Chevy Volt Surprise

Don Sherman

Cleanse your mind of what you think you know about the Chevy Volt. It is not just an electric car. It does not operate as implied by GM for the past three years. Now that production has begun and customer deliveries are about to commence, the secrets are out. A true explanation of exactly what makes the wheels turn can finally be told.

According to Larry Nitz, GM's executive director of electric and hybrid powertrain engineering, this bit of bait and switch was necessary to safeguard the intellectual properties necessary to make the Volt a true technological leap forward. During the past three-plus year of engineering and development, GM applied for several patents to protect many small and large inventions. Those patents have been issued and Nitz is finally comfortable speaking frankly about what's under Volt's hood.

The Volt concept car, which debuted at the 2007 North American International Auto Show in Detroit, had an AC motor connected to and permanently driving the front wheels. A turbocharged 1.0-liter 3-cylinder gasoline engine powered a generator which supplied current to the drive motor, but only after the onboard lithium ion battery pack was depleted. This system, which GM called E-Flex, provided an electrical connection between the two portions of the powertrain but no mechanical connection.

When the evolution of the promising concept into a practical production car began in earnest, GM engineers immediately ventured beyond E-Flex. Maintaining a strong emphasis on electric propulsion, they added parts and increased the role of the gasoline engine. The finished product-now called Voltec--is much closer to a Toyota Prius than a Nissan Leaf. Volt is the first extended-range electric car, as advertised, and more.

Secret Gears and Clutches!

1. The previously undisclosed heart of the matter is an automatic transmission consisting of one planetary gear set and three electronically controlled, hydraulically activated multi-plate clutches. This ingenious transmission efficiently blends electrical and mechanical attributes to drive the wheels with utmost efficiency. All Volt powertrain components-two electric motor-generators, the 1.4-liter 84-hp gasoline engine, the aforementioned transmission, and a final-drive differential-are bolted together in a single unit to save space and weight and to optimize NVH characteristics.

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If Japan didn't slap outlandish tariffs on made in USA products, I'd say go ahead and get your inferior Prius. Until that changes, why not get the better car - the Volt (you may go months without buying gas at all).
One vehicle missing in this discussion is the Ford FusionHybrid, starting price 28,100.While I located one loaded Ithink you could get less butthis one has all the bells and whistles for 32.915. And has EPA 41 City/ 36 HWY mpg.
In point of fact, the primary AC motor always provides the primary motivation. When the car gets above 70 mph the planetary gears are unlocked and the generator/secondary motor drives the planetary gears, primarily to provide an effective gear reduction to slow the primary motor into a range in which it is more efficient. While undeniable that the generator/motor provides its own torque to the effort to drive the wheels, in this application this is largely a side benefit.Because the engine drives the generator/motor as a generator when the batteries get below 30% charge, above 70 mph the engine is connected to the planetary gears through the generator/motor if the battery charge is too low. While undeniable that, under 1 specific case the engine assists the electric motor in driving the wheels, it is largely a side-effect of the fact that GM borrowed the planetary "transmission" from its own mild hybrid and did not design a completely new "transmission" to always keep the primary AC motor at optimal RPM.
Anyone who buys any hybrid to save money on gas is an uninformed consumer. If you want to have reduced emissions and use less gas for non-economic reasons, fine. Whether you're talking about a Prius, Volt, Leaf, whatever; a small 4 cylinder sedan like a Corolla or Civic is the most cost effective option.After incentives ($7.5 to $9k), a Volt may be competitive with a $28-30k sedan. Whether the extreme cost of battery replacement in 8-10 yrs will affect you should be considered before buying. I have a feeling that GM will have a gov't backed 2,3, or 4 year lease program.
So, you think people will go to the gas station instead of just plugging it in at night??
--All of this assumes people will hassle with plugging-in their Volt. Chances are, they will drive it like a pure-hybrid (which the Volt is not).Better deal is a $23K Prius - That 10 grand in savings will pay for 25 years of gas and you don't have to hassle with plugging-in the Prius.--

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