This paper considers the stability of dynamical systems described by differential equations with fractional derivatives. In contrast to a number of works, where the differential equation describing the system may have a set of different values of fractional derivatives, and the characteristic polynomial is formed on the basis of the least common multiple for the denominators of these indicators, this article proposes forming such a polynomial in a specific

*j¹/³*basis and studying the stability of systems with such fractional description based on the resulting rotation angles of

*H*(

_{n}*j*ω) vector at a frequency change from zero to infinity.

^{l/m}This technique is similar to the investigation of system stability by frequency criteria used for a similar problem in describing the system by differential equations in integer derivatives.

The application of characteristic polynomials formed in the *j¹/³ *basis for the description of the processes in dynamic systems and the analysis of the stability of such systems on the basis of the frequency criterion are the essence of the scientific novelty of this paper.

The article contains the following sections: problem statement, work purpose, presentation of the research material, conclusions, list of references.

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