Started in 2001
What is it and what can it do?
The Lorax is a vehicle that was donated to us by John Murphy in 2001. It runs solely on electricity. It can reach speeds up to 50 mph and has 34 electric horsepower with 75 foot pounds at the motor and 900 pounds at the drive wheels (front wheels) of torque. The car can travel 75 miles per charge and runs at 6 miles per kilowatt-hour (kWh).
Why are there 3 wheels?
With three wheels instead of four, there is less friction (making the car more energy-efficient) and the car is lighter (because of the removal of one wheel and axle).
What does the solar cell on the car roof do?
The solar cell on the roof holds a 12-volt battery which powers the Solectria Controller. It has no effect on charging the 12 – acid Deka batteries
Body of the Car
British kit car based on the 1930’s 3 – wheeled Morgan (Lomax kit car).
Frame: Citroen Deux Chevaux ( which means Two Horses in French)
What type of brakes does it have?
Inboard disc brakes in front and a single drum in the rear.
Regenerative Braking: When slowing down, the motor acts as a generator and the controller takes electricity from the motor and uses it to recharge the batteries (5-7% of the energy is returned).
What about the batteries?
PbA (Lead-acid battery) H2S04 – Sulfuric Acid
They are deep cycle batteries. They can hold a larger charge for a longer period of time than standard batteries.
GEL Battery – fluid (or acid) has been turned into slush. (A semi – solid). Doesn’t spill.
Gel Electrolyte – The substance through which the electrical current moves from one terminal to the other inside the battery.
They are a lead Acid Gel Battery – 12 volts DC(fully charged 13.6 volts) Useful Range(average between 13.6 and 10.5 volts, 10.5 when completely discharged).
Capacity of Batteries: 79 Amp Hours at the 3 hour rate (100 miles driving would use around 70 amp/hr)
12 batteries (made by Deka) X 69 lbs each = 828 lbs
828 battery weight + car weights 1232 = 2060 lbs total weight of car
Fully floored, 200 amps going into the motor
200 amps(fully floored)
X 144 volts (battery pack )
(1 HP (horsepower) in electrical terms is 750 Watts)
28,800 Watts/ 750 Watts = 34 HP
When charging the batteries, it is recommended that they are hit with 14.5 volts/battery then float the charge back down to 13.8 volts for charging. The 14.5 volt charge will break up the sulfation that accumulates on the plates. The batteries will last longer and perform better if the sulfation is burnt off.
When charging, these batteries respond best to an inrush current of 30 Amps or more. The charger uses AC current and converts it into 240 volts of DC current.
How does the motor work?
The motor is a 3-phase (3 – wires) AC induction (current is induced) motor. The electromagnetic field inside the motor is going around in a circle and the armature is moving around following the electromagnetic field making the motor move.
The armature is the only moving part inside the motor except for the bearings(the two bearing that hold the armature in place).
What does the controller do?
The controller takes the 144 DC from the batteries and converts it to a 3-phase AC current for the motor.
The 3- phase AC induction uses 3 different phases as pulses. The strength of the magnetic field moves the motor.
The controller takes input and translates them to directions for the motor.
Controller has circuitry in it called soft start which keeps the wheels from spinning. It keeps the acceleration down in in the car which keeps the front wheels under control