Experimental Research On Capacity Increasing And Transformation Of Excitation System In 300MW Power Plant

At present,with the further deepening of china's power system reform,traditional coal-fired power generation enterprises must maintain a leading position in the increasingly fierce competition in the power generation market.It is necessary to objectively and comprehensively analyze the system energy consumption sources of power plants and apply contemporary advanced technology to increase the capacity of major main and auxiliary engines.They must complete energy-saving and consumption-reducing transformation,digging the energy-saving and consumption-reducing potential of the unit.They should improve the output of the unit,and reduce the coal consumption level of the steam turbine generator set and production costs to improve economic benefits.Among them,the expansion of existing generator sets is one of the important means.In order to improve the efficiency of the unit and increase the competitiveness of the unit,Zhanjiang Power Plant will increase the capacity of the 4*300MW generator and transformer system,and increase the rated load of the turbo generator from 300 MW to 330 MW.Correspondingly,the excitation system is expanded.Firstly,according to the changing parameters of generator and main transformer capacity,the excitation system will be designed and calculated.The thyristor rectifier and the de-excitation switch as well as the upgraded excitation regulator and other equipment will be replaced,and are used to demonstrate the reliability of the excitation system.Secondly,the parameter identification and modeling test of excitation system after the capacity of the system is expended are introduced in detail.In the parameter identification of the excitation system model,the following experiments are done: No-load step response tests,no-load characteristic measurement,parameter identification of excitation regulator model.The result shows that the dynamic performance of the excitation system is good.Based on the results of this experiment,the parameters of generator and excitation system are calculated.Therefore,the simulation model of the no-load step response of the excitation control system is established.Based on the comparison between the no-load step response in fact and the simulation results,the accuracy of parameters of excitation control system is verified.Based on parameter identification of excitation system model,the model and parameters of excitation system are established,leading to provide the basis for calculation and analysis of stability of power plant.Finally,being certificated by the on-site setting and commissioning test of the generator set PSS,the PSS which is designed can increase the damping ratio and suppress theoscillation effect and it can play an important role in increasing the anti-interference performance of the generators,improving the stability of the power grid,controlling the weak damping oscillation associated with the generators and so on.At present,the experience of capacity expansion and transformation of the 300 MW unit has less experience.The transformation of the generator group system of the #1 unit of the Zhanjiang Power Plant has been successfully completed and put into operation,and no faults and abnormal conditions have occurred,which proves that the transformation plan of this paper is feasible.It has certain guidance and reference for the capacity expansion of similar units.