Design of a fast linear drive for (hybrid) circuit breakers - Development and validation of a multi domain simulation environment

The force acting on a current carrying body, which is induced by magnetic fields gained more interest due to new applications. These magnetic techniques are used for decades to accelerate or move objects, for instance for catheter navigation in the human body, metal forming or for fast opening of electrical circuit breakers. Due to the increase in short circuit power in most grid systems, and thereby larger prospective currents, conventional AC and DC switches lose interest. This has led to an increased interest in faster and hybrid switching techniques. For this reason a novel electro-mechanical set-up has been developed, which accelerates a movable electrical contact extremely fast by using the combination of Lenz law and the Lorentz force. This contribution describes the mixed domain simulation environment and the validation of the set-up, which consist of a linear electro-magnetic drive and a mechanical damper system. The prototype used for validation is capable to generate a maximum driving force of approximately 200 kN, which accelerates the movable contact of 2.7 kg to 18 m s¿1. Initial simulations have been compared with the measurements and the results are in good agreement. This tool can be used to develop generic hybrid circuit breakers, reduces the risk for switchgear manufacturers and speed up the introduction of hybrid switch systems, which is urgently needed due to the ever increase of short circuit power in grid systems and the introduction of DC grid systems.