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Wind energy as the cleanest source of renewable energy requires a highly efficient lightweight generator that provides maximum power density while having the least vibration noise and maintenance. In this study, an axial air gap transverse flux machine is presented, and all excitation sources are located in the stator. This structure provides lower core loss, weight and cost due to the full utilisation of the permanent magnets, SMC‐free structure and short magnetic flux path. In fact, by combining the features of a flux‐switching machine into a transverse flux generator with an axial air gap, it is possible to improve the performance of a direct‐drive wind turbine generator by overcoming traditional structures' challenges. To analyse the axial transverse flux switching permanent magnet generator performance characteristics, 3D finite element simulations have been performed, which have been validated by comparing them to the practical results of a single‐phase prototype. The results are in agreement with an acceptable error that is caused by manufacturing uncertainties. [ABSTRACT FROM AUTHOR]

Electrical machines are widely used in home appliances, the performance of which is mostly related to the quality function of the electrical machines. What has been used so far in home appliances brought with themselves a wide assortment of advantages and disadvantages. With the aim to overcome the drawbacks of the previously implemented electrical motors in washing machines, a new configuration of flux switching permanent magnet motor (FSPM) with the segmented outer rotor (SOR‐FSPM) is proposed benefitting from a direct driven drum. To reduce the cogging torque as well as torque ripple and to improve the total harmonic distortion, cutting the stator in a way to lower overlapping between the rotor and stator pole, inserting notches into the poles of the rotor to modify the air gap between the stator teeth and the rotor segments are proposed. The Taguchi method and sensitivity analysis are further applied to find the best combination set of changes in such a way to smoothen the chart showing reluctance between stator and rotor and fix the zero‐point crossing of the flux linkages in different rotor positions. Finally, the proposed SOR‐FSPM is prototyped, and experimental results along with the finite element method results are discussed and compared in order to verify the design process. [ABSTRACT FROM AUTHOR]

The multi‐layer switched reluctance motor (SRM) is a special type of the SRM which can be utilised appropriately in high‐power applications such as electric vehicle (EV). Thermal modelling of the multi‐layer SRM is considered for the first time in the present study and a lumped parameter thermal model is introduced for quick prediction of temperature rise in this motor. In the introduced lumped thermal model, independent thermal networks are considered for different parts of the machine including frame, stator yoke, stator pole, winding, air‐gap, end‐winding, end‐cap air, rotor pole, rotor core and shaft. All details of the modelling and the required equations are given and therefore someone can use the model easily. The developed thermal model is applied to a typical two‐layer 8/6 SRM and a prototyped three‐layer 8/8 SRM and the simulation results are then compared with those derived from three‐dimensional finite element (FE) method using ANSYS FE package and experimental results. These comparisons show well high computation speed and accuracy of the lumped thermal model developed for the multi‐layer SRM. [ABSTRACT FROM AUTHOR]

Rotor excited flux‐switching permanent magnet machines (REFSPMs) have been recently introduced exhibiting high power density and low permanent magnet consumption. Despite the advantages, 12/8 configuration of REFSPM has an intrinsic unbalanced voltage waveform due to the existence of even‐order harmonics. Aiming to improve the machine voltage THD, using notches on the rotor segments is proposed. To study the effects of the rotor notch on machine performance with low computational time, the non‐linear magnetic equivalent circuit is developed taking into account the effects of fringing fluxes, iron saturation, and rotor transition. An optimisation procedure based on Taguchi method is applied to minimise the voltage THD value taking the effects of uncontrollable factors into account. Finally, the REFSPM is prototyped and the measured results are compared with the analytical and numerical results. [ABSTRACT FROM AUTHOR]

Axial flux permanent magnet machines (AFPMs) are potential candidates for direct‐drive wind turbines (DDWTs) due to offering high value of torque density. In slotless AFPM topologies, the cogging torque is absent which makes them more suitable for DDWTs, which provides an easier turbine start‐up. In this research, a robust design and optimisation procedure of a slotless double‐sided AFPM is discussed. The non‐linear magnetic equivalent circuit is established and the optimisation is performed by the response surface methodology to achieve a cost‐effective generator with high power density value. The generator is prototyped and the test results are presented comparing them with the numerical study and non‐optimised design results. To minimise the AFPM torque ripple which is necessary for DDWT application, a cost‐effective solution is proposed leading to a dramatic improvement in the AFPM torque ripple without reducing the average torque. [ABSTRACT FROM AUTHOR]

