The Experts below are selected from a list of 16854 Experts worldwide ranked by ideXlab platform
Chris Gerada - One of the best experts on this subject based on the ideXlab platform.
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simplified analytical machine sizing for surface mounted permanent Magnet machines
International Electric Machines and Drives Conference, 2019Co-Authors: Patrick Xie, Ramkuma Ramanatha, Gaurang Vakil, Chris GeradaAbstract:This paper proposes a simplified analytical machine sizing procedure for a three-phase surface mounted permanent Magnet synchronous machines appropriate for both system level analysis and preliminary machine design. For system-level analysis, the proposed method can generate candidate machine models, be used to check if proposed performance values for a machine in a system level design problem are feasible or be integrated into a system-level optimization considering power electronics, passives, and machine. In machine design, the advantage of an analytical process over FEA is its computational efficient nature, capable of quickly generating numerous candidate designs across a wide search-space. Selected designs can be further refined using more computational intensive methods such as FEA, CFD, and machine design software. Outputs of the sizing procedure include, mass, volume, efficiency, slot and rotor geometry, winding dimensions, stator resistance, stator inductance, Magnet Flux linkage, air gap width, Magnet thickness, and steady state thermal results. The sizing procedure is validated using 2D electroMagnetic solver FEMM, and machine design software Motor-CAD.
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The Influence of Winding Location in Flux-Switching Permanent-Magnet Machines
IEEE Transactions on Magnetics, 2019Co-Authors: Hengliang Zhang, Mingjin Hu, David Gerada, Chris GeradaAbstract:The main purpose of this paper is to investigate the influence of winding location on back electromotive force (EMF) and armature inductance in Flux-switching permanent-Magnet (FSPM) machines. To obtain an analytical solution, a double-stator-pitch model is built based on the equivalent Magnetic circuit method. Then, the open-circuit characteristics in FSPM machines with different winding layouts are analyzed by both the analytical model and finite-element-analysis method. The analysis reveals that winding inductance is easier influenced by the winding location than the permanent-Magnet Flux linkage and corresponding back EMF. Finally, the analytical and finite-element predictions are verified by experimental results.
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self commissioning of interior permanent Magnet synchronous motor drives with high frequency current injection
IEEE Transactions on Industry Applications, 2014Co-Authors: Shafiq Odhano, Paolo Giangrande, R Bojoi, Chris GeradaAbstract:In this paper, a simple and robust method for parameter estimation at rotor standstill is presented for interior permanent Magnet (IPM) synchronous machines. The estimated parameters are the stator resistance through dc test, the dq inductances using high-frequency injection, and the permanent Magnet Flux by means of a closed-loop speed control maintaining rotor stationary. The proposed method does not require either locking the rotor or additional/special power supplies. The validity of the suggested method has been verified by implementation on two IPM motor prototypes. Finally, the estimated parameters have been compared against results obtained through finite-element simulations and with machine Magnetic characterization, separately performed, to validate the method's effectiveness. Saturation and cross-saturation effects are taken care of through amplitude modulation and cross-axis current application, respectively.
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self commissioning of interior permanent Magnet synchronous motor drives with high frequency current injection
Energy Conversion Congress and Exposition, 2013Co-Authors: Shafiq Odhano, Paolo Giangrande, R Bojoi, Chris GeradaAbstract:The knowledge of electrical and mechanical parameters of high-performance electromechanical drive systems is of paramount importance for designing high-performance controllers and/or developing accurate simulation models. By high-performance control is meant least torque (position) ripple for torque (position) control. Machine parameters are typically load and temperature dependent. This makes their estimation a challenging task. In this paper, a simple and robust method for parameter estimation at rotor standstill is presented. The estimated parameters are stator resistance through dc test, dq inductances using high-frequency injection and permanent Magnet Flux by means of a closed-loop speed control maintaining rotor stationary. The proposed method does not require either locking the rotor or additional/special power supplies. The validity of the suggested method has been verified by implementation on Interior Permanent Magnet Synchronous Motors (IPMSMs). Finally, the estimated parameters have been compared against results obtained through finite element simulations and with machine Magnetic characterization, separately performed, to validate the method's effectiveness. Saturation and cross-saturation effects are taken care of through amplitude modulation and cross-axis current application, respectively.
