Editor's note: In Part 1 of this two-part series, we look at the core technology and design choices behind this electric vehicle. In Part 2, we will discuss some mechanical and structural challenges, the specifications, road test results, and what will be next in improvements for this amazing EV effort.
Frustrated by fast-rising gasoline prices, John Santini, vice president of engineering at TDI Power, decided to turn his creativity and problem-solving skills toward developing his own electric vehicle.
Here's what a Pontiac Fiero "donor" car, Li-ion batteries, and a 18.7 kW electric motor can be put togetherto do, courtesy of our sister publication EDN.
I always wonder the same,
are we doing the exactly the same as to applied to
charging a car battery. Does GM (Volt)knows how a
Dynamo works..a dynamo will do the trick, without having to use an ICE to run a generator.
Internal combustion Engines are around 35% efficient, electric Motors around 90%..add about 15% for mechanical loss, drag..etc and the Efficiency of ICE powered vehicle is at most 25%. EV's are close to 75% efficient.
You can look at real world cost per mile. AAA quotes Total cost per mile of 41.4 cents for a small sedan.
Real world data for total cost per mile for pure EV's does not really exist, though cost projections are thought to be on the average of three times less then ICE..
So #4 is a yes. The braking system is sophisticated enough.
#2, #3: Are there any station offering recharge services? What is the cost per KW*Hr? Gas contains 36.6 kWh/US gal of energy. That's 10.9 cents per KW*Hr at $4 per gal. Most power companies here in TX are charging 11 cents per KW*Hr. No savings there. So I guess it comes down to efficiency. What is comparison of miles per gallon vs. miles per KW*Hr of the cars?
Personally I would expect the EV to be better around town with the regenerative braking. But not so on the highway. What do the tests show?
The brakes don't dump power back...the control system senses the need to slow down by monitoring the brake pedal and slows down the motor which effectively causes power to be directed back into the batteries. When the brake pedal is pushed past a point where regenerative braking is not enough, the hydraulic brakes kick in...Most all newer sychronous motor controls have this capability, no changes to the Brakes are required, except to the Brake pedal.
That's nice, but:
1. What direction is the cost of electric power going?
2. Where do you have to go to recharge?
3. How long does it take to recharge batteries vs. gas tank?
4. Are the brakes sophisticated enough to dump KE back into the batteries?
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