FIELD WINDING DRAG AND NORMAL FORCES OF LINEAR SYNCHRONOUS HOMOPOLAR MOTORS

ABSTRACT

Drag and normal forces caused by the homopolar field winding in a linear synchronous homopolar motor (LSHM), having a segmented secondary of solid iron, are calculated. The analysis is based on the electromagnetic field theory. Numerical results are computed and some experimental results are also given. It is concluded that solid iron segmented secondary is suitable for high speeds (100 to 120 m/s).     

改进的TABU法在异同步电动机优化中的应用

本文阐述了适用于全局寻优的ＴＡＢＵ随机搜索法的基本原理及其改进措施,并用标准的实验函数对它的可靠性和寻优效率进行了验证。最后对ＴＡＢＵ随机搜索法在大型异同步电动机优化设计中的应用进行了研究。     

ACTIVE DAMPING OF MAGLEV VEHICLES USING SUPERCONDUCTING LINEAR SYNCHRONOUS MOTORS

ABSTRACT

This paper explores the use of linear synchronous motor control to provide active damping for magnetically-levitated vehicles. Using a single LSM, only heave and surge damping can be provided, but, with a dual LSM, roll and yaw damping can also be achieved. The paper gives design data applicable to the reference design of theCanadian 500 km/h Maglev system.     

基于SIMULINK的异步电机的建模与仿真

利用MATLAB软件中的动态仿真工具SIMULINK,构建了异步电机的仿真模型,并通过实验验证了所建电机模型的可行性、与实用性。     

ASYNCHRONOUS PERFORMANCES OF HYSTERESIS MOTORS UNDER UNBALANCED CONDITIONS

ABSTRACT

The torque-speed curves of an hysteresis motor under unbalanced conditions are computed by a numerical method. The magnetic characteristic of the rotor ring is represented by the Preisach-Néel's model. This method takes into account the minor loops which appear on the B(H) characteristic in the case under consideration. Computed and experimental curves are compared. This work shows that eddy currents are of no importance on the shape of these curves     

高压异步电动机的故障诊断及综合保护

本文详细分析了高压异步电动机的故障特征及其现有保护的不足。基于对称分量法理论，本文提出了基于检测负序、零序电流及电流幅的电动机保护方法，该方法能够覆盖高压电机常用故障，并可实现对故障类型的自动诊断，实现了高压电动机的智能化综合保护。     

带冲击负载同步电动机的数字仿真

本文推导了带冲击负载同步电动机数字仿真的数学模型,对这类运行方式下电动机的行为进行了研究。并分析了其励磁调节、最大负载和稳定域及安全域等技术性能指标。     

混合励磁直线同步电机的磁场与推力

介绍了一种混合励磁直线同步电机，它的气隙磁场由磁极上的永磁体和电励磁绕组共同提供，采用有限元方法研究了气隙磁场并计算了电机的推力，实验结果很好地验证了有限元分析的结果，另外还提供了一个与同结构电励磁电机进行推力对比的实验结果。研究表明混合励磁直线同步电机的磁场可调，推力大而且变化灵活，既具有永磁直线同步电机的优点，又具有电励磁直线同步电机的优点。     

高效永磁同步电动机

本文阐述了高效永磁同步电动机的设计特点及运行特性。通过ＮｄＦｅＢ永磁同步电动机与感应电动机的性能比较，指出了ＮｄＦｅＢ永磁同步电动机可以获得高效、节能的效果。     

RUN-UP RESPONSE OF POLYPHASE PERMANENT MAGNET SYNCHRONOUS MOTORS

Abstract

An analysis to predict the transient run-up response of permanent magnet synchronous motors is drived based on the d and q axes model. It is based on the segmental reluctance approach with the addition of permanent magnets in the rotor. The computed simulation of the run-up characteristics are provided for variations in the values of stator resistance and permanent magnet excitation. A series of test results of a 3-phase, 2-pole, 1 hp permanent magnet motor are presented In order to verify the theoretical analysis. Effects of stator resistance on the air gap flux are also recorded experimentally. A reasonably close agreement between the measured and calculated values is obtained     

COMBINED FINITE ELEMENT AND ANALYTICAL METHODS FOR ROTOR DESIGN OF PERMANENT MAGNET SYNCHRONOUS MOTORS

ABSTRACT

While design procedures for conventional induction and synchronous machines are now mature and constrained by frame sizes and standards, there are opportunities to use modem CAD techniques to exploit the unique capabilities and characteristics of permanent magnet synchronous motors (PMSM). This paper presents a design methodology involving the use of an analytical model based on generalized machine theory, complemented by finite element analysis. The synergistic interaction of these two methods allows an engineer to design a PMSM to specific requirements with confidence. The effects of machine airgap and of the span angle and thickness of the permanent magnets are evaluated. A set of design specifications and a goodness function are established to select the preferred rotor geometry for a 30 hp prototype permanent magnet synchronous motor.     

