Suspension characteristics of magnetic suspension system by linear induction motor.

Background: In the existing inverse system decoupling methods of bearingless induction motor, the inverse system model is more complex, and it is not easy to realize the independent control of the magnetic suspension system. In this paper, in order to simplify its inverse system model, an independent inverse system decoupling control strategy is proposed. Methods: Under the conditions of considering the current dynamics of torque windings, the state equations of torque system and those of magnetic suspension system are established, and the independent inverse system model of torque system and that of the magnetic suspension system are deduced. The air gap fluxlinkage of the torque system that is needed in the magnetic suspension system is identified by an independent voltage model. After the independent inverse model of torque system and that of magnetic suspension system are connected in parallel, they are connected in front of the original system of a bearingless induction motor. After this, the torque system is decoupled into two second-order integral subsystems, i.e. a fluxlinkage subsystem and a motor speed subsystem, while the magnetic suspension system is decoupled into another two second-order integral subsystems, i.e. the α- and β-displacement component subsystems. The design of the additional closed-loop controller is achieved through the pole assignment method. Result: The obtained inverse model of the magnetic suspension system is independent of the fluxlinkage orientation mode of torque system, and thus the flexibility of the independent control for the torque system and magnetic suspension system is increased. The simulation results have shown that the system has good static- and dynamic-decoupling control performance. Conclusion: The proposed independent inverse system decoupling control strategy is effective and feasible.

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New technology for manufacturing inductors of linear induction motors for magnetic-levitation transport

Transportation systems and technology ◽

10.17816/transsyst201843s1351-364 ◽

2018 ◽

Vol 4 (3 suppl. 1) ◽

pp. 351-364

Author(s):

Vladimir A. Solomin ◽

Andrei V. Solomin ◽

Nadezda A. Trubitsina ◽

Larisa L. Zamchina ◽

Anastasia A. Chekhova

Keyword(s):

Induction Motor ◽

High Speed ◽

Induction Motors ◽

Magnetic Levitation ◽

New Technology ◽

Manufacturing Technology ◽

Magnetic Suspension ◽

Linear Induction ◽

Linear Induction Motor ◽

Linear Induction Motors

Abstract. Background: Significant economic growth in many countries of the world can contribute to an increase in the speed of movement of modern and fundamentally new vehicles. This will increase the turnover of goods during the transportation of goods, revive international trade, increase the comfort of passengers and reduce their travel time. Aim: The solution of this problem is the development and wide application of high-speed magnetic-levitation transport (HSMLT) with linear traction engines. It is promising to use linear induction motors (LIM) for the HSMLT drive, which can have various design versions. Linear induction motors come with a longitudinal, transverse and longitudinal-transverse closure of the magnetic flux. LIM inductors can be installed on both high-speed transport crews and in the HSMLT track structure, as it was done in the People’s Republic of China, where express trains on magnetic suspension connect Shanghai with the airport and reliably operate for more than 10 years. The main elements of the inductor of a linear induction motor are a magnetic core (ferromagnetic core) a multiphase (usually three-phase) winding. With the development of high-speed magnetic-levitation transport, the issues of improving the manufacturing technology of various HSMLT devices, including the methods for producing inductors of linear induction motors, will become increasingly relevant. Traditionally, LIM inductors are assembled from pre-manufactured individual parts. Methods: An integral technology for manufacturing inductors of linear induction motors for high-speed magnetic-levitation transport is proposed and considered by the method of spraying materials onto a substrate through replaceable stencils. The new technology eliminates the alternate manufacture of individual assemblies and parts and their subsequent assembly to obtain a finished product. A method for determining the size of stencils for manufacturing one of the inductor variants of a linear induction motor is proposed as an example. Conclusion: Integral manufacturing technology is promising for the creation of high-speed magnetic-levitation transport.

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Dynamic characteristics of linear induction motor for urban transit under constant V/f drive

Electrical Engineering in Japan ◽

10.1002/eej.4391100711 ◽

1990 ◽

Vol 110 (7) ◽

pp. 102-109

Author(s):

Sakutaro Nonak ◽

Nobuo Fujii ◽

Yasunobu Kojima

Keyword(s):

Induction Motor ◽

Dynamic Characteristics ◽

Urban Transit ◽

Linear Induction ◽

Linear Induction Motor

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Magnetic suspension mechanism using rotary permanent magnets

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209412 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 977-983

Author(s):

Koichi Oka ◽

Kentaro Yamamoto ◽

Akinori Harada

Keyword(s):

Permanent Magnets ◽

Suspension System ◽

Magnetic Suspension ◽

Horizontal Force ◽

Mechanical Contact ◽

New Type ◽

Magnetic Suspension System

This paper proposes a new type of noncontact magnetic suspension system using two permanent magnets driven by rotary actuators. The paper aims to explain the proposed concept, configuration of the suspension system, and basic analyses for feasibility by FEM analyses. Two bar-shaped permanent magnets are installed as they are driven by rotary actuators independently. Attractive forces of two magnets act on the iron ball which is located under the magnets. Control of the angles of two magnets can suspend the iron ball stably without mechanical contact and changes the position of the ball. FEM analyses have been carried out for the arrangement of two permanent magnets and forces are simulated for noncontact suspension. Hence, successfully the required enough force against the gravity of the iron ball can be generated and controlled. Control of the horizontal force is also confirmed by the rotation of the permanent magnets.

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