Motor Geometry Research Articles

Design Modification and Analysis of Brushless Direct-Current Axial Fan Motor Stator Using Taguchi and One-Factor-At-A-Time Method

This paper introduces a novel approach utilizing Altair Flux software for electromagnetic finite element simulation and analyses of cogging torque and back electromotive force (BEMF) without altering the rotor conditions. This investigation aims to understand the effects on the design of brushless direct current (BLDC) axial fan motors. The Altair HyperStudy optimal software is used to conduct the Taguchi experimental method to analyze the influence of critical factors in motor stator design. Subsequently, the one-factor-at-a-time method proposed in this paper is applied to find the optimal motor geometry stator design satisfying the requirements. Eventually, an experimental motor is established and compared with a commercial 9SG5748P5G01 BLDC axial fan motor. The BEMF is resultantly smaller than the 9SG5748P5G01 motor. Furthermore, the disparity between the experimental and simulation analysis results is minimal with consistent findings. The motor stator design and simulation analysis methods can potentially support the motor design.

A differentiable dynamic modeling approach to integrated motion planning and actuator physical design for mobile manipulators

AbstractThis paper investigates the differentiable dynamic modeling of mobile manipulators to facilitate efficient motion planning and physical design of actuators, where the actuator design is parameterized by physically meaningful motor geometry parameters. The proposed differentiable modeling comprises two major components. First, the dynamic model of the mobile manipulator is derived, which differs from the state‐of‐the‐art in two aspects: (1) the model parameters, including magnetic flux, link mass, inertia, and center‐of‐mass, are represented as analytical functions of actuator design parameters; (2) the dynamic coupling between the base and the manipulator is captured. Second, the state and control constraints, such as maximum angular velocity and torque capacity, are established as analytical functions of actuator design parameters. This paper further showcases two typical use cases of the proposed differentiable modeling work: integrated locomotion and manipulation planning; simultaneous actuator design and motion planning. Numerical experiments demonstrate the effectiveness of differentiable modeling. That is, for motion planning, it can effectively reduce computation time as well as result in shorter task completion time and lower energy consumption, compared with an established sequential motion planning approach. Furthermore, actuator design and motion planning can be jointly optimized toward higher performance.

Phenomenological regression rate model in axial injection end-burning hybrid rocket motor using different oxidizers

Compared with conventional configurations, axial-injection end-burning hybrid rocket motors work with multiport fuel grains, which mainly burn in the axial direction. The consumption rate is controlled by the several flames developed at the end of each port. Although many studies of performance and flame stability have been carried out in the past, a phenomenological model of the axial regression rate was never provided in the past, which is the objective of the current work. The validation of the physical model is performed by a comparative study between firing tests using gaseous oxygen and nitrous oxide. Two experimental campaigns performed by a pressure-controlled combustion chamber are carried out with a single port grain in operative conditions equivalent to the multiport configuration. The axial regression rate was measured by varying the port diameter in a range between 0.5 and 4.6 mm, the mass flow rate between 0.004 and 1.7 g/s, and the chamber pressure between 0.1 and 3.4 MPa. The measured axial regression rate was quantitatively lower with nitrous oxide than oxygen, and the pressure sensitivity exponent decreased from 1.85 to 1.5, respectively. The physical reason has been attributed to the decomposition reaction of nitrous oxide occurring upstream of the flame front. In addition, a general methodology for fuel grain design is given, highlighting the benefits and drawbacks of introducing multiport grains and the effect of the oxidizer choice on the motor geometry. Finally, multiport firing tests were carried out to confirm the evidence observed in the simplified single-port campaigns.

Design Optimisation Approach of an Outer Rotor Multiphase PM Actuator for Multirotor Aerial Vehicle Applications

The electric urban air mobility sector has gained significant attraction in public debates, particularly with the proliferation of announcements demonstrating new aerial vehicles and the infrastructure that goes with them. In this context, the development of new methodologies for the design and sizing of actuation systems, ensuring high performances of these aerial vehicles, remains an important task in this process. This will allow for better integration within this transport sector. In this paper, a robust design optimisation approach of multiphase fault-tolerant (FT) outer rotor (OR) permanent magnets (PM) for multirotor aerial vehicle applications is proposed. In order to show the effectiveness and the robustness of the proposed design methodology, the number of stator winding phases, with a fractional slot concentrated winding (FSCW) configuration, as well as the PM configuration are considered as variables. Thus, four cases for the number of phases are considered, namely 3, 5, 6 and 7 phases, where for each number of phases case, the PM takes 3 configurations, namely surface PM, interior V-shape PM and interior spoke PM. First, a pre-sizing step is carried out, consisting of selecting the optimal combinations slot/pole, designing the multiphase FSCW layout, and estimating the electric motor (EM) geometry using analytical computations to obtain a preliminary validation of the design specifications. Second, constrained multiobjective optimisation is considered in order to optimise the EM performances, such as motor efficiency and weight, under constraints where the FEMM/Matlab based Finite Element Analysis (FEA) tool is used to perform this optimisation. Finally, results analysis and performance comparisons of different EM configurations are carried out in order to assess the design parameters, such as phases number, PM position, and harmonic currents in the EM design and consequently to select the best configuration for the considered application.

