EV PRESENTATION OUTLINE
(Slide 1) Hi. My name is ( your name), and I'd like to talk to you today about electric vehicle technology.
(Slide 2) First, some definition. EV stands for Electric Vehicle. Let's take a look at what's out there now. First, EV's are all over the place. Airport service vehicles, golf carts, and forklifts comprise a vast population of off-road EV's. These have been around for many years, and the technology is fairly well developed. But what about on the road? Are there roadgoing EV's today? - Yes. Not only that, but there is technology available to the general public that will allow you and me to build and operate a practical, fun-to-drive EV today. Let's look at some of the on-road EV's that are out there.
(Slide 3) OEM EV's. GM EV1
(Slide 4) Solectria Force
(Slide 5) Corbin Sparrow (That'll get attention). Also available is the Ford Electric Ranger.
(Slide 6) Hobbyist EV's. The hobbyist is unwilling to wait for an industry that never seems to move. There are 1000's of vehicles, although this is still a drop in the bucket for the USA. Most are conversions of ICE powered cars, so you'd probably never know.
So what does it take to build one of these conversions (besides batteries)?
(Slide 9) System components. Basically, it takes takes a motor, a motor controller, a battery charger, a DC/DC converter, a heater, Instrumentation, contactor(s), and electrical safety devices. We'll look a little at each of these.
(Slide 10) Motors. The motors you'll hear about have a deceptively low HP rating. This is because motor's ratings are for continuous HP, and produce many times that for short time periods. ICE engines can only produce their rated power at specific throttle, fuel flow, temperature, RPM, etc. "Test Bench" conditions. And then only for a short time. The performance characteristics of the electric motor better match real-world driving conditions.
(Slide 11) Most hobbyists use brushed DC motors
(Slide 12) here is a cutaway of the most popular motor for bobbyist conversions, the Advanced DC 9" motor.
(Slide 13) Controllers In general, the more volts you have, the higher top speed you have, and the more amps the controller can push through the motor, the more torque the motor will generate.
(Slide 14) This is what an Auburn controller looks like.
(Slide 15) Chargers - OEM uses weird hookups like GM's inductive paddle charger and the AVCON connector. The hobbyist wants to just use what everybody already has - a 120 or 240 VAC plug-in.
(Slide 16) DC-DC Converters - For safety reasons, you want to keep your car's 12V system totally isolated from the high voltage components. So how do you keep your 12V battery recharged? The solution is a DC/DC converter.
(Slide 17) Heaters - Just like in the little ceramic heaters you can buy at the hardware store. Resistive loads don't care whether the source is AC or DC.
(Slide 18) Here is what a typical core and frame look like.
(Slide 19) Instrumentation
(Slide 20) Contactors - BIG relays
(Slide 21) Safety
(Slide 22) Performance - Acceleration and speed for conversions is about the same as gas vehicles. Depending on the design, it ranges from "economy to muscle car". The DC motors are great for drag racing. The current electric drag racing record is 8.801 seconds in the 1/4 mile by "Current Eleiminator".
(Slide 23) This purpose built vehicle, the tZero, is probably the fastest street-legal EV available.
(Slide 24) Range - Somewhat dependent on speed and whether you have a lead foot, but typically 30-60 miles. Over 100 miles easily achievable with a purposeful design or with advanced (non-lead-acid) batteries that are not available to the public yet. This is a great match for today's driving habits. Example - commuting. Use an ICE car for long trips.
(Slide 25) This EV pickup gets over 120 miles range
(Slide 26) With plain old flooded lead-acid golf cart batteries!
(Slide 27) Emissions - Common claim is that pollution is only moved. Point taken, but overall efficiency jump plus scrubbing of power plant emissions reduces overall emissions significantly.
(Slide 29) - This is just an overview of the components available and what has been done with them. These are available, just not widely known.
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