感应电机能量最优化控制的研究

感应电机能量优化控制常根据电机静态模型采用恒转差频率控制。但该控制方案会导致调速系统的动态性能和稳定性降低。从感应电机的动态模型出发,提出了一种借助转子磁链控制实现感应电机能量优化的控制方案。根据外环给定电磁转矩的不同,调整内环转子磁链给定值,以达到能量优化控制的目的。在调速过程中,控制方案确保转子磁链紧跟给定值,使输出的电磁转矩紧跟给定值。因此,系统的稳定性、动态性能良好。     

电流驱动按定子和气隙磁链定向的矢量控制

按转子磁链定向的矢量控制系统与转子参数有关,使得交流调速系统的性能受到影响。本文采用电流输出控制型逆变器,按定子磁链和气隙磁链定向的矢量控制,推导解耦控制方程,附加去耦项,实现系统的彻底解耦控制,磁链检测和转矩检测不含转子参数,仿真结果表明,新系统提高了磁场定向的准确性和解耦能力,改善闭环控制的动态性能和鲁棒性。     

从矢量的角度讲解交流电机矢量控制

为适合于少学时交流调速系统课程教学的需要,使学生容易理解矢量控制在交流电机调速以外的应用,本文提出了从矢量的角度讲解交流电机矢量控制的思路。从电磁转矩关于定、转子电流和转子位置角的瞬时值表达式入手,推导出了电磁转矩关于定子电流矢量和三个磁链矢量的表达式。利用这些表达式和矢量图,直观阐释了经磁场定向后定子电流转矩分量与励磁分量实现解耦的机理。     

基于DSP的无速度传感器直接转矩控制系统设计

直接转矩控制是一种新颖的异步电机调速方案,它是在定子坐标系下,通过检测定子电流、电压等变量直接计算和控制电动机的磁链和转矩,获得转矩的高动态性能.DSP具有运算速度快、处理能力强和实时性好等特点,这使得很多复杂的控制策略和算法得以实现.本文提出了一种基于THS32OF2812的无速度传感器直接转矩控制系统,给出了硬件设计和软件设计方案.     

一种新型永磁同步电动机的直接转矩控制方法

基于永磁同步电动机的转矩和磁链方程，介绍了一种改进的直接转矩控制方法。在该控制方法中，引入了一种新的电压空间矢量调制技术，这种调制技术的特点是把电动机的转速作为开关表的一个输入量，实现了定子电压空间矢量的精确选择，有效的降低了转矩、定子磁链和定子电流的波动。仿真实验结果验证了这种控制方法的有效性。     

基于滑模变结构的高速同步电机直接转矩控制

针对高速同步电机,文章研究了基于滑模变结构的无传感器直接转矩控制。该控制方式将滑模变结构和直接转矩控制相结合,用以改善电机定子磁链和电磁转矩的脉动。本文对基于滑模变结构的无传感器高速同步电机直接转矩控制和传统直接转矩控制系统性能中的定子电流、电磁转矩和定子磁链轨迹分别进行了仿真对比分析。仿真结果表明,采用基于滑模变结构的无传感器直接转矩控制方式可以减小定子电流和电磁转矩的脉动,定子磁链频带宽度变化较小,适合对高速同步电机控制。     

异步电动机调速系统的滑模直接转矩控制方法

在交流调速技术中，直接转矩控制技术的特点是具有快速的动态响应特性和很强的鲁棒性，这种控制方法存在的问题是在稳态运行时会出现转矩和磁链的脉动。为了降低转矩和磁链的脉动，本文基于滑模控制方法介绍了一种新的直接转矩控制方法，其特点是继承了直接转矩控制方法的优点，同时降低了稳态时转矩和磁链脉动，改善了调速系统的低速性能。最后对整个调速系统进行了实验研究，实验的结果表明了这种控制方法的有效性。     

基于神经滑模变自抗扰控制的感应电机变频调速系统设计

基于强化感应电机变频调速系统的调速质量及响应速度的考量,文章设计出建立在神经滑模变自抗扰控制的感应电机变频调速系统。应用ADRC控制,在基础上提升了调速系统控制品质与控制精准性能。综合神经逆控制思想,创建起神经滑模变自抗扰控制器,减少系统的抖振现象,实现对感应电机调速系统转速、转矩、磁链等参数的最优化控制。     

