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The aim of the work is to obtain practical results for the electrical machines multiparametric de-sign application, to conduct a comparative analysis of the parametric and multiparametric design results of a turbogenerator and its elements when the load changes; to confirm the prospects the multiparametric design application. Currently, it is possible to use mathematical models when designing, and use parametric synthesis to optimize one specific parameter, which in certain cas-es turns out to be sufficient. The peculiarity of electric machines calculation and design is the necessity of simultaneous checking of all interrelated parameters (mechanical, electromagnetic, thermal) with any changes. The structure design with simultaneous control of several variables cannot be performed using one stage of parametric design; additional calculations are necessary. In this case, multi-parameter design is necessary, but it requires longer preparation for design work and higher qualifications of personnel. Therefore, it is necessary to understand in which cases it is advisable to switch from parametric to multiparametric design. The work goal set is achieved by comparing the results of a turbogenerator, stator core and busbar designing using parametric and multiparametric design. The most important is to obtain the results of comparison of a complex electromechanical system parametric and multiparametric design (turbogenerator, its individual unit and element), including when the parameters of various physical processes change, performing a comparison of the obtained results, confirming the feasibility of carrying out multiparametric design. The significance of the obtained results is that practical examples of the multiparameter modeling use are shown. Using multiparametric design, not only a busbar refined form with increased repair and operational reliability was obtained, but the proposed so-lution economic advantages were also indicated.

In order to analyze the loss, temperature rise and the mechanical structural response under the combined magnetic tension and thermal stress of the stator core, the electromagnetic-temperature-stress coupling calculation for the stator core of a synchronous generator is carried out in this paper. Firstly, the core loss and the magnetic pull per unit area are theoretically deduced, followed by an analysis of the core's temperature rise characteristics. On this basis, the mechanical structure response of the core under the coupling excitation of magnetic pull and non-uniform thermal load is obtained. Then, a three-dimensional finite element model of the CS-5 synchronous generator is established. This model calculates the magnetic pull per unit area, loss curve and temperature distribution of the stator core. Furthermore, the deformation, strain and stress of the stator core under the simultaneous action of magnetic tension and thermal load are obtained. The results show that the stator slot temperature is highest when the generator runs stably. The deformation at the groove is largest and the stress at the bottom of the groove is higher. Finally, the temperature rises of the end face, inside slot and outside circle of the stator core are monitored in real-time by thermocouples and a temperature monitor. The measured temperature distribution of the stator core is in good agreement with the finite element simulation results, verifying the effectiveness of the electromagnetic-temperature-stress coupling method. In this paper, the temperature distribution of the stator core and the mechanical structural response distribution of the stator core under magnetic and thermal coupling excitation are obtained, providing a technical reference for the reverse optimization design of the generator structure and the prevention of stator core deformation.

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Amorphous alloys have attracted much attention in the field of high-speed motors because of their excellent comprehensive soft magnetic properties, especially their extremely low loss at high frequencies. In this paper, the advantages and types of amorphous motor are summarized, the key preparation processes of amorphous stator core are reviewed, and the advantages and disadvantages of radially laminated and axially wound core, modular splicing and integral forming core, slotted and slotless core are compared. The effects of the above-mentioned preparation processes on the properties of amorphous strip and iron core are summarized from the perspectives of annealing treatment, dipping curing and processing forming methods. Finally, combining with the latest research progress of amorphous motor, the problems existing in the application of amorphous alloy to the stator core of amorphous motor are analyzed, and the development of machining methods for amorphous motor stator core in the future is prospected. [ABSTRACT FROM AUTHOR]

Copyright of Large Electric Machine & Hydraulic Turbine is the property of Large Electric Machine & Hydraulic Turbine Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The advantages and features of the use of pressure accumulators (CA) with blocks of conic springs for restoring and stabilizing the pressing pressure of the stator core of a powerful turbogenerator (TG), which are installed under the tightening nuts or instead of them on the threaded ends of the tightening prisms of the core, are described. It is shown that the measurement of the displacement of the compression disc spring in the CA makes it possible to estimate the current state of the pressing pressure. The use of a capacitive sensor of linear displacements, placed outside the CA, to control the movement of the spring block in the caseless CA is substantiated. According to the specified design parameters of the caseless CA and the value of the maximum stroke of the plate springs in it, a capacitive sensor with its specified characteristics was developed. The method of monitoring the state of the TG stator core using the CA system with capacitive sensors on each CA and the control method with the alternate use of one disk spring travel meter are described. Ref. 14, fig. 6.

