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A design for a passive magnetic bearing system that can stably levitate a rotor in all directions is described. The bearing system consists of levitation magnets coupled with a Halbach array stabilizer, which induces currents in stabilization coils, in order to overcome the inherent instability of a system composed only of permanent magnets. The levitation magnet system consists of two pairs of annular ring magnets which provide an upward magnetic levitation force to counteract the downward gravitational force of the rotor. The Halbach array stabilizer consists of two stabilization coils shifted in angular position with respect to one another and centered in the vertical direction between two rotating Halbach arrays. Magnetic fields from permanent magnets are calculated using superposition of fields due to patches of magnetization charge at surfaces where the magnetization is discontinuous. Induced currents in the stabilization coils are calculated by computing the time derivative of the magnetic flux through those coils. Magnetic forces on the rotor are computed using a superposition of forces on each patch of magnetization charge. The entire magnetic bearing system, consisting of both the levitation magnets and the Halbach array stabilizer, is stable to both vertical and lateral displacements. Results are compared with a simpler straightened approximation of the Halbach array stabilizer.

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This paper describes how to utilize physics-based unified modeling of complex electric power systems in order to design a multi-layered interactive Smart Grid in a Room Simulator (SGRS). In this simulator, the dynamic response of a given interconnected grid is simulated and assessed as a family of interfaced sub-processes jointly evolving at different timescales. Compared to state-of-the-art simulators, advantages of the SGRS are that it is scalable to large systems since it uses distributed computing and that it allows for privacy of different components since one object does not need to know the models or methods of another object. Standardized and transportable objects representing physical components at various degrees of temporal, spatial, and functional granularity are constructed by different users and added to the SGRS platform for future use by all. This allows users to simulate and assess the effect of the technology of interest to them, which makes the SGRS effective in supporting the deployment of new technologies with wellunderstood effects. Examples on the SRGS are described for simulating market-driven sub-processes and the fast dynamics sub-processes in response to market actions and/or to sudden hard-to-predict disturbances.Keywords-Cyber Physical Systems (CPS) for energy systems; computer platforms; distributed simulations; event-driven simulations ; simulations-based smart grid test beds.

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