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Standstill Frequency Response (SSFR) testing and modeling of salient-pole synchronous machines are presented for two machines with integral and non-integral number of stator slots per pole per phase. Frequency responses at different rotor positions have been investigated to explore the effects of rotor position in a machine with fractional slot winding, as the electromagnetic fields and the armature magnetomotive forces do not precisely repeat every pole. The test results do not show any significant differences for various direct and quadrature axes rotor positions. The authors obtained a negative value of differential leakage inductance as theoretically postulated in the literature. The pertinent features of testing and modeling of salient-pole synchronous machines are described to point out the differences with SSFR testing of round rotor turbogenerators extensively published in the literature. Keywords: salient-pole synchronous machine, transfer functions, SSFR testing, equivalent circuit modeling, differential leakage inductance

The Magnetic Equivalent Circuit (MEC) method has been used to model the nonlinear magnetic field in electromagnetic devices for steady-state and dynamic conditions. However for highly saturated electromagnetic device, the conventional MEC method is inaccurate in predicting device characteristics. With experience gained from the Finite Element (FE) method, the MEC method can be modified to provide significant accuracy improvement in the field solution results. The main modification is done in the modeling of the highly saturated regions. The Improved Magnetic Equivalent Circuit (IMEC) is used to predict the characteristics of a Switched Reluctance Motor (SRM). The results from IMEC are compared with those obtained by conventional MEC, FE methods, and measurement. Index terms - Magnetic circuits, electromagnetic devices, nonlinear analysis.

In this paper, we report a way to condition the global stiffness matrix resulting from the Galerkin edge element formulation, in order to make the BICG solver converge for high Peclet number situations. The concept of artificial diffusion is introduced and extended to edge element cases. A general expression of the artificial diffusion scheme for 3D edge elements is derived and a numerical validation in 2D case is presented. It was observed that although nearly identical results were achieved both with or without introducing artificial parameters for a 2D test problem, the former provided a better conditioned global stiffness matrix to ensure the BICG's convergence.

This paper presents a 2-D electromagnetic field analysis of the single-sided linear induction motor (LIM), taking into account saturation in both primary and secondary cores. An analytical layer model has been developed in which the primary core is modeled by two different layers representing the yoke and teeth-slot regions. Such representation facilitates the evaluation of the magnetic state of the primary yoke and teeth separately. A new generalized mathematical formulation of a multilayer model is presented. The analytical computation results from a seven layer model correlate very well with experimental results obtained from an intermediate- capacity transit system LIM. The developed model is well-suited for sensitivity analysis and design studies.

Examines evidence for a seventh signature of a document by William Shakespeare. How William Lambarde's `Arxaionomia,' came into the possession of the Folger Library; Comparisons of the secretary and italic forms of handwriting used in Shakespeare's time.