Matlab language as tool for symbolic, semi-symbolic and numerical simulation of electrical networks

Abstract

The paper deals with the application of MATLAB mathematical language [2] for simulation of electrical and electronic networks. A library of about 40 m-files (scripts and functions) is described that solves the following problem: automatic formulation of network equations in matrix form (both symbolic and numerical); evaluation of numerator and denominator polynomials for network functions; calculation of polynomial coefficients, zeros and poles; calculation and plotting of frequency-domain characteristics and sensitivities to variation of parameters of network elements; calculation and plotting of time-domain responses to unit impulse and step functions, to arbitrary input signals and periodic components of responses to periodic input signals. Virtually all the problems can be solved in various ways and the user has the possibility to choose individual solution procedures and to compare them from the point of view of accuracy, speed of solution and reliability of the results. The m-functions utilize the MATLAB built-in functions to realize most mathematical operations. To satisfy some needs, however, special functions are written. All m-functions are written in readable form and can be easily modified by the user if necessary. The prepared functions are used to support teaching simulation methods at both undergraduate and graduate level of study.