Copyright of Large Electric Machine & Hydraulic Turbine is the property of Large Electric Machine & Hydraulic Turbine Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Electrical machines play a major role in achieving a more sustainable economy by driving the further electrification of industry and transportation. To enhance the electric motor productivity during production and the efficiency during operation, it is essential to maximize the material yield rate during the production of stator and rotor sheet stacks and reduce iron losses during operation. Screen-printing technology can help to achieve these goals by producing thin magnetic sheet laminations in near-net-shape geometry, resulting in minimum material waste during production. Moreover, reducing the sheet thickness decreases the eddy current losses and avoids mechanical stress during manufacturing, leading to improved motor efficiency. Additionally, screen printing facilitates the production of multi-material components and variable alloy compositions. This study aims to identify the relevant factors and printing parameters so that screen-printed magnetic sheets can achieve product specifications. A method involving the statistical design of experiments is performed in several iterations to investigate the target parameters of the print cycle time, green part weight, shape integrity and layer thickness, and to analyze the main interdependencies. The results of this study provide valuable insights into optimizing the screen-printing process for soft magnetic sheets, enabling the production of efficient electric motors while reducing material scrap. [ABSTRACT FROM AUTHOR]

Copyright of Large Electric Machine & Hydraulic Turbine is the property of Large Electric Machine & Hydraulic Turbine Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The results of an analytical review of modern methods and means of restoring and stabilizing the pressing pressure of the stator core of a powerful turbogenerator (TG) during operation are presented. The advantages and features of the use of power accumulators (PA) with blocks of disk springs for pressure stabilization, which are installed under the tightening nuts or instead of them on the threaded ends of the tightening prisms, are described. A number of TG and PA parameters that must be known to calculate the mechanical characteristics of the conic springs unit are outlined. It is shown that the optimal method of assembling disc springs into blocks in CA is combined (series-parallel). Based on the specified design parameters, the dependence of the force created by the disc spring and the spring block on the spring thickness was obtained. The dependence of the force of the spring block on the displacement of the pressure plate of the stator core for different values of the spring thickness was determined. The method of calculating the strength of disc springs is given. Ref. 12, fig. 9.

Electromagnetic resonance in electric motors arises when the electromagnetic force frequency coincides with any of the motor's natural frequencies, causing excessive vibration and noise. To address this issue, it is crucial to design motors such that their natural frequencies do not closely align with the electromagnetic force frequency. However, vacuum cleaner motors operate across a broad range of speeds, generating a multitude of electromagnetic force frequencies, which makes it challenging to establish natural frequencies that can avoid all possible electromagnetic resonances. This article presents a novel approach for shifting natural frequencies by adjusting the stiffness of stator cores. By integrating an auxiliary component with various design factors into the motor, a range of natural frequencies can be achieved. An optimal natural frequency that mitigates electromagnetic resonance was identified among these modified frequencies, and the subsequent enhancement in acoustic characteristics was demonstrated.

Switched reluctance motor has the advantages of the high efficiency, low cost, strong fault tolerance, and high reliability. A 5.5 kW, 12/8 pole switched reluctance motor is designed. The novel transient electromagnetic field-control circuit coupled calculation method of switched reluctance motor is proposed. The influence of different PWM switching angles, chopping current thresholds, and hysteresis current widths on flux density and loss of stator core in the switched reluctance motor is studied in detailed by this novel method. Controller harmonics are considered during this calculation. The change of the flux density and loss of stator core in the switched reluctance motor is compared and analyzed under the different controller parameters. The reliability of the calculation method and accuracy of the calculation results are verified by experimental values.

Presented are the results of numerical studies of the distribution of vibration displacements and mechanical stresses in the insulation of the frontal part of the stator winding of a powerful turbogenerator under the influence of electrody-namics forces for different constructive solutions of the groove fastening of the winding rods in the end zone of the gen-erator stator core. Modeling of mechanical processes is carried out using the finite element numerical method (FEM) in a two-dimensional setting. The possibility of improving the design with the aim of reducing the amplitude of oscillations of the front parts of the stator winding was considered. Ref. 16, fig. 7.

