Periodicity and Growth in a Lattice Gas with Dynamical Geometry

We study a one-dimensional lattice gas "dynamical geometry model" in which local reversible interactions of counter-rotating groups of particles on a ring can create or destroy lattice sites. We exhibit many periodic orbits and and show that all other solutions have asymptotically growing lattice length in both directions of time. We explain why the length grows as $\sqrt{t}$ in all cases examined. We completely solve the dynamics for small numbers of particles with arbitrary initial conditions.Comment: 18 pages, LaTe

Analysis and Modeling of a Single-Phased Bifilar-Wound Brushless DG Motor

A single-phase brushless dc motor utilizing a bifilar stator winding and having asymmetrical stator pole faces is investigated. The form of the permanent-magnet component of the stator winding flux linkage is analyzed considering the asymmetry of the stator pole faces. Equations describing the electromechanical dynamics of the motor are then derived along with an expression for the electromagnetic torque. The requirements of the dc-to-ac inverter which drives the motor are determined. Using the expression for electromagnetic torque and inverter characteristics, the form of the so-called static electromagnetic torque is analyzed. The so-called cogging torque is established, and in conjunction with the static electromagnetic torque, used to explain the starting characteristics of the motor. The equations for the electromechanical dynamics are converted into state-model form and two mathematical models of the inverter are developed for use in a computer simulation. This computer simulation is then used to demonstrate steady-state and dynamic operation of the motor