http://www.youtube.com/watch?v=oYTrbDLSy_w

Charging system PT 1

Charging System

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.

Purpose

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.

Principle

Demonstration with alternator on how electricity is generated.

How can we increase electricity

How do we increase electricity

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.

Increasing Current

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 and DC

AC to DC

13.8 - 15 volts

27.4 – 28.4 volts

What is the proper system voltage?

Voltage regulator

What controls the system voltage?

- Controls the voltage output of the alternator.

- The regulator receives system voltage as an input, in order to regulate alternator output voltage.

Voltage Regulator

Voltage Regulator

End

http://www.youtube.com/watch?v=Yv4t795Yb5k&feature=related

Charging System PT2

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

What can cause the charging system to under-charge?

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)

The regulator will turn on/off current to the field windings (rotor) Increasing current to the rotor… …will increase generator output

How does the voltage regulator control the A/C generator?

1 V

14 V

80 o F

http://www.youtube.com/watch?v=Bzz7P3qNHcE