Showing 7 results for Axial Flux
F. Tootoonchian, K. Abbaszadeh, M. Ardebili,
Volume 8, Issue 3 (9-2012)
Abstract
Resolvers are widely used in electric driven systems especially in high precision servomechanisms. Both encapsulated and pancake resolvers suffer from a major drawback: static eccentricity (SE). This drawback causes a significant increase in resolver output position error (RPE) which could not be corrected electronically. To reduce RPE, this paper proposes a novel structure with axial flux. Proposed topology, design guidelines, optimization procedure and several key features to improve the sensitivity of axial flux resolver (AFR) against SE are studied. Furthermore, to minimize RPE an optimized design is attained. The machines are investigated in detail by using d-q model and 3D time stepping finite-element analysis. The results of theses two methods are compared and both prototype machines (proposed and optimized) are built. In order to evaluate proposed topologies, an experimental test setup is devised. Finally, the experimental results of the prototype machines verified the analysis results.
Mr Y Ebrahimi, Prof M.r Feyzi,
Volume 11, Issue 4 (12-2015)
Abstract
A novel structure of switched reluctance motors (SRMs) is proposed. The proposed structure uses the benefits of the axial flux path, short flux path, segmental rotor, and flux reversal free stator motors all together to improve the torque density of the SRMs. The main geometrical, electrical and physical specifications are presented. In addition, some features of the proposed structure are compared with those of a state-of-the-art radial flux SRM, considered as a reference motor. Then, the proposed structure is modified by employing a higher number of rotor segments than the stator modules and at the same time, reshaped stator modules tips. Achieved results reveal that, compared with the reference motor, the proposed and the modified proposed motors deliver about the same torque with 36.5% and 46.7% lower active material mass, respectively. The efficiency and torque production capability for the extended current densities are also retained. These make the proposed structures a potentially proper candidate for the electric vehicles (EVs) and hybrid electric vehicles (HEVs) as an in-wheel motor.
A. N. Patel, B. N. Suthar,
Volume 16, Issue 1 (3-2020)
Abstract
Cogging torque is the major limitation of axial flux permanent magnet motors. The reduction of cogging torque during the design process is highly desirable to enhance the overall performance of axial flux permanent magnet motors. This paper presents a double-layer magnet design technique for cogging torque reduction of axial flux permanent magnet motor. Initially, 250 W, 150 rpm axial flux brushless dc (BLDC) motor is designed for electric vehicle application. Initially designed reference axial flux BLDC motor is designed considering 48 stator slots and 16 rotor poles of NdFeb type single layer permanent magnet. Three-dimensional finite element modeling and analysis have been performed to obtain cogging torque profile of reference motor. Additional layer of the permanent magnet is created keeping usage of permanent magnet same with an objective of cogging torque reduction. Three-dimensional finite element modeling and analysis have been performed to obtain cogging torque profile of improved axial flux BLDC motor with double layer permanent magnet design. It is analyzed that double-layer magnet design is an effective technique to reduce the cogging torque of axial flux BLDC motor.
A. N. Patel, B. N. Suthar,
Volume 16, Issue 3 (9-2020)
Abstract
Optimization of specific power of axial flux permanent magnet brushless DC (PMBLDC) motor based on genetic algorithm optimization technique for an electric vehicle application is presented. Double rotor sandwiched stator topology of axial flux permanent magnet brushless DC motor is selected considering its best suitability in electric vehicle applications. Rating of electric motor is determined based on vehicular dynamics and application needs. Double rotor sandwiched stator axial flux PMBLDC motor is designed considering various assumed design variables. Initially designed axial flux PMBLDC motor is considered as a reference motor for further analysis. Optimization of the specific power of electric motor for electric vehicle applications is a very important design issue. The Genetic Algorithm (GA) based optimization technique is proposed for optimization of specific power of axial flux permanent magnet brushless DC motor. Optimization with an objective of maximum specific power with the same torque rating is performed. Three-dimensional finite element analysis is performed to validate the proposed GA based specific power optimization. Close agreement between results obtained from finite element analysis and analytical design establishes the correctness of the proposed optimization technique. The performance of the improved motor is compared with the initially designed reference motor. It is analyzed that the specific power of axial flux PMBLDC motor is enhanced effectively with the application of GA based design optimization technique.