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Design Considerations for a Fault-Tolerant Flux-Switching Permanent-Magnet Machine
IEEE Transactions on Industrial Electronics, 2011Co-Authors: Tsarafidy Raminosoa, Chris Gerada, Michael GaleaAbstract:In safety critical aerospace applications, fault-tolerant drives can help reach the necessary system reliability levels without replicating the entire drive system and thus minimizing the overall system weight. Machine selection and design for fault tolerance has to be considered at an early stage to ensure optimal performance at a system level. This paper looks at the fault-tolerant properties of permanent-Magnet Flux-switching machines (PMFSMs) and proposes a new configuration able to fulfill the fault-tolerant requirements. PMFSMs have the distinct property of having a robust rotor construction with the permanent Magnets embedded in the stator while having their operational characteristics similar to those of synchronous permanent-Magnet machines. While these machines have numerous inherent advantages for achieving a high power density, in their basic form, they are not tolerant to short-circuit winding failures. This paper will look at a novel stator structure able to achieve a 1-p.u. winding inductance and will subsequently look at design iterations to maximize the torque density.
Ming Cheng - One of the best experts on this subject based on the ideXlab platform.
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analysis of stator slots and rotor pole pairs combinations of rotor permanent Magnet Flux switching machines
IEEE Transactions on Industrial Electronics, 2020Co-Authors: Wei Hua, Zhe Chen, Ming ChengAbstract:This paper investigates the influence of stator slots and rotor pole pairs combinations on torque performances in rotor permanent Magnet Flux switching (RPM-FS) machines. Based on a Magnetomotive force (MMF) permeance model, the candidates of stator slots and rotor pole pairs combinations with higher torque capability can be determined by analyzing the PM-MMF and winding factor. Meanwhile, the candidates with a lower torque ripple can be obtained by referring to the cogging torque, which is related to the greatest common divisor of stator slots and rotor pole pairs. In addition, from the field modulation principle, the RPM-FS machines with the same fundamental Magnetic loadings and winding factors exhibit identical fundamental harmonic torque, but different modulation harmonic components. Finally, four candidates with attractive torque performance are chosen, and the characteristics are verified by finite-element analysis and experiments.
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analysis of the operation principle for rotor permanent Magnet Flux switching machines
IEEE Transactions on Industrial Electronics, 2018Co-Authors: Wei Hua, Peng Han, Ming ChengAbstract:This paper proposes a topology of special rotor-type permanent-Magnet (PM) machine named rotor-PM Flux-switching (RPM-FS) machine, which is evolved from stator-PM Flux-switching (SPM-FS) topology and exhibits high power density, wide-range speed regulation, and good overload capability. The operation principle of RPM-FS machines is investigated based on the field modulation theory. It can be found that the torque is mainly contributed by the dominant harmonics in rotor-PM field and armature reaction field with the same order and rotating speed, i.e., 10, 14, and 34 pole pairs. In addition, a comprehensive comparison of modulation principles between the RPM-FS and SPM-FS machines is conducted from three perspectives, namely PM field, armature reaction field, and torque production mechanism. It is found that the modulation principle not only reveals the similarities of operation principle between two PM-FS machines, but also provides guidance for the combination of stator slots and rotor poles. Further, the electroMagnetic torque produced by the dominant harmonics in two machines is verified by finite-element analysis and experiments.
