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This paper proposes a new outer-rotor magnetless flux-switching DC-excited (FSDC) machine which can offer low-speed operation to directly capture the wind power for power generation. Compared with its permanent-magnet (PM) counterparts, the proposed machine equips no PM such that it enjoys the definite cost benefit. One of the key designs of the proposed machine is the multitoothed per stator pole structure. With the multitoothed structure, the proposed machine not only offers the fluxmodulation effect to boost up its torque density, but also is favorable for the low-speed operation. In addition, the external DC-field excitation can be controlled independently to offer the flux-controlled ability to achieve constant voltage output among various wind speeds. By performing the time-stepping finite element method (TS-FEM), the performances of the proposed machine can be analyzed, and hence verifying the design. [ABSTRACT FROM AUTHOR]

The permanent-magnet hybrid brushless (PMHB) motor adopts both DC field windings and PMs for excitation. It not only offers effective online flux control, but also flexible brushless DC (BLDC) or brushless AC (BLAC) operations. The key of this paper is to investigate two remedial strategies for fault-tolerant operations of the PMHB motor drive under open-circuit faults. First, by utilizing field excitation boosting, the reduced torque due to one phase loss can be remedied, the so-called remedial BLDC operation mode. Second, by reconstructing armature fields due to the healthy phase currents, the reduced torque can also be remedied, the so-called remedial BLAC operation mode. Finally, these two remedial operation modes are compared and verified by experimentation, hence confirming the validity of the proposed fault-tolerant PMHB motor drive. [ABSTRACT FROM AUTHOR]

With ever-increasing concerns on energy issues, the development of renewable energy sources is becoming more and more attractive. This paper first reviews both the wind power and photovoltaic (PV) power generation techniques and their maximum-power-point tracking (MPPT) methods. Then, a new stand-alone wind-PV hybrid generation system is proposed for application to remote and isolated areas. For the wind power generation branch, a new doubly excited permanent-magnet brushless machine is used to capture the maximum wind power by using online flux control. For the PV power generation branch, a single-ended primary inductance converter is adopted to harness the maximum solar power by tuning the duty cycle. The experimental results confirm that the proposed hybrid generation system can provide high efficiency with the use of MPPT. [ABSTRACT FROM AUTHOR]

With ever-increasing concerns on our enviromnent, there is a fast growing interest in electric vehicles (EVs) and hybrid EVs (REVs) from automakers, governments, and customers. As electric drives are the core of both EVs and HEVs, it is a pressing need for researchers to develop advanced electric-drive systems. In this paper, an overview of permanent-magnet (PM) brushless (BL) drives for EVs and HEVs is presented, with emphasis on machine topologies, drive operations, and control strategies. Then, three major research directions of the PM BL drive systems are elaborated, namely, the magnetic-geared outer-rotor PM BL drive system, the PM BL integrated starter-generator system, and the PM BL electric variable-transmission system. [ABSTRACT FROM AUTHOR]

This paper presents a hybrid excited doubly salient (HEDS) machine, which can be used as the integrated starter-generator (ISG) for modern automobile and hybrid electric vehicles (HEVs). The key of the proposed machine is to incorporate both direct current (dc) field windings and permanent magnets (PMs) in the stator, hence, offering a compact arrangement of hybrid field excitations, while the rotor is simply composed of salient poles without windings or PMs. The air-gap flux can be strengthened or weakened with a reasonable dc field current so that the electromagnetic torque and induced electromotive force (EMF) can be effectively regulated. To predict the electromagnetic performances of the machine more accurately, a new transient cosimulation approach considering indirect field-circuit coupling is proposed. Experimental results on a prototype machine have been given to verify the technique. The method is not only more efficient and flexible, but also more accurate and stable, which can also be used in analyzing other electric machine and drive systems. [ABSTRACT FROM AUTHOR]

This paper proposes a novel in-wheel motor, which artfully integrates a magnetic gear into a permanent-magnet brushless (PMBL) DC motor so that they can share a common PM rotor, hence offering both high efficiency and high power density. Moreover, the low-speed requirement for direct driving and the high-speed requirement for compact motor design can be achieved simultaneously. A 2-kW 600/4400-rpm magnetic-geared outer-rotor PMBL DC motor is designed and analyzed, which is particularly suitable for battery-powered electric motorcycles. [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. [ABSTRACT FROM AUTHOR]