Makan Torabi, Yousef Alinejad-Beromi,
Volume 19, Issue 4 (12-2023)
Abstract
A double-sided axial flux Permanent Magnet (PM) generator which can be directly driven by small-scale low-speed turbines is highly suitable for use in renewable energy generation systems. Partial demagnetization is a failure occurring under the high thermal operation of a Permanent Magnet machine. This paper focuses on partial demagnetization fault diagnosis in a double-rotor double-sided axial flux PM generator using stator currents analysis under time-varying conditions. One of the most important problems in any fault diagnosis approach is the investigation of load and speed variation on the proposed indices. To overcome the aforementioned problems, this paper adopts a novelty detection algorithm based on the Hilbert–Huang transform for fault diagnosis. This approach relies on two steps: estimating the intrinsic mode functions (IMFs) by the empirical mode decomposition (EMD) and computing the instantaneous amplitude (IA) and Instantaneous Frequency (IF) of IMFs using the Hilbert transform. The more significant IMFs are determined using the Hilbert spectrum, which is applied for accurate fault diagnosis. The Partial demagnetization severity can be evaluated based on the IMF’s energy value. The theoretical basis of the proposed method is presented. The effectiveness of the proposed method is verified by a series of simulation and experimental tests under different conditions.
Reza Mirzahosseini, Elham Rahimi Namaghi,
Volume 19, Issue 4 (12-2023)
Abstract
In this paper, a new topology of fractional slot concentrated winding double rotor axial flux permanent magnet synchronous motor (FSCW-DRAFPMSM) is introduced. The desired structure consists of a nonslotted stator core and two rotor discs. The pole number of the two rotors is different and these two rotors rotate at different speeds in opposite directions. A sample motor with an output power of 200 Watts is designed with the proposed structure. The two rotors of this sample motor rotate with speeds of 1200 and 857 rpm. The Finite Element Method (FEM) is employed to evaluate the performance of the proposed structure. Some performance characteristics of the case study machine, such as the Back EMF, input power, and electromagnetic torques of two rotors are presented to confirm the correctness of the operation of the proposed structure. In addition, the shifting technique is used to improve the Back EMF waveform of the machine. An analytical formula is proposed for calculating the fundamental component of the Back EMF waveform. The accuracy of the formula is approved by FEM.
Mehrdad Kamali, Behrooz Rezaeealam, Farhad Rezaee-Alam,
Volume 21, Issue 1 (3-2025)
Abstract
This paper investigates the operational performance of a novel Double-Rotor Hybrid Excitation Axial Flux Switching Permanent Magnet (DRHE-AFSPM) machine, combining the strengths of Flux-Switching Machines and Hybrid Excitation Synchronous Machines. The study analyzes the machine's structure and magnetic field adjustment principles, including inductance and flux linkage characteristics. A mathematical model is derived and a vector control-based drive system is established. The loading capacity of the DRHE-AFSPM motor is examined at low speeds using an id = 0 control approach based on a stage control strategy. For high-speed operation, a field-weakening control strategy is implemented, with the field-weakening moment determined based on the voltage difference. Simulations and experimental results demonstrate the DRHE-AFSPM motor's ability to fully utilize its torque with id = 0 control, highlighting its strong load capacity. Compared to speed-based field-weakening control strategies, the voltage difference-based approach offers improved inverter output voltage utilization and a broader speed regulation range. These findings suggest that the DRHE-AFSPM motor is a promising candidate for in-wheel motor applications in electric vehicles (EVs).
