Charging system PT 1
http://www.youtube.com/watch?v=oYTrbD
LSy_w
Purpose
Purpose of charging system to keep battery
at a fully charged state.
Provide power for all electrical loads
Alternator is the component that
generates electricity to charge the battery.
Principle
The principle of electromagnetic induction
to generate electrical energy from
mechanical energy
Electromagnetic induction involves the
generation of an electrical current in a
conductor when the conductor is moved
through a magnetic field.
How do we increase electricity
Demonstration with alternator on how electricity
is generated.
How can we increase electricity
Increasing Current
Increasing the speed of the conductor
through the magnetic field.
Increasing the number of conductors
passing through the magnetic field
Increasing the strength of the magnetic
field.
AC and DC
AC– Alternating current
DC– Direct Current
Alternator generates AC voltage.
Automotive battery and vehicle system
using DC voltage.
AC and DC
So what changes the AC to DC voltage.
The voltage Rectifier.
Rectifiers are consisted with six diodes.
Diodes are one way check valves that only allow
current to flow one way .
AC to DC
What is the proper system voltage?
13.8 - 15 volts
27.4 – 28.4 volts
What controls the system voltage?
Voltage regulator
Voltage Regulator
- Controls the voltage output of the
alternator.
- The regulator receives system
voltage as an input, in order to
regulate alternator output voltage.
Voltage Regulator
End
http://www.youtube.com/watch?v=Yv4t795Yb
5k&feature=related
What can cause the charging system to
under-charge?
Loose fan belt
Low engine RPM
Excessive load requirements
(add on accessories)
What can cause the charging system to
under-charge?
Short driving trips
Defective generator
Defective voltage regulator
Defective wiring
Rotor, creates spinning magnetic field
Stator, creates alternating current
Slip Rings, allow field current into the rotor
Brushes, allow field current into rotor
Voltage Trace for Three Stator Windings
Full Wave Rectification …
... three stator windings
Actual voltage trace of each stator
winding after full wave rectification
voltage trace on oscilloscope
(diode pattern)
Stator
Rectifier (Diode
pack)
How does the voltage regulator control
the A/C generator?
The regulator will turn on/off current
to the field windings (rotor)
Increasing current to the rotor…
…will increase generator output
14 V
80 o F
1V
http://www.youtube.com/watch?v=Bzz7P3qNHcE