Behavioral Analysis of Nonlinear Dynamic Operation Mode in Three-Phase Electrical Converters by the Bifurcation Method

Abstract

The operation of an electricity converter may be complicated by beyond-design dynamic modes with large voltage surges so that the converter breaks down. In modern procedures of designing electricity converters the nonlinear behavior of key elements and control systems of such converters is often left unconsidered. Beyond-design operation modes can be studied by parametric synthesis which involves selecting a defined set of parameters to maintain design mode and then using bifurcation analysis to define its boundaries and the possibility of nonlinear phenomena in the operation of the converter. Mathematical models of converters were developed and the boundaries of their design modes and bifurcation transitions studied. It is found out that in terms of nonlinear dynamics the Cuk converter has an acceptable calculated mode area and the minimal amplitude of oscillations in the region of undesired modes. The proposed algorithm of controlling nonlinear dynamics of converters allows eliminating nonlinear phenomena and expanding the calculated work area of the converter. The conducted nonlinear dynamics analysis is interesting to nonlinear dynamics researchers and scientists who survey the field of electrical converters.