Integral Solution of 3D Electric Field of a Disconnector

The disconnectors belong to elements widely used in electrical power engineering and apparatus technology for disconnecting various electric circuits. Usually they work without voltage (the circuit is first switched off by a circuit breaker). Nevertheless, in a fault regime the contacts of the disconnector may carry the full voltage, which may result in the electric arc between them at the moment when the movable contact approaches to the fixed one. In order to estimate this moment it is necessary to know the time evolution of the electric field in the domain between both contacts. This problem is solved in 3D (in somewhat simplified geometry) by the integral technique. The theoretical analysis is supplemented with an illustrative example whose results are discussed.