The Research On Compound Control For Turbine Governor And Excitation System Of Hydroelectric Generating Unit

The main task of the control system of hydroelectric generating unit is to control the speed(frequency)and the active power,the control of terminal voltage and the reactive power of the generator,ect.These tasks are controlled by the separated design of the turbine regulating system and the generator excitation system.But in fact,in the dynamic process of the control system,the change of the speed and the voltage of the generator is mutually influenced,coupling relationship exists between the two,so in order to guarantee optimal control of the entire system target,the two sub control system need for compound coordinated control,not simply as a stand-alone system performance optimal to controller design,but to carry on the design according to the overall system performance is the best.Therefore,in this paper,based on the traditional control of the turbine generator unit,the use of the decoupling theory,the hydrogenerator unit to carry out compound research.Firstly,according to the working mechanism of the turbine and generator,established the mathematical model of the speed regulating system and the excitation system respectively.Secondly,because the control system of hydroelectric generating unit is a water,machine,electric coupling system,starting from the traditional control,studying their mutual coordination,and on this basis,considering the relationship between the speed control system and the excitation system,a compound control model based on the traditional control is established.In order to make the coordination control of the objects,designed the decoupling controller using the inverse Nyquist array method of the multivariable frequency control theory.Finally,in the MATLAB environment,established the simulation platform,made comprehensive control objects and the designed controller models and simulink experiments using simulink model library toolbox.Then compared and analyzed the results in the simulation of using the simulation of decoupling controller and the simulation of using PID control system.Simulation results show that when the hydraulic turbine governing and excitation compound control is enable to inhibitory effect of speed regulating system and excitating system,make the control system fast and stable,in a certain extent,improve the control system dynamic quality.