• Journal of Electrical Engineering and Technology
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• v.6 no.2
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• pp.208-214
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• 2011

In this paper, a characteristics analysis and calculation of the suspending force of a novel bearingless switched reluctance motor (BLSRM) with hybrid stator poles is proposed. The operating principle and permeance are calculated to find an appropriate control scheme for a proposed motor. Furthermore, a mathematical model for suspending force is derived. Finite element analysis is also employed to compare with the expressions for suspending force. Finally, the validity of the structure and the mathematical model is verified by simulation results.

• Journal of Electrical Engineering and Technology
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• v.1 no.2
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• pp.185-191
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• 2006

In this paper, a novel stator hybrid excited doubly salient permanent magnet (SHEDS-PM) brushless machine with a special magnetic bridge is proposed for the first time. The originality of this machine is purposely to add a magnetic bridge in shunt with each PM pole, which not only maintains the stator lamination in its entireness, but also amplifies the effect of DC field flux on PM flux. An equivalent magnetic circuit is presented to clarify the novelty. Based on the 2-D finite element analysis, the static characteristics of the SHEDS-PM machine, namely phase flux linkage, back-EMF, cogging torque, winding inductance and static torque are deduced. The corresponding results on a prototype machine illustrate that the proposed machine is promising for application to electric vehicles.

• Journal of international Conference on Electrical Machines and Systems
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• v.1 no.4
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• pp.399-404
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• 2012

In this paper, a stator-separated axial flux-switching hybrid excitation synchronous machine (SSAFHESM) is presented, of which the structure and operational principle are introduced. The magnetic field distribution under different excited currents is analyzed, and some characteristics including flux-linkage, EMF and field control ability are studied by finite element analysis (FEA). Tests are carried out on a 12/10-pole prototype machine to validate the analysis results, and an excellent agreement is obtained.

• Journal of international Conference on Electrical Machines and Systems
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• v.1 no.3
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• pp.336-346
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• 2012

In this paper, a novel bearingless switched reluctance motor (BLSRM) with hybrid stator poles is proposed. The structure and operating principle are presented. In order to describe the design methodology clearly, analytical torque and radial force models are established. Further, basic design procedure is described. The numbers of phases and poles have important influence on the selection of structure. These effects, along with sizing of machine envelope and internal dimensions, make the machine design an insight-intensive effort. Effect of pole arcs and air-gap length on the production of torque and radial force are analyzed in detail. Mechanical design factors such as hoop stress and first critical speed are also considered. Based on the above analysis, the characteristics of the proposed BLSRM are analyzed. A prototype motor is designed and manufactured. The validity of the proposed structure is verified by the experimental results.

• Journal of Electrical Engineering and Technology
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• v.7 no.5
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• pp.705-713
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• 2012

In this paper, a novel 12/14 hybrid pole type bearingless switched reluctance motor (BLSRM) with short flux path and no flux-reversal in the stator is proposed. The proposed BLSRM has separated rotating torque and suspending force poles. Because of independent characteristics between torque and suspending force poles, the torque control can be decoupled from the suspending force control. Due to the short flux path without any reversal flux, compared to the 8/10 hybrid stator pole BLSRM, the output torque is significantly improved and the air-gap is easier to control. Meanwhile, basic design principle for the proposed structure is described. To verify the proposed structure, finite element method (FEM) is employed to get characteristics of the proposed structure and 8/10 hybrid stator pole BLSRM. Based on the analysis, a prototype of the proposed BLSRM is designed and manufactured. Finally, validity of the proposed structure is verified by the experimental results.

• Smart Structures and Systems
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• v.22 no.2
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• pp.139-150
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• 2018

A variable electromotive-force generator (VEG), which is a modified generator with an adjustable overlap between the rotor and the stator, is proposed to expand the operational range of a regular generator through a simple and robust active control strategy. It has a broad range of applications in hybrid vehicles, wind turbines, water turbines, and similar technologies. A mathematical model of the VEG is developed, and a novel prototype is designed and fabricated. The performance of the VEG with an active control system, which adjusts the overlap ratio based on the desired output power at different rotor speeds for a specific application, is theoretically and experimentally studied. The results show that reducing the overlap between the rotor and the stator of the generator results in reduced torque loss of the generator and an increased rotational speed of the generator rotor. A VEG can improve the fuel efficiency of hybrid vehicles; it can also expand operational ranges of wind turbines and water turbines and harness more power.

• Proceedings of the KIEE Conference
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• 1991.11a
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• pp.126-129
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• 1991

The effect of each tooth for optimal design of Hybrid permanent magnet step motor is presented on this paper. For this consideration, Hybrid permanent magnet step motor was designed in the first consideration tooth structure on the stator and the rotor and poles structure, as number of teeth on the stator and the rotor and slot depth and pitch of teeth, simulated by AutoLISP. During actual rotating, a chracteristic of Hybrid permanent magnet step motor which designed by AutoLISP program is considered. A chracteristic of Hybrid permanent magnet step motor is considered in change each variable, also. As a result, it was found that characteristic of Hybrid permanent magnet step motor changed in accordance with tooth structure and number of teeth and optimal design is possible by AutoLISP.

• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.51-54
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• 1991

The effect of inductance for optimal design of Hybrid permanent magnet step motor is presented on this paper. A pull-out torque of Hybrid permanent magnet step motor is measured and calculated by varying stator coil inductances, and power consumption of the step motor also is calculated and compared to the measured value. The relation of developed torque to parer consumption by the changing of magnetomotive force magnitude in a rotor permanent magnet is studied, which is the essence of the step motor design.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.5B no.3
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• pp.215-223
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• 2005

An electrical machine for a high-speed flywheel for energy storage in large hybrid electric vehicles is described. Design choices for the machine are motivated: it is a radial-flux external-rotor permanent-magnet synchronous machine without slots in the stator iron and with a shielding cylinder. An analytical model of the machine is briefly introduced whereafter optimization of the machine is discussed. Three optimization criteria were chosen: (1) torque; (2) total stator losses and (3) induced eddy current loss on the rotor. The influence of the following optimization variables on these criteria is investigated: (1) permanent-magnet array; (2) winding distribution and (3) machine geometry. The paper shows that an analytical model of the machine is very useful in optimization.

• Journal of Electrical Engineering and Technology
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• v.6 no.1
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• pp.94-103
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• 2011

This paper presents a novel bearingless switched reluctance motor (BLSRM) with decoupled torque and suspending stator poles. BLSRM is different from conventional bearingless switched reluctance motors (SRMs) because its suspending poles are separated from the torque poles. Perpendicularly placed suspending poles are designed to produce a continuous radial force to suspend the rotor. Due to the independent suspending and torque poles, BLSRM produces a suspending force with excellent linearity according to the rotor position and independent characteristics of the torque current. The air-gap is easier to control than in conventional SRMs with their linear and independent characteristics. Furthermore, to verify the proposed structure, a mathematical model for the suspending force is derived. Finite element analysis is also employed to compare BLSRM and conventional SRMs expressions of suspending force. A prototype motoris designed and manufactured to verify the effectiveness of the proposed bearingless structure.