Eaton Supercharger Debuts in China on Three New Chery Engines
25 April 2010
Eaton Corporation’ superchargers will make their debut in China on selected new engines on three vehicle models from Chery Automobile Co., Ltd., the country’s leading independent automaker: Chery 1.6S Tiggo, 1.3S A3 and Riich 1.3S G3. This latest Eaton supercharger application will be the first on a Chinese-produced vehicle.
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| Eaton supercharger. Click to enlarge. |
Eaton designs and manufactures precision Roots-type positive displacement superchargers for highly specific automotive applications. The Roots-type supercharger consists of two counter-rotating meshed lobed rotors. The rotors trap air in the gaps between rotors and push it against the compressor housing as they rotate towards the outlet port. During each rotation, a specific fixed amount of air is trapped and moved to the outlet port where it is compressed.
Its quick response eliminates the lag of many competing systems, and it allows vehicle manufacturers to replace larger engines with smaller, more efficient engines that provide better fuel economy and reduced emissions.
Fuel savings and emission reduction are the new themes for China’s auto industry. We are pleased to cooperate with Eaton and bring these high-performing superchargers to the China market. Chery is continuing to leverage global resources and is making great strides in building core technological competitiveness, as well as actively following government policies to reduce greenhouse gases and emissions.
—Dr. Zhu Hang, vice president and Dean of Engine Engineering & Research Institute, Chery Automobile Co. Ltd.
Eaton is the worldwide leader in supercharger solutions for small displacement engines for customers in markets around the world. Eaton supercharger technology has been selected by numerous premium global automakers and can be found on these vehicles: Audi A6, S4 and S5, Chevrolet Corvette ZR1, Cadillac CTS-V, Volkswagen Touareg Hybrid, Porsche Cayenne S Hybrid SUV, Jaguar XKR, XFR, XJR and Range Rover Sport and a version of the fourth-generation Nissan Micra.
I believe supercharging more easily provides a much better imitation of a larger engine than turbocharging because it provides power at very low engine rpm and has no lag (as long as it can be activated quickly and unobtrusively).
Another big advantage is that it can be “quick; - less of a system design challenge.
It also adds a little less heat so that, at low boost or short boost (as in drag racers), an intercooler is optional. Also the exhaust system is kept simple.
This is offset by lower fuel efficiency (vs. turbocharging) when active because of the significant shaft hp required and the fact that they do not recover the “free” exhaust energy - which is even higher when boost is active.
I assume these are controllable ? (on – off; - another complication and harshness) so they don’t spin when unneeded (like, most of the time) nor add drag and increase throttling losses.
So maybe if the “EPA driving cycle” (and most real world driving) did not involve operation with boost ON, such a system might be very competitive in providing that important “perceived quality” that comes with being able to effortlessly accelerate, if and when you need to; while still providing the mpg boost of downsizing.
Posted by: ToppaTom | 25 April 2010 at 08:30 AM
Selective access to more power (when needed ONLY) is very advantageous. Why carry a huge 500 hp V-8 under the hood for less than 5% of the time (for accelerations) when only 100 hp are required for the other 95% of the time. Smaller engines that can selectively produce 100 hp (or less) and 300 hp (or more) on demand may have a future and would consume less fuel.
Posted by: HarveyD | 25 April 2010 at 09:16 AM
There might be a good link with a small IMA size motor able to recover braking energy into a supercapacitor and then use an electric supercharger to boost the engine.
Although it would be better to use the IMA to move the vehicle up to a slow speed then use engine with the boost from '2nd gear'
Posted by: 3PeaceSweet | 25 April 2010 at 10:27 AM
Combined electric super-turbocharger is the way to go, IMHO. Eliminate turbo lag by spinning the blower with electric power until the exhaust pressure catches up. More complicated, but significantly more fuel-efficient than a mechanical blower, I think.
Lighter vehicles with downsized, forced-induction, direct injection ICEs are the cheapest near-term solution to reducing fuel consumption and carbon emissions (apart from telecommuting, bicycles and walking).
Posted by: Nick Lyons | 25 April 2010 at 02:16 PM
The problem with occasional access to more power is that it is not free - regardless of whether it is a huge, cheap V8 or an expensive electro-turbocharger with batteries.
Posted by: ToppaTom | 25 April 2010 at 05:16 PM
@TobbaTom:
As you no doubt are aware, turbocharged ICEs use heat (energy) that would otherwise be wasted to spin a turbine that drives a compressor that forces air into the cylinders, allowing a lighter, smaller engine to produce the power of a larger, heavier one. The energy is free, in that sans turbo, that heat just goes out the tailpipe. And by allowing the engine to be downsized, the vehicle becomes lighter, multiplying the savings. Adding an electric motor to occasionally spin up the turbocharger so as to avoid turbo lag takes very little energy compared to the gains one gets from the turbo.
The point I was trying to make earlier is that supercharging gives you the benefits of downsizing: lower weight, lower frictional losses from fewer cylinders, etc. Turbocharging gives you all of that plus it turns exhaust heat into mechanical work instead of adding another accessory load to the engine. Electric boost for the turbo is just a way to address turbo lag, making the engine more responsive and the vehicle more 'driveable'.
Posted by: Nick Lyons | 25 April 2010 at 05:47 PM
They're still not free.
Whenever hp/lb is the goal, the US is typically large displacement and Europe was high rpm, exotic valve trains.
Since at least the 60s, Turbos or superchargers were constantly at the fringes, but they were not mainstream because they were expensive, not free; dollar wise or complexity wise. They were very capable, but expensive.
Maybe this time, with fuel economy the goal, maybe not.
Posted by: ToppaTom | 25 April 2010 at 06:41 PM
@ToppaTom:
I thought we were talking about efficiency, not capital cost. Certainly, smaller, boosted engines are more expensive per pound, so capital cost may be higher than a simple pushrod V8. However, overall vehicle efficiency can be made much better using these smaller, lighter, more efficient engines.
Even setting consideration of carbon emissions aside, higher fuel prices and CAFE standards are tipping the balance in favor of smaller, more sophisticated, more expensive, more efficient engines.
Posted by: Nick Lyons | 25 April 2010 at 08:49 PM
In a mild HEV, it is possible to use an electric-assist turbocharger also as an electrically-coupled turbo-compounder for even higher efficiency gain during cruise. This will help justify additional expense for the electrical assist system and the turbocharger.
An electric motor-generator stands between the compressor and the turbine wheel. In supercharging mode, the electric motor-generator powers the compressor while waiting for the turbine wheel to spool up. In turbo-compounding mode, the compressor is declutched from the motor-generator, and the turbine powers the motor-generator to produce electricity. Excess electricity can be fed to another electric motor-generator in the drive train to add power to the wheels. The drive-train motor-generator can also serve as energy recuperator during vehicle braking, and to allow the engine to be shut off during stop and low-speed cruise in order to save fuel.
Posted by: Roger Pham | 25 April 2010 at 10:29 PM