May 29, 2012 – Vol.17 No.11
RETHINKING ELECTRIC CARS - PART 10.
by Bruce Mulliken, Green Energy News
Developing new cars is an expensive undertaking. Cars are the sum of their parts. There are thousands of them in cars. According to one source (Toyota), counting every nut, bolt and screw the average car has about 30,000 parts. Whatever part or component that can't be used from another or previous model, a new part has to be specially designed and engineered to fit the new vehicle. It doesn’t end there. Once the new part is designed then production tooling has to be developed and crafted to manufacture that part for the new model car. Somewhere in there testing and documentation are included for each new part and producing it in a factory.
Fifteen years ago, the last time I talked to an automotive engineer about this, the rule was that the average price to develop each new part number was $50,000. That figure is certainly higher today. Some parts, like the plastic switch button to operate power windows, cost less. Others, like a new transmission for instance, are a lot, lot more expensive.
Obviously car makers do whatever they can to incorporate previously developed parts, develop new parts and components with an eye on controlling costs, or farm the new part out to suppliers.
The development costs of parts adds to the cost of each vehicle. The more vehicles sold, the more development costs are spread out and around.
One of the many advantages of electric cars is fewer parts relative to conventional cars. Electric motors themselves are simple things with only one moving part: The rotor. Electric cars don't need transmissions, emission control systems, or complicated fuel, intake or exhaust systems. Because of their relative simplicity they should be less expensive to develop than conventional cars. Low development costs may be one reason car companies are interested in offering electric cars in their model lineups. Start up, electric-only car companies, certainly have smaller, less-costly-to-operate engineering, research and development operations than companies that sell conventional cars or even complicated hybrids for that matter.
Adding to the simplicity and ease of development, electric car makers can often use off-the-shelf, ready-to-go, commercially available parts and components to design and develop their vehicles. There's significant development savings when a needed part can be obtained just by making a phone call or purchasing over the Internet.
Automobile part and component suppliers have for a number of years been stepping up to the plate and, on their own, have been developing hybrid and electric vehicle components, before car builders even had a use for them. These suppliers have been betting on the notion of "build it and they will come." Knowing a component is available might encourage a car builder to go ahead with a project it hadn' t considered before. The car builder might begin a new project based solely on the availabilty of a new component.
One of those components for electric drive is brewing. It could draw many new players into the electric car business. It could also encourage existing electric car builders to develop new, hopefully less expensive models.
That component is an in-wheel electric drive motor under development by Protean Electric.
The company says this in its website:
Protean Electric has designed and developed a unique in-wheel electric drive system for hybrid, plug-in hybrid and battery electric light-duty vehicles. The Protean Drive (tm) system can improve vehicle fuel economy, add torque, increase power and enable improved vehicle handling to both new and existing vehicles.
Protean Drive (tm) is a fully-integrated, direct-drive solution that combines in-wheel motors with an integrated inverter, control electronics and software – no separate large, heavy and costly inverter is required. Each motor packages easily in the unused space behind a conventional 18- to 24-inch wheel and can use the original equipment wheel bearing. The direct-drive configuration reduces part count, complexity and cost, so there is no need to integrate traditional drivetrain components such as external gearing, transmissions, driveshafts, axles and differentials.
Direct-drive, in-wheel motors require no gearboxes, driveshafts or differentials thus giving far greater flexibility to vehicle designers while substantially reducing drivetrain losses. The reduced drivetrain losses mean less energy is wasted (during both acceleration and regenerative braking), resulting in more of the energy from the battery pack being available to propel the vehicle.
Each in-wheel motor can be controlled entirely independently, providing far greater control, performance and vehicle dynamics than any other drive system.
In addition, traction control, launch control and torque vectoring are all easily implemented through the use of in-wheel motors.
The company is developing its in-wheel drive package to make it easy to car and truck manufacturers to begin building more electric and hybrid vehicles. From an engineering standpoint a new electric vehicle might be developed by pulling out all the conventional, internal combustion related parts (engine, transmission, fuel system) then bolting on the new in-wheel motors and installing batteries wherever they fit.
Protean says more:
A key requirement that drove Protean’s motor design was the ability to be retrofit on existing vehicles. Designing any technology into a vehicle development cycle creates lead times of 3 to 5 years. But global OEMs need to significantly increase the fuel economy of and remove significant amounts of carbon emissions from their entire fleet right now. A handful of niche vehicles will not achieve these mandates. The ability to engineer a hybrid or full EV on an existing platform, with minimal tear-up of existing hardware or intrusion into passenger, storage or accident-vulnerable space cannot be underestimated and is one of the main advantages of choosing an in-wheel motor to propel a vehicle. It is therefore highly desirable for an in-wheel motor to be able to be fitted to a car without requiring any special wheel design or requiring risky suspension modifications, and this played a large part in the development of the requirements for the Protean motor.
Protean is no newcomer to the electric drive business. Its technical heritage goes back 30 years. The company was founded through the bankruptcy and split-in-two breakup of UK-based PML Flightlink that was specializing in specialising in the design and manufacture of "pancake" (flat) electric motors. The company operated in a number of markets including defense, aerospace, mobility, motion control, processing and printing.
The company is based in the Troy, Michigan with its engineering center in Farnham, England.
As an example of how common electrification of cars could come in the future, here in North America some AAMCO franchises will soon be offering hybrid conversions from XL Hybrids on select models of light trucks. Decades-old AAMCO currently specializes in repair and rebuilding of automatic transmissions for cars and trucks.
Who knows? Maybe in the near future they’ll be offering all-electric drive conversions or hybrid conversions that require little more than replacing wheels with in-wheel motors.
RETHINKING ELECTRIC CARS - PART 1
If EV’s don’t catch on at a quicker pace, manufacturers might have to go back to the drawing board.
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