Research On Digital Excitation Regulator Of Thermal Generator Set

As power capacity in our country is increasing and the power quality requirements of metallurgy,chemical industry and other important power users are improving,excitation control must ensure that the generator voltage and frequency vary within the scope of safety to guarantee the power supply quality.With the mature of digital control theory and technology and the dramatic improvement of computer and power electronics technology,digital excitation regulator ha s already been able to offer reliable and safe excitation power supply to synchronous generators.Based on the digital excitation regulator as the research object,this thesis mainly studied the following four aspects.First the hardware structure of adjuster is studied and an introduction is made on the design and composition of basic unit modules,such as analog module,control center,synchronous voltage plate,etc.through the design and analysis of each adjuster hardware function module,the hardware system of the adjuster is set up.Second also,focus on the components of the adjusting application program and deeply study on the program design such as main program and sampling program,etc.through the research of the adjust application program,the whole function of voltage regulation and fault protection of adjuster is realized.Third the principle of PID and PSS control and methods of parameter regulation and the typical link transfer function of excitation system are studied.Also,global function of excitation system is established,each link of the system and PSS model using Matlab/Simulink is stimulated.Finally the projects and standards of excitation system regulation in the static test,no-load test and the synchronization test are experimented recorded.The parameters of different stages of PID and PSS are adjusted by the test and comparisons.finally,the data and waveforms of digital excitation regulator obtained from the field test are analyzed.It is identified that the overall performance of the regulator meets the national standard and meets the requirements of field operation.Through the analysis of excitation regulator static and dynamic performance in this thesis,the technical personnel of power plant have obtained certain achievement in the engineering practice of the excitation regulator.