Research On Power System Stabilizer Which Adopt Global Signals

Conventional PSS can not damp low-frequency oscillation effectively due to localinformation and lack of capability of dynamic coordination.Using the concept ofinformation structure and coherent theorem, this paper arrives at the conclusion that addingremote information to decentralized excitation control can enhance the system damping andimprove system stability. With this conclusion and communication delay taken into account,PSS(GPSS) which feedback tie-line reactive power deviation, relative power angles and rotorspeeds of generators is designed with conventional PSS in service.After changing the designof the GPSS into problem of partial output feedback control and adjusting the weight matrixproperly, the method of minimum erratum excitation is applied to determine the controller'sparameters .Simulation of the IEEE 4-machine-11-node system show that GPSS cancoordinate with conventional PSS and the proposed control scheme can effectively damplow frequency oscillation. Finally, damping characteristics of PSS which adopt remotesignals are analyzed.