基于反电动势估计的异步电动机离散直接转矩控制方法

本文介绍了一种基于反电动势估计的异步电动机离散直接转矩控制方法（DTDTC），利用这种方法可以实现对电磁转矩和定子磁链模值的精确控制，在实现过程中，只需要知道少量的电动机参数一定子电阻和定子漏感，因而，这种控制方法对电动机参数变化具有较强的鲁捧性。另外，详细分析了计算延迟对系统性能的影响，在此基础上，对基本DTDTC控制方法进行了改进。最后，对这种控制方法进行了实验验证，实验试验结果表明了这种控制方法的有效性。     

基于Saber的异步电动机直接转矩控制系统仿真

为了验证基于三电平逆变器异步电动机直接转矩控制系统的可行性和有效性,利用Saber仿真软件优良的模块化和分级式的系统仿真能力,建立了异步电动机直接转矩控制系统中定子磁链与电磁转矩观测器、扇区判断、空间电压开关矢量表以及二极管箝位型三电平逆变器等子系统的仿真模型,并根据直接转矩控制原理最终构建了完整的系统仿真模型。利用所构建的系统仿真模型进行了仿真实验,仿真分析结果证明建立的系统模型是有效的,表明直接转矩控制系统具有良好的动态响应性能。     

Steady-state and transient performance evaluation of a DTC schemein the low speed range

In this paper, a direct flux and torque control scheme for industrial application is analyzed in order to emphasis the drive performance at standstill and in the low speed range. The control strategy utilizes the torque and rotor flux commands to determine the reference value of the stator flux. In order to improve the low speed performance a closed loop estimator is employed to evaluate the rotor flux. The validity of the control scheme is verified by simulations and experimental tests of an induction motor drive system     

Decoupling control for two-axis inertially stabilized platform based on an inverse system and internal model control

This paper describes a decoupling control scheme for a two-axis inertially stabilized platform (ISP) used in the airborne power line inspection system. The dynamic model of the ISP has been obtained by using the Newton–Euler equation first. The inverse system method combining with the internal model control has been proposed to deal with the nonlinearity and coupling of the ISP. The key idea is to design an inverse system with measured system states such as angular positions, rates and accelerations. Then a pseudo-linear system is constructed when the inverse system is connected with the original system in series. As a result, the coupled nonlinear MIMO (Multiple-Input Multiple-Output) system is converted to two linear decoupled SISO (Single-Input Single-Output) subsystems. Model uncertainties or unmeasurable disturbances existing objectively can be solved by introducing internal model control. Better decoupling effect and disturbance rejecting ability are demonstrated by numerical simulations and experiments carried out on a two-axis ISP system.     

无传感器交流传动技术的展望

在电机轴上无机械速度传感器的可控交流电机驱动，由于其低廉的价格和较高的可靠性，一直备受关注。为了取代传感器，它通过测量定子电流和电机端电压得到转子速度信息。矢量控制传动需要估计定子或转子磁通基波的大小和空间位置。为此需要使用开环估计器或闭环观测器，它们在准确性、鲁棒性以及对模型参数变化的敏感性等性能上均不相同。通过信号注入即利用电机的各向异性，可以获得零速范围附近的动态性能和稳态速度精度。本文使用复杂空间矢量的信号流程图来形象地描述交流电机无传感器的控制系统。     

An innovative direct self-control scheme for induction motor drives

The paper presents a new direct self-control (DSC) scheme for induction motor drives using the stator voltage third harmonic component in order to estimate the air-gap flux and the torque as well as to synchronize the supply voltage vector. Compared to previous DSC schemes the new one is independent from any motor parameter variation, specifically on stator resistance thus showing better performances at low speeds. The paper starts with a quick review on standard DSC main features pointing out the influence of stator resistance variations on the flux and torque control. The new DSC scheme is then introduced and evaluated by simulations and experimental tests on a 1.5 kW induction motor drive     

双馈风力发电机功率解耦控制的研究

介绍双馈风力发电机的基本原理,利用矢量控制并结合定子磁场定向的矢量控制,建立基于Matlab的双闭环控制系统仿真模型。为了更为准确地实现定子磁场定向并考虑到定子绕组电阻对磁场定向的影响,采用改进型的定予磁链观测模型。通过仿真验证了采用改进型定子磁场定向的双馈风力发电控制系统,实现了有功功率和无功功率解耦。     

