The Experts below are selected from a list of 4452 Experts worldwide ranked by ideXlab platform
T A Lipo - One of the best experts on this subject based on the ideXlab platform.
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torque quality and comparison of internal and external rotor axial flux surface magnet disc machines
IEEE Transactions on Industrial Electronics, 2006Co-Authors: Mensure Aydin, Surong Huang, T A LipoAbstract:In this paper, pulsating torque components of permanent magnet machines and pulsating torque minimization techniques are discussed for axial flux surface-magnet disc-type PM machines. The pulsating torque analysis describing general instantaneous electromagnetic torque equation and torque Ripple Factor is briefly provided in order to analyze torque Ripple component. Detailed finite-element analyses focusing on the minimization of cogging and torque Ripple components using several techniques are also given. A detailed comparison of the two techniques is also illustrated in this paper.
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torque quality and comparison of internal and external rotor axial flux surface magnet disc machines
Conference of the Industrial Electronics Society, 2001Co-Authors: Mensure Aydin, Surong Huang, T A LipoAbstract:In this paper, pulsating torque components of PM machines and pulsating torque minimization techniques are discussed for axial flux surface magnet disc type PM machines. The pulsating torque analysis describing general instantaneous electromagnetic torque equation and torque Ripple Factor (TRF) is briefly given in order to analyze Ripple torque of the machines. A detailed finite element analysis (FEA) focusing on the minimization of cogging and Ripple torque components using some techniques are also provided. A detailed comparison of the two techniques is also illustrated in the paper.
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torque quality assessment and sizing optimization for surface mounted permanent magnet machines
IEEE Industry Applications Society Annual Meeting, 2001Co-Authors: Surong Huang, Mensure Aydin, T A LipoAbstract:Torque quality assessment and optimization methods are presented in this paper. General purpose sizing equations are obtained and sizing optimization of the slotless TORUS machine is shown for maximum power density or efficiency points. For pulsating torque analysis, general instantaneous electromagnetic torque equation and torque Ripple Factor (TRF) analysis are carried out. Besides, stator winding distribution Factor and rotor PM skew Factor, excitation field form Factor to indicate the excitation field harmonics, open slot Factor to indicate the slot effect based on the calculation of airgap permeance are introduced for nonslotted and slotted axial flux surface mounted PM machines. Based on the above analysis, optimum design can be achieved for minimum Ripple torque. On the other hand, cogging torque can be canceled using nonslotted structure. A slotless TORUS machine is used as a sample application for the torque Ripple minimization in the paper. Furthermore, 2D and 3D finite element analysis (FEA) of both nonslotted and slotted surface mounted PM TORUS type (axial flux external rotor internal stator) structure, AFIR type (axial flux internal rotor external stator) structure and RFSM (radial flux internal rotor external stator) type structures are investigated for an insight into pulsating torques, Ripple torques and cogging torques. The results obtained from both TRF analysis and 2D/3D FEA are illustrated in the paper.
Nicu Bizon - One of the best experts on this subject based on the ideXlab platform.
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nonlinear control of fuel cell hybrid power sources part i voltage control
Applied Energy, 2011Co-Authors: Nicu BizonAbstract:In this paper is proposed a nonlinear control for fuel cell/battery/ultracapacitor hybrid power sources (HPS) that improves the performance and durability of fuel cell. The nonlinear voltage control is analyzed and designed using a systematic approach. The design goal is to stabilize the HPS output voltage at a low voltage Ripple that is also spread in a large frequencies band. All the results have been validated in several simulations. The simulation results successfully show that nonlinear voltage control performs good performances in the frequency-domain (a high spreading level of power spectrum) and in the time domain (a low level of output voltage Ripple Factor), too.
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a new topology of fuel cell hybrid power source for efficient operation and high reliability
Journal of Power Sources, 2011Co-Authors: Nicu BizonAbstract:Abstract This paper analyzes a new fuel cell Hybrid Power Source (HPS) topology having the feature to mitigate the current Ripple of the fuel cell inverter system. In the operation of the inverter system that is grid connected or supplies AC motors in vehicle application, the current Ripple normally appears at the DC port of the fuel cell HPS. Consequently, if mitigation measures are not applied, this Ripple is back propagated to the fuel cell stack. Other features of the proposed fuel cell HPS are the Maximum Power Point (MPP) tracking, high reliability in operation under sharp power pulses and improved energy efficiency in high power applications. This topology uses an inverter system directly powered from the appropriate fuel cell stack and a controlled buck current source as low power source used for Ripple mitigation. The low frequency Ripple mitigation is based on active control. The anti-Ripple current is injected in HPS output node and this has the LF power spectrum almost the same with the inverter Ripple. Consequently, the fuel cell current Ripple is mitigated by the designed active control. The Ripple mitigation performances are evaluated by indicators that are defined to measure the mitigation ratio of the low frequency harmonics. In this paper it is shown that good performances are obtained by using the hysteretic current control, but better if a dedicated nonlinear controller is used. Two ways to design the nonlinear control law are proposed. First is based on simulation trials that help to draw the characteristic of Ripple mitigation ratio vs. fuel cell current Ripple. The second is based on Fuzzy Logic Controller (FLC). The Ripple Factor is up to 1% in both cases.
