Air insulated vacuum generator circuit-breaker, incorporating three interrupters in parallel per pole, more than 100 kA system source short-circuit breaking current
Testing of generator circuit-breakers at this rating need to be carried out by the synthetic test method. This implies that a realistic arc duration needs to be guaranteed by artificially prolonging the arc duration by forced re-ignition. Because of the excellent high-frequency quenching interruption capability of vacuum interrupters, standard arc prolongation technology cannot be applied.
Therefore in such tests, ultra-high frequency current injection is needed to demonstrate the correct arc duration. KEMA Laboratories realized this through novel “super re-igniters”, developed in cooperation with Darmstadt Technical University, Germany. This new technology is based on a cascade of triggered vacuum- and air gaps, supplying a very fast high-current pulse.
Having verified this technology, more opportunities arise to test high-voltage vacuum circuit breakers in a synthetic method.
The photo shows the test set-up in KEMA High-Power Laboratory, with the breaker under test (and a series connected auxiliary breaker) in the foreground, and two super re-igniter units behind it.