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New Semiconductor Could Improve Vehicle Fuel Economy By 10 Percent
cartechboy writes: "Automakers are scrambling to increase vehicle fuel economy every year as regulations increase, so when an automaker finds a way to possibly increase fuel economy by 10 percent with one new part, that gets some attention. Today that automaker is Toyota, and the part is a new semiconductor. Toyota's power control units (PCU) in its hybrids use semiconductors to govern the flow of electricity between the battery and the electric motor. Unfortunately, they're also an electrically restrictive component. Toyota says the PCU accounts for a quarter of the total electrical power losses in a hybrid drive system, and semiconductors alone make up a full fifth of the total. Reduce electrical losses through a semiconductor, and you can make your hybrid system (and therefore your car) more efficient. Toyota has done this, in theory at least, using a new silicon carbide material for its semiconductors, rather than a standard silicon unit. The future could be shaped by individual parts, and this new semiconductor tech is one piece of that puzzle."
Amazingly content free press release. No clue what these devices are. This is just fluff reporting with no details.
[foxworthy] /.er
If you have a favorite local semiconductor manufacturer, you might be a
[/foxworthy]
"Never let your sense of morals prevent you from doing what is right" - Salvor Hardin
10%+ increase in efficiency gets automakers' attention? No it doesn't.
If they were really serious about fuel economy, they'd go to work on the aerdynamics for starters. Current vehicles have far too much air resistance. And actually they know this. They don't improve the aerodynamics for several reasons. They're afraid the public will think it ugly, and they think it will cost more to manufacture. One of the simplest improvements are skirts for the rear wheels. Every time it's been tried, the public rejects it. Another easy improvement is smoothing the underside. But that costs more, and not just during manufacturing. It also increases maintenance costs as it's one more item that has to be removed to service much of the car.
Intellectual Property is a monopolistic, selfish, and defective concept. It is "tyranny over the mind of man"
It has a faster recovery time too. More MOSFET's won't change that.
Faster recovery time means they can run at a higher frequency and use smaller inductors to convert the voltage. Lower inductance means less copper, less resistance. So not only is there less loss in the transistor, there is less loss in other components.
If you keep adding more MOSFET's, you need to keep increasing the drive current or they'll switch slower.
While a MOSFET is switching, the resistance can be quite high. Even if faster silicon carbide transistors had the same Rds, there would be lower losses during switching.
Tesla claims an overall efficiency of 88% for their cars, from grid to wheels.
Looks like Toyota has produced the pinch-channel Class I V transistor in SiC with no minimum offset / gain.
Seriously, holy grail for current steering.
Can't find the vendor of the raw SiC so no idea about Delta-V / Delta-I limits but looks very good
10% net reduction in loss.