High Temperature High Performance Polymers

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) values. Such applications include space shuttle solar arrays, high speed locomotive and other motor armature slot liners, capacitors, transformers, miniaturized […]

Solid Dielectrics Used in Practice

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 Used in Practice materials are listed in Table 4.2 below. Paper and Boards The kind of paper normally employed for […]

Electromechanical Breakdown

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 is d0 and is compressed to a thickness d under an applied voltage V, then the electrically developed compressive stress is […]

Intrinsic Breakdown

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. Experimentally, this highest dielectric strength can be obtained only under the best experimental conditions when all extraneous influences have been […]