Based on the finite element method, a numerical method for calculating thermomechanical movements and stresses of the components of the stator winding of a powerful turbogenerator is proposed, taking into account its regime and structural factors. The results of studies of these characteristics in insulation along the length of the core in radial and axial directions in different variants of fixing the winding in the end zone of the core are presented. The regularities of distribution of maximum and average values of thermomechanical parameters in the groove and frontal parts with the traditional method of fastening and the presence of a free section of the core in the end zone of the stator in the nominal mode of operation of the generator are determined. Ref. 12, fig. 4.

One of the attractive benefits of slotless machines is low losses at high speeds, which could be emphasized by a careful stator core loss assessment, potentially available already at the predesign stage. Unfortunately, mainstream iron loss estimation methods are typically implemented in the finite element analysis environment with a constant coefficients dummy model, leading to weak extrapolations with huge errors. In this article, an analytical method for the iron loss prediction in the stator core of slotless PM machines is derived. It is based on the extension of the 2-D field solution over the entire machine geometry. Then, the analytical solution is combined with variable coefficient loss models (VARCO) or constant coefficient loss models, which can be efficiently computed by vectorized postprocessing. VARCO loss models are shown to be preferred at a general level. Moreover, this article proposes a lookup-table-based solution as an alternative approach. The main contribution lies in the numerical link between the analytical field solution and the iron loss estimate, with the aid of a code implementation of the proposed methodology. First, the models are compared against a sufficiently dense dataset available from laminations manufacturer for validation purposes. Then, all the methods are compared for the slotless machine case. Finally, the models are applied to a real case study and validated experimentally. [ABSTRACT FROM AUTHOR]

The article is devoted to the development of an automatic method and device for monitoring the pressing of the stator core of a powerful turbo generator during its assembling at the manufacturer. The core is assembled and pressed in an upright position in separate parts; at each stage, it is necessary to monitor places with weakened solidity. The unevenness of the compaction density causes a relative displacement of the active steel sheets and losses of iron, as well as the appearance and development of certain defects (loosening of the teeth of the extreme packages, coloring of fragments of the active steel sheets, local closure of the sheets and heating of the packages), which can eventually cause severe accidents and failure of the turbo generator. Existing methods, including automatic ones, do not allow performing reliable monitoring. The method proposed by the authors for detecting places with weakened solidity is based on automatic measurement of the specific pressure of pressing during deformation of special control samples. A device for its implementation has been developed, which is a ring installed on the end surface of the core. Cells with control samples are evenly placed in the ring. The largest decrease in the sample thickness caused by the highest specific pressure corresponds to the smallest defect, and vice versa. As a pressure converter, it is proposed to use a flat metal membrane and a capacitive sensor with a digital output. The characteristics of the converter were calculated and experimentally verified. The specific pressure measurement results were processed using a special electronic unit. The device that has been developed makes it possible to improve labor productivity when monitoring the core, diagnose defects with greater reliability and eliminate them, and, ultimately, increase the reliability of the turbo generator as well as its durability.

With the help of mathematical simulation of mechanical processes in the stator core fastening system of a powerful turbogenerator end zone obtained appropriateness of basic parameters changes at the break of clamp prisms heads of the stator core. It is determined that the sudden break of one or more clamp prisms leads to longitudinal oscillation of their other working heads and stiff connected with them press plate, accordingly. Although such oscillation is insignificant but propagates along the entire surface of the press plate with a maximum value in the break zone and subsequent decrease with distance from this zone and therefore can be detected with the help of existing vibration sensors by installing them on the press plate. It is possible to use a limited number of sensors due to the propagation of vibration along the entire surface of the plate. But because the vibration changes are insignificant, in this case, there is a complexity of control that requires the use of high-sensitivity sensors and great informative computing equipment. According to the sensors indices, it is possible to determine the number of breaks for clamp prisms heads of the stator core and the number of them working heads, accordingly. Besides, this effect can be used to diagnose the un-compression of the stator core tooth zone. Since one of the important ways to improve the control and diagnostics of turbogenerators is the detection, the presence of such knowledge will allow making the optimal decision for further measures. Ref. 8, fig. 8, tables 2.

