STABILITY STUDY OF CLOSED NONLINEAR SYSTEM “FREQUENCY CONVERTER - ASYNCHRONOUS MOTOR” USING MATLAB

The article provides a block diagram of a closed non-linear system “frequency converter - asyn chronous motor” in the MATLAB environment with a description of the transfer functions of the system. A mathematical description of transient processes of a closed system with a nonlinear link in feedback is given, a program for solving a system of differential equations describing the dynamics of transients of a closed system is given. Comparisons of transients of a linearized system with transients of a nonlinear closed-loop “frequency converter - asynchronous motor” system are given. The algorithms for determining the stability of a nonlinear system using the phase trajectory method, the harmonic linearization method, and the method of solving nonlinear equations in symbolic form have been broken. For each method, system stability determination programs are given. The source data for the open-loop system “frequency converter - asynchronous motor” is the same, for a non-linear feedback system different. The results of the stability study of a closed system “frequency converter - asynchronous motor”, the study of the transient characteristics of the system using the software environment MATLAB are given.

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