Structural Controllability of Electromechanical Networks.

This paper discusses structural controllability for non-strongly connected networks, especially an electromechanical network connected by an energy conversion de- vice. The energy conversion device is non- linear and all other associated devices are linear. Thus, this paper considers the linearized state equation for studying the structural controllability in the neighborhood of an equilibrium point. Because of the nonlinearity of the energy conversion device, the coefficient matrix of the equation is decomposed into the product of matrices for graph incidence information and resistances and the matrix for element values other than resistances. The sufficient condition for the structural control- lability is characterized by using only the first of these matrices. It is shown that the sufficient condition for the structural controllability of the electromechanical network is that its equivalent electrical network graph have no capacitor-only cut- sets and no inductor-only loops. [ABSTRACT FROM AUTHOR]