水轮发电机调速器的控制研究

发布时间：2018-04-01 19:36

本文选题：水轮机调速系统建模　切入点：模糊控制算法　出处：《河北科技大学》2014年硕士论文

【摘要】：近年来，我国的水电建设取得了突飞猛进的发展，然而因为发电过程中水轮机的负荷在不断发生变化，使其转速也随之变化，导致输出的电压和频率的不稳，不能满足用户的需要。因为发电机的输出频率是随着转速变化而变化，所以为了满足水轮发电机组并网输电频率指标要求，就需要对水轮发电机组进行速度控制。速度调节器在水轮发电机组并网发电系统中是一个核心控制单元，它通过对液压驱动装置—接力器的行程控制，实时对水轮机导叶开度的调节，达到对水力矩大小的调节，从而实现对水轮机组转速的控制使它保持在一定的范围内，最终实现电压和频率的稳定输出。本文首先根据水轮机调速系统的工作原理，把水轮机调节系统分成了几个模块，采用模块化建模设计，并依据模块间信号链接关系，建立了水轮机调节系统的线性化数学模型，可以看出水轮机调速系统是一个高阶的、非最小相位的复杂的动力系统，且存在参数时变性和非线性。针对水轮机调速系统模型存在的这些特性，调速器若采用传统的PID控制算法，通过甩负荷仿真和给定扰动仿真，发现调速系统难以满足性能指标要求比，为此在调速器控制模型中引入了模糊-PI控制算法。根据几种工况下的仿真和分析，并与PID控制算法进行了比较，结果表明模糊-PI控制算法在水轮机调速系统中具有很强的鲁棒性，，同时明显提高了系统的稳定性和快速性。
[Abstract]:In recent years, hydropower construction in China has made rapid progress. However, because of the constant change of turbine load in the process of power generation, the speed of turbine also changes, which leads to the instability of output voltage and frequency.Can not meet the needs of the user.Because the output frequency of generator varies with the change of rotational speed, it is necessary to control the speed of hydroelectric generator in order to meet the requirements of transmission frequency index.The speed regulator is a core control unit in the grid-connected power generation system of a hydro-generator set. By controlling the stroke of the hydraulic drive device and the relay, and adjusting the opening of the guide blade of the hydraulic turbine in real time, the speed regulator can adjust the size of the water torque.Thus, the speed of the turbine unit can be controlled in a certain range, and the steady output of voltage and frequency can be realized.In this paper, according to the working principle of hydraulic turbine governing system, the governing system of turbine is divided into several modules, and the linear mathematical model of the governing system of hydraulic turbine is established according to the signal link relationship between the modules.It can be seen that the hydraulic turbine governing system is a high order, non-minimum phase complex dynamic system with time-varying and nonlinear parameters.In view of these characteristics of the hydraulic turbine speed regulation system model, if the governor adopts the traditional PID control algorithm, through load rejection simulation and given disturbance simulation, it is found that the speed regulation system can not meet the performance requirement ratio.For this reason, fuzzy-Pi control algorithm is introduced into the governor control model.According to the simulation and analysis under several operating conditions, and compared with the PID control algorithm, the results show that the fuzzy Pi control algorithm has strong robustness in the hydraulic turbine speed regulation system, and obviously improves the stability and rapidity of the system.
【学位授予单位】：河北科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV734.4

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