A Position Stepping Method for Predicting Performances of Switched Reluctance Motor Drives

This paper presents a novel numerical method, which will be referred as the position stepping method (PSM), to predict the performances of switched reluctance motor (SRM) drives. The 2D bicubic spline is employed to generate the finite rectangular elements. The 2D bilinear spline is used to model the nonlinear magnetic characteristics in SRMs. Consequently, the conventional nonlinear first-order differential voltage equation for describing the performances of SRM drives can be simplified into an analytical expression in terms of the current with respect to the rotor position. Furthermore, the position stepping algorithm is developed according to the boundary and continuity conditions, to accurately and rapidly compute the current from the proposed current expression. Simulated and measured current waveforms are reported to validate the developed PSM. The CPU execution time required by the PSM compares very favorably with that of the analytical method. Overall, this paper provides an accurate and speedy approach to predict the currents and torques of SRM drives.     

功率变换器叠层母排优化设计

以60kW开关磁阻电机系统中采用三相不对称半桥电路的功率变换器为例,设计叠层母排方案,通过电路仿真,研究各部分杂散电感对电路瞬态特性的影响。分析母排设计中各几何因素对杂散电感影响,引入影响因子,对母排设计中各因素的影响程度进行评估。据此,为母排最优设计提供依据。     

基于模糊控制的新型永磁开关磁阻电机控制系统研究与设计

提出了一种新型永磁式开关磁阻电机。通过对传统电机结构上进行了改进,在定子上加入永磁材料,使得电机成为混合励磁电机,分析了其结构及原理等,并探讨了其调速方式,把模糊控制运用于调速系统,设计了其调速系统的软硬件,最后对其样机进行了试验,对开关磁阻电机的改进具有一定指导意义。     

非对称中点钳位型逆变电路的开关磁阻电机模型预测直接转矩控制方法

针对开关磁阻电机(SRM)转矩脉动过大的问题,提出一种非对称中点钳位型逆变电路的模型预测直接转矩控制方法,该控制方法基于开关磁阻电机的电感特性及转矩产生原理对扇区进行重新划分,对非对称中点钳位型逆变电路的基本工作模式进行分析并选取基本电压状态,根据直接转矩控制原理及扇区实际意义制定新型矢量选择方案,减少每个控制周期中的...     

An Improved Proportional Integral Estimator of the Stator Resistance for a Direct Torque Controlled Induction Motor

In this paper, an improved PI （proportional integral） stator resistance estimation for a DTC （direct torque controlled） induction motor is proposed. This estimation method is based on an on-line stator resistance correction regarding the variations of the stator current estimation error. In fact, the input variable of the P1 estimator is the stator current estimation error. The main idea is to tune accurately the stator resistance value relatively to the evolution of the stator current estimation error gradient to avoid the drive instability and ensure the tracking of the actual value of the stator resistance. But there is an unavoidable steady state error between the filtered stator current modulus and its estimated value from the dq model of the machine which is due to pseudo random commutations of the inverter switches. This may deteriorate the performance of the proposed fuzzy stator resistance estimator. An offset has been introduced in order to overcome this problem, for different speed command values and load torques. Simulation results show that the proposed estimator was able to successfully track the actual value of the stator resistance lbr different operating conditions.     

开关磁阻电机驱动系统的发展及应用

开关磁阻电机驱动（SRD）系统是继变频驱动系统、无换向器电动机驱动系统之后发展起来的一种新型的、性价比很高的节能调速控制系统。本文就SRD系统的组成、结构、工作原理、特点、国内外的发展情况进行了系统的论述,对目前SRD系统存在的问题及研究课题进行了分析。同时,为推广应用SRD系统提出了一些建议和意见,可供有关人员和企业系统了解及推广应用SRD系统做参考。     

Semiactive and Active Piezoelectric Vibration Controls for Switched Reluctance Machine

This paper presents two vibration control approaches using piezoelectric inserts applied to a switched reluctance machine (SRM) in order to reduce acoustic emission. The semiactive approach, called synchronized switch damping, consists of a particular voltage processing that increases the electromechanical energy conversion of the piezoelectric insert and leads to effective vibration energy dissipation. Piezoelectric inserts can also be considered as actuators: the active technique aims at imposing an adequate force in order to compensate the structure strain originated by the electromagnetic forces. These two techniques are compared on a single-phase structure mechanically similar to that of an SRM. Advantages and drawbacks depending on the chosen technique are then discussed.     

Piezoelectric Actuator Design and Placement for Switched Reluctance Motors Active Damping

This paper describes the design and the placement of piezoelectric actuators on switched reluctance motors by means of a genetic algorithm (nondominated sorting genetic algorithm II) for the purpose of reducing stator vibrations. Two distinct approaches are presented: one energy-related and the other based on a minimization of the resultant displacement. These methods lead to design and placement strategy for the piezoelectric actuators. A number of optimal actuators obtained using these kinds of approaches is also compared with mechanical finite-element simulations. At last, a solution is achieved in order to validate optimal placement using positive position feedback active filtering.      