Design and Co-Analysis of A Permanent Magnet Brushless DC Motor By Using Clonal Selection Principle Based Wound Healing Algorithm and Ansys-Maxwell

This paper presents the design and analysis of a 550 W Permanent Magnet (PM) Brushless DC motor (BLDC). The finite element method (FEM) was employed to assess the motor's performance characteristics. The design and dynamic performance analysis were conducted using ANSYS/Rmxprt, while electromagnetic studies were carried out using ANSYS/Maxwell-2D. Additionally, optimization of the DC motor was achieved through a Wound Healing Algorithm (WHA). A PID controller was designed for this purpose. The paper also elaborates on the detailed design equations for creating a BLDC motor. BLDC motors are known for their high dynamic responses, efficiency, extended operating life, wide speed change intervals, and noise-free operation. The motor's geometry was modeled in the ANSYS-Maxwell-Rmxprt software tool and later imported into the Maxwell-2D environment for further analysis. The designed motor was observed to operate with 93% efficiency, meeting the specified torque value. The results of the optimization process were interpreted by comparing them with the values obtained from the ANSYS software.

Cooling Strategy Optimization of a Permanent Magnet Synchronous Motor

In this study, 250 kW, 9 phase, outer rotor types of Permanent Magnet Synchronous Motor (PMSM) are taken into consideration. To optimize the cooling efficiency of the motor, firstly, the motor geometry is obtained, and the e-magnetic model of the geometry is validated with the manufacturer`s data. Secondly, by using the validated e-magnetic model, the cooling system of the motor was analyzed by using the thermal model of the Motor-CAD. The thermal model is also validated with the real-time experiments which are held on an electric bus at constant speed experimentally. For finding the best cooling strategy for the motor, after validation, the effect of the mass flow rate, the type of the cooling refrigerant, the cooling pipe diameter size, and the change of torque are analyzed on the validated model. The results showed us that mass flow rate and torque have a significant effect on winding temperature, and the Taguchi method showed that [mass flow rate (A)=50 l/min, pipe diameter (B) = 17.7 mm, number of turns (C)=20, type of fluid (D)= EGW50/50, torque (E)=2000 Nm] is the best cooling design parameters for the cooling strategy of the considered PMSM.

Optimization of the Lifetime and Cost of a PMSM in an Electric Vehicle Drive Train

This study focuses on optimizing the lifetime and cost of an electric vehicle powertrain by optimizing the motor’s geometrical parameters and the bus voltage while considering the battery’s sizing. We employ the WLTP driving cycle to evaluate the powertrain’s performance and use finite element and analytical modeling to consider electromagnetic, thermal, and aging behaviors. Our research investigates the interplay between the battery and motor, exploring how varying the motor geometry and parameters affects the powertrain’s overall lifetime and cost. Our findings will contribute to developing more efficient and cost-effective electric powertrains.

Parallel-in-time optimization of induction motors

Parallel-in-time (PinT) methods were developed to accelerate time-domain solution of evolutionary problems using modern parallel computer architectures. In this paper we incorporate one of the efficient PinT approaches, in particular, the asynchronous truncated multigrid-reduction-in-time algorithm, into a bound constrained optimization procedure applied to an induction machine. Calculation of an optimal motor geometry with respect to its efficiency in the steady state is thus parallelized at each iteration of the optimization algorithm. As a result, a more efficient motor model is obtained about 11 times faster compared to optimization using the standard sequential time stepping.