An accurate prediction of modal characteristics of motor stator is essential in order to design a low vibration motor and to operate it quietly. Scholars have done a lot of research on the modal analysis of stator core and winding. However, there are few papers for the 0th-order mode shape and frequency of the stator system. This paper aims to propose a new stator system analysis model, which can effectively analyze the 0th-order mode and improve the model calculation efficiency. Firstly, the modal of stator core and stator core-winding system were analyzed theoretically. Secondly, four stator system finite element analysis models were established. The modal analysis of the stator core and stator core-winding system were carried out using the four models. The validity and computational efficiency of the four models of the stator core and stator core-winding system were compared. A new stator system analysis model was proposed. Thirdly, the modal tests of the stator core and stator core-winding system were carried out by hammering method, and the validity of the finite element analysis model was verified. Compared with the traditional model, the newly proposed model can analyze the 0th-order mode more effectively and improve the computational efficiency.

A device for automated control by the stator core of a powerful turbine generator (TG) during assembly and pressing at the manufacturing plant is proposed. Using the device, places in the core with a weakened solidity are determined. For this, at N points evenly spaced along the cross section of the stator core, the specific pressing pressure of special plastic elements, which are installed in the control cells of the additional pressure ring of the press, on which the core is assembled, is measured. During pressing, the elements are deformed, and their deformation depends on the degree of core defect (decrease in solidity) in the zone of which they are located. The sample will be deformed less, located in the zone of the largest defect, and most of all - in the zone where the defect is minimal. The pressure is measured using a flat metal membrane with a rigid center on which strain gauges are located at selected points. It is shown that the relative deformations in a flat membrane, which are measured by strain gages, depend on the value of the specific pressing pressure. Analytical relationships between the relative radial and tangential deformations and the specific pressing pressure have been determined [ABSTRACT FROM AUTHOR]

Rotary variable differential transformer（RVDT）adopts non-contract design, has the advantages of high sensitivity, good linearity and compact structure, and is widely used in automatic control system in the aviation field. The air gap between stator and rotor is one of the important structural parameters to improve its performance and reliability. This paper studies the air gap between stator and rotor and develops an optimized design with a typical product. Through theoretical simulation analysis and physical experimental tests, the influence of the air gap on the linearity and gradient of RVDT, the two important static indicators, is studied. In this way, under a certain structure size, the influence of the air gap size on the RVDT output gradient and linearity and the reasonable selection range of the air gap are obtained. The proposed study can not only provide strong support for the selection of product structure design parameters, but also revise the actual product structure size during engineering realization to improve the product qualification rate. In addition, the relevant research methods and conclusions obtained can also be promoted and applied to the development of redundant RVDT, providing a reference for the rapid development of such products. [ABSTRACT FROM AUTHOR]

A quasi-three-dimensional field mathematical model of the electromagnetic field and heat transfer processes in end zone of a powerful turbogenerator has been developed. A model is the intermediate version between two-dimensional and three-dimensional solutions and is based on the numeral calculations in transversal and longitudinal sections of turbogenerator, interconnected by a complex of boundary conditions. On the first stage, a two-dimensional field model of the electromagnetic field in transversal section of central zone of a turbogenerator is considered. Then, taking into account the field distribution in central part, the magnetic field in longitudinal section is simulated. In response to the symmetry of the machine along axial and radial directions, the calculation area of end zone is considered as a half of the rotor section along its axis and the section of the stator core tooth in the tangential direction (circumferentially). Having taken the distribution of electromagnetic parameters obtained in the load mode of the machine as the initial data, the thermal losses in the elements and nodes of the end zone are determined. As a result of solving the joint problem of calculating the electromagnetic field and heat exchange processes, the distribution of heating has been obtained not only on the surface, but also inside the structural parts of the end zone. In particular, it has been found that the maximum temperature of 97.3 °C takes place in the tooth area of the end package of the stator core. This is explained by the combined effect of the main radial field, the axial leakage flux of the frontal portions of the stator and rotor windings, as well as by the “buckling” of a portion of the main flux out of the air gap. In addition, the pressure plate shielding effect is the cause of local field concentration in the toothed zone of the end package. The presented model makes it possible as early as at the design stage to evaluate the efficiency of design solutions for the formation of the end zone of the turbogenerator stator for different load modes of the machine, including the modes of consumption of reactive power.

