【作者】 巫庆辉；

【导师】 邵诚；

【作者基本信息】 大连理工大学 ， 控制理论与控制工程， 2006， 博士

【摘要】 近年来，现代电力电子技术、微处理器技术及现代控制理论的发展，为高性能电机控制技术的发展提供了重要物质保证。同时，随着生产工艺技术及现代自动化装备水平的发展对电机驱动系统稳态性能及动态性能提出了更苛刻的要求。直接转矩控制技术与矢量控制技术同属于交流调速领域的高性能变频调速技术，目前，在该领域得到了深入地研究。尤其，直接转矩控制以其结构简单、强鲁棒性与快速性等特点受到了世界各国变频调速领域企业及科研院所更为普遍的关注，并且该技术已经成功地应用于大功率交流电机驱动系统。然而直接转矩控制技术以容差形式的Bang-Bang控制模式给系统的稳态运行带来了转矩脉动大、电流谐波成分重、定子磁链轨迹畸变等严重问题，大大限制了其应用领域，这一点已经成为传统直接转矩控制技术不可逾越的缺陷。如果将矢量控制技术与直接转矩控制技术融合，提出新的直接转矩控制理论，将会是解决此问题的最好出路。另外，对于一个高性能的速度闭环控制系统来说，速度反馈信号是必须的。无速度传感器技术对于降低系统成本，提高系统可靠性都具有非常重要的意义，并已经成为变频调速领域研究的热点问题。 为此，本文以三相感应电机无速度传感器直接转矩控制中存在的问题展开了理论与应用研究，主要工作如下。 1、针对传统直接转矩控制技术所固有的稳态运行时转矩、磁链、电流脉动大的问题，提出了一种利用转矩误差与磁链误差、通过滑模变结构控制方法实现对转矩与磁链进行控制的新的直接转矩控制方案，分别以转矩误差与磁链误差作为状态变量设计了时变积分型滑模平面，保证了趋近过程的系统状态保持在滑模面附近，减小了趋近距离，不仅提高了系统的鲁棒性，而且保证了滑模运动具有良好的动态品质；针对滑模变结构控制本身的抖振问题，提出了一种通过滞环比较器实现滑模变结构控制与传统PI控制的平滑过渡的混合滑模变结构控制方法，既能发挥滑模变结构控制的鲁棒性与快速性，又能发挥传统PI控制的平滑特性，削弱了系统的抖振。 2、针对传统伺服驱动系统的位置与速度外环PI控制的结构复杂、双闭环耦合及对参数等不确定性扰动鲁棒性差的问题，在直接转矩控制理论将电机的转矩与磁链解耦的基础上提出了基于动态神经网络的自适应控制方案，简化了控制系统结构，提高了系统对参数变化的鲁棒性，改善了伺服控制系统的动态及稳态性能。 3、基于电压模型的传统定子磁链估计方法具有开环积分的特点，直流偏置、初始值及噪声在实际应用中常常会导致积分饱和，低通滤波器代替纯积分器虽然能够解决积更多还原

【Abstract】 In the last few years, the development of the technique of modern Electric Power and Electronics, Micro-processor, and Advanced Control provides very important pledge for high-performance control of motor. At the same time, with the development of the technique of production and the level of modern automation equipment, favorable stable-state and dynamic-state performance for the drive system of motor is wanted. The Direct Torque Control (DTC) technique and the Vector Control (VC) technique, which belong to high performance variable-frequency adjusting-speed technique in the AC drives, are both researched widely. Especially, DTC is very popular to the entire world because of its fast behavior, simple structure, and robustness. And DTC technology has successfully been applied in high-power ac drives. However, Bang-Bang control mode of classic DTC introduces extra electromagnetic torque chattering, stator flux ripples, and current harmonics, which has become its inherent disadvantages and confined the DTC technique to be applied widely. It is the best method to solve the above questions that a novel DTC theory is founded by synthesizing VC. Moreover, for high-performance speed close-loop system, the feedback of speed is wanted. Speed-sensorless technique is very important to reduce its cost and strengthen its reliability, and has become the focus of AC adjusting-speed field.So, this dissertation develops theoretic and application research on the problems of speed-sensorless DTC of induction motor. Its main works are followed as:1、 For its inherent drawbacks of classic DTC, such as torque, flux, and current ripple, a novel DTC scheme is presented, in which a sliding mode variable structure control (SMVSC) method is applied to control electromagnetic torque and stator flux by using torque and flux errors. In order to preserve the system states near the sliding-mode surface and reduce the reaching distance, a time-variable integral sliding-mode surface is devised, which not only improves the system’s robustness, but also guarantees good dynamic quality of the sliding-mode states. For its intrinsic chattering of SMVSC, this dissertation suggests a hybrid sliding-mode variable structure control (HSMVSC) method, in which VSC can smoothly transit to classic PI control by hysteresis comparator, taking advantage of the best features of linear control, smooth operation, and of VSC, quickness and robustness to perturbations, resulting in reducing the chattering.更多还原