/

[theblackangus]

I agree with all of your points except this one. I'm not one to complain about sound, yeah I like the sound of a good v6/v8/v10/v12 or even the quiet thrum of the desiel lemans prototypes. I liked the sound of the Formula E cars from the initial youtube videos. However when I watched the race on a good TV with good speakers the sound was overwhelming (much like being next to a 20k rpm v10 when its reving, but just quieter) to the point where it just hurt my ears. Certain camera/mic positions were ok, but many were very harsh on the ears the way a non-electric motor just isn't. I don't mind quiet cars I mind the harsh sound.
I hope either via sound engineering (in production) or engineering of the actual electric motor itself the sound can be made less harsh.

I´m not sure if I get it, but I think you mean the tone was too high and even when it was not high in volume it was harsh on your ears?

Did you test with different modes? There usually are different modes: spectacles, sports, cinema, music... and they handle different tones in different ways

They must be using sensible microphones to record as much of the sound as they can, not an expert about sound, but that could be a problem. When you hear something through TV low tones almost dissapear, while high ones are much easier to replicate. I guess they (TVs) also need some experience for a good FE broadcasting, there were many things they could have done much better, as camera positioning

Yes the tone would get very harsh in different camera views. It was only harsh when there were multiple cars, a single car didn't seem to generate the bad sound. I think Mnzo (sp) above may be right, it could be the reduction gears, and something about the high end sound there and when multiple cars are all generating that at the same time.
For the avr - I tried a couple different modes but the same harshness is there (even with THX roll-off) so its something below 16k hz.

And to be clear it wasn't like I wanted to put ear-plugs in (ie not like standing next to a 20k rpm V10) but it had that same effect on my ear drums just to a lesser degree. It was disharmonious.

Im surprised Im the only one who has thought this. Im going to have to pass sound to my TV and see how it sounds from the tiny tv speakers.

[Pierce89]

I enjoyed it, I took it for what it was, don't compare it to other racing categories unless you can point me in the direction of another fully electric series.

The US has the NEDRA. Its electric drag racing.

And you want to compare a national drag series to FE?

Apples to oranges, drag races are under 10 seconds, so battery is not a problem when that´s the main challenge for any other electric racing series

Wow! If you read, my whole point is that current tech is much better suited to drag racing. At the moment full EVs aren't suitable for racing. They should've gone for series hybrids more efficicient and less complex than a parallel hybrid. A series hybrid would still only have electric drive, you just use a low constant rpm ICE to generate electricity.

[Andres125sx]

Wow! If you read, my whole point is that current tech is much better suited to drag racing. At the moment full EVs aren't suitable for racing. They should've gone for series hybrids more efficicient and less complex than a parallel hybrid. A series hybrid would still only have electric drive, you just use a low constant rpm ICE to generate electricity.

I read it... now

And agree that way they´d be faster and races could be longer, but then they wouldn´t push battery technology, and that´s one of the main point of FE. If you use an ICE as a generator the battery then play a secondary role, actually I think they could use capacitors for that better than a battery

About your "aren´t suitable for racing" statement, have to disagree. I watched a race past weekend with full EVs so they´re suitable. Maybe you mean they can´t be compared with ICE racing, then I agree but again, that has never been his goal... yet

[FW17]

NEDRA sounds impressive. The kind of machinery that these guys bring out (all EV's are complex when involving power electronics) from a handful of garage people is impressive. Compare that with the spec series of FE which had some serious development partners with serious budget NEDRA has outdone itself.

[FW17]

[Richard]

How much do they weigh? I can't help thinking that splitting those into say 2 or 4 units would enable a "refuelling" pitstop rather than swapping cars.

[Andres125sx]

How much do they weigh? I can't help thinking that splitting those into say 2 or 4 units would enable a "refuelling" pitstop rather than swapping cars.

RESS
A Rechargeable Energy Storage System (RESS) is a system that is designed to propel the car via the electric motor. In order to comply they must be:
- FIA Standard
- The maximum weight of the Battery Cells and/or Capacitor of the RESS must not be higher than 200kgs
- All Battery Cells must be certified to UN Transportation Standards as a minimum requirement

http://www.fiaformulae.com/en/guide/car.aspx?page=1334

Problem splitting batteries is power density depends on capacity. If you want same power from a smaller pack the battery need to be discharged at a higher rate, so you´re pushing the battery harder. If the battery is being used at the max discharging rate, splitting the battery you´d be forced to split the current drawn and power too

Don´t know what´s the discharging rate of those batteries tough, because the average is 2C (they last 30 minutes) and there are batteries with up to 65C discharging rate in the market, so they could probably push them harder.