三相异步电机初始方案设计专家系统

本文描述了三相异步电机设计专家系统的总体结构，阐述了在专家系统的指导下进行三相异步电动机初始方案设计的方法，体现了用专家系统的方法设计电机的智能性。     

DC BRAKING CHARACTERISTICS OF DOUBLE-SIDED LINEAR INDUCTION MOTORS

ABSTRACT

An analysis of dc braking performance of linear induction motors is presented. Specific phenomena such as longitudinal end-effects and transverse edge-effects are taken into account. Computed results are compared with test results available for the dc braking characteristics of the existing largest double-sided linear induction motor.     

同步电动机群单机异步起动仿真研究

本文为了研究同步电动机群单机异步起动问题,提出了不同的起动电机与运行电机仿真模型,并对输电线路阻抗加以考虑,同时根据起动电机在起动过程的不同阶段采用合理的转矩计算公式。数学模型均采用精确的Park方程描述,并用Matlab语言对其进行仿真,得出结果与实际吻合。     

AN EXPERIMENTAL STUDY OF A HOMOPOLAR LINEAR SYNCHRONOUS MOTOR

Abstract

This paper presents some experimental results obtained from a small homo-polar linear synchronous motor which has been tested on the two-metre test wheel facility at the University of Toronto. The primary of the motor has both armature and field windings while the secondary consists of alternately-placed solid iron poles on the wheel rim. A short three-pole primary has been used so that end effects are accentuated. Test results are presented over a wide range of operating speed, load angle and winding currents. These results indicate that the motor is a promising contender for urban transit propulsion.     

A LINEAR TRANSFER FIELD MACHINE FOR ASYNCHRONOUS MODE OF OPERATION

ABSTRACT

For the first time, this paper describes a working model of a novel linear transfer field machine along with an equivalent circuit analysis method for the asynchronous mode of operation In the sinusoidal steady-state. The machine is found to have a thrust-speed characteristic like unto that of the flat linear induction machine with a conducting sheet secondary. Analysis of performance is made for values of speed across the range from standstill to synchronous speed. Laboratory measured data are compared with calculated values for standstill operation.     

NUMERICAL TREATMENT OF TRANSVERSE EDGE EFFECTS IN LINEAR INDUCTION MOTORS

Abstract

A 3-dimensional-field analysis is presented for the treatment of finite-width effects in linear induction motors (LIM). Account is taken of the effects of stator fringing and rotor-end-portion leakage. The model allows for a finite iron height and width, an arbitrary lateral secondary displacement, and the secondary iron width different from the primary iron width. The method used involves numerical solution of difference equations for the magnetic vector potential as well as a scalar potential. The performance such as thrust, real and reactive power are obtained from the vector potential, and the induced primary voltage. An equivalent circuit with a secondary leakage reactance and modified finite-width correction factors is proposed.     

LATERAL FORCES IN LINEAR RELUCTANCE MOTORS

ABSTRACT

Linear reluctance motors (LRMs) are proposed to provide traction and lift force to magnetically-suspended vehicles for urban advanced transport systems. LRMs are similar to Linear Synchronous motors except that there is no dc field excitation. The steady-state and dynamic performance of LRMs has been the subject of several technical publications, however lateral forces has not been reported earlier. In this paper the lateral forces in an LRM with a segmental rotor is studied. These forces are created when the stator and rotor (or track) are shifted transversely from the symmetrical position. Static lateral forces on an LRM are predicted using an idealized model and was found to compare favorably to measured values. Lateral forces were found to increase until the transverse-displacement to stator-width ratio reaches 14.5% and drops thereafter. This ratio should not be exceeded if the benefit of the lateral restoring force is to be obtained. Experimental results are reported showing variation of lateral, normal and tangential forces of an LRM with load angle at fixed transverse displacements. These force characteristics are also useful for control engineers to help devise a suitable control strategy for an LRM while in suspension conditions     

无轴承永磁同步电机的转子磁场定向控制研究

无轴承永磁同步电机由于功率密度大、转矩脉动低等优良特性受到了高度重视。文中针对一类表面贴装式无轴承永磁同步电机，详细推导出径向悬浮力表达式，建立了准确的数学模型。针对电磁转矩和径向悬浮力之间耦合的特点，采用了基于转子磁场定向的控制策略来实现这类无轴承永磁同步电机的非线性解耦控制。实验证明了该控制算法的有效性。该控制算法对插入式转子结构和内装式转子结构的无轴承永磁同步电机的控制系统设计具有一定的借鉴作用。