【作者】 吴翼；

【导师】 黄辉先；

【作者基本信息】 湘潭大学 ， 电力电子与电力传动， 2006， 硕士

【摘要】 滑模变结构控制是一种非线性控制方法,由于其滑动模态对外部摄动及内部参数的变化具有很强的鲁棒性,因此应用十分广泛。但是该性能是在系统状态到达滑模面上才得到,在系统趋近运动阶段,系统控制只是一般的反馈控制,系统此时对外部的干扰和内部参数的变化缺乏自适应性,因此在很大程度上影响了滑模变结构的鲁棒性。针对存在内部参数变化和外部干扰的非线性系统,本文研究了一种强鲁棒控制方法。该方法结合时变滑模变结构控制和智能模糊控制二者的优点,不仅使系统任意初始状态都处于滑模面上,具有全局鲁棒性,而且抗干扰能力大大增强。论文最后给出的仿真实例表明该控制方法行之有效。异步电机的直接转矩控制系统以其思路新颖、控制方案简单及性能优越等特点受到人们的普遍重视。本文对异步电机的数学模型进行详细研究,并构建了直接转矩控制仿真系统,对直接转矩控制方法的特点及其存在的问题进行深入的理论和仿真研究。作为一种高性能的交流调速系统,在直接转矩控制系统中,速度调节器通常都采用PI调节器,使得系统的快速性和抗干扰能力及对系统参数扰动的鲁棒性不够理想。本文设计了一个基于滑模变结构控制的速度调节器,使得系统具有更好的鲁棒性和动、静态性能。仿真结果表明该方法的可行性。更多还原

【Abstract】 Variable structure control with sliding mode is a kind of nonlinear control method, which is used quite widely now as its sliding mode is of global robustness against parameter variations and external disturbance, but this characteristic can’t obtained when the system is out of the sliding mode. So in the reaching mode step, it is lack of robustness for the system is controlled only by feedback control, as a result, the robustness of sliding mode control is influenced strongly.A new fuzzy time-varying sliding mode control method for a class of nonlinear systems with uncertainties is presented. It combines the advantages of fuzzy control and sliding mode control, as a result, the system is of global robustness against parameter variations and external disturbance as the state lies on the sliding surface from any arbitrary initial states, and the performance is much better improved. Computer simulation results show it is correct and efficient.Direct torque control (DTC) system for induction motor has got wide attention with the advantages such as its new thoughts, simple control scheme and excellent performance. In this thesis the author made a study of asynchronous motor model, designed a hybrid simulation system of DTC and analyzed the characteristics of the DTC system and the existing problems detailedly.The DTC system is a high-performance AC driving system. But conventional speed controller in DTC system is PI adjuster, which can’t make the system have enough quick response, the ability to restrict the noise and strong robustness to the parameters of the system. So the author designed a speed regulator based on sliding-mode control theory, which make the system has strong robustness to the parameters, excellent dynamic and steady-state performance. Simulation results show the method is effective.更多还原