【作者】 方红庆；

【导师】 沈祖诒；

【作者基本信息】 河海大学 ， 水利水电工程， 2005， 博士

【摘要】 水轮机调节系统是一个集水力、机械、电气为一体的,具有非最小相位、非线性、时变特性的复杂的非线性控制系统。为了要满足水轮机调节系统静态和动态性能的要求,需要研究具有较高可靠性、稳定性的水轮发电机组控制非线性策略。而且,还需要对实现该控制策略工程应用的相关技术进行研究。 本文的主要内容及创新点如下: 1.提出了一种将一个非仿射型的非线性控制系统构造成仿射型的非线性控制系统的方法:即对其基于某个特定工况点做近似的处理,进而把原非线性系统构造成仿射型的非线性控制系统。这样,就可以进一步利用非线性系统控制理论的相关方法设计其非线性控制规律。 2.依据微分几何非线性控制理论中输出对扰动解耦的控制算法,设计了水力机组非线性状态反馈控制规律,该控制规律能够反映水轮机调节系统的时变、非线性特性并考虑了有压引水管道水流惯性的不利影响。所有的控制变量都是当地可测变量,与电网的参数无关。 3.提出了一种新的改进的粒子群优化算法,并以水轮机转速偏差的加权ITAE指标作为改进粒子群优化算法的适应度函数。计算结果表明,改进粒子群优化算法无论是对水力机组非线性控制策略还是对水轮机常规PID控制规律都是一种简单有效的参数优化方法。 4.使用Simulink支持的S函数格式,用MATLAB语言编制描述水轮机传递系数时变、非线性特性的程序,构成S函数模块供Simulink调用。建立了MATLAB/Simulink软件环境下的具有时变水轮机传递系数的水轮机调节系统动态非线性计算机仿真模型,并以此模型为基础,建立了水力机组非线性控制策略计算机仿真模型。基于该仿真模型的计算机对比仿真实验的结果表明水力机组非线性控制策略具有较好的控制性能。 5.将水力机组非线性控制策略移植到高性能32位可编程计算机控制器PCC中,成功研制了具有非线性控制功能的水轮机数字调节器实验室装置。同时,本文利用基于PCC的水轮机调节系统动态实时仿真仪与安装了水力机组非线性控制规律的水轮机数字调节器组成闭环回路进行对接仿真实验,实验结果也验证了水力机组非线性控制策略的有效性。更多还原

【Abstract】 Hydraulic turbine regulating system is a complex nonlinear control system, which has non-minimum-phase characteristic and time varying parameters. Hydrodynamics and mechano-electric dynamics are all involved in such a nonlinear dynamic system. To satisfy the static and dynamic requirements, it is necessary to research the hydraulic turbine generating unit nonlinear control strategy with higher reliability and robustness. And the industrial application research of such a nonlinear control law also should be performed.These main contributions of this diesis are:1. Presented a method to change a non-affine nonlinear system to an affine nonlinear system, which approximately processes the original system on a specified operating point. Then, the relative approach of nonlinear control theory could be applied to design the nonlinear control law for the original system.2. Developed the mathematical model of hydraulic turbine regulating system with a Fransis turbine, single pressure water supply system and isolated operation condition. The hydraulic turbine generating unit nonlinear control strategy was designed based on disturbance-decoupling method of differential geometric nonlinear control theory. The hydraulic turbine generating unit nonlinear control strategy could adapt these dynamic hydraulic turbine transfer coefficients and attenuate the no-elastic water hammer effect in penstock. All these control variables are local measurements and are independent to electrical power supply system.3. An improved particle swarm optimization (PSO) algorithm was designed. And a weighted ITAE index of turbine speed error was taken as the fitness function of the improved PSO algorithm. The computer simulation results indicate that the application of the improved PSO algorithm for hydraulic turbine nonlinean control strategy parameters or PHD gains tuning is effective.4. These simulation models were developed in the MATLAB/Simulink-based software environment with S-function. These S-function based simulation models of hydraulic turbine transfer coefficients are all dynamic and time varying. Then, the dynamic and digital simulation model for the hydraulic turbine generating unit nonlinear control strategy was developed. The digital simulation results indicate that the hydraulic turbine generating unit nonlinear control strategy can improve the dynamic performance in hydraulic transients.5. The software of the hydraulic turbine generating unit nonlinear control strategy was developed. And then based on a 32-bit programmable computer controller (PCC), the digital controller with the hydrauli(?) turbine generating unit nonlinear control strategy was developed and connected to a 32-bit PCC-basec dynamic real-time simulator for hydraulic turbine regulating system. A closed-loop test was performed and the result also indicates that the hydraulic turbine generating unit nonlinear control strategy has a good performance for hydraulic turbine regulating system.更多还原