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analysis and evaluation of novel rotor permanent Magnet Flux switching machine for ev and hev applications
Iet Electric Power Applications, 2017Co-Authors: Wei Hua, Gan Zhang, Zhe Chen, Ming ChengAbstract:To relieve the serious saturation in stator teeth of stator-permanent-Magnet Flux-switching (SPM-FS) machines due to the co-existence of Magnets and armature windings in stator, this study proposes and analyses a novel rotor-permanent Magnet Flux-switching (RPM-FS) brushless machine. Different from the conventional SPM-FS machines, the Magnets are removed from stator to rotor, and Magnetised in a unique direction, resulting in a significant alleviation of stator tooth saturation level for the RPM-FS machines. The concentrated armature windings are still wound around stator teeth with an even shorter end-part winding length due to the absence of Magnets. To evaluate the advantages and disadvantages of RPM-FS machines, a comprehensive comparison between a RPM-FS machine, a SPM-FS machine, and an interior permanent Magnet machine used in Toyota-Prius 2004 hybrid electric vehicle, is conducted and the electroMagnetic performances of three machines are investigated by finite element analysis. The predicted results indicate the proposed RPM-FS machine exhibits the largest power density, greatest torque capability, highest efficiency under rated operation, and improved Flux-weakening ability. Therefore, the RPM-FS machine is a promising candidate for EV and hybrid electric vehicles applications especially for direct driven systems where the superior overloaded performance is crucial.
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a novel rotor permanent Magnet Flux switching machine
International Conference on Ecological Vehicles and Renewable Energies, 2015Co-Authors: Wei Hua, Gan Zhang, Ming ChengAbstract:In this paper, a novel rotor-permanent Magnet Flux-switching (RPM-FS) brushless machine is proposed, in which the Magnets are removed from stator as in the conventional stator-PM Flux-switching (SPM-FS) machines to rotor with a unique Magnetization direction, and three-phase concentrated armature windings are remained in stator. In addition to the introduction of the topology and operation principle of the RFS-PM machines, the electroMagnetic performance of this kind of machine is investigated and optimized by conventional two dimensional (2-D) finite element methods (FEM). Furthermore, to evaluate the merits and demerits of RPMFS machines, a comprehensive comparison between a RPM-FS machine, a conventional SPM-FS machine and an interior permanent Magnet (IPM) machine used in the hybrid electric vehicle (HEV) named Prius 2004 is conducted, where the three machines have the same stator outer diameter, stack length and DC-link voltage. The predicted results indicate the proposed RPM-FS machine exhibit the largest torque capability, lowest torque ripple, and is especially suitable for EV and HEV applications.
Robert D Lorenz - One of the best experts on this subject based on the ideXlab platform.
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high frequency injection based stator Flux linkage and torque estimation for db dtfc implementation on ipmsms considering cross saturation effects
IEEE Transactions on Industry Applications, 2014Co-Authors: Robert D LorenzAbstract:Deadbeat-direct torque and Flux control (DB-DTFC) is a direct torque control method that provides the fastest possible torque control, low ripple, easily integrated dynamic loss minimization control, and one control law that uses the inherent volt-second source properties of power electronics to enable operation over all operating conditions, including voltage limits. DB-DTFC is a model-based discrete time controller that relies on precise machine parameter, Flux, and torque estimation to provide fast dynamic torque control. In this paper, a new method for high-frequency injection (HFI)-based self- and mutual incremental inductance estimation is proposed and evaluated in both simulations and experiments. In this new method, the estimated incremental inductances including cross-coupling inductance due to cross saturation are curve fitted offline and then used to calculate the apparent inductances. With the apparent inductances, the stator resistance and permanent-Magnet Flux linkage are estimated using recursive least squares method online. The stator Flux linkage observer using the identified machine parameters yields improved stator Flux linkage estimates that enable precise torque calculation. Experimental evaluation of the HFI-based Flux estimates on torque estimation and control accuracy is performed at an interior permanent-Magnet synchronous machine drive test bench with a torque transducer mounted.