Finding an optimally designed synchronous reluctance machine with desired performance among all possible combinations of the stator and rotor with different shapes of barriers requires long execution time, which is an overwhelming task. Selecting the number of flux barriers, for instance, in accordance with the pre‐designed stator has a significant effect on the torque ripple. To tackle these issues, this study presents a comprehensive design procedure of an external rotor synchronous reluctance machine suitable for an electric bike application that includes considerations such as electro‐magnetic and mechanical aspects. Dimensions of the internal stator with tapered slots are calculated. Additionally, a global parameter, insulation ratio in the q‐axis, is used to link the microscopic parameters. Seeking for the optimal design through the insulation ratio effectively reduced the number of geometric parameters involved in the rotor shape optimisation. The preliminary rotor design is used to run multi‐objective optimisation to provide further improvement to the average torque and torque ripple. Utilising the finite‐element method, thermal and structural analyses are conducted to guarantee the safe operation of the designed motor under a steady‐state condition. Finally, measurement results of a 250 W‐fabricated motor are compared with the predicted results, which validate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

A new switched reluctance motor for hybrid motion control is presented in this study. The motor can control both motions simultaneously and separately. A dedicated sensorless drive is developed for each kind of motion based on diagnostic pulse injection method. Eliminating the position sensors in the motor with two degrees of freedom reduces the manufacturing cost and complexity. Each kind of motion is controlled independently therefore no decoupling algorithm is required. The motor has been mainly designed to eliminate rotary to linear gears to be used as an automatic drilling tool. The cylindrical translators let simultaneous excitation of all coils on the linear stator and provide short magnetic flux paths which reduce the magnetic core losses and increase the force per volume. The motor design is verified initially by running three‐dimensional finite‐element analysis (FEA) on both rotary and linear sections. The motor is fabricated and tested in the lab utilising the sensorless drive. Accordance of experimental values with the FEA results certifies the performance and applicability of the motor. [ABSTRACT FROM AUTHOR]

A new structure for a hybrid motion switched-reluctance motor (SRM) is presented in this paper. The hybrid motion originated from the ability of the motor to operate in three modes: 1) rotary; 2) linear; and 3) rotary–linear, which can be named a new rotary–linear SRM. The design is in such a way that both rotary and linear motions can be controlled independently. The motor is composed of a three-phase 6/4 rotary SRM with Clockwise-Counterclockwise motions and a two-phase transverse flux linear SRM with forward–backward movements. The hybrid motion control does not need any decoupling control algorithm, which is an important issue in the other rotary–linear motors. In addition, a sensorless method for the motor control is provided. The motor design is performed based on the analytical approach. According to the obtained parameters, the motor 3-D model is utilized for electromagnetic assessment. The dynamic 3-D finite-element analysis is used to evaluate motor’s flux linkage, torque, speed, current, torque ripple, torque/speed, and force characteristics. The optimum operation is considered with choosing the proper dwell angle. To verify the design, a prototype is constructed in the laboratory and compared with other structures to show the performance and applicability of the proposed motor. [ABSTRACT FROM AUTHOR]

The double-stator switched reluctance motor (DSSRM) has a potential to produce more power per volume than other types of SRMs. This paper offers a new design strategy concentrating on power rating to calculate the dimensions of a DSSRM. The new strategy is based on dissecting the DSSRM into two inner and outer rotor SRMs. In this regard, both inner and outer rotor SRMs are designed separately, and then, the results are merged together. The characteristics of the DSSRM are achieved utilizing analytical design and 3-D finite-element analysis (FEA). In addition, the obtained results are compared with dual SRM. To determine the appropriate performance of the motor, the magnetic analysis is performed utilizing a 3-D model. In addition, to achieve optimal operation, two different winding configurations are investigated and compared with each other. Finally, a prototype of the flat-type cup-shape DSSRM with a segmented rotor is fabricated and tested in the laboratory. The results of the analytical calculations and the FEA are validated by a testing motor, which show the accuracy and the design strategy, and it can be extensible to other types of motors. [ABSTRACT FROM PUBLISHER]

This paper describes the magnetic characteristics and comprising results of two 15- 10 and 9-6 salient pole brushless dc machine with concentrated stator winding which does not use a permanent magnet in the rotor. The permanent magnet is replaced with assisted field coil in the rotor. To evaluate the generator performance, numerical analysis for both 15-10 and 9-6 Salient- Pole structure have been utilized. In the numerical analysis, 3-D Finite Element (FE) analysis has been carried out to confirm the accuracy of the predicted flux-linkage characteristics and, also an improved 3-D hybrid method coupling the FE method and boundary integral equation method to confirm the accuracy of the 3-D FE analysis has been carried out. Afterward, a series of experimental tests are performed to obtain the magnetic characteristics of the 9/6 configuration machine, comparing, correcting, and discussing the results with those of 3-D FEM analysis. [ABSTRACT FROM AUTHOR]