Establishing an accurate stator system modal analysis model is of great significance for the vibration and noise analysis of the motor, scholars still have some controversy about how to set the material properties of the stator core and winding in modal analysis. First, the equivalent models of the stator core and winding was analyzed, the initial value of equivalent material parameters was determined. Second, the finite element models were used to analyze the influence of the equivalent material parameters on the natural frequency, a correction method of equivalent material parameters was proposed. Third, the modal of the stator core and the stator core with winding were tested by the moving force method. The finite element analysis results are consistent with the modal test results. Some influence laws of equivalent material parameters on natural frequency are obtained. The proposed correction method of equivalent material parameters helps to quickly determine the equivalent material properties of the stator core and windings. Setting the properties of the stator core and the winding material to the orthotropic materials can ensure the accuracy of the modal analysis.

Robot joint drive motors require high‐torque and power densities due to their limited space. Surface mounted permanent magnet (SPM) motors are appropriate for a robot joint drive due to their advantages of ease of construction, high productivity, and high controllability. To utilise the limited space effectively, a rotor overhang structure (OS) is frequently used in SPM motors due the performance enhancement and simple fabrication. However, the OS effects do not increase linearly but converge when it becomes longer. To deal with problem, a flux‐absorbing structure (FAS), which can effectively improve the performances even in case of a quite long OS by forming an effective flux path between the OS and stator can be used. However, the FAS results in different electromagnetic and thermal characteristics. In particular, there have been few studies on the thermal characteristics of the FAS, which can change motor performance considerably. Hence, a lumped parameter thermal network (LPTN) which can effectively consider the heat sources and heat transfer characteristics influenced by the use of FAS, is proposed. The feasibility of the FAS and the usefulness of the proposed LPTN was verified experimentally. The presented analyses and results here can be utilised in various high‐torque‐density application. [ABSTRACT FROM AUTHOR]

In order to make more effective use of space in the electric machine, a novel field modulated permanent magnet gear (FMPMG) machine is proposed. The key design aspect of the proposed FMPMG machine is adopting an inner rotor configuration and a specially designed stator core, with fixed modulator pieces, to improve the fabrication feasibility and rotation reliability. Harmonic analysis with detailed theoretical derivation is performed and reveals that the modulator pieces fixed to the stator can modulate the flux density distribution as well and realise a magnetic‐gearing effect. The major parameters are designed and modelled by the 2D finite element method (FEM). First, based on the simulation analyses of the radial flux density distribution in the 'pseudo' outer and inner air gap, the specially designed stator is verified to create a nested magnetic‐gearing effect together with the rotor PMs. The back electromagnetic force and electromagnetic torque waveform are further analysed, and the results indicate that the proposed FMPMG machine is more suitable for use as a sinusoidal excitation drive. Finally, a prototype is fabricated for experimentation to further verify the theoretical and FEM simulative validity of the proposed FMPMG machine. [ABSTRACT FROM AUTHOR]

This study proposes a modified structure of the E‐core permanent magnet (PM) assist switched reluctance motor by relocating the PM blades inside the stator core. For this purpose, the PMs are removed from the stator poles and placed slantwise inside the yoke. The proposed yoke‐PM assist structure is characterised with higher average torque and a lower torque ripple with respect to the conventional pole‐PM assist structure. An analytical approach based on the magnetic equivalent circuit is applied at the preliminary design stage to predict the performance of the motor. Based on the presented analytical modelling, the physical dimensions of the motor are optimised via a genetic algorithm to maximise the motor torque and the overall steady state performance. For further verifications, the finite‐element analysis simulation results are verified by the experimental tests on the motor prototype. [ABSTRACT FROM AUTHOR]

Aiming at the problem that poor vibration and noise performance of motor can be caused when amorphous alloy is used as motor core material, the electromagnetic noise and vibration characteristics of amorphous permanent magnet motor were studied. Amorphous alloy Metglas2605SAl was used as stator core of a permanent magnet motor, the amorphous and silicon steel motors electromagnetic field distribution , the size of the electromagnetic force, vibration velocity and vibration acceleration, vibration displacement deformation, the noise distribution around the motor and the spectrum analysis were calculated by the finite element method for electromagnetic-mechanical-fluid coupling. The results show that radial electromagnetic force is the main cause of electromagnetic vibration, the vibration deformation and noise level of amorphous motor are obviously higher than that of silicon steel motor, the noise level of amorphous motor is 5 dB higher than that of silicon steel motor. [ABSTRACT FROM AUTHOR]