Magnetic equivalent circuit and finite element modelling of anisotropic rotor axial flux permanent magnet synchronous motors with fractional slot distributed winding

AbstractAxial flux motors have been in the focus of many research work due to their promising properties when compared to conventional radial flux machines. Axial flux permanent magnet synchronous motors (AFPMSM) studied in the literature were mostly limited to surface‐mounted permanent magnet machines (SPMSM), excluding only a few studies about axial flux internal permanent magnet (AFIPM) or permanent magnet‐assisted synchronous reluctance (AFPMaSynRM) machines. Since numerous rotor topologies have been proposed and investigated in case of radial flux motors, analogous design methodologies can be developed in case of axial flux motors with rotor saliency. The parametrisation and modelling of a magnetically anisotropic rotor axial flux motor are presented. This approach is described generally and the method is applied to an example motor geometry. The results were validated by FEA (Finite Element Analysis), using the 2D multi‐slice and 3D modelling approaches. The modelling error was calculated and the analytical and numerical methods were compared. It was found that the proposed model was suitable for calculating important parameters of the anisotropic rotor axial flux permanent magnet synchronous motor (AnR‐AFPMSM) during the design process.

Elucidating mechanisms of cytoskeletal ensemble synergy using optical tweezers.

Development of cytoskeletal reconstitution assays that reflect a physiologically relevant environment has been a challenge for the biophysics field. In particular, optical trapping approaches to investigate motor protein dynamics have typically consisted of a reductionist geometry of a single motor and single filament. These assays not only do not capture the structural hierarchy in which motors with crosslinking ability function, but they also cannot capture the emergent mechanics that develop from ensembles of cytoskeletal proteins. It is becoming increasingly clear that the sum of protein single molecule properties may not always equal the resulting mechanics of the overall ensemble. Thus, to probe the molecular determinants of force generation, communication, and synergy of hierarchical cytoskeletal mechanics with high resolution, an optical trapping approach was developed that probes multiple motors and filaments in an ensemble. Using this method, we interrogate actomyosin mechanics to elucidate myosin II ensemble synergy and force regulation within a bundled actin assembly.

Technical and Economic Analysis to Select Suitable Design Parameters of an E-Machine for Electric Commercial Vehicles

In the European Union (EU), road transport contributes a major proportion of the total greenhouse gas (GHG) emissions, of which a significant amount is caused by heavy-duty commercial vehicles (CV). The increasing number of emission regulations and penalties by the EU have forced commercial vehicle manufacturers to investigate powertrain technologies other than conventional internal combustion engines (ICE). Since vehicle economics plays an important role in purchase decisions and the powertrain of a battery electric vehicle (BEV) contributes to about 8–20% of the total vehicle cost and the electric machine (EM) alone contributes to 33–43% of the drivetrain cost, it is necessary to analyze suitable EM topologies for the powertrain. In this paper, the authors aim to analyze the technical and cost aspects of an EM for electric commercial vehicles (ECV). Based on prior research and literature on this subject, an appropriate methodology for selecting suitable geometrical parameters of an e-machine for the use case of a heavy-duty vehicle is developed using MATLAB and Simulink tools. Then, for the economic analysis of the e-machine, reference ones are used, and their design parameters and cost structures are utilized to develop a cost function. Different use cases are evaluated according to the vehicle’s application. The results for a use case are compared by varying the design parameters to find the most cost-effective EM. Later, an analysis is performed on other decisive factors for EM selection. This highlights the importance of collaborative consideration of technological as well as the economic aspects of EMs for different use cases in ECVs. The method developed in this work contributes to understand the economic aspect of EMs as well as considering their performance factors. State-of-the-art methods and research are used to develop a novel methodology that helps with the selection of the initial geometry of the electric motor during the design process, which can serve to aid future designers and converters of electric heavy-duty vehicles.

Sizing of the Motor Geometry for an Electric Aircraft Propulsion Switched Reluctance Machine Using a Reluctance Mesh-Based Magnetic Equivalent Circuit

The switched reluctance motor (SRM) is a promising candidate for electric propulsion systems. In the design process of an SRM, the motor geometry needs to be determined. Using the finite element method (FEM) might be time-consuming for the sizing of the motor geometry. As an alternative, electromagnetic models based on a magnetic equivalent circuit (MEC) can be utilized for the sizing of an SRM. MEC models require fewer computational resources and can help determine the electromagnetic performance with reasonable accuracy. Using the conventional MEC method for SRM sizing might be challenging since the flux pattern inside the motor should be changed for different motor dimensions. In order to address this challenge, this paper applies a reluctance mesh-based MEC technique to determine the geometry of a three-phase 12/16 SRM for a high-lift motor in the NASA Maxwell X-57 electric aircraft. A comprehensive reluctance mesh-based MEC model is developed for this purpose. Both the static and dynamic characteristics of the SRM geometry are evaluated using the reluctance mesh-based MEC method. The determined geometry is verified using the results computed from FEM.