Efficiency Improvements of Switched Reluctance Motors With High-Quality Iron Steel and Enhanced Conductor Slot Fill

In this paper, a comparison of efficiencies is put forward for a set of test machines constructed from several different types of low-loss magnetic steels. These are laminated amorphous alloys, 6.5% high silicon steel, and general-purpose low-loss silicon steel. Efficiency and characteristics are compared by experiment. The test switched reluctance motors are shown to have more than 95% efficiency at an output of about 2 kW. The effectiveness of an enhanced winding slot fill factor is also evaluated. The use of the high silicon steel is more practical at improving the efficiency as opposed to the use of increased slot fill factor.      

Transient Behavior of Induction Motor Flux and Torque During Run-Up

This paper analyses the various flux components that exist within symmetrical three phase cage induction motors, and how they manifest themselves as torque oscillations during run-up. A small, a medium and a large motor are evaluated to show that recent explanations of this phenomena by way of only the airgap flux may be misleading due to a lack of generally applying to motors of different sizes and parameter combinations.     

一种直流力矩电机EGR位置闭环控制算法

为了满足直流力矩电机废气再循环(EGR)对于位置控制响应快、超调量小、稳态精度高的要求,在分析经典比例积分微分(PID)控制算法的基础上,根据直流力矩电机EGR结构,提出一种精确数学模型和抗积分饱和变结构PID混合的控制算法,采用该控制算法后,系统具有较高的动态响应特性,并且系统匹配标定工作量减少.通过仿真验证和发动机台架实验验证了该控制算法的有效性.     

基于试验数据的锅炉钢结构高强度螺栓轴力与扭矩关系回归分析

为了解决锅炉机组钢结构高强度螺栓转角法施工过程中量化的检验标准,介绍了采用实验的方法,得到高强度螺栓扭矩与轴力的对应值,并采用线性回归分析方法建立高强度螺栓扭矩与轴力的理论关系模型,结合实际施工、检验条件及要求,为保证检验方便、可行,最终以图或表的形式提供转角法高强度螺栓扭矩与轴力的对应关系.     

永磁同步电机直接扭矩控制的仿真研究

分析了永磁同步电机的直接扭矩控制原理,并在Matlab/Simulink软件环境下建立了永磁同步电机的直接扭矩控制系统模型,对各个仿真模块进行了详细阐述.仿真结果表明,直接扭矩控制以扭矩为控制变量,扭矩响应快速准确,对建立混合动力车基于扭矩分配的整车仿真模型具有重要意义.     

Non-Simultaneous Reclosing Air-Gap Transient Torque of Induction Motor: Part I, Analysis and Computation Logic

Non-simultaneous reclosing of an induction motor involves three transient steps: the switching off, the reclosing of two of the three switch poles, and the reclosing of the third pole. Each step is initiated and superimposed successively to give a complete transient picture. The analysis and the computation logic are given in this part. The application of the analytical results and the discussion of the American National Standard, ANSI C50.41, for reclosing of induction motors, are given in Part II.     

基于螺栓装配技术中扭矩法与扭矩/转角法比较与应用研究

介绍可控螺纹联接技术的机理,对扭矩法和扭矩/转角法2种拧紧工艺进行了分析与比较。指出:影响螺纹联接装配的实质———螺栓的轴向预紧力,以及在2种控制方式下,轴向力分布和散差之间的不同。文章还结合生产实践,论证扭矩/转角法拧紧工艺在发动机关键螺栓联接中的应用价值。     

Combined Flux Observer With Signal Injection Enhancement for Wide Speed Range Sensorless Direct Torque Control of IPMSM Drives

This paper proposes a motion-sensorless control system using direct torque control with space vector modulation for interior permanent magnet synchronous motor (IPMSM) drives, for wide speed range operation, including standstill. A novel stator flux observer with variable structure uses a combined voltage-current model with PI compensator for low-speed operations. As speed increases, the observer switches gradually to a PI compensated closed-loop voltage model, which is solely used at high speeds. High-frequency rotating-voltage injection with a single D-module bandpass vector filter and a phase-locked loop state observer with a new synchronization procedure are used to estimate the rotor position, which is needed only by the current model in stator flux observer at low speeds. A new rotor speed estimator for the whole speed-loop range, based on the stator flux speed estimation with a new dynamic correction depending on estimated torque, is proposed and tested. Extensive simulation results and significant experimental results provided good performance for the proposed IPMSM sensorless system in more than 1:1000 speed range, under full-load operation, from very low speeds (1 r/min experimental) up to rated speed.     

Saturation Modeling and Stability Analysis of Synchronous Reluctance Generator

A new method of representing magnetic saturation in synchronous reluctance generator has been proposed in this paper. A linearized model of synchronous reluctance generator has been developed applying the proposed saturation model to perform the steady-state stability analysis. The effect of $d$ - and $q$-axis saturation on the steady-state stability of a synchronous reluctance generator has been investigated using the proposed linearized machine model. Effects of different loading conditions such as active power, reactive power, and power factor on the steady-state stability have also been looked into. Moreover, the effect of $d$- and $q$-axis saturation on the transient stability analysis has been investigated in the case of a three-phase symmetrical ground fault at the machine terminals.