【作者】 李萍；

【导师】 蔡维由； 肖志怀；

【作者基本信息】 武汉大学 ， 水利水电工程， 2005， 硕士

【摘要】 当前我国在水电站的水轮机调节系统控制上采用的控制策略主要是PID控制,其控制参数都是基于一定的工况设计、试验得到的。因此它难以保证灯泡贯流式机组在单机带孤立负荷(特别是带大负荷)稳定运行,尤其是在工况变化较大时,稳定运行就更为困难,造成这种现象的主要原因是灯泡贯流式机组的工作水头低、水头的相对变化较大,从而使输出有功也波动较大。随着智能控制技术的出现,基于模糊逻辑、神经网络和遗传算法的智能控制策略也越来越多地应用到各工业领域中,水电机组调节系统控制也面临一个新的机遇与挑战。但目前,从某种程度上讲,彻底改变这种控制方式,建立并应用一种全新的控制策略目前尚处于研究探索阶段。因此,本文将CMAC神经网络和遗传算法分别与PID控制策略相结合,建立适合于灯泡贯流式水轮发电机组调速系统的智能控制器。 本文首先分析了我国水电开发的现状,论述了灯泡贯流式机组的技术优势、控制特点以及研究其控制策略的意义。接着简要介绍了水轮机调节系统控制技术的研究现状,并对各种控制策略进行了简单的分析。然后深入分析了灯泡贯流式机组的数学模型建立及模型简化,并在此基础上对常规PID控制进行MATLAB仿真。针对常规PID控制的不足,本文引入CMAC神经网络,建立了CMAC-PID复合控制器,实现了对灯泡贯流式机组的非线性控制,MATLAB仿真结果表明它比常规PID控制具有更好的动态性能。同时本文还分析了遗传算法的基本原理和特点,提出了基于遗传算法的PID控制参数优化,并应用于灯泡贯流式机组的控制,仿真结果表明,在频率扰动和负荷扰动上,它都有较好的动态品质。最后全面概括总结了本文的工作和研究成果,并指出有待进一步开展的工作。更多还原

【Abstract】 At present, PID control strategy is mostly used in Hydro-turbine regulating system. Its control parameters are gained through design and experiments according to the certain operating condition. So it is difficult to keep the stability of the bulb turbine units under isolated network condition. Particularly when operating condition changes largely, stability operation become more difficult. It is because that work head of bulb turbine units is low, the opposite varity of water head is big and turbine output power changes grequently. With the appearance of the intellectual control technology, the intellectral control strategies based on fuzzy logic, neural network and genetic algorithm is more and more applied to every industrial fields. So hydro-turbine regulating system control also faces new opportunity and challenge. Therefore, the paper establish two kinds of intellective controllers, which are fit for bulb turbine units regulating system, through respectively combining CMAC neural network and genetic algorithm with PID control strategy.This paper fistly recommends hydropower resources and status quo of hydropower development in China, and control characteristics and technology advantages of bulb turbine units, and the meaning of studying control strageties. Immediately, the study status quo of control technology of Hydro-turbine regulating system is briefly introduced, and various control strategies are analyzed. Then, The method to establish and simplify the mathematical model of bulb turbine units is analyzed in detail, and conventional PID controller is set up. Aim at the shortage of the conventional PID controller, the CMAC-PID is proposed. It is based on the conventional PID controller and combined with CMAC neural network. Simulation studies show the effectiveness and good performance. And then the basic principle and characteristic of the genetic algorithm is analyzed. Based on genetic algorithms, an optimization design of PID controller parameter is developed. The simulation results show that this method does not depend on the initial values of parameters and the optimal search efficiency is high. The end, all the work and research results are summarized and the shortage and further research work are pointed out.更多还原