HVinsulation: SURGE ARRESTOR

Synopsis

This course provides an understanding of high voltage insulation in power systems networks. The first part of the course stresses on the phenomena of conduction and breakdown in insulation materials in order to provide the students with a firm knowledge on high voltage phenomena and insulation technology. The second part of the course covers the introduction to dielectric properties of materials, diagnostic testing of insulation and insulation coordination. The course also describes the design, performance, application and testing of outdoor insulators. By adapting this knowledge, students will be able to develop essential technical skills in solving real-world problems involving insulation characteristics with some degree of acceptable conditions. Besides that, the students will be able to identify business oppurtunity from this course through the specific assignment work that related to entrepreneurship skills.

Thursday, 5 May 2011

SURGE ARRESTOR

ARRESTOR

Demonstrate further the use of travelling wave theory.
The effect of arresters in limiting the surge voltage at locations remote from arrester.
Assume arrester is considered as an ideal or constant-voltage arrester.
The arrester maintains a constant voltage EA that is independent of the current being discharged by arrester.
The arrester appears as an open-circuit until this voltage is reached.
At that time, the arresters appears as a short circuit until this voltage is reached since the voltage is held constant.
Of course this is untrue but the assumption does produce some useful equations.

SURGE ARRESTOR PERFORMANCE

Surge voltage at remote location from arrester is a function of separation distance

Now consider the circuit of Fig above, which shows an arrester located in front of a transformer, which is here represented by an opened circuit and located behind a piece of equipment generically denoted by an opened circuit.

LATTICE DIAGRAM: ARRESTOR PROTECTION