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A fully laminated shell-type three-phase rotating transformer, appropriate for the most brushless applications, is proposed. The stationary and rotary parts of the proposed machine include both radially and axially laminated magnetic cores. Thanks to the special construction, the mechanical assembling of the proposed device in an integrated three-phase unit is very simple. In addition, a high permeance, low eddy current magnetic path is provided for the magnetic flux in the machine volume. However, to limit the core eddy currents in a normal range, a special geometry is selected for the radially laminated parts. Using the transformer magnetic equivalent circuit, the self and mutual inductances are obtained analytically. Based on the developed analytical model, geometrical dimensions are selected such that, a balanced three-phase machine is provided. Finally, finite-element analysis and experimental results are used to verify the obtained analytical model. [ABSTRACT FROM AUTHOR]

This paper compares two methods to compute the parameters of a line-start synchronous reluctance (LSSR) machine, by means of finite element analysis. In both methods, both the impact of the skin effect on the rotor parameters and the impact of saturation on magnetizing inductances are taken into account. The first method is based on an equivalent single-phase model of the machine. A pulsating flux is imposed along the d- and q-axes separately, so as to compute the machine parameters along both d- and q-axes. Magnetizing inductances are achieved as a function of the flux, and the rotor resistances and leakage inductances are obtained as a function of rotor frequency. The second method is based on the d-q axis model of the LSSR machine. A rotating magnetic field is imposed, and the d-q axis parameters are estimated simultaneously from the field solution. In addition, such a method allows the cross-saturation to be considered as well. [ABSTRACT FROM PUBLISHER]