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This article proposes an equivalent magnetic network (EMN) model to improve the accuracy of electromagnetic analysis, where a modular modelling of hybrid cross‐shaped mesh (CS‐M) elements is introduced. By applying hybrid CS‐M elements, the modelling of air gap and its surrounding regions is regulated into an identical width. As a result, the relative motion of the motor is simpler to simulate by changing the nodal connection without involving the non‐linear permeance. The airgap flux density is solved more accurately than the regular CS‐M elements as well. A 12‐slot/10‐pole ferrite permanent magnet (FPM) motor with assisted poles of unequal pole‐arc ratios is selected as an example to be built with the proposed EMN model. After solving the EMN model, the effectiveness and accuracy of the proposed EMN model are verified by comparing it with the FEA model and experiments. Additionally, based on the frozen permeability (FP) method, transient torque components can be separated accurately with a transient torque solution related to virtual work principle (VWP) for the EMN model. [ABSTRACT FROM AUTHOR]

This article proposes a practical design guide for a linear electromagnetic actuator based on the concept of magnetic screw transmission, in which manufacturing and assembly technologies are investigated. The surface-inserted design is first used to form a required helical-shape magnetic pole, which exhibits simple processing, high precision, and robust structure. Moreover, different topologies are developed using the 3-D finite-element analysis aided design, with the goal of optimizing thrust force. In addition, different number of permanent-magnet (PM) segments are first proposed to reduce the cogging effect. Afterward, the linear actuator integrates the rotary machine and the magnetic screw together to construct a compact design and decouples the magnetic circuits. The decoupling design focuses on the self-shielding effect of the Halbach PM array, and the special bearing supports are selected to avoid the eccentricity. Finally, a prototype is built using the developed techniques. Experiments are carried out on a linear test bench, verifying the theoretical analysis. [ABSTRACT FROM AUTHOR]

This paper proposes a new type of motor with hybrid permanent magnet material (HPMM); termed HPMM motor. The key of the proposed HPMM motor is the excitations, which combined rare-earth PM (REPM) with ferrite PM (FPM). To investigate the HPMM motor extensively, the HPMM motors with parallel magnetic circuit (PMC) and serial magnetic circuit (SMC) are designed. Because of the property difference between the REPM and the FPM, both PMC-HPMM motor and SMC-HPMM motor can offer low total harmonic distortion at high winding factor. Besides, the PMC-HPMM motor needs low consumption of REPM and offers low cogging torque, while the SMC-HPMM motor needs the extraordinary consumption of FPM, but offers little lower cogging torque. In addition, the reliabilities of both PMC-HPMM motor and SMC-HPMM motor are improved because of the single-layer concentrated winding and fault-tolerant teeth. Finally, the demagnetization of two motors has been studied, which indicates that the partial demagnetization will occur in the FPM. All these theoretical analyses are evaluated by the time-stepping finite element method. [ABSTRACT FROM AUTHOR]