Split ratio,i.e.the ratio of stator inner diameter to outer diameter,has a closed relationship with electromagnetic performance of permanent magnet(PM)motors.In this paper,the toroidal windings with short end-winding ...Split ratio,i.e.the ratio of stator inner diameter to outer diameter,has a closed relationship with electromagnetic performance of permanent magnet(PM)motors.In this paper,the toroidal windings with short end-winding axial length are employed in the 6-slot/2-pole(6s/2p)PM motor for high speed applications.The split ratio is optimized together with the ratio of inner slot to outer slot area,i.e.slot ratio,considering stator total loss(stator iron loss and copper loss).In addition,the influence of maximum stator iron flux density and tooth-tip on the optimal split ratio,slot ratio,and average torque is investigated.The analytical predictions show that when the slot ratio is 0.5,the maximum torque can be achieved,and the optimal split ratio increases with the decrease of slot ratio,as confirmed by the finite element(FE)analyses.Finally,some of predicted results are verified by the measured results of 6s/2p prototype motor with 0.5 slot ratio.展开更多
This paper presents the analytical design and high performance of step-constant tapered slot antenna (STSA) for ultra-wideband application. The return loss, radiation pattern, antenna gain, and level of cross polariza...This paper presents the analytical design and high performance of step-constant tapered slot antenna (STSA) for ultra-wideband application. The return loss, radiation pattern, antenna gain, and level of cross polarization of this antenna are presented and analyzed. Utilizing Rogers (RO3006) substrate having a relative permittivity of 6.15, the proposed antenna provides the ultra-wideband (UWB) from 3.1 GHz to 10.6 GHz. It is observed that the return loss and gain are increased with increasing the step size. It has been observed from the simulation results incorporating CST microwave studio commercial software version 2015, the optimum return loss, directivity and gain are ?43 dB, 10.52 dBi and 10.20 dB, respectively, for 15 step size. Therefore, the newly proposed antenna will be a decent candidate for ultra-wideband application.展开更多
文摘Split ratio,i.e.the ratio of stator inner diameter to outer diameter,has a closed relationship with electromagnetic performance of permanent magnet(PM)motors.In this paper,the toroidal windings with short end-winding axial length are employed in the 6-slot/2-pole(6s/2p)PM motor for high speed applications.The split ratio is optimized together with the ratio of inner slot to outer slot area,i.e.slot ratio,considering stator total loss(stator iron loss and copper loss).In addition,the influence of maximum stator iron flux density and tooth-tip on the optimal split ratio,slot ratio,and average torque is investigated.The analytical predictions show that when the slot ratio is 0.5,the maximum torque can be achieved,and the optimal split ratio increases with the decrease of slot ratio,as confirmed by the finite element(FE)analyses.Finally,some of predicted results are verified by the measured results of 6s/2p prototype motor with 0.5 slot ratio.
文摘This paper presents the analytical design and high performance of step-constant tapered slot antenna (STSA) for ultra-wideband application. The return loss, radiation pattern, antenna gain, and level of cross polarization of this antenna are presented and analyzed. Utilizing Rogers (RO3006) substrate having a relative permittivity of 6.15, the proposed antenna provides the ultra-wideband (UWB) from 3.1 GHz to 10.6 GHz. It is observed that the return loss and gain are increased with increasing the step size. It has been observed from the simulation results incorporating CST microwave studio commercial software version 2015, the optimum return loss, directivity and gain are ?43 dB, 10.52 dBi and 10.20 dB, respectively, for 15 step size. Therefore, the newly proposed antenna will be a decent candidate for ultra-wideband application.