Optimization of the Memory Employment for Studying Electrical Machines by Finite Element Method

Homo-heteropolar synchronous machine for low power variable speed wind or hydro applications: Design, 3D FEM validation and control

“…The binding relation between the orthogonal model's currents i d , i q and i 0 and the real machine's currents i a , i b and i c is [9]:…”

“…Thus in a stationary reference frame we have the two-axis model. Using the Park transformation for fluxes and currents, the expressions of the fluxes by axes d and q are obtained, ψ d and ψ q where L sσ is the own dispersion inductance, L 0 the inductance's constant component, L 2 the inductance dependent on the rotor's position, M 0 the coupling constant inductance, M E , M D , M Q the coupling maximum inductances between a stator phase and the excitation respectively damping winding D and Q [9], [10]:…”

“…Placing both the DC excitation coils and the three-phase AC winding on the stator characterizes this topology of homopolar (figure 1) [2,3], or homo-heteropolar synchronous machine (figure 2) [4][5][6]. The attractive advantages of this kind of machine are its better controllability in the very large speed range and the flexibility of the output generator characteristics [8,9]. Since the air-gap flux linkages created by the two stator windings and the induced rotor currents, the main air gap flux saturation phenomenon is more complicated than that of the normal synchronous machine [10].…”

“…Because of this complexity, a reconsideration of the main flux linkage saturation effect is called for in the design of the machine and in the development and practical implementation of speed/torque control algorithms. To avoid deep magnetic saturation in the stator core and teeth and rotor poles, magnetic design methodologies have been suggested both for the brushless homo-heteropolar synchronous machine [9], [10][11][12]. An approach to include the influence of magnetic saturation and iron loss using finite-element analysis in the performance prediction of the brushless homo-heteropolar synchronous machine was set.…”

An easy and fast 2D finite element program for studying the fields in three-phase transformers

“…It consists of the following operations: The required grid is automatically constructed by means of any number of overlapped rectangular grids all having the same base, and the number of triangular elements inserted in each grid can be chosen in a way completely independent of that of other grids.Since all the rectangular grids have the same base, the problem under examination must be studied by resorting to a grid greater than the domain under consideration, this grid containing both the actual grid and other “fictitious grids” which are relative to areas filled with air. Of course adequate physical parameters must be imposed to the triangular elements which are situated in the “fictitious grids”[4]. …”