Design Approach for a Novel Multi Material Variable Flux Synchronous Reluctance Machine without Rare Earth Magnets

Abstract

ÐA method to design a variable flux electric machine using no rare earth materials is proposed. Starting from a synchronous reluctance machine's rotor the electromagnetic and mechanical design goals are derived. To improve torque production radially magnetized low coercive field magnets are inserted in the rotor, allowing for a control of the rotor flux. The flux guidance is improved by removing the webs required for mechanical sturdiness, which is achieved instead by mold injecting fiber reinforced polymer into the flux barriers. On the basis of a large design of experiments and using Gaussian process regression models, the relation between the rotor design parameters and output torque as well as external fields in the magnets is investigated and an optimization is performed. The resulting machine design allows an operation with high torque without involuntary demagnetization. The potential of the polymer filled flux barriers is confirmed through structural mechanical analysis.Index TermsÐDesign of experiments, electric machines, finite element analysis, modeling, multi material design, optimization, reinforced polymers, rotor design, structural design This work was part of the research project ºReMosº (ºEffiziente Reluktanzmaschine fÈ ur effiziente MobilitÈ at ohne seltene Erdenº),financed through the Ministry of Science, Research, and Arts of the Federal State of Baden-WÈ urttemberg in the framework of ºInnovationscampus MobilitÈ at der Zukunftº.

Dynamic modeling of a synchronous reluctance machine for transient simulation of vibrations under variable rotor magnetization

“…Note, that Ãmag and K PM still depend on the fluxes ϕ instead of the auxiliary variable η. Since the mapping (22) is not unique, there exists no explicit way to write ϕ as a function of η. However, an implicit relation can be established by solving (24) for I and inserting into (18) yielding the algebraic equation…”

“…By substituting air with fiber-reinforced polymers, the rotor gains increased strength and resistance to mechanical stresses, thereby ensuring reliable performance and minimizing the risk of structural deformations or failures during operation and thus allowing for higher maximum speeds. 22 For the second project phase, the design and manufacturing of the motor prototype is done. The considered motor is a three-phase false( m = 3 false) synchronous motor with n s = 36 stator slots and a distributed stator coil winding, connected to result in six poles, that is, p = 3 pole pairs.…”

“…For the simulations in this contribution, the magnet model described in the “Magnetic circuit” section is parametrized according to the design presented in our previous work. 22 The characterizing parameters of the magnetic model are the lengths and cross sectional areas of the flux tubes represented by A l , A σ , l σ , A Fe , x, and l Fe , x , .1em x ∈ falsefalse{ St, T, R falsefalse}, the number of turns per stator coil n normalw, the constants α 1 , α 2, and α 3 of the nonlinear BH curve for μ r as well as the electric phase resistances R 1 , R 2, and R 3.…”

Quick Prediction of Losses During Magnetization State Changes in Variable Flux Machines

“…The machine design presented in [5] is investigated in this work. They key features of this machine are summarized below in table I.…”

“…the energy required to change the MS. While the design of VFM has been described and many propositions on design approaches have been made, namely in [2], [3], [4] and [5], only few authors consider the magnetization energy estimation. Furthermore, the machines presented in [2] - [4] focus on different than traction applications, as they usually have little to no reluctance torque and rely on magnet topologies employing single magnets.…”