The research supported by this proposal will establish a scientific framework which gives insight into the design of nonlinear actuators. This will be accomplished through the expansion of nonlinear system theory and the proper formulation of nonlinear models for electromagnetic actuators, allowing for their deterministic optimal design. Additional contributions are expected in the fields of nonlinear system theory and electromechanical interactions. This work will develop the necessary expansions to nonlinear system theory so that a linearization and decoupling between performance measures and design parameters may be achieved for electromagnetic actuators. The design parameters could include the number of stator and rotor poles, the stator and rotor pole arcs, the active radius, the axial length, etc. The performance measures could include the average torque as a function of speed, the torque-ripple, inertia, etc. The running example to be used throughout this work is the design of the variable- reluctance motor. This motor has already has nonlinear control techniques applied to it, and it is a difficult motor to design because of its spatial and magnetic nonlinearities. The work proposed here is significantly different from applying linearizing control laws. In this project, the system theory would be exploited to yield a closed form optimal design. This is a natural extension of previous modeling work and will directly address important design issues. In addition, the incorporation of nonlinear system theory represents a departure from all documented design work and if successful, could completely reorient the way the design problem is viewed. Further, the design process would benefit from the discipline the system theory approach would impose on it.
