Capacitors Research Paper

A capacitor which used to be called a condenser, is a passive electrical component that is used to "store electricity" in the form of an electrical charge. There are many different kinds of capacitors available from very small capacitor beads used in resonance circuits to large power factor correction capacitors, but they all do the same thing, they store charge.

The simplest kind of capacitor has two parallel conductive plates separated by a good insulating material called the dielectric. Due to this insulating layer, DC current can not flow through the capacitor as it blocks it allowing instead a voltage to be present across the plates in the form of an electrical charge. These conductive plates can be either circular, rectangular or cylindrical in shape with the dielectric insulating layer being air, waxed paper, plastic or some form of a liquid gel as used in electrolytic capacitors.

There are two types of electrical charge, positive charge in the form of Protons and negative charge in the form of Electrons. When a voltage is placed across a capacitor the positive (+ve) charge quickly accumulates on one plate while a corresponding negative (-ve) charge accumulates on the other plate and for every particle of +ve charge that arrives at one plate a charge of the

This would result in the charge across the plates remaining constant indefinitely once the source voltage was removed. However, real capacitors have some leakage current which pass through the dielectric between the two plates. The amount of leakage current that a capacitor has depends upon the leakage resistance of the dielectric medium being used. Also an ideal capacitor does not lose any of the energy supplied by the source voltage as it is stored in the form of an electric field between the two plates but in real capacitors power is lost due to this leakage current and the resistance value of the