System Design of Fast Actuator for Vacuum Interrupter in DC Applications

Abstract

One of the major challenges of DC circuit breakers is the required fast mechanical actuator. In this paper, a Thomson coil actuator system for a vacuum interrupter is designed. Active damping is used to decelerate the moving contacts. Challenges are discussed, especially concerning the power supply needed for the Thomson coil actuator. The design philosophy is explained and FEM simulation results are presented. The results indicate that a wide range of combinations of drive circuit capacitance and voltage fulfill the requirements for armature acceleration. However, active damping requires a very careful selection of drive circuit voltage and timing of applied damping.

Enhanced Active Resonant DC Circuit Breakers Based on Discharge Closing Switches

“…The opening and closing time of the VI will be 3.5 ms and 4 ms, respectively. The values deviate from the ones reported in [38] due to minor design changes. To interrupt, current injection is started after an interruption delay of 2 ms which can be shorter than the The results from an interruption capability test are shown in Fig.…”

“…This interface enables communicating with the control system of the DCCB. The relevant parameters have been extracted from simulations of a prototype VI actuator system [38]. The opening and closing time of the VI will be 3.5 ms and 4 ms, respectively.…”

Thomson-Coil Actuator System for Enhanced Active Resonant DC Circuit Breakers

“…The authors showed that the second excitation is inefficient because the increasing contact gap reduces the electromagnetic coupling of the excited TC and the armature. Active damping of the TCA used in this work was already studied with finite element simulations for DCCB application [15]. The authors concluded that the requirements on the TCA system, specifically the DC power supply, are stringent and that active damping works only for a narrow parameter range.…”

“…The eddy currents induced in the armature cause a repelling magnetic field that, in this case, decelerates the armature. Active damping has to be perfectly timed for proper deceleration as studied in [15]. Otherwise, the armature may hit the opposing TC with high impact and damage it.…”