yes they are going to rethink them aren't they. Perhaps 48v can work if the bolt the battery to the motor, or use an aluminium chassis as the conductor. They are very different to drive too, and service and everything, braking... and it's all easier to automate, i love that Tesla SummonBig Tea wrote: ↑09 Nov 2019, 23:17I was thinking similar, wire lengths are going to be noticeable resistance. I like it though.
Something I notice lately is people are rethinking about how things will work. So far it has been re using existing tec, sort of like having a horse on a tread-wheel in the car with you in an early car.
48 Volts is the power territory of established hybrid's ICE architecture/technology ie physically parallel-installed gens or MGsizzy wrote: ↑09 Nov 2019, 22:38Cool! but 48v must mean a zillion amps and huge fat cables? isn't cabling why F1 runs at 1,000v?Brake Horse Power wrote: ↑09 Nov 2019, 20:54Nice one!
Here is another promising company called Volabo. They are developing high power output electric motors at 48volts. This is obvious a lot safer than current high voltage systems and it allows them to work with cheaper components. Also their motor doesn't need rare earth metals and as icing on the cake they have developed a continuously phase shifting technology. So they have the benefits of several types of phase motors combined in one giving a greater efficiency.
https://youtu.be/1UBJqDGGRRU
https://volabo.com/
well a Renault Zoe battery puts out 345V, so where does a 48V 'high power' motor fit in, in the EV world? is my question. presumably it does obviously. but my elementary physics says if they want 100kW of power for the car at only 48v that'd be 2,000 Amps!Tommy Cookers wrote: ↑10 Nov 2019, 13:4048 Volts is the power territory of established hybrid's ICE architecture/technology ie via belt-driven generators
territory where there's a conventional relationship between power and current
where is Volabo claiming anything different ?
for higher powers no-one is going to replace hundreds of Volts and tens of Amperes with tens of Volts and hundreds of Amps
people here are failing to appreciate that these are not 'on-line' machines (our traditional experience)
they are machines that work by being fed moment-by-moment shaped, sized, and timed pulses custom-made in the moment
afaik the making of said pulses will always be better served by relatively high voltages and relatively low currents
(the same applied to high current brushed DC machines ie it's brushes not conduction issues that reduces efficiency there)
the EM here is like an ICE but the functions of throttles, cams, and valves are remote and connected by cable to the EM
btw even if we call these AC machines the basis of these functions is internal DC
the driver of this efficient high power/controllability was advances in power electronics FETs etc around 35 years ago
the parallel advance in magnet material eg rare earth magnets is less important and somewhat dispensable
there's nothing new about reluctance motors - aren't Tesla now using one of the various possible types ?
there's nothing new about patents for commercial manoeuvre and benefit
The i3 had one and they dropped it, for less weight and more range. Tho you'd cruise on the battery and have the petrol motor just as a backup, is the conceptFW17 wrote: ↑12 Nov 2019, 08:34Why are range extenders not popular?
A typical ev like a model 3 or Zoe cruises at 15kw/hr. Cant a range extender be directly coupled to as a power source to the motors rather than batteries when cruising, while keeping the batteries for start and sudden power requirements?
Cant 15kw be provided by a small generator unit running at modest rpm and high efficiency?
https://upload.wikimedia.org/wikipedia/ ... dserie.png
I would say that BEV should be limited to 100 - 150 mile range for passenger cars, while regulators concentrate efforts to bringing all commercial vehicles to the BEV platform.izzy wrote: ↑12 Nov 2019, 11:49The i3 had one and they dropped it, for less weight and more range. Tho you'd cruise on the battery and have the petrol motor just as a backup, is the conceptFW17 wrote: ↑12 Nov 2019, 08:34Why are range extenders not popular?
A typical ev like a model 3 or Zoe cruises at 15kw/hr. Cant a range extender be directly coupled to as a power source to the motors rather than batteries when cruising, while keeping the batteries for start and sudden power requirements?
Cant 15kw be provided by a small generator unit running at modest rpm and high efficiency?
https://upload.wikimedia.org/wikipedia/ ... dserie.png
I think in practice it's that people don't travel as far as they think, mostly, so for all the anxiety range isn't actually much of an issue. If you do really long journeys you just don't get an EV, yet
why would you limit car range? they have to develop EV's generally, to get enough range for commercial vehicles to be delivering or whatever all day. Cars are what give scale - vital ingredient!
I see what you mean but you can't design to the average. Average means half the journeys are longer (or more, depending on the distribution), and it doesn't tell you the longest journey people want to allow for, which is a different thing altogetherFW17 wrote: ↑12 Nov 2019, 18:41The average british driver drives 32 miles a day, why have cars with battery packs so large?
What is the point of chasing a 300 mile range when the average usage is about a 10th of that?
Batteries are a limited in supply, needed for the entire world, why should they be installed for no purpous ? It is better used in commercial vehicles (cabs, vans, buses and lorries) that predominently run on diesel
Same reason nobody builds a car with a 4L fuel tank.
Fuel tanks don't weigh as much as unused batteries though. Not that I think a small capacity electric vehicle will be viable for enough people to justify it,