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A novel transverse-flux switched-flux linear motor (TFSFLM) is developed in this paper, which has high thrust force density and low cost due to combining the advantages of transverse-flux structure and switched-flux structure. Based on 3D FEM model, two main parameters of motor configuration are investigated to acquire a higher thrust force. Some fundamental performance, such as flux-linkage, back-electromotive force (back-EMF), inductances and so forth, are demonstrated as well. According to the property of back-EMF, two different drive patterns, i.e. brushless AC (BLAC) and brushless DC (BLDC), are investigated in the meantime. The results show that this kind of electric machine is more suitable for BLDC operation. The conclusions will benefit the design and control of novel switched-flux electric machines.

An H-module linear actuator (HMLA) is proposed in this paper for medical equipment applications. Compared to the existing linear actuators used in medical equipment, the proposed H-module linear actuator has much lower normal force, which makes use of an additional air-suspension system unnecessary. The working principle of the HMLA is illustrated in detail in this paper, and its tangential and normal force characteristics are demonstrated by using finite element analysis (FEA). It is proved that the normal force of the HMLA can be greatly reduced without sacrificing the useful tangential force component.

For computer numerical control (CNC) machine tools, the double side air-cored permanent magnet linear servo motor (DAPMLSM) is suitable for high-speed and high-precision servo feed systems. But it also has thrust ripple caused by non-sinusoidal magnetic field distribution. Finite element analysis (FEA) was used to study motor characteristics, and the computer simulation results match well with the prototype data. It indicates FEA method is accurate. Based on that, the influences of DAPMLSM main structure dimensions were analyzed. The air-gap and magnet thickness mainly affect the amplitude, and the pole-arc coefficient affects both amplitude and its distribution. The distribution condition of the magnetic field in the air-gap could be improved effectively by optimal design of the pole-arc coefficient, furthermore the thrust fluctuations is reduced.

A traction power supply system which adopted separately excited DC generator sets was designed. The desired output voltage was kept constant by regulating the rotary speed of induction motor and field current. In order to realize almost ripple-free operation in the entire speed range and achieve the position sensorless control, direct torque control based on space-vector modulation (DTCSVM) strategy based on mutual model reference adaptive system (mutual MRAS) was used for induction motor. DTCSVM is able to reduce the acoustical noise, the torque, flux, current, and speed pulsations during steady state. Mutual MRAS was adopted to implement a position sensorless DTC of an induction motor. Simulation and experiment on the traction power supply system indicates that the proposed control method produces better results than the classical DTC. The output voltage of the power supply system remains constant when load changes. The overall system performance was verified by experiments.

The method of position detection for PMLSM by linear Hall-effect sensors is studied in this paper. The influence from motor's back iron to detection is discussed and analyzed. Based on finite element analysis of the motor's magnetic flux and considering the dimension limit of motor in practice, the best mounting position of the sensor is given to eliminate the influence of the back iron, and improve the accuracy of the detection. This mounting position of the sensor determined by analysis is also proved to be the best by comparing the accuracy of detection results under different mounting positions. This method of position detection for PMLSM offers advantages over other methods, such as simplicity, low cost, high precision and accuracy, and it is very suitable for linear servo system.

The large air gap linear induction motor (air gap length is greater than 10 mm) is well used in metro, light rail now, and also will have a nice future in Low-speed Maglev Vehicle. There are many differences between large air-gap linear induction motor and the small air-gap ones. It is necessary to do some research for the characteristics and driven technique of large air-gap linear induction motor. The paper introduced the DUNCUN equivalent circuit model for linear induction motor. By implementing FEM analysis of one large air-gap linear induction motor, the parameters for the DUNCUN equivalent circuit model were extracted. Then taking dynamic longitudinal end effect of this LEVI into consideration, the secondary flux oriented control simulation model of this LEVI is developed. Via simulation analysis, some of the key points about field oriented control was discussed. As a result, they can supply some good tips to driven system design of this kind of motor.

Virtual Instrument (VI) is an outcome with the development of computer technique, modern measuring and testing technique, and electronic instrument technique. It is a new vivid kind of measuring instrument with well outlook. Compared to the testing system of conventional rotary motor, the one of three-phase linear induction motor (LIM) is quite different with the measuring of thrust and normal force. By virtual of the static testing system of 3-phase LIM developed by using PC as the CPU, based on PCI-6229 board, Lab VIEW as the software developing platform, not only the structure of the system hardware have been simplified, but also the reliability of the system have been improved considerably so that the measuring precision and stability of all parameter could have been ensured.

This paper focuses on the application of tubular PMLSM in oil field. First, use ANSYS and magnetic reluctance circuit method to analysis and compute the motor respectively. After that, get the parameters of the motor. These parameters are the basic ones to build a mathematic model in SIMULINK. In order to drive the motor and get a steady speed, we use the PI controller. The PI control system is a simple system, so it has high reliability. Of course, for permanent magnet motor we use id=0 control strategy.

This paper presents a configuration of a long stator linear synchronous motor (LSLSM) for maglev vehicle systems; the foundational state-space model is developed for static and dynamic analysis. The relative effects between propel and the levitation force within the stator and the mover are discussed. The simulation results of the propelling force and the levitating force are also presented.

This paper deals with the application of linear electric motors in postal mechanical systems. The author has accomplished the application of several different linear electric motors to different postal machines, i.e., belt conveyers, package sorting machines, push-type suspending conveyers, etc. Postal machines driven by linear electric motors have advantages such as simple construction, high efficiency, noise reduction, ease of control, etc.