Mensure Aydin - One of the best experts on this subject based on the ideXlab platform.
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torque quality and comparison of internal and external rotor axial flux surface magnet disc machines
IEEE Transactions on Industrial Electronics, 2006Co-Authors: Mensure Aydin, Surong Huang, T A LipoAbstract:In this paper, pulsating torque components of permanent magnet machines and pulsating torque minimization techniques are discussed for axial flux surface-magnet disc-type PM machines. The pulsating torque analysis describing general instantaneous electromagnetic torque equation and torque Ripple Factor is briefly provided in order to analyze torque Ripple component. Detailed finite-element analyses focusing on the minimization of cogging and torque Ripple components using several techniques are also given. A detailed comparison of the two techniques is also illustrated in this paper.
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torque quality and comparison of internal and external rotor axial flux surface magnet disc machines
Conference of the Industrial Electronics Society, 2001Co-Authors: Mensure Aydin, Surong Huang, T A LipoAbstract:In this paper, pulsating torque components of PM machines and pulsating torque minimization techniques are discussed for axial flux surface magnet disc type PM machines. The pulsating torque analysis describing general instantaneous electromagnetic torque equation and torque Ripple Factor (TRF) is briefly given in order to analyze Ripple torque of the machines. A detailed finite element analysis (FEA) focusing on the minimization of cogging and Ripple torque components using some techniques are also provided. A detailed comparison of the two techniques is also illustrated in the paper.
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torque quality assessment and sizing optimization for surface mounted permanent magnet machines
IEEE Industry Applications Society Annual Meeting, 2001Co-Authors: Surong Huang, Mensure Aydin, T A LipoAbstract:Torque quality assessment and optimization methods are presented in this paper. General purpose sizing equations are obtained and sizing optimization of the slotless TORUS machine is shown for maximum power density or efficiency points. For pulsating torque analysis, general instantaneous electromagnetic torque equation and torque Ripple Factor (TRF) analysis are carried out. Besides, stator winding distribution Factor and rotor PM skew Factor, excitation field form Factor to indicate the excitation field harmonics, open slot Factor to indicate the slot effect based on the calculation of airgap permeance are introduced for nonslotted and slotted axial flux surface mounted PM machines. Based on the above analysis, optimum design can be achieved for minimum Ripple torque. On the other hand, cogging torque can be canceled using nonslotted structure. A slotless TORUS machine is used as a sample application for the torque Ripple minimization in the paper. Furthermore, 2D and 3D finite element analysis (FEA) of both nonslotted and slotted surface mounted PM TORUS type (axial flux external rotor internal stator) structure, AFIR type (axial flux internal rotor external stator) structure and RFSM (radial flux internal rotor external stator) type structures are investigated for an insight into pulsating torques, Ripple torques and cogging torques. The results obtained from both TRF analysis and 2D/3D FEA are illustrated in the paper.
Yi Tang - One of the best experts on this subject based on the ideXlab platform.
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pulse density modulation for maximum efficiency point tracking of wireless power transfer systems
IEEE Transactions on Power Electronics, 2018Co-Authors: Hongchang Li, Jingyang Fang, Shuxin Chen, Kangping Wang, Yi TangAbstract:Maximum efficiency point tracking (MEPT) control has been adopted in state-of-the-art wireless power transfer (WPT) systems to meet the power demands with the highest efficiency against coupling and load variations. Conventional MEPT implementations use dc/dc converters on both transmitting and receiving sides to regulate the output voltage and maximize the system efficiency at the expense of increased overall complexity and power losses on the dc/dc converters. Other implementations use phase-shift control or on–off control of the transmitting side inverter and the receiving side active rectifier instead of dc/dc converters but cause new problems, e.g., hard switching, low average efficiency, and large dc voltage Ripples. This paper proposes a pulse density modulation (PDM) based implementation for MEPT to eliminate all the mentioned disadvantages of existing implementations. Delta-sigma modulators are used as an example to realize the PDM. A dual-side soft switching technique is proposed for the PDM. The Ripple Factor of the output voltage with PDM is derived. A 50 W WPT system is built to validate the proposed method. The system efficiency is maintained higher than 70% for various load resistances when the power transfer distance is 0.5 m, which is 1.67 times the diameter of the coils.
