基于Ansoft的开关磁阻电机设计和有限元分析

开关磁阻电机作为一种机电一体化电机,其电磁关系较为复杂。首先对开关磁阻电机进行电磁设计,得到了性能曲线;然后利用有限元的方法进行了三维静态磁场和瞬态磁场的分析,得到了开关磁阻电机的静态磁场分布和瞬态响应曲线。为开关磁阻电机的设计、仿真、控制提供了依据。     

基于MATLAB的开关磁阻电机非线性建模仿真

由于开关磁阻电机SRM结构及运行原理的特殊性,使得分析和设计较其它电机更为困难。基于在分析开关磁阻电机数学模型的基础上,借助于M ATLAB/S IMUL INK搭建了电流斩波控制方式下开关磁阻电机的非线性仿真通用模型。根据此模型,对一台六相12/10结构样机进行了仿真,仿真结果证明了该模型的有效性。该模型为分析和设计开关磁阻电机控制系统提供了一种有效的工具。     

三相6/4极开关磁阻电机参数设计与有限元分析

分析了三相6/4结构开关磁阻电机结构和工作原理,给出了其数学模型。详细介绍了开关磁阻电机参数设计方法,并给出一台3 kW三相6/4结构开关磁阻电机实验样机参数。利用有限元分析软件Ansoft/Maxwell对该样机的矩-角特性和磁路结构进行了仿真分析,并进行初步实验研究,仿真和实验研究结果验证了参数设计方法的正确性。     

SR电机起动转矩的仿真分析与实验

开关磁阻电机(Switched Reluctance Motor)起动性能优良，具有起动电流小而起动转矩大的优点。本文首先从分析开关磁阻电机电磁转矩的基本理论入手，介绍了应用ANSYS软件对开关磁阻电机磁路磁场的仿真；利用仿真计算所得磁化曲线族，对开关磁阻电机的起动转矩进行编程仿真计算；根据仿真计算结果对开关磁阻电机的起动性能进行了详细的分析；比较了两种典型的起动控制方案的优缺点；并提出了改善开关磁阻电机起动性能的几个方案。最后，介绍了开关磁阻电机起动转矩测试台的构成和测试方法；并以一台三相6/4结构开关磁阻样机进行了实验验证，结果和仿真计算十分相似，同时也证明了对开关磁阻电机起动转矩仿真计算的正确性。     

垂直轴开关磁阻风力发电系统研究

以6相12/10开关磁阻发电机为对象,对垂直轴开关磁阻风力发电系统进行理论研究。系统概述了其性能特点、发电原理,控制方法、建模方法,并基于MATLAB/Simulink平台结合Ansoft/Maxwell 2D电磁分析对开关磁阻电机应用于垂直轴风力发电系统可行性进行仿真验证,仿真结果与理论相符合,为系统一体化实物设计提供参考与支持。     

平面开关磁阻电机电磁性能分析

为了进一步完善平面开关磁阻电机的设计理论及其结构优化设计方法,本文深入研究平面开关磁阻电机电磁性能。详细介绍了平面开关磁阻电机结构,理论分析了平面开关磁阻电机电磁模型,利用Ansoft Maxwell建立了平面开关磁阻电机三维瞬态有限元模型,基于建立的有限元模型深入探讨了电磁推力、法向力与励磁电流、气隙长度、动子轭厚度之间的关系,研制了一台平面开关磁阻电机样机,并搭建了样机测力系统,进行了样机电磁性能的实验研究。研究结果表明,实验结果与有限元仿真结果相吻合,验证了提出的平面开关磁阻电机电磁性能分析方法的有效性和正确性。     

电动工具用高速两相开关磁阻电机研究

本文基于电动工具驱动对高速两相开关磁阻电动机进行了研究开发。首先由单相交流串励电机驱动的打磨机工具的性能要求和尺寸限制,给出两相开关磁阻电机的额定参数及主要尺寸,然后对电机进行了电磁设计研究,重点对其阶梯气隙进行优化设计研究,以满足电机的自起动能力和低转矩脉动要求,并对设计计算结果进行了电磁场有限元仿真验证;其次研究开发了两相开关磁阻电机驱动控制系统;最后进行了样机试制和样机试验,试验结果验证了分析计算的正确性及该种电机用于高速低成本驱动的可行性。     

