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Tesla shares 48V architecture with other automakers

electrek.co

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Re: Tesla shares 48V architecture with other automakers

#401

Post by KaiserPro »

londons_explore wrote: post #337
KaiserPro wrote: post #104

Earlier quoted context omitted.

if you're switching 48v, you'd want a mosfet rated for way more than 50v. On a car you'd want 200% headroom at least.

With totally uncontrolled bus capacitance and inductance, sure. But when you're using the same bus for Comms you need to have control of high frequency spikes, and low frequency spikes are easily handled by a bidirectional DC/DC. Therefore I could imagine peak to peak ripple on this bus to never exceed 1 volt.

> Therefore I could imagine peak to peak ripple on this bus to never exceed 1 volt.

https://www.quanterion.com/wp-content/uploads/2014/09/MIL-HD... disagrees.

Re: Tesla shares 48V architecture with other automakers

#402

Post by arghwhat »

jdewerd wrote: post #338
DannyBee wrote: post #272

Earlier quoted context omitted.

48V has been considered for automotive for decades. The problem was not know how. It simply has never been worth it before to retool things in practice. It's also electrically a lot more noisy. The limit of what is considered low volt is like 60v or something.

It was never worth it to retool for decades ? Or was there a pathological lock-in between suppliers and manufacturers that prevented even the most obvious innovations from happening if they required any amount of coordination?

24V is common in trucks, and yet never made it to regular cars because there was never sufficient reason.

Using a higher voltage is not an innovation (it's an obvious change, and we've gone from 6V to 12V to, in some cases, 24V already) - rather it's just a slight efficiency improvement in largely non-critical systems, with not a lot of incentive to take on the cost of transition.

In a a personal ICE vehicle, the only real significant power was to the starter motor and from the generator, and the distance there was short so the copper didn't really matter and thus no one cared for 24V - unlike industry where you might have significant aux systems. With EVs, you have heat pumps and brake boosters on the auxillary power, so you now have a stronger driver for conversion.

Even within 12V, you'd get a larger weight reduction from not carrying an aux battery, and just feeding through a converter from the HV system.

Re: Tesla shares 48V architecture with other automakers

#403

Post by panick21_ »

imp0cat wrote: post #336
panick21_ wrote: post #72

Earlier quoted context omitted.

I expect Tesla to still have a few components like that in the car.

Isn't that the point of the article though? That they run everything on 48V?

I think all the wires/communication are but some of the devices attached are lower then 48V, some very low voltage, and some might be 12V. We will see when its taken apart.

Re: Tesla shares 48V architecture with other automakers

#404

Post by panick21_ »

avalys wrote: post #397
DannyBee wrote: post #272

Earlier quoted context omitted.

48V has been considered for automotive for decades. The problem was not know how. It simply has never been worth it before to retool things in practice. It's also electrically a lot more noisy. The limit of what is considered low volt is like 60v or something.

Mercedes-Benz has been using 48V systems since 2016. https://paultan.org/2016/10/31/mercedes-benz-reveals-first-d... This dynamic, where Tesla "announces" something that the rest of the industry has been doing for a while anyway, and a bunch of star-struck enthusiasts and stock manipulators tout it as an example of Tesla' "super smart innovation", is getting tiresome.

That's a complete misunderstanding of what Tesla did. Having a component in the car that is 48V and having the whole car being on a 48V PoE architecture are totally different things. The sad part is that these company actually have the beginning of a 48V system but never actually pushed threw and did it all.

This is like when SpaceX landed a first stage and everybody was like 'DC-X did it SpaceX did nothing new'.

There is a reason lots of people, including experts are exited of what Tesla did here.

Re: Tesla shares 48V architecture with other automakers

#405

Post by panick21_ »

Closi wrote: post #399
hef19898 wrote: post #353

Earlier quoted context omitted.

Since car manufacturing, and design, wasn't held back at all by something like auxiliary current, the reason more likely was people not wanting to waste energy to improve on something that is working just fine for everyone.

Well according to Tesla it wasn't working just fine for everyone - they have been able to massively simplify their internal wiring. Classic example of legacy automakers happy to maintain the status-quo because it is easiest, while the new kid on the block is pointing out that things don't have to be the way they are just because they are that way.

