Applications of Power Transformers: Transformers are the first to encounter lightning and other high voltage surges. The transformer insulation has to withstand very high impulse voltages many times the power frequency operating voltages. The Applications…
Insulating Materials Types: There is no piece of electrical equipment that does not depend on electrical insulation in one form or an other to maintain the flow of electric current in desired paths or circuits.…
High Temperature High Performance Polymers: High Performance Polymers films are thermoplastic and are generally transparent. The are needed for use in applications where temperatures vary from very low (- 269°C) to very high (+ 400°C)…
Solid Dielectrics Used in Practice: The majority of the insulating systems used in practice are solids. They can be broadly classified into three groups: organic materials, inorganic materials and synthetic polymers. Some of Solid Dielectrics…
Breakdown in Composite Dielectrics: It is difficult to imagine a complete insulation system in an electrical equipment which does not consist of more than one type of insulation. If an insulation system as a whole…
Breakdown of Solid Dielectrics in Practice: There are certain types of breakdown which do not come under either intrinsic breakdown or thermal breakdown, but actually occur after prolonged operation. These are, for example, breakdown due…
Electromechanical Breakdown and Thermal Breakdown: Electromechanical Breakdown:When solid dielectrics are subjected to high electric fields, failure occurs due to electrostatic compressive forces which can exceed the mechanical compressive strength. If the thickness of the specimen…
Intrinsic Breakdown: When voltages are applied only for short durations of the order of 10-8 s the dielectric strength of a solid dielectric increases very rapidly to an upper limit called the intrinsic electric strength.…
Solid Dielectric Materials: Solid dielectric materials are used in all kinds of electrical apparatus and devices to insulate one'current carrying part from another when they operate at different voltages, A good dielectric should have low…
Conduction and Breakdown in Commercial Liquids: As already mentioned, Conduction and Breakdown in Commercial Liquids are not chemically pure and have impurities like gas bubbles, suspended particles, etc. These impurities reduce the breakdown strength of…
