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This paper proposes a novel flux switching claw pole machine (FSCPM) with soft magnetic composite (SMC) cores. The proposed FSCPM holds advantages of the conventional flux switching permanent magnet machine (FSPMM) and claw pole machine (CPM) with SMC cores. As permanent magnets are installed between the stator claw pole teeth, FSCPM has good flux concentrating ability, and the air gap flux density can be significantly improved. The torque coefficient of FSCPM is relatively high due to the applied claw pole teeth and global winding. FSCPM is mechanically robust because there are no windings or PMs on its rotor. Moreover, the core loss of FSCPM is relatively low for the SMC material has lower core loss at high frequency compared with silicon steels. The topology and operational principle of FSCPM are explained first. Several main dimensions of the machine are optimized to achieve better performance, based on 3D finite element method (FEM). Furthermore, the rotor skewing technology is adopted to reduce the cogging torque and torque ripple. [ABSTRACT FROM AUTHOR]

This paper proposes a novel permanent magnet assisted synchronous reluctance (PMAREL) machine, the main structure of this machine is quite similar to that of traditional PMAREL machine, and the main difference is that the grain-oriented silicon steel is used to replace some part of the stator teeth. The rolling direction of the grain-oriented silicon steel is along the radial direction of the machine, thus the advantage of higher permeability and higher kneel point in this material can be used to release the flux saturation problem of the traditional non-grain-oriented steel used in the PMAREL machine when the applied current density is high. Firstly, the structure of both proposed novel and traditional PMAREL machines are optimized and the design parameters are determined. Secondly the electromagnetic and mechanical performance are compared in these two machines which includes the demagnetization analysis, mechanical stress analysis when the rotor at the maximum speed, torque ability, efficiency by using the finite element method (FEM). It can be seen that the problem of stator teeth saturation in the novel PMAREL has been alleviated, and compared with the traditional PMAREL machine, the novel PMAREL has higher efficiency, wider speed range and 7% higher torque ability. [ABSTRACT FROM AUTHOR]

To improve output torque ability and reduce torque ripple in traditional synchronous reluctance motor (TSynRM), a new synchronous reluctance motor (NSynRM) is proposed in this paper. The rotor of NSynRM is composed of both grain-oriented silicon steel and non-oriented silicon steel. With the reasonable design of rotor structure, the torque of NSynRM has been improved and its torque ripple has been reduced greatly. Firstly, TSynRM and NSynRM are qualitatively compared by using the magnetic network method. Secondly, the main parameters of these two machines are optimized by using finite element method (FEM). Then the performance comparison between two optimized machines are carried out. Finally, the equivalent stress of these two machines at the maximum speed are analyzed. It can be seen that NSynRM can have 6.8% higher torque under rated load, 8% higher torque under maximum load, 17.5% wider constant torque operation region, and lower torque ripple compared with the TSynRM. [ABSTRACT FROM AUTHOR]

Cogging torque in permanent-magnet brushless DC (BLDC) motor causes torque and speed ripples, as well as acoustic noise and vibration, especially in low speed and direct drive applications. In this paper, the stator core shape is optimized by using a level set based topology optimization to reduce cogging torque. The level set method can represent the precise boundary shape of structure and also deal with complex topology changes during the optimization process. Different from the conventional rectangular meshes, the level set technique based triangular finite element meshes are presented in this paper to deal with irregular domains. The comparison of cogging torque calculated before and after topology optimization verifies the advantages of the level set topology optimization based on triangular meshes. [ABSTRACT FROM AUTHOR]

In this paper a comprehensive nonlinear model of surface mounted permanent magnet synchronous machine (SPMSM) is proposed considering both the structural and the saturation saliencies to enable the numerical simulation of new rotor position detection algorithms. An experiment platform is carried out to test and collect the incremental inductance values varying again the stator current levels and the rotor position. The Least Relative Residual Sum of Square (LRRSS) method is employed in the nonlinear inductance function regression. After experimentally identifying out all the parameters, a nonlinear mathematic model of SPMSM is built up. Furthermore, the direct torque control (DTC) scheme is applied to this new model to verify the model and simulate the machine performance. [ABSTRACT FROM AUTHOR]

This paper presents a hysteresis model for Type-II high temperature superconductor (HTS) by using simplified Preisach Model, in which the Preisach distribution function μ_kα, β) is determined only based on the B-H limiting loop. The nonlinear dynamic circuit model of the superconductor is established. In the circuit model, the hysteresis inductance and hysteresis loss described by using simplified Preisach Model are deduced. Applying the hysteresis circuit model, the currents flowing in different superconductor layers of high temperature superconducting cable are simulated, as well as the hysteresis loss of the superconducting cable. The simulation results are verified by comparison with the data recorded in literatures. Finally, the influences of hysteresis on superconducting cable are analyzed and discussed. [ABSTRACT FROM AUTHOR]

This paper presents a method based on Current Hoop Model for the analysis and design of induction coilgun. The cylindrically symmetric armature is subdivided into concentric hoops with diverse rectangular cross-sections, in each of which the current is assumed to be uniformly distributed. An equivalent analytical model considering mutual coupling of coils and armature hoops is constructed for dynamic simulation of the coilgun. Based on this model, the self- and mutual-inductances of exciting winding and hoops are calculated by Neumann method. The circuit equations are solved coupled with the equation of motion of projectile by using the Treanor method to ensure the convergence. Comparison between the experimental results and the numerical results simulated by Finite Element method (FEM) shows the validity of the presented simulation method for coilgun. The optimization of a six-stage coilgun is achieved by employing the genetic algorithm (GA). [ABSTRACT FROM AUTHOR]