Design and control of a permanent magnet spherical wheel motor

We present a permanent magnet–based spherical wheel motor that can be used in omnidirectional mobility applications. The proposed motor consists of a ball‐shaped rotor with a magnetic dipole and a hemispherical shell with circumferential air‐core coils attached to the outer surface acting as a stator. Based on the rotational symmetry of the rotor poles and stator coils, we are able to model the rotor poles and stator coils as dipoles. A simple physical model constructed based on a torque model enables fast numerical simulations of motor dynamics. Based on these numerical simulations, we test various control schemes that enable constant‐speed rotation along arbitrary axes with small rotational attitude error. Torque analysis reveals that the back electromotive force induced in the coils can be used to construct a control scheme that achieves the desired results. Numerical simulations of trajectories confirm that even without explicit methods for correcting the rotational attitude error, it is possible to drive the motor with a low attitude error (<5°) using the proposed control scheme.     

基于MRAS的永磁同步电机直接转矩控制系统的研究

研究了一种基于模型参考自适应无速度传感器的永磁同步电机直接转矩控制系统:将永磁同步电机的磁链模型作为参考模型,估算的定子磁链模型作为可调模型,设计了自适应定律对电机的转速与定子电阻同时进行跟踪辨识,使用空间电压矢量调制技术组成了永磁同步电机无速度传感器直接转矩控制系统。仿真实验结果表明该系统获得了近似圆形的定子磁链,在转速与转矩变化时均能准确的估算出电机转速,具有良好的动、静态性能。     

Digital control of induction motor current with deadbeat responseusing predictive state observer

For a high-power induction motor drive, the switching frequency of the inverter cannot become higher than one kilohertz, and such a switching frequency produces a large current ripple, which then produces torque ripple. To minimize the current ripple, a method based on deadbeat control theory for current regulation is proposed. The pulsewidth modulation (PWM) pattern is determined at every sampling instant based on stator current measurements, motor speed, current references, and rotor flux vector, which is predicted by a state observer with variable poles selection, so that the stator currents are controlled to be exactly equal to the reference currents at every sampling instant. The proposed method consists of two parts: (1) derivation of a deadbeat control and (2) construction of a state observer that predicts the rotor flux and the stator currents in the next sampling instant. This paper describes a theoretical analysis, computer simulations and experimental results     

基于SVPWM的永磁同步电动机直接转矩控制

针对永磁同步电动机直接转矩控制系统转矩和定子磁链脉动问题,采用电压空间矢量脉宽调制(SVPWM)的永磁同步电动机直接转矩控制方法。根据在每一个控制周期内,计算出参考磁链和所估计磁链的偏差,选择相邻非零矢量和零矢量,并精确地计算出各自的作用时间,然后利用线性组合法将其合成为新的电压矢量。仿真结果表明,所提出的控制方案是有效的,明显地改善转矩和磁链脉动,并且有很好的动态和稳态性能。     

Efficiency enhancement for indirect vector-controlled induction motor drive

In this paper, efficiency enhancement algorithms are developed and implemented on an indirect vector-controlled three-phase induction motor (IM) drive, and its performance under different operating conditions is analysed. The controllable electrical losses in the IM are minimised through the optimal control of direct axis (d-axis) stator current, and improvement in motor efficiency is achieved by weakening the rotor flux. The optimal d-axis stator current is also estimated using particle swarm optimisation (PSO) to validate the results obtained through analytical control method. The developed algorithms are tested under various operating conditions and the dynamic performance of the IM drive is analysed. The effectiveness of analytical and PSO-based efficiency optimisation control over conventional constant flux control, especially during light load at rated speed operation, is summarised. The effectiveness of the developed algorithm is validated experimentally through development of laboratory prototype set-up. The effect of parametric variation on efficiency, stator current, torque and speed of IM drive is studied through sensitivity analysis. The effect of variation in stator and rotor resistance due to change in operating temperature of the IM is also analysed and the robustness of the developed algorithm against parametric variations is demonstrated through simulation and experimental studies.