Simulation System for Optimizing Urban Traffic Network Based on Multi-scale Fusion

Xiuhe Wang 보안공학연구지원센터 2014 International Journal of Smart Home Vol.8 No.2

Design Techniques for Reducing Cogging Torque in Permanent Magnet Flux Switching Machine

Daohan Wang,Xiuhe Wang,Sang-Yong Jung 한국자기학회 2013 Journal of Magnetics Vol.18 No.3

Permanent magnet flux switching motor (PMFSM) is a novel double salient machine which employs PMs instead of field winding for excitation. PMFSM contains only one set of armature winding, thereby features simple control strategy, low cost power inverter and substantial high efficiency. Due to the unique double salient structure and operation principle, the generated cogging torque in PMFSM is critical and quite different compared to the traditional PM machines. This paper presents and investigates various design techniques for reducing cogging torque in PMFSM. Firstly, an analytical model is proposed to study the influence of different methods on cogging torque. Then the optimal design parameters for minimizing cogging torque are determined by the analytical model, which significantly reduces the computational efforts. At last, the cogging torque with different design approaches are simulated by FEA along with the average output electromagnetic torque, which validates the analysis above.

Reduction on Cogging Torque in Flux-Switching Permanent Magnet Machine by Teeth Notching Schemes

Daohan Wang,Xiuhe Wang,Sang-Yong Jung IEEE 2012 IEEE transactions on magnetics Vol.48 No.11

<P>The cogging torque in flux-switching permanent magnet machines (FSPMs) is high due to its unique structure and high air-gap flux density. The cogging torque principle in FSPM is different from that in traditional PM machines, which can not be correctly predicted by analytical consideration. The aim of paper is to present the investigation on cogging torque principle in FSPM by analyzing the flux density distribution and a simple cogging torque reduction technique, i.e., teeth notching. Various kinds of notching schemes and their influence on cogging torque are examined along with instantaneous torque and average output torque at different load conditions. Numerical optimization process combined with finite-element analysis, which gives more preciseness to calculations, is performed to minimize cogging torque. The results show that the cogging torque circle depends on the real flux density distribution in the machine rather than the number of stator/rotor poles and the presented method can greatly reduce the torque ripple at only slight cost of average output torque.</P>

Analytical Performance Modelling of Slotted Surface-Mounted Permanent Magnet Machines with Rotor Eccentricity

Yan, Bo,Wang, Xiuhe,Yang, Yubo The Korean Institute of Electrical Engineers 2017 Journal of Electrical Engineering & Technology Vol.12 No.2

This paper presents an improved subdomain method to predict the magnet field distributions and electromagnetic performance of the surface-mounted permanent magnet (SPM) machines with static or dynamic eccentricity. Conventional subdomain models are either based on the scalar magnet potential to predict the rotor eccentricity effect or dependent on the magnetic vector potential without considering the eccentric rotor. In this paper, both the magnetic vector potential and the perturbation theory are introduced in order to accurately calculate the effect of rotor eccentricity on the open-circuit and armature reaction performance. The calculation results are presented and validated by the corresponding finite-element method (FEM) results.

Rotor Stress Analysis of High-Speed Surface-Mounted Permanent Magnet Motors with Segmented Poles Considering Fillings

Xing Zezhi,Wang Xiuhe,Zhao Wenliang 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.3

This paper presents an analytical method for calculating rotor stresses of high-speed surface-mounted permanent magnet synchronous motors (SPMSMs) with segmented permanent magnets (PMs), the pole-arc coefficient, fillings between poles, and material anisotropy are accurately considered. Afterward, the rotor stresses with different retaining sleeves and fillings are compared, the variation laws of rotor stresses with the materials of the retaining sleeve and filling are summarized, and the optimal filling material is determined. The maximum tangential stresses of the PMs and retaining sleeves of high-speed SPMSMs with segmented PMs can be effectively reduced by filling PPS between the segmented PMs or designing the rotor as a surface-inserted structure. The stress extreme conditions of the PMs and the retaining sleeves with different materials are different. Compared with the Inconel718 retaining sleeve, the thickness of the carbon fiber retaining sleeve is smaller.