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high frequency injection based stator Flux linkage and torque estimation for db dtfc implementation on ipmsms considering cross saturation effects
Energy Conversion Congress and Exposition, 2013Co-Authors: Robert D LorenzAbstract:Deadbeat-direct torque and Flux control (DB-DTFC) has demonstrated several technical advantages over classical hysteresis DTC and PI regulator based direct torque control (DTC) methods. These include fast torque control, low ripple, easily integrated dynamic loss minimization control, and one control law that uses the inherent Volt-sec. source properties of power electronics to enable operation over all operating conditions including voltage limits. DB-DTFC uses the fundamental machine model to form the inverse solution for Volt-sec selection at each switching period. Therefore, DB-DTFC is a model-based discrete time controller that relies on accurate machine parameter estimation to provide accurate dynamic torque control. In this paper, a new method for high frequency injection-based real-time self- and mutual inductance estimation is proposed and evaluated in both simulations and experiments. In this new method, the estimated inductances including cross-coupling inductance due to cross-saturation are then used to estimate the stator resistance and permanent Magnet Flux linkage. The stator Flux linkage observer using the identified machine parameters, yields improved stator Flux linkage estimates that enable precise torque calculation. Experimental evaluation of the HFI-based Flux estimates on torque estimation and control accuracy is performed at an IPMSM drive test bench with torque transducer mounted.
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suggested design space in a pmsm parameter plane for variable Flux machines
International Electric Machines and Drives Conference, 2013Co-Authors: Brent S Gagas, Takashi Fukushige, Natee Limsuwan, Kan Akatsu, Robert D LorenzAbstract:In this paper, design space for variable Flux (VF) machines is examined in a permanent Magnet synchronous machine (PMSM) parameter plane based on constant parameter, lossless power conversion properties, and estimated total loss distributions (i.e. copper and iron losses) while applying a d-axis current constraint based on an assumed deMagnetization characteristic. Medium-to-high speed, partial torque operation is typical for duty cycle loads, such as in the case of the electric vehicle. VF machines can reduce losses in these operating conditions by reducing the internal Magnetization state of the Magnet, thereby reducing Flux linkage associated with Flux produced by the Magnet. In this paper, VF machines with large normalized permanent Magnet Flux linkage which are in the highly salient, Flux intensified (FI) machine design space (VFI-IPMs) are shown to have large maximum torque, rated power, inverter utilization, and constant power speed ratio (CPSR) as well as low losses in the low torque region over a wide speed range when compared to conventional fixed Magnet Flux PMSMs.
Wei Hua - One of the best experts on this subject based on the ideXlab platform.
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analysis of stator slots and rotor pole pairs combinations of rotor permanent Magnet Flux switching machines
IEEE Transactions on Industrial Electronics, 2020Co-Authors: Wei Hua, Zhe Chen, Ming ChengAbstract:This paper investigates the influence of stator slots and rotor pole pairs combinations on torque performances in rotor permanent Magnet Flux switching (RPM-FS) machines. Based on a Magnetomotive force (MMF) permeance model, the candidates of stator slots and rotor pole pairs combinations with higher torque capability can be determined by analyzing the PM-MMF and winding factor. Meanwhile, the candidates with a lower torque ripple can be obtained by referring to the cogging torque, which is related to the greatest common divisor of stator slots and rotor pole pairs. In addition, from the field modulation principle, the RPM-FS machines with the same fundamental Magnetic loadings and winding factors exhibit identical fundamental harmonic torque, but different modulation harmonic components. Finally, four candidates with attractive torque performance are chosen, and the characteristics are verified by finite-element analysis and experiments.
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analysis of the operation principle for rotor permanent Magnet Flux switching machines
IEEE Transactions on Industrial Electronics, 2018Co-Authors: Wei Hua, Peng Han, Ming ChengAbstract:This paper proposes a topology of special rotor-type permanent-Magnet (PM) machine named rotor-PM Flux-switching (RPM-FS) machine, which is evolved from stator-PM Flux-switching (SPM-FS) topology and exhibits high power density, wide-range speed regulation, and good overload capability. The operation principle of RPM-FS machines is investigated based on the field modulation theory. It can be found that the torque is mainly contributed by the dominant harmonics in rotor-PM field and armature reaction field with the same order and rotating speed, i.e., 10, 14, and 34 pole pairs. In addition, a comprehensive comparison of modulation principles between the RPM-FS and SPM-FS machines is conducted from three perspectives, namely PM field, armature reaction field, and torque production mechanism. It is found that the modulation principle not only reveals the similarities of operation principle between two PM-FS machines, but also provides guidance for the combination of stator slots and rotor poles. Further, the electroMagnetic torque produced by the dominant harmonics in two machines is verified by finite-element analysis and experiments.
