Convergence Analysis of the Distributed Analytical Representation and Iterative Technique (DARIT-Field) for the Field Coupling to Multiconductor Transmission Lines

This paper investigates the convergence and error evaluation of the distributed analytical representation and iterative technique (DARIT-field) which is a new approach for the analysis of field coupling to multiconductor transmission lines. The DARIT-field method has the advantage of high computational efficiency over the other methods. In order to know the convergence speed and the error at each iteration step of DARIT-field, an analytic expression of iterative error is derived by combining the two telegrapher´s equations into a matrix equation and using the euclidean norm to explore its upper bound. The expression shows that the convergence speed is mainly influenced by three parameters, namely coupling factor (CF), terminal loads, and the line length to excitation field wavelength ratio (d/λ). The convergence speed is a function of CF, terminal loads, and the line length to excitation field wavelength ratio (d/λ). These results allow the users to make a compromise between computational cost and accuracy by selecting the number of iterations.