【作者】 王永；

【导师】 肖仁山；

【作者基本信息】 广西大学 ， 控制理论与控制工程， 2003， 硕士

【摘要】 本文的主要研究内容是：将模糊滑模变结构理论应用于静止无功补偿器的控制之中。电力系统具有强非线性和结构工况多变的特点，因而对这样的系统实现有效控制是极为困难的。而滑模变结构控制理论上具有对加于系统的摄动和干扰很强的鲁棒性，并具有很好的动态性能，因此，将滑模变结构理论应用于电力系统的控制是可行的。另外，静止无功补偿器在电力系统中已得到广泛应用，不少文献已经证明它不仅可以维持装设点电压的稳定，而且在提高系统的稳定性方面也有良好的作用，因此，本文为静止无功补偿器设计了以改善系统功角稳定为目标的模糊滑模控制器。 首先，本文建立了装设有静止无功补偿器的单机无穷大系统的数学模型。由于该模型是非线性的，因此本文采用反馈线性化的方法得到了系统的线性化数学模型。然后基于该线性化数学模型再设计以改善系统功角稳定为目标的模糊滑模变结构控制器。 其次，抖振问题是影响滑模变结构控制广泛应用的主要障碍。因此本文在滑模变结构控制的基础上引入了模糊控制，设计了模糊滑模变结构控制器。综合了模糊控制和滑模变结构控制各自的优点，以削弱变结构系统的抖振。为了改善模糊控制的性能，本文还对模糊控制进行分级处理。 电力系统经常受到外界干扰的影响。本系统的干扰不满足扰动与系统的完全匹配条件，因此滑模控制系统的滑动模态将受到扰动的影响。为了使系统能够有效抑制外界的干扰，本文将H∞鲁棒控制理论引入到滑模控制系统的滑模面的设计中，并得到了对不匹配干扰具有较强鲁棒性的模糊滑模控制器。 最后，为了验证了文中算法的有效性，本文利用MATLAB／SIMULINK及其工具箱对系统进行了仿真。仿真结果表明：静止无功补偿器的模糊滑模控制器不但设计和实现简单，而且效果优良；所设计的SVC控制器可以显著地改善系统的功角稳定；H∞模糊滑模控制器的抗扰性能优于一般的模糊滑模控制器，同时由于模糊控制的引入，削弱了滑模变结构系统的抖振现象。更多还原

【Abstract】 This paper demonstrates a fuzzy sliding mode control (FSMC) scheme for static VAR compensator (SVC). Strong nonlinearity and changeability of the configuration and operating point are two characteristics of the power system. So it is very difficult to be well controlled. The sliding mode control system is insensitive to the system parameter variations and external disturbances, and it can obtain invariant dynamics and steady-state response in ideal case, so it is feasible to use the sliding mode control for the power system. Now that SVC has been used widely in the power system and some literature states that SVC can not only maintain voltage stability but also effectively improve the power angle stability, the FSMC controller for SVC to improve the power angle stability is designed in this paper.First of all, a nonlinear model for a single-machine infinite-bus system with static VAR compensator is established. Based on the input-output feedback linearization technology, the nonlinear model is converted into a linear model. Then the fuzzy sliding mode control strategy is proposed to improve the power angle stability of the system.The chattering problem is the main obstacle to use the sliding mode control widely. In order to attenuate this phenomenon, the fuzzy logic theory is introduced in the design of the variable structure controller, and a sliding mode variable structure controller is designed which combine the advantages of both fuzzy control and sliding mode variable structure control. In addition, a new fuzzy control by different levels is proposed to improve the performance.Furthermore, the power system is often influenced by disturbance. The disturbance in our system doesn’t satisfy the matching condition, so the performance of sliding mode control system is affected by the mismatching disturbance. This paper introduces H∞ robust control theory to design thesliding manifold of the variable structure control system. Thus, another fuzzy sliding mode controller that can attenuate mismatching disturbance is obtained.Finally, The proposed algorithms are verified by simulation using MATLAB/SIMULINK and its toolboxes. The results show that the fuzzy sliding mode controller is rather simple and yet quite efficient, that the power angle stability of the power system is obviously improved by the control system of SVC , and that the advantages of H∞ fuzzy sliding mode control are obvious in comparison with the ordinary fuzzy sliding mode control in attenuating mismatching disturbance and H∞ sliding mode control in reducing chattering.更多还原