Multibody analysis of dynamic characteristics in vacuum circuit breakers

Vacuum Circuit Breakers (VCBs) are important safety devices in secondary distribution networks to interrupt current in case of fault in the network or operation demand. To fulfill such duty, robustness of the kinematic chain is the key factor to secure reliability of the switchgear. There are strict requirements related to the motion of contacts in the vacuum interrupters (VIs) for both closing and opening switching operations. The kinematic chain must produce proper speed and specific stroke tolerances with controlled contact motion. This article presents the simulation method applied to optimize the kinematic chain of VCBs in higher pressure applications. A comprehensive view of involved parts in the kinematic chain is also presented, focusing on optimizing the stroke specifications of VIs (travel-characteristics) for reliable switching operations. Particular attention is given to energy efficiency, specifically regarding energy release and dissipation during switching operations, which are crucial for motion control and durability. A selection of techniques is presented with references to both multibody dynamic simulations (MBD) and experiments to demonstrate how to secure the performance of the VCB for a minimum of 10,000 switching cycles.