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The study is aimed at a lumped circuit‐based sizing of tubular‐linear synchronous machines (T‐LSMs) equipped by quasi‐Halbach magnetised PMs in the mover. The proposed approach is initiated by the synthesis the T‐LSM lumped circuit, taking into account: (i) the saturation of the magnetic circuit, (ii) the leakage fluxes, (iii) the armature magnetic reaction, and (iv) the variation of the mover position. Then, formulations of different no‐load and load operation features are derived in terms of selected variables yielded by the proposed lumped circuit. Among these features, the main value of the developed force is selected as a sizing criterion whose variation with respect to different influent design parameters is investigated along with the armature current density. The lumped circuit‐based sizing approach enables the selection of a set of appropriate design parameters for which the formulated no‐load and load operation features are predicted. A dual validation of the obtained results by an analytical model based on the air gap flux density formulation on one hand, and a 2D finite element analysis on the other hand, proves the effectiveness of the proposed sizing approach. [ABSTRACT FROM AUTHOR]

Linear machines are currently considered as viable candidates for direct-drive wave and free-piston energy converters. This paper is devoted to an approach based on a magnetic equivalent circuit (MEC), which is also called lumped circuit, dedicated to the modeling and sizing of a tubular linear permanent-magnet synchronous machine (T-LPMSM). The proposed approach considers, in a first step, the cancelation of the end-effect phenomenon. To do so, a dedicated design procedure, consisting in 1) achieving a $2\pi/3$-shift between the armature phase flux linkages by selecting a fractional ratio of the stator pole pitch to the mover one and 2) balancing the amplitudes of the phase flux linkages by extending the stator magnetic circuit with teeth of appropriate dimensions, is firmly applied on two basic T-LPMSM topologies using a dedicated MEC. Then, an investigation of the influent sizing parameters on the force production capability of the initial concept is carried out. The MEC-based prediction of the force requires the incorporation of the mover displacement, yielding the so-called “position varying MEC” on one hand and the armature magnetic reaction on the other hand. The finite-element analysis of the armature phase flux linkages and the developed force enable the validation of the results yielded by the established MECs. [ABSTRACT FROM AUTHOR]