Flux Permanent Magnet Generator Research Articles

Analytical Performance Estimation of a Fall-Back Inner-Rotor Transverse-Flux Permanent Magnet Generator using Magnetic Equivalent Reluctance Circuit

The potential of wind energy resources is propelled fast and power extraction is increasing considerably due to the development of reliable and cost-effective wind turbine generators. Various permanent magnet (PM) wind generators have been implemented for wind power generation, among which, the conventional transverse-flux permanent magnet generator (TFPMG) is popular due to their higher torque density and simple coil design, but it has some disadvantages in comparison with radial flux PM generator, i.e., higher flux leakages and complex 3D flux pattern. In this article, a fall-back inner rotor transverse-flux PM wind generator FB-TFPMG has been investigated to override the disadvantages of conventional TFPMG. It employs half of the total PMs on the rotor and U-shaped stator cores. An analytical model of the proposed FB-TFPMG has derived using magnetic equivalent reluctance circuit (MERC) to predict the performance of the generator, i.e., flux densities in the air-gap, under aligned and unaligned conditions of rotor PMs with U-shaped stator cores. The results of the MERC model is verified with the results obtained through 3D finite element analysis.

Multi‐objective optimisation design of air‐cored axial flux PM generator

The optimisation design of air-cored axial flux permanent magnet (PM) generator is a complex non-linear problem with constraints, multi-objective, multivariable and multi-peak value. The different variables will affect the same optimisation goal. In this paper, a multi-objective optimisation design of air-cored axial flux PM generator based on Taguchi-response surface method (RSM) is proposed. The main characteristics of generator efficiency, power quality, induction electromotive force and other main characteristics are taken as optimisation objectives. The parameter ranges that influence the optimisation objectives of the motor are selected as optimisation variables. First, the orthogonal matrix is established according to the number of selected parameters and the level factor of each parameter and the finite element method is used to solve the experimental matrix. Then, the mean and variance of the simulation results are analysed. The optimisation mathematical model was established between the target and the impact factor by using RSM for the conflicting factors, which can determine the optimal variable parameters. The effectiveness of the optimisation method is verified by finite element analysis and prototype experiments. The results show that the performance of optimised core less flux PM generator has been greatly improved.

Design and Performance Analysis of Double Stator Axial Flux PM Generator for Rim Driven Marine Current Turbines

This paper presents the design and performance analysis of double stator axial flux permanent magnet generators for rim-driven marine current turbines (MCT). In submarine applications, drive train reliability is a key feature for reducing maintenance requirements. Rim-driven, direct-drive, multistator generators can therefore be an interesting solution to improve reliability. In this context, the work presented here focuses on the design of a double-stator, axial flux, permanent magnet (PM) generator as a rim-driven, direct-drive, multistator generator. The models, specifications and an optimization procedure that facilitate the preliminary design of these kinds of generators for rim-driven marine turbines are presented. Validation with finite element computations and a performance analysis for a particular design of rim driven generators are conducted. The results obtained highlight some designs issues associated with PM generators for rim driven marine turbines. To assess the effectiveness of the double stator axial flux PM generator, a comparison with a surface mounted radial flux PM generator design for rim marine turbines is carried out. The comparison shows that the double stator axial flux generator has a better cooling characteristic and a reduced active parts cost and mass than the radial flux PM generator.

Theory of the adjustable speed generation systems

PurposeThe purpose of this paper is to provide a new theory of adjustable speed decoupled generation which has the potential to challenge existing coupled generation based on a classical synchronous generator operating with fixed speed.Design/methodology/approachThe paper's approach is a theoretical consideration of the drawbacks of conventional fixed speed generation based on a synchronous generator and proposal of problem solutions by the introduction of a decoupled generation system with additional degree of freedom. Computer calculations are used as design and for preliminary verification. Tests in a real laboratory system equipped with modern components such as electrical machines and power electronic converters proved the theory.FindingsDecoupled generation is realized in a very original way using new blocks, integration method and control. The developed system has been awarded more than six world patents. The system has additional degrees of freedom in speed and grid connection operation.Originality/valueThe research team has concentrated its research over many years and developed a generation system which has been awarded a great number of patents. A special axial flux, light and simple permanent magnet generator was developed and integrated to the prime mover. A three‐phase AC/AC power electronic converter and a DSP controller are integrated to a very small size and low weight. The invented topology provides a very reliable operation, high‐quality AC voltage in fully three‐phase non‐symmetrical load. There were also presentations on world conferences (EPE, PESC, EPE‐PEMC).