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This paper quantitatively compares two emerging stator-permanent-magnet (PM) machines, namely, the doubly salient PM and the PM hybrid brushless types. Both of them are attractive for electric vehicles and wind power generation. For comparison, both machines adopt the outer-rotor 36/24-pole topology and are designed based on the same peripheral dimensions. By using the circuit-field-torque time-stepping finite element analysis (CFT-TS-FEM), both steady-state and transient performances of the two machines are critically compared. Index Terms--Finite element method, machine analysis, machine design, permanent-magnet (PM) machine.

In this paper, a new double-stator cup-rotor permanent-magnet brushless DC (PMBDC) machine is proposed and analyzed. Since the machine structure is so unique while its operating principle is so distinct, a numerical field approach, namely the circuit-field-torque grid-model time-stepping finite-element method (CFT-GM-TS-FEM), is newly developed to analyze the steady-state and dynamic characteristics of the machine. Particularly, the analysis of eddy-current loss in both the PMs and iron core of the machine is conducted. Experimental results are given for verification. Index Terms--Eddy-current loss, finite-element method, permanent-magnet machine.

In this article, the balanced bidirectional-magnetization effect of a newly developed hybrid-magnet-circuit variable-flux memory machine (HMC-VFMM) is revealed and investigated. First, the machine topology and variable-flux principle of the HMC-VFMM are described. In addition, the balanced bidirectional-magnetization effect is analytically unveiled by using a Fourier-series-based hysteresis model of low coercive force (LCF) magnet. The PM magnetization characteristics are then investigated by a coupled solution, which is employed to identify the mismatch between the LCF magnet movement trajectories subject to either continuous one-way or bidirectional alternate current pulses. Finally, a prototype is manufactured and tested to verify the theoretical analyses. [ABSTRACT FROM AUTHOR]

In this paper, a new double-stator cup-rotor permanent-magnet machine is proposed and implemented for wind power generation. The design of unique double-stator configuration can improve the power density for easy installation, while the control of its winding connections can provide a constant output voltage over a wide range of wind speeds. The circuit-field-torque coupled time-stepping finite element method is utilized to analyze the proposed machine. Both analysis and experimental results are given to confirm the validity of the proposed machine. Index Terms--Cup rotor, double stator, finite element method, permanent-magnet machine, wind power.

In this paper, a new permanent magnet (PM) brushless hybrid machine is proposed and implemented for wind power generation. The originality is that a small dc field winding and an extra air-bridge are incorporated in the machine so that the air-gap flux can be effectively strengthened or weakened to online keep the output voltage constant throughout the whole wind speed range. The characteristics of flux linkage and no-load electromotive force (EMF) are analyzed by using the finite element method (FEM), and these results agree well with those from magnetic circuit analysis. Experimental results also verify that the proposed machine can produce a constant output voltage over a wide wind speed range. Index Terms--Finite element method (FEM), flux regulation, permanent magnet machine, wind power generation.

This paper proposes and implements a new three-phase 12/8-pole brushless doubly fed doubly salient machine (BDFDS) for wind power generation. The key is to design and control the proposed BDFDS machine in such a way that the system can offer constant output voltage and efficiency optimization over a wide range of wind speeds. First, the machine output power equation is derived to initialize the machine dimensions. Second, finite-element analysis is performed to finalize the machine dimensions as well as to determine the machine parameters and characteristics. Third, the system model is formulated and applied for computer simulation. Finally, the whole system is prototyped for verification, with emphasis on the constant voltage regulation and efficiency optimization. Index Terms--Brushless, doubly fed, doubly salient, wind power generation.