The Start-up Protection Configuration And Excitation System Design Of 1000MW Class Thermal Power Unit

With the rapid development of our country’s power industry and the continuous upgrading of power grid structure,the influence of large capacity power plants in the whole power system is becoming more and more serious,and the reliability of relay protection safe operation is challenged.The capacity of 1000 MW thermal power unit is large,so the safety of unit operation needs to reach a higher standard,so the protection device equipped should be more reliable.The excitation system can effectively maintain the generator terminal voltage,adjust reactive power and power factor,which plays an active role in improving the stability of power system operation and maintaining the reliable operation of the unit.For the newly-built thermal power units,the whole unit start-up is a necessary process for the design,manufacture,installation,commissioning and commissioning of the main engine and auxiliary equipment of the corresponding system in an all-round way.It is also an important way to ensure that the units can be put into operation stably and reliably and to create profits.Research on the important protection and excitation system of the whole unit start-up can continuously optimize the operation mode of the unit,which has good theoretical research value and engineering practice significance for maintaining the good production and operation state of the unit.This paper takes the 1000 MW thermal power unit of the second phase of a power plant as the control object,takes the safe and reliable operation of the unit as the primary principle,and combines with the working experience in the first and second phase of the power plant,puts forward the configuration scheme of the whole set of electric starting protection,and designs the realization of the excitation system.The main contents include: the configuration of generator transformer unit protection and 500 k V booster station bus protection,the design of phase II excitation system of power plant,and the test of electric whole set start-up.The internal and external faults of the generator are analyzed and the setting calculation of the generator protection is carried out.The regulation characteristics of the excitation regulator are discussed.Before the unit is put into operation,the possible fault interference in the operation of the unit shall be eliminated,so as to ensure the operation efficiency after the unit is put into operation.The manufacturer was entrusted to produce the corresponding protection device and excitation system equipment.The electrical test was carried out on the unit,the installed primary and secondary electrical equipment were checked and accepted,and the generator,main transformer,excitation system,synchronization device and other important equipment were tested.The test results show that the configured protection devices and electrical equipment can operate normally It runs well and meets the design requirements.After half a year’s trial operation,the results show that the electrical relay protection device and brush-less excitation system designed in this paper can ensure the safe,stable and reliable operation of 1000 MW thermal power units,and have the value of wide promotion.