Controllability and small-signal oscillations of magnetic flux linkages in doubly fed induction machinesPolajžer, Boštjan (Avtor) Muetze, Annette (Avtor) Seyed-Bouzari, Seyed Ali (Avtor) Ritonja, Jožef (Avtor) contorollabilitydesign optimizationdoubly fied indusction generatorsmodal analysisThis paper examines the controllability of the stator and rotor magnetic flux linkages of doubly fed induction machines (DFIMs), considering small-signal oscillations and their relationship with electromagnetic machine design. To this aim, we first analyze 66 sets of lumped parameters from the dynamic model of a DFIM. Based on this, we classify DFIMs into three categories based on their modal parameters, namely, two for wind applications and one for pumped-hydro applications. Additionally, we identify reciprocal relationships between the damping of both identified oscillatory modes and the largest eigenvalues of the stator and rotor controllability Gramian matrices. Among the different lumped parameters, the winding resistances are found to influence these relationships the most. All analyzed DFIMs for wind applications were found to be less controllable and to exhibit better damping of oscillatory modes than DFIMs for pumped-hydro applications. Furthermore, based on the results of the controllability analysis, we selected three objective function candidates suitable for an optimization procedure aimed at minimizing the energy required to control the rotor flux linkages. An example objective function was evaluated in a multi-objective DFIM design process for wind applications that enables the design of more controllable machines that provide the desired damping of oscillations, which can consequently contribute to improving grid resilience.IEEE XPLORE20252026-01-14 14:04:31Članek v reviji96496UDK: 621.313COBISS_ID: 263434499DOI: 10.1109/TEC.2025.3647982ISSN pri članku: 1558-0059sl