The General Motors Voltec propulsion system has been named the Technology Of The Year by the Automobile Journalists Association of Canada.
The components that make up the driveline of the Chevrolet Volt got the nod from the judges, AJAC members who are engineers or regularly write technical articles for Canadian newspapers and websites.
The Voltec drivetrain narrowly edged out Mazda’s SkyActiv gasoline engine, while General Motors also had the third-place finalist – the eAssist system offered in the Buick LaCrosse.
AJAC’s Technology of The Year Award is given annually to a new or vastly improved technology that is deemed most significant to Canadian consumers. Manufacturers submit their entries in October where the judges narrow the list to a manageable number. The criteria used is that the technology be one that has such significance it will likely gain widespread use throughout the industry.
The Voltec propulsion system is made up of a number of inter-related components that allow the Volt to operate as a purely electric car most of the time, while eliminating the “range anxiety” associated with electric cars. The system allows the Volt to run as a pure electric until the battery reaches the stage where a recharge is required. But instead of having to stop and find a power source, the Volt’s tiny gasoline engine comes to life to generate electricity to recharge the battery.
The Voltec electric drive consists of a pair of a battery pack, inverter, 150-horsepower traction motor, 75-horsepower generator, planetary and final drive gears, a trio of clutches and a differential. There is no transmission. It has four operating modes that cover the full range of speeds and needs.
The gasoline engine in a conventional hybrid is called upon frequently to augment the power from the electric motor and battery, which is never allowed to discharge. The engine operates over its full rev range as in a conventional car. In a plug-in hybrid, the engine is also used frequently to supply power and the battery is allowed to partially discharge.
With the Voltec system, the electric motor is the sole source of propulsion during the entire EV range. The engine is not used at all for propulsion other than a very brief time at maximum discharge. When it does come into play to recharge the depleted battery, the engine operates within a very narrow rev range, where it is most efficient.
Based on data collected via OnStar from more than 5,000 Volt customers, two-thirds of their driving is in electric mode only. They average 1,600 kilometres between fill-ups of the 35-litre tank. Most visit a gas station only once a month and this real-world experience equates to about 2.0 litres/100 km. GM has already announced plans to use this system in a number of other vehicles.
The runner-up, Mazda’s SkyActiv gasoline engine, has a number of advances that allow the conventional gasoline engine to run on regular fuel at extremely high compression ratios. The result is hybrid-like fuel economy; the first iteration of the new engine and technology appears in one trim level of the 2012 Mazda3. Due to space limitations in this existing car, it does not have the complex exhaust system and full slate of SkyActiv features that will be introduced in the 2013 Mazda CX-5 compact crossover coming to market in the spring.
Third place went to GM’s eAssist system, which consists of a 13-kg battery, electronics and a motor generator that supply supplemental power to a conventional engine. The system allows idle stop, captures energy to recharge the battery during deceleration and braking and reduces engine and driveline losses.
The other finalists were:
-Mazda’s SkyActiv automatic transmission, which uses numerous advances to allow a conventional automatic transmission to replicate the performance and fuel savings of CVT and dual-clutch transmissions without their shortcomings.
-The Magic Sky control glass roof in the 2012 Mercedes SLK, which uses nano-particle technology and electricity to align or misalign particles within the panel to block or let in light.
-Ford’s Active Park Assist, which can parallel park an automobile in extremely tight spaces with no driver steering input required.
-Chrysler’s Multi-Air valve control system used in the Fiat 500. This hydraulic system replaces conventional valve springs and allows much stricter control of intake air.
-Toyota/Scion airbag innovations: a number of airbag applications that allow this diminutive car to offer exceptional occupant protection.
-Toyota/Scion packaging innovation” everything from a tiny air conditioning system to flipping the differential to gain space.
-Toyota Prius V Pitch and Bounce Control: a method of using fine control of the electric drive system to reduce fore-aft motion.