Electromagnetic Vibration Reduction of Surface-Mounted Permanent Magnet Synchronous Motors Based on Eccentric Magnetic Poles

Xing Zezhi,Wang Xiuhe,Zhao Wenliang 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.5

As an important indicator to evaluate the performance of electric vehicles, the electromagnetic vibration of the motor is excited by the electromagnetic force waves acting on the stator core. Considering the influence of complex stator slot structure and inevitable saturation at teeth, the electromagnetic force waves of surface-mounted permanent magnet synchronous motor with eccentric magnetic poles are calculated quickly and accurately by combining the magnetomotive force-permeance method and the improved subdomain method, the amplitudes, orders, and frequencies of electromagnetic force waves are calculated and summarized. Considering the anisotropy of the stator material and the influence of the enclosure and windings, the natural frequencies of the entire stator are analyzed, and the vibration accelerations are calculated by the multiphysics model including electromagnetic, structural, and vibration models. Furthermore, the components of electromagnetic force waves that have a great impact on electromagnetic vibration are summarized, and the optimal parameters of eccentric magnetic poles that can effectively weaken the electromagnetic vibration are obtained by combining the particle swarm optimization algorithm and the subdomain method. For the 6-pole 36-slot motor, the maximum vibration accelerations of the motor are reduced by 45.14% at no load and 42.74% at rated load by optimizing the parameters of eccentric magnetic poles.

Design and Analysis of Basic Model of High-speed Surface-mounted Permanent Magnet Synchronous Motors Based on Subdomain Method

Xing Zezhi,Wang Xiuhe,Zhao Wenliang 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.5

This paper presents a design method of the basic model of high-speed surface-mounted permanent magnet synchronous motor (SPMSM) comprehensively considering the mechanical and electromagnetic properties based on the subdomain method. In the rotor design stage, the mechanical stresses of the permanent magnet (PM) and retaining sleeve are investigated and calculated by the subdomain method, the interference pre-stress, centrifugal force, thermal stress, and material anisotropy are accurately considered. For the rotors with different retaining sleeves, the rotor parameters such as the thicknesses of the PM and retaining sleeve and the interference between them considering both electromagnetic performance and stress extreme conditions are determined. In the stator design stage, the performances of motors with different stator structures are analyzed and compared based on the subdomain method considering stator saturation, and the optimal stator structure parameters are determined. Finally, the design scheme of the 2-pole 36-slot high-speed SPMSM that meets the requirements of mechanical and electromagnetic properties is determined, and the comprehensive performance of the motor is verified by the finite element method (FEM).

Analytical Performance Modelling of Slotted Surface-Mounted Permanent Magnet Machines with Rotor Eccentricity

Bo Yan,Xiuhe Wang,Yubo Yang 대한전기학회 2017 Journal of Electrical Engineering & Technology Vol.12 No.2

This paper presents an improved subdomain method to predict the magnet field distributions and electromagnetic performance of the surface-mounted permanent magnet (SPM) machines with static or dynamic eccentricity. Conventional subdomain models are either based on the scalar magnet potential to predict the rotor eccentricity effect or dependent on the magnetic vector potential without considering the eccentric rotor. In this paper, both the magnetic vector potential and the perturbation theory are introduced in order to accurately calculate the effect of rotor eccentricity on the open-circuit and armature reaction performance. The calculation results are presented and validated by the corresponding finite-element method (FEM) results.

Analysis and Reduction of Electromagnetic Force Waves of Permanent Magnet Synchronous Motors Considering Rotor Eccentricity

Xing Zezhi,Wang Xiuhe,Zhao Wenliang 대한전기학회 2021 Journal of Electrical Engineering & Technology Vol.16 No.6

The accurate calculation and reduction of electromagnetic force waves are important prerequisite for the evaluation and optimization of electromagnetic vibration. In this paper, an accurate calculation method of air gap permeance is proposed, the air gap fl ux density and the resulting electromagnetic force waves of 6p36s surface-mounted permanent magnet synchronous motor considering the rotor eccentricity are analyzed and calculated. Furthermore, the components of air gap fl ux density and electromagnetic force waves under rotor eccentricity with three diff erent windings connection modes at rated load are compared. The results indicate that the components of electromagnetic force waves introduced by rotor eccentricity can be eff ectively weakened by adopting appropriate windings connection modes without aff ecting the basic performance of the motor, and the windings connection mode in which the adjacent coils of each phase constitute parallel branches with equalizing lines has the best weakening eff ect.