Retracted] Numerical Sensing and Simulation Analysis of Three‐Dimensional Flow Field and Temperature Field of Submersible Motor

In order to accurately study the temperature field distribution of the submersible motor, the author proposes the numerical sensing and simulation analysis of the three‐dimensional flow field and temperature field of the submersible motor. For a marine air gap water‐cooled internal submersible permanent magnet motor, based on the principle of computational fluid dynamics (CFD), numerical simulation analysis and geometric structure improvement of the three‐dimensional flow field and temperature field of the motor were carried out, eliminate the reverse flow phenomenon in the internal flow field of the motor, improve the heat dissipation efficiency of the whole machine, and optimize the flow field and temperature rise of the motor. Experimental results show that after the motor geometry is optimized, the flow rate of the cooling water in the air gap channel is 36.7 L/min, which is 7.9 L/min higher than the original model, it means that the heat in the motor can be better carried away by the water flow in the air gap channel. It is proved that the results obtained in this study have certain reference significance for the geometric structure design of the submersible motor.

An Innovative Approach to Electrical Motor Geometry Generation Using Machine Learning and Image Processing Techniques

This paper presents a methodology for generating geometries for interior permanent magnet (IPM) motors in electric vehicles (EVs) through the application of artificial intelligence (AI) and image processing (IP) techniques. Due to the implementation of green agreements and policies aimed at reducing greenhouse gas emissions, EVs have become popularity. As a consequence, the improvement studies on the powertrain and battery system of EVs are focused. Especially for the powertrain, design optimization studies of e-motor have increased in the literature. One of the most widely used e-motor topologies is interior permanent magnet (IPM) motor. However, designing the IPM motor presents a challenge due to the dynamic considerations with geometric constraints. Therefore, e-motor designers encounter challenges related to determining initial geometry and the long time of the optimization process. To address these challenges, a novel approach is proposed that leverages machine learning (ML) techniques in combination with IP to generate initial geometries and design parameters for IPM motors. The proposed approach generates images of the motor geometry and extract dimensional features from the resulting images by using artificial neural networks (ANNs). The proposed method performs an analysis of the input vectors to reduce their size using techniques such as Histogram, 2D Maximum, 2D Mean, 2D Minimum, 2D Standard Deviation, and 2D Variance to enhance feature extraction. Additionally, FFT (Fast Fourier Transform) and IFFT (Inverse Fast Fourier Transform) are used to improve the neural network process in generating the image geometry. Further, the generated image geometry is improved by applying digital filtering techniques such as Log, FFT, Log+FFT, Laplacian, Sobel, and Histogram Equalization. Finally, the trained ANNs are tested to validate the results by using Ansys RMXprt and Maxwell. Eventually, the proposed method represents an innovative solution to generating initial geometries for IPM motors in EVs that satisfies desired design requirements. This approach leverages the power of AI and image processing techniques, which could lead to significant improvements in the optimization process for IPM motors, accelerate the designer’s analysis process, and enhance the performance of EVs.

Development of a design system for synthesis and analysis the motor wheel based on a valve electric motor of combined excitation for hybrid and electric vehicles

The article describes a project to create an electric transmission for ground vehicles. As a layout, a motor-wheel variant is proposed, in which a traction electric motor, power electronics, control system and brake system are integrated into the wheel disk. This arrangement of the traction motor allows you to free up the space of the car for comfort and placement of the electric power storage. A combined excitation machine is proposed as an electric motor, the magnetic flux in which is created simultaneously by permanent magnets and an excitation winding. Permanent magnets allow you to increase the power in the limited dimensions of the disk, and the excitation winding allows you to adjust the magnetic flux, which significantly expands the range of speeds and torques of the vehicle. The design of the electric motor is innovative and protected by a patent of the Russian Federation. To develop a number of similar motor wheels, a design system has been proposed, which consists of two parts: synthesis and analysis. The synthesis system generates the optimal geometry of the electric motor for a specific technical task of the customer. It contains a multi-level structure that allows you to implement developments for various project situations with and without restrictions. The system contains seven such levels. Optimality criteria can be selected depending on the requirements of the project. The analysis system is based on the principle of a digital double. Its methodological basis is the finite element method. The system allows you to conduct a detailed analysis of the electromagnetic and thermal state, to obtain all the necessary integral characteristics. The performance of the design system has been tested on a digital analogue of a real racetrack, which is divided into sections with specified speed modes. The program outputs 15 parameters of both the car and the electric motor. In conclusion, the article shows the design study of a motor wheel for a racing electric car. The design of the prototype and the results of its tests are presented. The design system for the development of motor wheels based on a valve motor of combined excitation can be used for mass production.

