Blue Bird TC/2000, Руководство пользователя

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ELECTRIC VEHICLE INFORMATION
INTRODUCTION
Blue Bird Corporation and Northrop Grumman Electronic Systems have developed the first purpose
built all-electric school bus. This is a full size 72 passenger vehicle based on the popular TC/2000 chassis
design. This portion of this manual is designed to assist the operator and maintenance personnel with their
familiarization and operation of the valve regulated lead acid powered electric vehicle. It contains informa-
tion peculiar to the Blue Bird electric school bus. Any procedures discussed herein for driving, charging, etc.
shall not be applied to any vehicle other than those valve regulated lead acid powered vehicles.
WARNING: The electrolyte in the vehicle batteries is an absorbed electrolyte glass mat, consisting of
sulfuric acid. Sulfuric acid can cause severe burns. There is no means of gaining access to the inside of the
battery. There is no liquid electrolyte and exposure can occur only if a battery is cut open and the internal
cells are exposed. If you happen to get any electrolyte on your skin or in your eyes, flush the affected areas
with large quantities of water for at least 15 minutes, and seek medical attention.
WARNING: The voltage of the battery packs is approximately 336 volts DC. Do not attempt to service the
vehicle yourself. Initial service training will be provided and a separate service addendum will be pro-
vided. Failure to follow proper procedures can result in serious injury or death by electrocution.
WARNING: The batteries may produce potentially flammable and explosive gasses during charging that
could accumulate to dangerous levels in non ventilated areas. Do not charge the vehicle in an enclosed
area. Keep flames and sparks away from batteries. Just as you would do during “fueling” your personal
vehicle, do not smoke when “fueling” (i.e. charging) the electric vehicle.
WARNING: Seat belt use is mandatory for the operator during vehicle operation.
FUNCTIONAL DESCRIPTION
The electric vehicle is different from any other vehicle you have ever driven. When driving this vehicle,
you will notice the absence of noise typical of an internal combustion engine, whether it is gasoline, diesel or
natural gas powered. There will also be an absence of the distinct shifting of gears that you can feel when
driving a combustion engine vehicle equipped with an automatic transmission.
The traditional internal combustion engine parts are gone. There is no water-cooled, piston-driven en-
gine. There is no clutch or transmission that shifts gears. There is a speed reducer which slows the motor
speed so it can drive the rear axle. Whenever the bus is moving, the motor is always in “gear”. It runs at
approximately 12,500 RPMs at a maximum bus speed of 55 MPH. The motor turns backwards in order to
drive the bus in reverse. It does not “hurt” the motor to apply full torque at zero RPM or to “stall” the motor.
There is no exhaust system that release combustion by-products into the atmosphere. There is a receptacle,
for battery charging, near the right rear side panel. There are one hundred and twelve (112) valve regulated
lead acid batteries mounted underneath the vehicle in the luggage compartment areas in four separate packs
of twenty-eight (28) batteries each. These battery packs are called Traction Battery Packs. There are special
radial “Ultra Low-Rolling Resistance” tires.
The principle elements of the electric vehicle propulsion system are the chassis controller, the battery
pack, the motor controller, the power distribution unit, the motor and speed reducer which are schematically
depicted in the following diagram. The following is an overview of the propulsion system operation when
the vehicle is being driven.
The Chassis Controller is a microprocessor controlled device that senses the accelerator and/or brake
pedal position, and converts this information into torque commands for the Motor Controller. The Motor
Controller examines the torque requirement information and other operating conditions such as present motor
speed and direction and implements a proprietary Vector Control Algorithm. This Vector Control Algorithm