Optimization of Mechanical States in Wound Capacitors

Abstract

The winding process is encountered frequently in manufacturing, such as winding of polymer films and paper, laminated pressure vessel construction, and the manufacture of wound capacitors. The winding of capacitors will typically involve hundreds of plies of conductor and dielectric wound over a core. Due to the large number of layers, the calculation of the mechanical states within a wound capacitor is a significant computational task. Techniques for calculation of the mechanical states within a wound capacitor are derived and discussed in reference [1]. The focus of this paper is the formulation and application of optimization techniques for the design of wound capacitors. The design criteria to be achieved is a specified uniform wound tension in a capacitor. The paper will formulate an optimization statement of the wound capacitor design problem, develop a technique for reducing the numerical calculation required to repeatedly analyze the capacitor which is required by the optimization algorithm, and apply the technique to an example. The following effects will be investigated using the example. (1) The ability of low order winding tension profiles, such as constant, linear, or bilinear profiles, to meet the optimization objective. (2) The usefulness and practicality of high order winding tension profiles, which require a significant number of design variables to meet the optimization objective. (3) Differential weighting of the aluminum and mylar layer wound tensions in the objective function will be investigated as a technique for achieving the optimization/design goal.