Design and Realization of a Coreless and Magnetless Electric Motor Using Magnetic Resonant Coupling Technology

Liu, Ming; Chan, Ka Wing; Hu, Jiefeng; Lin, Qifang; Liu, Junwei; Xu, Wenzheng

doi:10.1109/tec.2019.2894865

Cited by 20 publications

(7 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A different method is applied in [21], where frequency splitting is used to create an excitation sequence in a multistator phase system. The generated torque is very small, and there is no analytical model of the motor parameters such as torque.…”

Section: Rotor Coils (Phase a And B Coils)mentioning

confidence: 99%

Design of a Coreless Multi-Phase Electric Motor Using Magnetic Resonant Coupling

Ebot

Fujimoto

2022

IEEE Trans. Magn.

View full text Add to dashboard Cite

With the emergence of electric vehicles and electric aircraft technologies, lightweight motors have become a requirement. Conventional motors are generally made up of coils, permanent magnets, heavy iron stators, and rotor cores. This paper presents complete analytical modeling and design of a novel coreless multi-phase magnetic resonant motor, conceptualized through the approach of magnetic resonance coupling. The removal of magnetic iron cores drastically reduces the weight of the resulting motor. The stator and rotor cores of the motor are made of reinforced plastic fibers and can be 3-D printed. Unrelated to the general operating principle of existing conventional electric motors, resonant wireless power transfer is the key feature of these motors. All the essential machine characteristics such as self-inductance, mutual inductance, torque, and frequency domains are fully developed. The mathematical modeling of the machine's physical phenomena is linked to its operation by simulation. The paper shows the design concept and discusses the simulation procedure used to verify the developed analytical model through finite element analysis from the established modeling topology equivalent to the proposed configuration motor model. Although the design is straightforward, accurate analytical modeling and analysis are significant challenges to consider.

show abstract

Section: Rotor Coils (Phase a And B Coils)mentioning

confidence: 99%

Design of a Coreless Multi-Phase Electric Motor Using Magnetic Resonant Coupling

Ebot

Fujimoto

2022

IEEE Trans. Magn.

View full text Add to dashboard Cite

show abstract

“…Analytic expressions for the inductances of ACRIMs can be found in [5] and [6], but they are derived under the assumption of two-dimensional (2-D) current sheet distributions or using the 2-D field solution of wires with round cross-sections, none of them is based on threedimensional (3-D) models, and therefore are not accurate for an air-cored machines. The Finite Element Analysis (FEA) method is used in [7] and [8] to extract ACRIM inductance values but it is still based on a 2-D model, so does not capture the important 3-D effects.…”

Section: Takedown Policymentioning

confidence: 99%

A Fast 3-D Winding Inductance Estimation Method for Air-Cored Resonant Induction Machines

Jin

Iacchetti

Smith

et al. 2022

IEEE Trans. on Ind. Applicat.

View full text Add to dashboard Cite

The air-cored resonant induction machine removes the magnetic core so the fields produced by the windings are truly 3-D in nature. The end-windings normally regarded as a non-active and leakage source in conventional iron-cored machines now become an active part and contribute to the torque production. Therefore, the electromagnetic modeling can no longer be reduced to a 2-D analysis and the 3-D inductance calculation becomes a key problem. The 3-D Finite Element Analysis (FEA) can solve the 3-D magnetic field but, firstly, the validity of its solution depends on the precision in geometry modeling. In particular, representing the end-winding region avoiding conductor clashing can be very complicated. Secondly, 3-D FEA solutions are computationally-slow and therefore inefficient as an "internal routine" of an optimization procedure. This paper proposes a fast analytic 3-D winding inductance estimation method for air-cored resonant induction machines. The approach breaks down the real coils into straight conductors and represents them by single filaments located at their centers, then uses closed-form expressions derived from Neumann integrals to calculate the coil self and coil-to-coil mutual inductances which are then collected into winding phase self and mutual inductances. All the independent coil-pair contributions are isolated so as to eliminate redundant calculations. Good accuracy of the calculated results is confirmed by validation against both 3-D FEA and experimental results, including winding inductance breakdown and overall machine tested performance.

show abstract

“…Equations ( 4)-( 7) are used for finding the maximum efficiency point in the design optimization routine. However, applying (4)- (7) requires the machine parameters to be estimated first.…”

Section: Peak-efficiency Pointsmentioning

confidence: 99%

“…The optimization program starts from an initial set of (rbs, rbr, as, ar, Ns) within their lower and upper bounds, then calculates the equivalent circuit parameters based on the design variables and pre-set values. Consequently, the motoring-mode peak-efficiency points (sη, ηpk) for tuning options I and II can be computed using ( 4)- (7). The prescribed slip s0 is then known and the capacitances are tuned to resonate at the peak-efficiency slip, i.e., s0 = sη.…”

Section: B Optimization Proceduresmentioning

confidence: 99%

“…[6] reports an experimental validation of an axial-flux ACRIM but only with a locked rotor. [7] proposes an ACRIM topology utilizing the frequency splitting phenomenon: the supply frequency is adjusted in accordance with the rotor position to produce attractive and repulsive forces between the stator and rotor. 2-D FE validations are included in the paper but only for a stationary rotor fixed at different angles and no experimental confirmation is provided for the operating principle.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Design Optimization Procedure of Air-Cored Resonant Induction Machines

Jin

Iacchetti

Smith

et al. 2021

2021 IEEE Energy Conversion Congress and Exposition (ECCE)

View full text Add to dashboard Cite

The air-cored resonant induction machine removes the iron core which makes its magnetic field truly 3-D in nature. The axial conductors and end windings now both become active components contributing to torque production. The whole winding therefore needs to be considered in the design process. Conventional 3-D finite element analysis has large computational costs and is hard to integrate into the design optimization. This paper presents a new design optimization procedure for air-cored resonant induction machines using closed-form solutions of Neumann integrals which are computationally fast and considers the 3-D magnetic field distributions created by the air-cored coils. Optimized designs for two tuning options in the literature: option I with stator capacitors only and option II with both stator and rotor capacitors, are presented. The optimization trends with respect to different machine parameters are also discussed.

show abstract

Design and Realization of a Coreless and Magnetless Electric Motor Using Magnetic Resonant Coupling Technology

Cited by 20 publications

References 24 publications

Design of a Coreless Multi-Phase Electric Motor Using Magnetic Resonant Coupling

Design of a Coreless Multi-Phase Electric Motor Using Magnetic Resonant Coupling

A Fast 3-D Winding Inductance Estimation Method for Air-Cored Resonant Induction Machines

Design Optimization Procedure of Air-Cored Resonant Induction Machines

Contact Info

Product

Resources

About