Comparison of the Methods for Electromagnetic Force Computation by Edge Elements

摘要

Three methods for electromagnetic force computation using edge elements are analyzed - the virtual work method, the Maxwell stress tensor method and the nodal force method. The methods are applied to compute the force at different air gaps of a voltage-fed nonlinear ac contactor. A comparison is made from the viewpoint of accuracy, speed and computer implementation. The sensitivity of the Maxwell stress tensor method to the choice of the integration surface is investigated. The computed results are compared with measurements.