Analysis of electromagnetic processes in a turbogenerator with equivalent stator tooth zones at no-load

: pp. 45-53
Lviv Polytechnic National University

While developing the mathematical field mo­dels of electric devices, to simplify the statement of the prob­lem, it is common to apply chain schemes and sub­s­ti­tute equivalent media for the complex structures of a con­struction. Identifying the influence of such sim­p­li­fi­ca­ti­ons on the conformity of the reproduction of elec­tro­mag­ne­tic processes by the models is an important problem, par­ti­cularly when the given methods concern zones that are the sources of an electromagnetic field in the objects. Be­sides, when developing the mathematical field mo­dels, the coordinate systems in which the process is con­si­dered are neglected. In this paper, 2-D mathematical field models for calculating a quasi-stationary elec­tro­mag­netic field in the cross-section of a turbogenerator at no-load with an equivalent stator zone are suggested. These models provide the calculation of the electromagnetic field in all zones of the device carried out on the basis of a vector potential in both the single coordinate system of the moving rotor, and the coordinate systems of the rotor and stator simulta­neously. The results obtained show that it is unacceptable to apply either substitution schemes or the equivalent replacement of the complex structures of elec­tric devices in the case when they are the sources of the elec­tromagnetic field in the object under investigation. Mo­reover, the analysis of the results confirms the ne­ces­si­ty to consider the systems of coordinates of movable and im­mo­vable media when developing mathematical field mo­dels of electrodynamic devices.

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