Modeling and Analysis of Scalable Arcless Micromechanical Switches for Power Applications

Abstract

This thesis presents the modeling and analysis of scalable arcless micromechanical newlineswitches for power applications. The proposed switching system consists of Total Cross Tied (TCT) array of electrostatically actuated micromechanical switches, which operates under hot switching condition. A conceptual model of scalable Total Cross Tied (TCT) array configuration of micromechanical switches has been introduced to enhance higher rating. Performance of mechanical switch, solid-state switch and micromechanical switch array are compared for 400V, 6A DC system and 230V, 6A AC system using MATLAB Simulink and literature data. This provides the voltage, current and power characteristics of the micromechanical switch array. The comparative study shows that the proposed switch array gives better performance in terms of voltage drop, leakage current and power loss. This work identifies four parts of the micromechanical switch at which arc might occur. Driving electrode is one of the arc occurring part, which is supplied with DC voltage. It is a non-touching electrode. Breakdown arc occurs in this electrode, which is due to breakdown voltage and electric field. This work presents breakdown voltage and breakdown electric field based on modified Paschen curve for Al, Cu, Au and Pt materials for the gap between 0.5and#956;m and 30and#956;m. This curve provides the boundary between the arc and arcless region. This work proposes to design and analyze arcless driving electrode using mathematical modeling and Finite Element Modeling (FEM) simulations. The electric field distribution across the driving electrode during ON-state and OFF-state of the micromechanical switch are obtained. The influences of contact gap and contact size are also simulated. The arc occurrences for driving electrodes at various voltages are also simulated and results are presented. newlineFurther this work proposes to design arcless microelectrical contact based on newlineelectrothermal behavior using mathematical modeling and FEM simulations. The newlinemicroelectrical contact is a touching