To solve the problem of the orthotropic material parameters acquisition, a novel method for the acquisition of the equivalent material parameters considering the orthotropy of the stator core and the windings in a switched reluctance motor (SRM) is proposed. First, a theoretical analysis of the influences of the orthotropic material parameters on the vibration characteristics is implemented. Second, according to the finite element (FE) equivalent model and the modal parameters obtained by the modal test, the equivalent orthotropic material parameters of the stator core and the windings are captured, respectively. Finally, considering the complex connections among components, a FE model of a SRM is established and validated by the modal test. The results indicate that the vibration characteristics of the FE model of the stator core and the windings with the orthotropic features can be analysed by assigning the equivalent orthotropic material parameters; the elastic modulus Ex (Ey) and the shear modulus Gxy have effects on both the symmetric modal frequencies and the antisymmetric modal frequencies; the shear modulus Gxz (Gyz) only affects the antisymmetric modal frequencies; the elastic modulus Ez can neither change the symmetric modal frequencies nor the antisymmetric modal frequencies. [ABSTRACT FROM AUTHOR]

In this study, a reliability model for the assembly process of a stator can on the stator core in the AP1000 reactor coolant pump in a reduced scale is developed. Firstly, the tube hydroforming-based stator can assembly method is reviewed briefly. In order to extract the factors affecting the assembly results, a numerical assembly model and an assembly experiment rig are established. Assembly results are predicted by numerical analysis and validated by experiment. A reliability model with the proposed corrected-partial least squares regression-response surface method (C-PLSR-RSM)-based system reliability method is developed. The model is applied to analyze the assembly reliability of the stator can, and the effects of failure dependency on the estimation accuracy of reliability, as well as the relationships between the assembly reliabilities and different single evaluation index. The results indicate that the reliability model is able to efficiently analyze the implicit stator can assembly problem. Failure correlation brings a negative correlation relationship between the different assembly performance functions. [ABSTRACT FROM AUTHOR]

The air-gap electromagnetic force is not the unique excitation which excites magnetism and solid coupling vibration on stator system of asynchronous machine. Besides, there should be a ponderomotive force as an internal electromagnetic excitation in stator core. Therefore, the magnetism and solid coupling vibration equation with both of the forces was obtained for the electromagnetically excited vibration on stator system of electrical machine. Based on Maxwell equations and the electromagnetic constitutive relation, the expressions of the electromagnetic field and force were derived by solving the eddy equation and the boundary conditions. With numerical calculation, the influences of geometric parameters on the electromagnetic field and forces were analyzed. The electromagnetic excitations of magnetism and solid coupling vibration on stator system were improved by the analysis of ponderomotive force in the stator core. Furthermore, the conclusions provide a theoretical basis for the electromagnetic design of asynchronous machine. [ABSTRACT FROM AUTHOR]

Here, a new winding is proposed for 5‐X variable reluctance resolver. In the proposed winding method, all the stator teeth are devoted to the signal windings and a peripheral slot is added to the stator core including two excitation coils. The performance of the resolver is discussed using the proposed winding and all previous winding methods. It is shown the position error of the resolver is less than that of the previously proposed methods and it can offer much simpler manufacturing process and consequently lower cost. All the analyses are performed using three‐dimensional time stepping finite element method and finally, a prototype of the resolver is built and tested. The comparison between simulation and test results verifies the success of the proposed winding method. [ABSTRACT FROM AUTHOR]

Accurate calculation of the vibration mode and natural frequency of a motor stator is the basis for reducing motor noise and vibration. However, the stator core and winding material parameters are difficult to determine, posing issues which result in modal calculation bias. To address the problem of calibrating the stator material parameters, we developed a parameter correction method based on modal frequency. First, the stator system was simplified to build a stator system finite element model. Secondly, the relationship between modal frequency and material parameters was analyzed by finite element software, the relationship between modal frequency and material parameters was derived, and the anisotropic material parameter correction method was summarized. Finally, a modal experiment was carried out by the hammering method, and the simulation and experimental errors were within 3%, which verified the accuracy of the finite element model. The proposed correction method of anisotropic material can quickly determine the stator material parameters, and the stator core and winding anisotropic material can ensure the accuracy of the modal analysis.