Performance and cost comparison of permanent-magnet vernier machines

published_or_final_versio

Complex-conjugate control of a linear magnetic-geared permanent-magnet machine for Archimedes wave swing based power generation

Paper no. YF-005177This paper deals with control of a linear magnetic-geared permanent-magnet machine for Archimedes wave swing based wave power generation using maximum power point tracking (MPPT). Firstly, the linear magnetic-geared permanent-magnet generator structure is presented. The machine modeling is established based on finite element analysis (FEA). Secondly, by analyzing the dynamic model of wave power, the MPPT algorithm for direct-drive wave power generation is developed. Then, the performance for maximizing wave power absorption is verified and evaluated by the circuit simulator. The results verify that the MPPT algorithm is valid for the direct-drive wave power generation. © 2015 IEEE.postprin

Simulation of a linear permanent magnet vernier machine for direct-drive wave power generation

This paper proposes a linear permanent magnet (PM) vernier machine for direct-drive wave power generation. Firstly, the machine structure is proposed and its parameters are indentified by finite element analysis (FEA). Secondly, the mathematical modeling of wave power absorption system was established. The control strategy for maximizing absorbed wave power is discussed. Then, by using Matlab/Simulink, the wave power generator system is modeled and simulated. A vector control scheme is implemented which controls power flow between the generator and the load via a bi-directional AC/DC converter. The simulation results verify the feasibility of the proposed machine used for direct-drive wave power generation. © 2011 IEEE.published_or_final_versionThe 2011 International Conference on Electrical Machines and Systems (ICEMS 2011), Beijing, China, 20-23 August 2011. In Proceedings of ICEMS, 2011, p. 1-

Design and qnalysis of a novel linear transverse flux permanent magnet motor using HTS magnetic shielding

In this paper, a novel linear transverse flux permanent magnet (TFPM) motor is proposed, which can offer higher thrust force, lower cogging force and easier manufacturing than its counterpart. The key is to propose a new C-shaped TFPM motor topology with the use of HTS bulks. After deriving the expressions of cogging force and thrust force, the proposed motor can be designed with minimum cogging force and maximum thrust force. Then, by employing finite element analysis, the advantages and validity of the proposed motor are verified. © 2006 IEEE.published_or_final_versio

Harmonic analysis and comparison of permanent magnet vernier and magnetic-geared machines

The IEEE International Magnetic Conference (INTERMAG2011), Taipei, Taiwan, 25-29 April 2011.In this paper, harmonic analysis and comparison of permanent magnet vernier (PMV) and magnetic-geared (MGd) machines are presented. The key is to analytically solve the governing Laplacian/quasi-Poissonian field equations in the air-gap regions. By using the time-stepping finite-element method, the analytical method is verified. Hence, the performances of the PMV machine are quantitatively compared with that of the MGd machine. The results show that the PMV machine can offer higher no-load EMF and higher torque-handling capability than its counterpart. Finally, the experimental result is given to further verify the validity of the analysis. © 2011 IEEE.published_or_final_versio

Design and analysis of a HTS vernier PM machine

This paper proposes a novel high-temperature superconductor (HTS) vernier permanent-magnet machine which can offer low-speed high-torque operation under line frequency. The key is to newly introduce the flux-modulation poles which modulate the high-speed rotating field in the stator to become the low-speed rotating field in the airgap. Also, the use of HTS armature windings can greatly reduce the power loss and improve the power density. By using the time-stepping finite element method, the machine performances are analyzed. Hence, the validity of the proposed machine is verified. © 2006 IEEE.published_or_final_versio

A novel HTS-PM vernier motor for direct-drive propulsion

In this paper, a novel high-temperature superconductor (HTS) permanent magnet (PM) vernier motor is proposed for direct-drive propulsion, which can directly offer the low-speed high-torque capability and the high-speed rotating field design to eliminate the gearing mechanism and maximize the power density, respectively. The key is to newly introduce HTS bulks to flux-modulation poles that can effectively modulate between the high-speed rotating field of armature windings and the low-speed rotating field of the PM outer rotor. Also, the use of HTS bulks can greatly reduce the flux leakage and hence improve the torque density. Based on using the finite element method, the motor performances are analysed. Hence, the validity of the proposed motor is verified. © 2010 IEEE.published_or_final_versio

Simulation of a tubular linear magnetic gear using HTS bulks for field modulation

paper no. 4LPD-01A tubular linear magnetic gear is proposed, which newly utilizes high temperature superconductor (HTS) bulks for its field modulation. Compared to the conventional one, the proposed topology can significantly reduce the leakage flux, hence improving its force transmission capacity. By using the magnetic circuit modeling, the analytical formulae of air-gap flux density and thrust force are firstly derived. Then, the finite element method (FEM) is employed to validate the performance of the proposed linear magnetic gear. © 2010 IEEE.published_or_final_versio

Eddy-current analysis of double-stator inset-type permanent magnet brushless machines

In this paper, a new multi-pole double-stator inset-type permanent magnet (PM) machine is proposed for low-speed direct-drive applications. In the outer stator, a fractional-slot concentrated winding is adopted to reduce the slot number and stator yoke height, hence saving the space and improving the torque density. In the inner stator, a vernier structure is used to reduce the winding slots and enlarge the slot area to accommodate more conductors, hence fully utilizing the inner stator space. Consequently, the torque density is improved, and the cogging torque is reduced. Since the machine structure is so unique while its operating principle is so distinct, a nodal method based network-field coupled time-stepping finite element method (NF-TS-FEM) is newly developed. The corresponding modeling and analysis are simpler and more convenient than its loop method based counterpart. The analysis of eddy-current loss in both of the PMs is conducted. The performance of the proposed machine is verified by the proposed NF-TS-FEM. © 2006 IEEE.published_or_final_versio

A novel coaxial magnetic gear using bulk HTS for industrial applications

In this paper, a novel coaxial magnetic gear (CMG) using bulk high temperature superconductors (HTS) is proposed. By substituting bulk HTS for ferromagnetic material, a novel stationary ring is resulted, which can not only provide the desired field modulation effect but also suppress the end-effects that commonly occurred in the traditional CMG. The performance of the proposed bulk HTS CMG is assessed and then verified by using finite element analysis. © 2006 IEEE.published_or_final_versio