Optimal Design of Contact Configuration for High Voltage Vacuum Interrupter Based on Response Surface Method and Multi Objective Genetic Algorithm

Magnetic field generated by the contacts of Vacuum Interrupter (VI) support the interruption of fault current. Therefore, the interruption performance of VI is mainly influenced by the contact configuration. To develop high voltage VI, it is important to design and optimize the contact configuration applicable in high voltage system. Various contact configurations have been suggested for high voltage VI in the literature, whereas the optimization technique of suggested designs has not been performed yet. Therefore, in this paper, the optimization technique of the contact configuration for high voltage VI was proposed based on response surface method (RSM) and multi objective genetic algorithm (MOGA). The four design factors and three objectives were considered for optimization. The four design factors are coil height (h), coil width (w), slit length (l) and mounted angle (a). The three objectives are maximum axial magnetic flux density at peak current (B
z
), effective area ($\lambda$), and maximum axial magnetic flux density at current zero (B$_{zo}$). The optimization was performed by applying MOGA to the regression equation of the objectives derived by RSM with Central Composite Design (CCD). As a result of optimization, B
z
and effective area increased by 6% and 9%, while B$_{zo}$ decreased by 10%. Consequently, it was confirmed that the interruption performance of high voltage VI could be improved by optimization.