Controlled Switching of Non-coupled & Coupled Reactor for Re-ignition free De-energization Operation

This paper describes the controlled switching strategy to minimize probability of re-ignition during the de-energization operation of a shunt reactor considering electric and/or magnetic coupling. The effect of coupling in terms of the shortening and elongation of last half cycle loop of current and transient recovery voltage appearing across the contact gap after current interruption have been discussed. Furthermore, the procedure to derive needed arcing times for individual phases to reduce probability of re-ignitions has been discussed for various reactor configurations. Also, simulation is performed for various reactor configurations in ATP-Draw software with results validated by performing testing on scaled down model test bench.