Its the same with aluminum casting. The car makers used the technology once in a while in some specific parts, Tesla was like 'why not make half the car out of one casting'.

Tesla worked closely with a supplier, did lots of its own research and development and continue to work with a supplier to make the technology better over time.

This was considered stupid at first. This is now very widely copied. First automakers from China copied it. And now others are copying it as well. Even Toyota (who everybody believes are some kind of gods of manufacturing) are copying this now.

If you have been doing something one way for long enough, going into a radically different direction is hard. Your whole workforce knows about welding steel sheets together, and nobody knows anything about casting. Your whole workforce knows about V12 and the ecosystem for that.

Its hard to fundamentally change how you do things when you are producing millions of vehicles a year.

Re: Tesla shares 48V architecture with other automakers

#406

Post by panick21_ »

avalys wrote: post #398
szundi wrote: post #368

Earlier quoted context omitted.

That’s what Elon said, no innovation, just made the step

[flagged]

As usual whenever Elon is involved people turn of their brains just so they can not admit that Elon or his companies did something well.

Nobody says this is the first time V48 has ever been used for anything. That literally just missing the point.

The point is that the whole architecture of the car will use PoE 48v.

And if you go and take apart these Mercedes cars you will see that the waste majority of all of the devices and the wiring use the exact same 12v architecture that all the ICE cars also use.

Re: Tesla shares 48V architecture with other automakers

#407

Post by dade_ »

NotYourLawyer wrote: post #270
elp wrote: post #11

48Vdc is supposedly the highest voltage that is still considered safe. ( https://electronics.stackexchange.com/questions/267789/how-s... ) It certainly sounds like a smart move on the copper savings alone.

With wet hands, even 48v hurts .

On my tongue, 9V hurts. There is pain, but no harm.

Re: Tesla shares 48V architecture with other automakers

#408

Post by wil421 »

Closi wrote: post #399
hef19898 wrote: post #353

Earlier quoted context omitted.

Since car manufacturing, and design, wasn't held back at all by something like auxiliary current, the reason more likely was people not wanting to waste energy to improve on something that is working just fine for everyone.

Well according to Tesla it wasn't working just fine for everyone - they have been able to massively simplify their internal wiring. Classic example of legacy automakers happy to maintain the status-quo because it is easiest, while the new kid on the block is pointing out that things don't have to be the way they are just because they are that way.

Legacy automakers have no need for a 48v system. Most vehicles have an ICEs and they will for the next decade(s) as EV and PHEV adoption rises. 12 years is the average age for cars in the EU/US.

Why would they upgrade a system when they don’t need to? Tesla can be a front runner and companies like Bosch will start creating 48v parts as EVs become more popular for legacy auto to use.

Re: Tesla shares 48V architecture with other automakers

#409

Post by codeulike »

Moto7451 wrote: post #189

Audi also has a 48v architecture in use for mild hybrids like my SQ5. This is an older article but explains it well https://www.greencarcongress.com/2017/06/20170602-audi.html My 2021 is fully 48v except for an inverter for necessary 12v circuits (like cigarette outlets and the jumper pins) and a small motorcycle battery that is used for minimal 12v functionality. The mild hybrid battery is under the rear seats and s…

Its not that same, that Audi still had a 12V system because all the commodity parts (control units, interior lights) are built to run on 12V. What Tesla are doing is getting rid of 12V entirely so that every little window raising motor or interior light or actuator to move the seats is running on a 48V system.

Re: Tesla shares 48V architecture with other automakers

#410

Post by codeulike »

intrepidhero wrote: post #5

Why would a car need a 48V system for accessories? In general the things a car's 12V system powers have gotten less power hungry over time (LED's, heat pump) and in particular, an EV loses the highest power electrical device on the 12V bus, the starter. The typical equipment used for the entertainment and control systems are going to be much more available with 12V supplies, just because that's the industry standard.…

As well as switching to 48V they are going to use Ethernet cables for most of it (PoE). So at the same time they get rid of the CAN bus wiring and have everything running on ethernet for communications and power, which means a LOT less wiring because with CAN bus every device needs its own wire but with Ethernet its much easier to have 'hubs' that channel communications and power on to other devices.

https://twitter.com/cybrtrkguy/status/1731658374775771297?s=...

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