Research On Permanent Magnetic Actuator For Vacuum Circuit-Breaker

Vacuum Circuit-Breaker used in railway are the core components of substation, section post and sub-switching post. With the fast growing of high-speed railways, Vacuum Circuit-Breaker is in great demand also. From early days it has been a research focus in many nations, related products are presented now and then. In the last few years, Permanent Magnetic Vacuum Circuit-Breaker is more widly applied because of its superior performance than the Spring ones. Some domestic research institutes and enterprises successfully released this new apparatus to meet the ever-rising need of Breaker.A Circuit-Breaker mainly consists of Vacuum interrupter, Actuator and Control Unit. Of which Actuator is so important that not only should it ensure the long-term action reliability of the Breaker, but also meet the requirements of Vacuum interrupter and Control Unit. Under this circumstances, here a way of how to design the Permanent Magnetic Actuator for a certain Vacuum interrupter is proposed.First the structure and basic principle of a Permanent Magnetic Actuator are specified, by comparing the Monostable with Bistable, it comes to conclusion that the latter one is more suitable in railway usage. Since parameters of a Breaker are primarily provided by its Vacuum interrupter and Permanent Magnetic Actuator, so before designing a rational Actuator, some certain kind of interrupter must be selected ahead. In this thesis, researching process for mechanisms such as the dynamic core, permanent magnet, coils, yokes and the covers is basing on this.Ansoft12is a commercial Finite Element Analysis software, and it has been widely used in various electromagnetic fields. First the two-dimentional model of the Actuator studied above is created. By defining its material properties, boundary conditions and applying auto-meshing, the model is then calculated under Finite Element condition. In the post-processing, its two-dimensional static magnetic performance is analysied. The Actuator’s three-dimensional model is established in Chapter5. Compared with the two-dimensional, it is available of making model simulation more accurate.