基于转矩误差PWM-DITC开关磁阻电机控制策略

研究了开关磁阻电机直接瞬时转矩控制的方法,针对开关磁阻电机转矩脉动大,提出了一种基于转矩误差PWM-DITC开关磁阻电机控制策略,利用Matlab/Simulink对开关磁阻电机PWM-DITC控制策略进行建模与仿真,仿真结果表明,PWM-DITC控制结构简单,不需要进行电流控制,直接从参考转矩和当前输出转矩进行比较得到每一相的开关状态,能有效地抑制开关磁阻电机的转矩脉动。将滞环控制策略和改进的PWM-DITC控制策略相比较,得出开关磁阻电机PWM-DITC控制策略实现简单,响应速度快,可提高系统的性能,能较好地抑制转矩脉动。     

一种相间耦合型短磁路开关磁阻电机的研究

提出一种相间耦合型多相短磁路开关磁阻电机,电机转子为铸铝加硅钢片的组合,确保磁通按短磁路闭合,可以提高功率密度,降低铁耗和制造成本,减轻重量,提高散热能力。分析了电机的结构特点,以五相10/8极开关磁阻电机为例,使用有限元法对电机主要性能进行仿真验证,分析了径向力波的谐波成份,并与普通结构开关磁阻电机进行对比,结果表明新型短磁路多相开关磁阻电机在低速或高速运行时均明显提升了平均转矩、功率密度、效率等性能,为高功率密度、高效率电机的设计提供了新思路,具有重要的理论和实用价值。     

开关磁阻电机矩角特性的研究与应用

分析了开关磁阻电机矩角特性的计算方法,在此基础上用有限元磁场计算出开关磁阻电机的磁化曲线族,根据这些数据仿真给定电流下的矩角特性,并分析了矩角特性曲线与电感变化率的关系.设计并制作了一台矩角特性测试平台,试验结果验证了仿真理论的正确性.最后分析了矩角特性在研究开关磁阻电机起动性能等方面的应用,从而指导开关磁阻电机的优化设计.     

The modeling of switched reluctance machines with magneticallycoupled windings

This paper presents a method of modeling switched reluctance motors with strongly coupled windings, such as switched reluctance machines (SRMs) with fully pitched windings or with commutating windings. These machines are particularly difficult to model because, unlike a conventional SRM, the flux linking any one winding of the machine is a nonlinear function of rotor position and all phase currents. The problem is overcome by breaking down the instantaneous flux linkages and currents in each phase to give the flux and magnetomotive force (MMF) in each tooth of the machine. The flux and MMF per tooth can then be linked in the model by a simple lookup table, determined from either simulation or measurement. The paper describes the simulation method in detail and then gives extensive comparisons between measurement and simulation results for an SRM with fully pitched windings, operating over a range of operating conditions. The results presented also serve to give an insight into the method of operation of these rather complex machines     

新型SRM功率变换器主电路研究

提出了一种新型SR电动机功率变换器主电路 ,和传统的不对称半桥电路相比较 ,新型电路所使用的主开关器件个数少 ;实现了主开关器件的零电压关断 ,改善了开关性能 ;续流时 ,绕组承受的反向电压可达正向导通电压的 2 5倍 ,从而使续流时间缩短 ,输出转矩增加 ,效率提高 ;利用LC谐振电路使续流时储存在电容中的能量转移到相邻相 ,提高了调速系统的功率因数。本文用非线性磁参数法 ,以 3相 6 / 4极SR电动机为研究对象 ,分别对传统不对称半桥电路和新型电路驱动时的稳态性能 ,进行了仿真研究。     

Calculation of the electromagnetic parameters of a switchedreluctance motor using an improved FEM-BIEM-application to differentmodels for the torque calculation

This paper expands on a hybrid numerical method coupling the finite element method (FEM) and boundary integral equation method (BIEM), developed to calculate magnetic fields in a switched reluctance motor (SRM). This hybrid approach is a solution to the issues stemming from the small size and odd shape of the SRM airgap, where meshing an FEM grid is difficult. In the past, the stator and rotor FEM domains kept their actual shapes, which resulted in problems with the definition of the unit outward normal vector n&oarr; at the corner points of the SRM poles. Therefore, the normal derivative of the magnetic vector potential, i.e., the tangential component of the flux density, was undefined at these points. In this paper, a new approach with new definitions of the stator and rotor FEM domains is presented. The new concept defines the SRM airgap as a ring in which circular boundaries permit the correct definition of the normal derivative quantities and exploit the natural Neumann condition. The electromagnetic parameters of a 7.5 kW SRM prototype machine were calculated using this new approach. They compare favorably with test data. Phase magnetization characteristics also have good precision and smoothness. These electromagnetic parameters were then used to assess and compare two different SRM models for the calculation of the torque on the motor shaft, the linear trapezoidal model and the nonlinear model. The comparison between the measured torque and the torque as calculated with the two different models shows that the more simple trapezoidal model should be satisfactory in many cases and could, in particular, be used in automated SRM designs     

