Possible Applications of a Tapped Reactor Series Connected to a Transmission Line in the High Voltage Grid

This paper points out possible applications of a tapped reactor, which is series connected to a HV transmission line. The different taps of the reactor can be short-circuited by switching elements in order to achieve a stepwise adjustable impedance. Vacuum Circuit Breakers (VCBs) are used in this case as switching elements as they can be switched more often without maintenance compared to other circuit breakers. The switching frequency is rather strongly limited by the mechanical properties of the VCBs. Hence, the application range seems to be limited to slower processes for example the load displacement in a meshed grid. In order to extend the application range to faster events, this paper describes an approach where more VCBs are switched in parallel to each other. Hence a higher periodically switching ability could be achieved. A possible application therefore is the damping of power oscillations, which can occur due to disturbances in electrical power systems. The electrical stress on the VCBs and the tapped reactor is investigated in this study for every regarded case. The simulation is carried out with PSCAD.