Charging ahead with electric motor cars
Throughout history it is evident that man has exercised his creativity best when he is put under pressure. The newest demand is to find a way to ween ourselves off of fossil fuels and their ecological hazzards. This is no small undertaking for many reasons but primarily because we have had several generations of oil dependency. It’s not easy to make such a massive change but we all know that it needs to start somewhere.
Thanks to a few imaginitive entrepeneurs we are starting to see some creative changes taking place. The electric car has been on drawing boards for quite some time and serious advances have been made of late. In an explanation of the electric car motor it needs to be understood in the framework of two types of electricity. A (DC) direct current motor can run on anywhere from 96 to 192 volts. Many of these have been used in the forklift industry for years. The (AC) alternating current motor usually runs at 240 volts and is used in conjunction with a 300 volt battery pack.
One of the advantages of the DC type controller is it’s overdrive factor. In other words, it has the ability to generate five times it’s normal horsepower for short periods of time which is valuable for quick acceleration. The downside of this though is the heat build-up on the motor. Too much overheating can eventually destroy the motor. AC type controllers have an advantage of what is called the ‘regen’ feature. The motor actually generates electricity during the braking process which is then returned to the battery.
With both of these options there are still some serious obstacles that have to be addressed. The average battery pack weighs more than 1,000 pounds. A fully charged battery is good for approximately 50 miles and charging the battery is time consuming (from 4 to 10 hours). Finally, a battery will last only three to four years and the replacement cost is around $2.000. As battery technology advances it will become more efficient.
One feature that will be carried over from today’s gas powered engine is the standard 12 volt lead-acid battery. This will still be used for powering all of the automobile accessories such as headlights, fans, radios, computers and the like. This means that, in the electric car there will be the need for a DC to DC converter. The converter will draw power from the main battery and convert it to 12 volts to recharge the accessory battery. When the car is driven the accessories will be powered by the converter and when it is idle they will draw from the 12 volt battery.