New winding configurations for doubly salient reluctance machines

This paper develops the concept of employing a fully pitched winding in a doubly-salient reluctance motor. In a conventional switched reluctance machine, there is complete magnetic decoupling between phases, so that torque is produced entirely due to the rate of change of winding self-inductance. This effectively limits each phase to contributing to positive torque production to a maximum of one-half of the cycle of rotation. If the same machine is wound with fully pitched windings, then it can be shown that the new configuration produces torque entirely as a result of changing mutual inductance between phases, while maintaining a unipolar conduction sequence. Compared with the conventional short-pitched winding machine, far better utilization of the electric circuit results, with each phase contributing to positive torque production for at least two-thirds of the cycle of rotation. A subsequent increase in torque per unit volume inevitably results. The application of such an idea to three-phase switched reluctance motors (SRMs) is developed theoretically and through a series of experimental tests upon a 7.5 kW machine, showing static torque curves for the new machine and comparing them to a conventionally wound SRM     

A Fourier Series Generalized Geometry-Based Analytical Model of Switched Reluctance Machines

A novel invertible generalized flux/current switched reluctance machine (SRM) model based on the Fourier series expansion is presented. This model, which is derived from machine geometry and materials properties, is accurate enough to be used for actual machine representation and can also be simplified for real-time controller applications. Simulation and experimental results illustrate that the proposed modeling approach provides better representation of the SRM than other existing techniques     

A five-phase reluctance motor with high specific torque

An alternative topology for a synchronous reluctance motor (SRM) utilizing a novel five-phase, concentrated winding, wye-connected stator is proposed. The corresponding inverter requires only ten power transistors, each of which operate at a better switch utilization factor than a conventional three-phase, six-transistor bridge. It is shown that this machine is capable of producing about 10% more torque per RMS current flowing through the winding than the normal three-phase SRM     

Effect of Paralleling the Stator Coils in a Permanent-Magnet Machine

As low-voltage machines require smaller number of turns per phase compared to higher voltage machines, it is normal to connect the various stator phase coils in parallel to form the phase winding. The placement of various coil sides in the slot and the difference in the field produced by different poles of the rotor magnet can influence the induced voltage in various coils and the impedance of the coils. The difference in the induced voltages in the various parallel paths results in a circulating current in the winding and will cause increased losses in the machine. The unequal induced voltage and impedance will cause unequal distribution of stator current in the various parallel paths and will impact the torque-ripple contents. This paper will discuss the effects of these unbalanced parallel paths on the machine performance     

探讨大型变频调速矿井提升同步电动机设计的特殊性

针对大型矿井提升同步电动机和为其供电的交-交变频电源的特点,概括介绍了此类电机的电磁、结构等方面的设计要点。在电机电磁设计方面,说明了对于使用变频电源下,如何选择电机容量、额定电压,确定极对数、定子铁心外径及气隙磁密、定子线圈每相串联匝数和定子铁心长度等初步设计需要考虑的问题。进而对详细计算进行说明。在结构设计方面,分别对定转子的组成和定转子线圈结构特点进行了简要介绍。所生产的电机不仅在性能上满足用户的要求,而且经济指标也在逐步提升。     

新型永磁式开关磁阻电机研究

本文介绍一种带永久磁钢的新型开关磁阻电动机。     

Evolutionary computation based multi-objective pole shape optimization of switched reluctance machine

This paper presents the application of elitist Non-dominated Sorting Genetic Algorithm version II (NSGA-II) to determine optimum pole shape design for performance enhancement of Switched Reluctance Machine (SRM). In SRM, torque output and torque ripple are sensitive to stator and rotor pole arcs and their selection is a vital part of SRM design process. The problem of determining optimal pole arc is formulated as a multi-objective optimization problem with the objective of maximizing average torque, minimizing torque ripple and copper loss. In order to account for the geometry as well as for the nonlinearity of material utilized, the Finite Element Method (FEM) is used to determine the performance of the machine. The proposed optimization technique is applied to determine optimal pole shape of an 8/6, four-phase, 5 HP, 1500 rpm SRM. The results show the effectiveness of the proposed approach and confirm the application of NSGA-II as a promising tool for solving SRM design problems. The results obtained by NSGA-II are compared and validated with classical multi-objective approach based on weighted sum method using Differential Evolution (DE) algorithm.