【作者】 吴峻；

【导师】 李圣怡；

【作者基本信息】 中国人民解放军国防科学技术大学 ， 机械电子工程， 2000， 博士

【摘要】 随着电力电子技术、计算机技术的发展，交流电机控制技术有了很大的发展，已经逐渐替代传统的直流传动技术，应用在国民经济的许多领域。现今的交流电机控制技术主要朝着数字化、智能化、集成化的方向发展，集中在磁场定向控制(FOC)、直接转矩控制(DTC)以及空间电压矢量PWM (SVPWM)等方面的研究展开。DTC作为近年来发展的一种新型的控制技术，成为了交流电机控制领域的研究热点，本文的研究就是针对鼠笼电机转矩控制以及电动车驱动控制的技术而系统地展开的。 首先，通过大量的文献综述，归纳总结了交流电机控制和电动车交流驱动控制技术的发展现状、方向以及存在的问题，认为FOC、DTC以及SVPWM各自都存在优缺点，在最终解决交流电机实现线性控制特性的问题上它们必须相互融合，取长补短，而且在这些方法中磁链观测是非常重要的一项。 然后，通过对DTC系统进行数学分析和实验研究，归纳了DTC的特点，分析了磁链模型中参数变化的影响。为了改善DTC系统的低速特性，提出了相位校正转矩控制法(PT-DTC)，保留了U-I模型结构简单的优点，同时改善了低速特性。根据前面的分析和实验，结合Lyapnov稳定性原理、系统传函的零极点的方法进一步对DTC系统的稳定性进行分析，认为在低速段状态观测的渐进稳定性是影响系统稳定的主要因素。 为了改善DTC的控制特性，在分析电压矢量对磁链和转矩的控制效果的基础上，结合SVPWM提出一种改进型矢量转矩控制法——IVTC，改进了磁链的低速模型，明确了电机转矩、磁链和电压矢量之间函数关系，丰富了控制手段，提高了控制特性，适宜工程实现。在进行该研究的过程中，提出一种简化的DFC-PWM法，能够有效改善输出转矩的性能；同时就电机参数的辨识也提出了一种NIM法，它利用最小二乘原理，简化了电机模型，在运算中设计滤波器简化了数据处理，保证了方法的可靠性和简单性。 在电动车的交流驱动控制技术应用上，除了前面的电机控制技术外，主要分析了再生制动的状态，设计了一种转差控制的再生制动控制RBSRC；在分析零矢量限流性能的基础上提出了一种新型的限流模式，保证了系统运行的可靠性；为提高电池低压下电机的输出转矩，设计了两种模式的过调制，提高了电压的利用效率。 最后应用以上研究结果，在国防预研专项资金的支持下，设计完成了GREEN SCIENCE电动实验车一辆。更多还原

【Abstract】 With development of power electronics and microprocessors, AC drives have been improved greatly, which are steadily taking the place of DC drives in traditional fields. It is now developing towards digital, intelligent and integrated implementation, which is focused on field orient control (FOC), direct torque control (DTC) and space vector pulse width modulation (SVPWM) etc. Since DTC is a newly developed method, recently it is an important and challenging area in the field of AC drives. In this thesis, attention is focused on DTC of squirrel cage motors and electric vehicles (EV) driven by AC motors.Based on an overall review of related papers, the state of the arts and development trends of AC drives and EV’s AC drives are summarized. Since there are some disadvantages among FOC, DTC and SVPWM, it is necessary to mix all these methods and syntheses them to achieve linear characteristics. And observation of the stator flux is the most important one for AC drives.After analysis and experiments on DTC system, the disadvantages of DTC are summarized. Also sensitivities between parameters and control character are analyzed based on each type of flux model. In the end of this part, a DTC method with phase tuned (PT-DTC) is proposed to improve character at low speed and its feasibility is proved by experiments.Based upon analysis and experiments in the fore part, stabilities of DTC systems are further discussed using Lyapunov theory, zero and pole method of transfer function of AC systems. It is very important that stability of observation for stator flux and current has serious effect for vibration at low speed.To improve DTC system, an improved method of vector torque control (IVTC), based on analysis of effects between vectors and variations of flux and torque, is proposed which utilizes an improved flux model at low speed. Since it sets up a function, it is possible for researchers to use more kinds of strategies to control flux and magnetic torque respectively in DTC systems. During the research, a simple PWM method with direct flux control (DFC-PWM) and a novel identification method (NIM) for parameters using least square theory are proposed. Filter is designed to simplex calculations without decreasing correctness of results.For EV application, except traction methods for AC drives above, some new schemes are discussed. After analysis the state of regenerative brake, a new regenerative brake method of slip ratio control (RBSRC) is presented here. Since zero vector can not limit currents allthe time in the experiments, a new current limit mode is introduced. For utilization of the batteries, a method for over modulation with two novel modes is analyzed and realized in EV system.Finaly, a prototype of test vehicle, namely GREENSCIENCE, is designed for the application of these methods. In the appendix of this thesis some specified papers and photos are introduced also.更多还原