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analysis and evaluation of novel rotor permanent Magnet Flux switching machine for ev and hev applications
Iet Electric Power Applications, 2017Co-Authors: Wei Hua, Gan Zhang, Zhe Chen, Ming ChengAbstract:To relieve the serious saturation in stator teeth of stator-permanent-Magnet Flux-switching (SPM-FS) machines due to the co-existence of Magnets and armature windings in stator, this study proposes and analyses a novel rotor-permanent Magnet Flux-switching (RPM-FS) brushless machine. Different from the conventional SPM-FS machines, the Magnets are removed from stator to rotor, and Magnetised in a unique direction, resulting in a significant alleviation of stator tooth saturation level for the RPM-FS machines. The concentrated armature windings are still wound around stator teeth with an even shorter end-part winding length due to the absence of Magnets. To evaluate the advantages and disadvantages of RPM-FS machines, a comprehensive comparison between a RPM-FS machine, a SPM-FS machine, and an interior permanent Magnet machine used in Toyota-Prius 2004 hybrid electric vehicle, is conducted and the electroMagnetic performances of three machines are investigated by finite element analysis. The predicted results indicate the proposed RPM-FS machine exhibits the largest power density, greatest torque capability, highest efficiency under rated operation, and improved Flux-weakening ability. Therefore, the RPM-FS machine is a promising candidate for EV and hybrid electric vehicles applications especially for direct driven systems where the superior overloaded performance is crucial.
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a novel rotor permanent Magnet Flux switching machine
International Conference on Ecological Vehicles and Renewable Energies, 2015Co-Authors: Wei Hua, Gan Zhang, Ming ChengAbstract:In this paper, a novel rotor-permanent Magnet Flux-switching (RPM-FS) brushless machine is proposed, in which the Magnets are removed from stator as in the conventional stator-PM Flux-switching (SPM-FS) machines to rotor with a unique Magnetization direction, and three-phase concentrated armature windings are remained in stator. In addition to the introduction of the topology and operation principle of the RFS-PM machines, the electroMagnetic performance of this kind of machine is investigated and optimized by conventional two dimensional (2-D) finite element methods (FEM). Furthermore, to evaluate the merits and demerits of RPMFS machines, a comprehensive comparison between a RPM-FS machine, a conventional SPM-FS machine and an interior permanent Magnet (IPM) machine used in the hybrid electric vehicle (HEV) named Prius 2004 is conducted, where the three machines have the same stator outer diameter, stack length and DC-link voltage. The predicted results indicate the proposed RPM-FS machine exhibit the largest torque capability, lowest torque ripple, and is especially suitable for EV and HEV applications.
Jian-xin Shen - One of the best experts on this subject based on the ideXlab platform.
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Investigation of Torque Characteristics in a Novel Permanent Magnet Flux Switching Machine With an Outer-Rotor Configuration
IEEE Transactions on Magnetics, 2014Co-Authors: Weizhong Fei, Patrick Chi-kwong Luk, Dong-min Miao, Jian-xin ShenAbstract:This paper comprehensively investigates the torque characteristics of a novel permanent Magnet Flux switching (PMFS) machine with outer-rotor configuration. Due to the nature of severe Magnetic saturations in the machine, it is of particular interest to ascertain the extent of impact of the load conditions on the overall torque output as well as its component parts. The frozen permeability techniques are implemented in finite element analysis (FEA) to segregate the output torque of the outer-rotor PMFS machine into three parts: cogging torque, reluctance torque, and permanent Magnet torque. 2-D FEA is first employed to reveal the effects of phase current amplitudes and angles on those three torque components as well as the overall torque, while the 3-D FEA is carried out to further uncover the influences of end effects on the torque characteristics of the machine. Finally, experimental tests on a prototype machine are performed to validate the torque characteristic predictions by FEA.
