Influence Of Turbine Generator Rotor Damping On Low Frequency Oscillation After Large Disturbance

The effect of turbine generator rotor damping has important significance on low frequency oscillation(LFO)after large disturbance.This thesis launched research on the influence of turbine generator rotor damping on low frequency oscillation after large disturbance.The main research contents is as follows:1.This thesis established the field circuit coupled Time-step Finite Element Model(T-S FEM)to study the influence of rotor damping on LFO,and studied the influence of each part structure of turbine generator rotor damping on LFO after large disturbance.The calculated results show that the damping effect of rotor wedge,rotor core and rotor gear bar was reduced when it acted alone.Damping structures have strong coupling effect when they collective action.The rotor wedge still played a major role and which made of aluminum alloy with large electrical conductivity has a better effect.2.This thesis comparative studied the different mechanism and effect between rotor damping system and PSS on LFO,proposed that rotor damping play a major role on amplitude in the initial phase,while PSS play a major role in the next stage.3.Studied the parameter design of PSS under the effect of the accurate rotor damping,and found the characteristics of PSS under the influences of rotor damping.The influence of material properties of rotor slot wedge and damping bars on PSS parameter setting was also studied.The optimal parameter value of PSS with different rotor damping structures and different material properties was found out.