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A quasi-three-dimensional (3-D) analytic method is presented for calculating the performance of single-sided linear induction motor with the ladder secondary. To simplify the analytic model, the ladder aluminum plate is equivalent to the flat-solid one, and the equivalent conductivity is derived and given. In the direction of the motion, the finite primary length and end effect are considered by the method of the Fourier transform and Residue theorem. In the transverse direction, considering finite width of the primary core and the region between the overhang of the primary windings and the secondary, the equivalent integral length is given. Finally, the thrust, vertical force and secondary efficiency are calculated and compared with the results of the 3-D finite-element method and experiment, it is shown that the method presented in the paper is much simpler and the accuracy of the analytic method is verified. [ABSTRACT FROM AUTHOR]

In this article, an electrodynamic suspension (EDS) maglev scheme with a novel coil topology named traveling magnetic electromagnetic Halbach array (TMEHA) is proposed and investigated in which thrust and lift forces are simultaneously created above a conductive flat guideway. First, the topological structure and principle of the TMEHA-EDS is introduced. Then the effectiveness of the TMEHA is analyzed qualitatively according to the analytic model based on harmonic analytical theory. Third, the 2-D analytical model of the TMEHA-EDS is proposed, and the thrust, lift force, efficiency, and the lift-to-weight ratio of the TMEHA-EDS are analyzed. Finally, a TMEHA-EDS prototype is manufactured, and experiments are carried out to verify the predicted results. [ABSTRACT FROM AUTHOR]

The interaction mechanism between displacement damage and ionization damage in SiO2 layer has been researched on gate-controlled lateral p-n-p transistor (GLPNP). The sequential irradiation experiments of 400-keV O ions with high dose rate $\gamma $ -rays were carried out, and the degradation and defect evolution results of the device were analyzed by the reciprocal change of current gain change, gate sweep (GS) curve, and deep level transient spectrum (DLTS) results. The results show that there is a negative direct synergistic effect between 400-keV O ions and Co- $60~\gamma $ -rays in GLPNP. At the same time, combined with the GS curve and DLTS results, it can be concluded that the displacement defects of 400-keV O ions in SiO2 layer of GLPNP transistors will capture the holes generated by Co- $60~\gamma $ -rays, thus forming a large number of positive oxide charges ($N_{\mathrm {ot}}$). These $N_{\mathrm {ot}}$ are like “space charge wall,” hindering the movement of protons and holes to the Si/SiO2 interface, and thus inhibiting the generation of interface trap ($N_{\mathrm {it}}$). Due to the decrease of $N_{\mathrm {it}}$ and the increase of positive $N_{\mathrm {ot}}$ , the damage of transistor is weakened. The experimental results show the effects of displacement damage on the ionization effect in SiO2 layer and, more important, provide direct evidence for the space charge model. [ABSTRACT FROM AUTHOR]

Propulsion, levitation and guidance characteristics are the key technology of electro-dynamic suspension Maglev train. An air-core integrated linear synchronous motor with asymmetric primary combined coils is introduced, which can not only simultaneously realize the propulsion, levitation and guidance performances, but also analyze the electromagnetic performance variation of linear synchronous motor under pitching condition. The novel three-dimensional analytical method is proposed for analyzing the transient electromechanical characteristics of the linear synchronous motor. Firstly, the topology structure and operation principle of the linear synchronous motor with pitching attitude are proposed. Secondly, the three-dimensional analytical methods and expressions of electromechanical characteristics are obtained by equivalent circuit method and Fourier decomposition method, such as levitation force, guidance force, propulsion force and pitching torque, etc. Finally, the three-dimensional electromechanical characteristics of the linear synchronous motor are calculated under pitching operation conditions in high-speed maglev train, and the correctness of the analytical theory is verified by the finite element analysis and measured data of on-board motor. [ABSTRACT FROM AUTHOR]