Brief of High Voltage DC generation "Electrostatic generators method " such as Van de graaf generator and wimshurst machine

1. Electrostatic
Generators
By : Shady Ahmed Abd al-ghaffar Sec(5)
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2. Electrostatic Generator: is a device that produce static
electricity at high Voltage and low Current.
This static Electricity is generated by Friction or
Induction.
It is used to demonstrate electrical forces and high
voltage phenomena.
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3. Examples:-
Van de graaff generator.
Wimshurst machine.
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4.  Van de graaff generator
Principle of Generator:
Generally generators works on the principle of
faraday’s law. but, our Van De Graaff
Generator works on the static electricity
concept.
This generator
doesn’t have
field winding and conductor.
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5. Construction of The Generator:
Major parts of Generator are:
 Motor
 Two rollers
 A belt
 Two brushes
 An output terminal
(usually a aluminum sphere).
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6. Working of Generator:
 A small motor causes the rollers
To spin.
 The Rubber belt becomes positively
Charged at the bottom and moves
upward.
 When the positively charged belt
Reaches the top it gains electrons
And make the metal sphere positive.
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7. Working of Generator:
 The belt goes back down to
The bottom and loses its electrons
To become positive again.
 The potential difference achieved in
modern Van de Graaff generators can
reach 5MV.
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8. Applications
It is used to generate x-rays, which is
widely used in medicine field.
It is used in atom smasher’s, which is used
in research purposes.
It found applications in physics, medicine,
and astro physics.
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9.  Wimshurst machine
 Electrical device that can produces
a high Voltage by building up charge
of static electricity.
 It causes very good results
to power X-ray tubes.
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10. Construction10

11. 11  As one or both of the wheels spin, static
electricity is generated.
 The charge collectors
conduct this Charge
into the insulators
where it is stored.

12. 12  One Layden jar will become negativly charged and
the other will become positively charged.

13. 13  Eventually the insulators will have stored
enough charge to Send spark across the metal
balls.

14. Thank you.
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