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pulse density modulation for maximum efficiency point tracking of wireless power transfer systems
IEEE Transactions on Power Electronics, 2018Co-Authors: Jingyang Fang, Shuxin Chen, Kangping Wang, Yi TangAbstract:Maximum efficiency point tracking (MEPT) control has been adopted in state-of-the-art wireless power transfer (WPT) systems to meet the power demands with the highest efficiency against coupling and load variations. Conventional MEPT implementations use dc/dc converters on both transmitting and receiving sides to regulate the output voltage and maximize the system efficiency at the expense of increased overall complexity and power losses on the dc/dc converters. Other implementations use phase-shift control or on–off control of the transmitting side inverter and the receiving side active rectifier instead of dc/dc converters but cause new problems, e.g., hard switching, low average efficiency, and large dc voltage Ripples. This paper proposes a pulse density modulation (PDM) based implementation for MEPT to eliminate all the mentioned disadvantages of existing implementations. Delta-sigma modulators are used as an example to realize the PDM. A dual-side soft switching technique is proposed for the PDM. The Ripple Factor of the output voltage with PDM is derived. A 50 W WPT system is built to validate the proposed method. The system efficiency is maintained higher than 70% for various load resistances when the power transfer distance is 0.5 m, which is 1.67 times the diameter of the coils.
Surong Huang - One of the best experts on this subject based on the ideXlab platform.
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torque quality and comparison of internal and external rotor axial flux surface magnet disc machines
IEEE Transactions on Industrial Electronics, 2006Co-Authors: Mensure Aydin, Surong Huang, T A LipoAbstract:In this paper, pulsating torque components of permanent magnet machines and pulsating torque minimization techniques are discussed for axial flux surface-magnet disc-type PM machines. The pulsating torque analysis describing general instantaneous electromagnetic torque equation and torque Ripple Factor is briefly provided in order to analyze torque Ripple component. Detailed finite-element analyses focusing on the minimization of cogging and torque Ripple components using several techniques are also given. A detailed comparison of the two techniques is also illustrated in this paper.
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torque quality and comparison of internal and external rotor axial flux surface magnet disc machines
Conference of the Industrial Electronics Society, 2001Co-Authors: Mensure Aydin, Surong Huang, T A LipoAbstract:In this paper, pulsating torque components of PM machines and pulsating torque minimization techniques are discussed for axial flux surface magnet disc type PM machines. The pulsating torque analysis describing general instantaneous electromagnetic torque equation and torque Ripple Factor (TRF) is briefly given in order to analyze Ripple torque of the machines. A detailed finite element analysis (FEA) focusing on the minimization of cogging and Ripple torque components using some techniques are also provided. A detailed comparison of the two techniques is also illustrated in the paper.
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torque quality assessment and sizing optimization for surface mounted permanent magnet machines
IEEE Industry Applications Society Annual Meeting, 2001Co-Authors: Surong Huang, Mensure Aydin, T A LipoAbstract:Torque quality assessment and optimization methods are presented in this paper. General purpose sizing equations are obtained and sizing optimization of the slotless TORUS machine is shown for maximum power density or efficiency points. For pulsating torque analysis, general instantaneous electromagnetic torque equation and torque Ripple Factor (TRF) analysis are carried out. Besides, stator winding distribution Factor and rotor PM skew Factor, excitation field form Factor to indicate the excitation field harmonics, open slot Factor to indicate the slot effect based on the calculation of airgap permeance are introduced for nonslotted and slotted axial flux surface mounted PM machines. Based on the above analysis, optimum design can be achieved for minimum Ripple torque. On the other hand, cogging torque can be canceled using nonslotted structure. A slotless TORUS machine is used as a sample application for the torque Ripple minimization in the paper. Furthermore, 2D and 3D finite element analysis (FEA) of both nonslotted and slotted surface mounted PM TORUS type (axial flux external rotor internal stator) structure, AFIR type (axial flux internal rotor external stator) structure and RFSM (radial flux internal rotor external stator) type structures are investigated for an insight into pulsating torques, Ripple torques and cogging torques. The results obtained from both TRF analysis and 2D/3D FEA are illustrated in the paper.