But I think they´re being really conservative for first seasson. Imagine if some batteries fail half seasson.... That´s what I´d do at least, start with something you know will work for sure, and from that point you can push each component next seassons depending on how did they handle the seasson

[Waywardism]

Watched it last night, have to say I found it so boring that after the pit stops I fast forwarded it to the end. The cars look so slow but also quite a handful and there was only one guy who could manage to overtake, and I think that was only because he was using full power. I don't think the track helped either, all straight right angles and stupidly tight chicanes. They need to make tracks with at least one mid-high speed corner and/or a long enough straight that we might see some slipstreaming.

The coverage was awful aswell. Presenting the show from a studio just makes it seem like a mickey mouse event for a start. And what the hell was that about the music? Ok so electric cars just whine a lot so playing music can sort of compensate for that, I get that. They played it so quietly though that it just annoyed me. Either turn the volume up, or scrap the music altogether and turn up the mics on the cars.

Prost should never be allowed on a racetrack again. Does a brilliant job right up to the very last lap and then turns in to someone on a straight. Dangerous idiot.

[mzso]

Electromagnetic braking is great if you can find somewhere to send all the electrical energy instantly.
Wheel motors increase unsprung weight.

Sorry I did not reply earlier about rim motors, I am still looking.

I'm wondering about how much power would it be? Significantly more than what a motor's (which was only designed with propulsion in mind) peak power would be?

Yeah unsprung weight might be an issue unless they trim it down a lot. (Maybe not much with active suspension?)
They could also connect to the wheels with a simple driveshaft. (Probably problematic in the front.)

Electromagnetic braking.....

I wonder how effective it is. If it works, that´s the future hands down.

Regenerative braking at the four wheels and get rid of brake disks, wich are the best way to waste tons of energy


But I´m not sure if electromagnetic braking is enough to stop a car similar to brake discs, or if it will be able to be similar some day wich is the important point.

I suspect there's a chance the desired braking power might exceed what's needed for propulsion. Though maybe they can handle it for short bursts.
Also most logical would be to combine it with some more modest friction brakes.

Well if "someday" we get zero resistance conductors then it certainly will be as good. :

[mzso]

As far as I know efficiency loss from a gearbox is anything but "slight". It negates anything efficiency wise and takes a bunch more.

I disagree, an electric motor efficiency map is anything but flat (e.g. http://www.neweagle.net/support/wiki/do ... /PP150.pdf), which is where the multispeed gearbox comes in (by allowing the motor to run in the "highest efficiency zone" for more of the time, despite the fact that the gearbox introduces an additional inefficiency.

I'm aware. (see also: 1 2 ) You're missing the point. I didn't disagree with that. What I say is that gears, especially gearboxes waste a LOT of energy. I doubt it can be close to being less wasteful than a well designed, direct drive motor.
Also racecars accelerate very quickly, and keep high speeds as long as they can. The low efficiency regions are only in affect few percentage of the time. At moderate to max speed they're have good to great efficiency.

Whilst it is true that they are getting lighter, I've yet to see an application where it is not better ( in terms of weight and size) to use a higher speed motor and gearbox combination, (even for in-wheel applications):-

• RC planes (as per Andres125sx post)

• Starter Motors (one of my previous posts; look up Brise starter motors for info)

• Formula Student (AndyL's previous post)

• Formula E (Let's not forget that Williams and McLaren, who are responsible for the arrangement used on Formula E, are not stupid).

• Drayson-Lola (one of my previous posts)

In weight and size it's probably inherent, by laws of physics that they are heavier since gears multiply torque.
But, they could be made light/small enough for it to be insignificant and/or the positives outweighing the negatives.
Also it would be one of the points to develop/perfect direct drive which didn't get much attention in the past. Which contributes to their scarcity.

[Andres125sx]

Electromagnetic braking is great if you can find somewhere to send all the electrical energy instantly

Capacitors?

Wheel motors increase unsprung weight.

They don´t need to be at the wheel, a drive shaft solve it, specially if you still need brake discs. If not a drive shaft would be problematic to apply too much braking torque, but if it´s not the case why not?

Sorry I did not reply earlier about rim motors, I am still looking.

No more clues about what are you looking for exactly?