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a novel permanent Magnet Flux switching machine with an outer rotor configuration for in wheel light traction applications
IEEE Transactions on Industry Applications, 2012Co-Authors: Weizhong Fei, Jian-xin Shen, Yu Wang, P C K Luk, Meng Jia JinAbstract:This paper proposes a novel permanent-Magnet (PM) Flux switching (PMFS) machine with an outer-rotor configuration for in-wheel light traction applications. The geometric topology of the outer-rotor PMFS machine is introduced, and the analytical sizing equations are derived to determine the main design parameters of the machine. Two-dimensional finite-element analysis (FEA) models are developed to investigate and optimize the machine performance. Furthermore, the Flux-weakening capability of the machine is analyzed and further improved by segmental PMs with iron bridges. The machine performance predictions by 2-D FEA models are validated by experimental tests on the prototype machine. The suitability of the proposed outer-rotor PMFS machine for in-wheel light traction application is demonstrated.
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torque analysis of permanent Magnet Flux switching machines with rotor step skewing
IEEE Transactions on Magnetics, 2012Co-Authors: Weizhong Fei, P C K Luk, Jian-xin ShenAbstract:This paper investigates the torque characteristics of permanent-Magnet Flux switching (PMFS) machines with rotor step skewing. The cogging torque, torque ripple, and average output torque of a PMFS machine with a common stator and different rotor pole widths and rotor pole numbers are first established using two-dimensional (2-D) finite element analysis (FEA). A cost-effective rotor step skewing technique is then proposed to reduce the cogging torque and torque ripple of the machine with two different rotors. The results have revealed that the least step number and angle for optimal torque ripple mitigation of the PMFS machine are determined by the harmonic contents of the torque pulsation and the rotor pole number. The influences of load conditions on the machine torque characteristics are carried out by varying current excitations. The corresponding three-dimensional (3-D) FEA models are constructed and experimental prototypes are built for validations.
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permanent Magnet Flux switching integrated starter generator with different rotor configurations for cogging torque and torque ripple mitigations
IEEE Transactions on Industry Applications, 2011Co-Authors: Weizhong Fei, P C K Luk, Jian-xin Shen, Bin Xia, Yu WangAbstract:This paper investigates the cogging torque and torque ripple features of a permanent-Magnet Flux-switching integrated starter generator. The effects of the rotor pole arc width on the cogging torque, torque ripple, and output torque are first established using finite-element analysis (FEA). Three torque ripple reduction techniques based on the optimization of three different rotor pole configurations, namely, uniform, step skewed, and axial pairing, are then proposed. The torque characteristics of each rotor configuration at varying load currents and phase angles are studied in detail. A prototype machine with a common stator and the three optimized rotor configurations are built for experimental validation. Both the FEA results and the experimental tests show that the step skewed and axial pairing techniques can alleviate the cogging torque significantly, but the latter is less effective than the former in reducing the overall torque ripple.
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cogging torque suppression in a permanentMagnet Flux switching integrated starter generator
Iet Electric Power Applications, 2010Co-Authors: Meng Jia Jin, Jian-xin Shen, Y Wang, P C K Luk, Weizhong Fei, Cf WangAbstract:Permanent-Magnet Flux-switching (PMFS) machine offers high torque density, impressive Flux-weakening capability and mechanical ruggedness because of its distinctive configuration, and is potentially suitable for the application in automotive integrated-starter-generators (ISGs). However, the PMFS machine generally exhibits higher cogging torque compared with other machines commonly used in ISGs. Minimisation of the cogging torque in the PMFS machine for its utility in ISGs is therefore of particular importance. Four rotor topologies are proposed here as cost-effective means to suppress the cogging torque of a PMFS ISG. The validity of the proposed techniques has been confirmed by both two-dimensional finite-element analysis and experimental results. Moreover, the influence on the back electroMagnetic force by these techniques is also investigated.