Design and analysis of switched reluctance motor with FEM based Ansys-Maxwell

In this study, radial forces that create noise, which is a fundamental problem in Switched Reluctance Motor (SRM), are investigated. Since radial force causes stator vibrations and noise caused by magnetic field, a new switched reluctance motor model with increased stator and rotor poles has been designed in order to reduce the radial force acting on the rotor poles. In addition, a structure with high torque and low leakage flux compared to conventional winding structure has been proposed for Switched Reluctance Motors (SRM). The windings of the designed SRM are placed in layers, insulated from each other. Rotor poles are formed to move on both sides of each phase winding. Thus, the flux that will occur in the phase windings axially completes its circuit from the stator poles and the rotor poles. This designed ARM model has been examined by Finite Element Method (FEM. The proposed motor geometry has been analyzed with ANSYS Maxwell-3D, which performs FEM-based solution), and parametric analysis with ANSYS-RMxprt.

Magnetic Vibration in Induction Motor Caused by Supply Voltage Distortion

This article discusses magnetic vibrations in squirrel-cage induction motor stators and provides a mathematical description of the process of their excitation. A model of a 30 kW squirrel-cage induction motor was developed in finite element software. This model considers the motor geometry, material properties and stator winding. The electromagnetic and mechanical processes in the motor during the rotation of the rotor were considered. In the course of this study, currents of various harmonic compositions and amplitudes were applied to the motor windings, which caused magnetic noise, vibration and pulsations of the electromagnetic torque. Magnetic noises, vibrations and pulsations of the electromagnetic torque were investigated in the case of imbalance and harmonic distortions of the supply voltage.

Study the dynamic performance of PM machines for different rotor topologies

<p>For hybrid and electric vehicle drive-train (automotive applications) achieving high torque and efficiency at a wide range of operating conditions can be considered an important matter. Therefore, precise structure optimization of the permanent magnet synchronous machines (PMSMs) is recommended. Consequently, the effect of the main leading design parameters (such as PM arrangement, magnet thickness, pole arc to pole pitch ratio, airgap length as well as the effect of shaft material) for a different number of rotor poles configuration of PMSM can achieve optimum design results in electric motors with economical cost and excellent performance. This paper submits a comparative analysis of different rotor topologies of (PMSM). Moreover, the dynamic performances of the suggested rotor geometry topologies are investigated based on investigation of finite element analysis (FEA). The analysis offers a piece of complete information about the magnetic flux distribution and magnetic flux density over the motor geometry. Gained results from the analysis are used to give a decision for the selection of a suitable PMSM design.</p>

Deep-Investigated Analytical Modeling of a Surface Permanent Magnet Vernier Motor

Permanent magnet Vernier motors (PMVMs) possess the advantage of high torque density for high-performance applications. However, the low power factor challenge makes it unacceptable for direct-drive applications. A lack of accurate modeling method based on the motor sizing law, i.e., air-gap flux density, linear current density, and motor geometry parameters, raises difficulties for machine designers to further conduct research on the performance metrics. This article presents a deep investigation into the analytical modeling technique for surface PMVMs (SPMVMs). It can identify an accurate approach to obtain the performance metrics, including electromagnetic torque and power factor. The modeling technique is developed based on the conformal mapping method. By using this, both radial and tangential permeability functions can be calculated to obtain the motor magnetic loading accurately, considering the leakage flux. The slotting effect on both air-gap flux density and armature-winding function is analyzed to achieve a precise formula for torque and power factor computations. The new modeling technique is applied to integral-slot SPMVMs with different slot/pole combinations, gear ratios, slot openings, and magnet thickness to evaluate the impacts of motor parameters on high-power-factor and high-torque-density designs. Finally, an SPMVM with the characteristics of high torque density and power factor is fabricated to verify the analytical model at the power rating of 0.8 kW and the speed of 500 r/min. The experimental results show that the prototype exhibits a high power factor of 0.9 and high torque density 22.5 Nm/L.

Geometry influence of stator and rotor armatures on energy efficiency of induction motors

This paper presents the geometry influence of stator and rotor armatures on induction motor energy efficiency. The entire work is analyzed using a Motor-CAD programming environment. In principle, in the first stage, the influence of each armature is distinctly visualized upon loss level, for given effective power and given cooling algorithm through geometry changes that concern aspects related to the dimensions of the ferromagnetic core and the notches practiced within it. Afterwards, in a second stage, a synergistic modification of the induction motor geometry is carried out by cumulating the changes (cooperative effect) at the level of the two armatures, aiming to find the topology that provides – for some given effective power, and cooling algorithm – the highest energy efficiency.