The Research Of PSS Testing System Based On PC

PSS (Power system stabilizer) as an additional control device of excitation system,its function of inhibiting power system low frequency oscillation has been recognizedby people gradually. As control device to provide protection for the safe operation ofsystem, general test on the performance is crucial before putting into use. At present,traditional physical model testing method difficult to meet the need, an unknown deviceto be tested in actual unit is very dangerous. Therefore it is significant to build a set ofPSS test equipment which is simple and has perfect function.In order to complete the PSS performance test in the laboratory, PSS testing systemwhich based on PC is proposed and established by the author. First, PSS basic structureand working principle are introduced in this dissertation, the characteristics of singleinput power system stabilizer and double input the power system stabilizer arediscussed respectively, and the PSS input signals are analyzed in detail. According tothe analysis of PSS, single input PSS and double input PSS control unit analog circuitsare built by using electronic components on the basis of the existing parameters. Inorder to make testing results more close to the reality environment," a single-machineinfinite system" model is proposed, and using MATLAB to build " a single-machineinfinite system" model on PC, with the interface device to make data conversion andmatching between PC and external equipment, then by the method of ActiveX realizethe procedure call of Visual Basic to MATLAB, not only the " a single-machine infinitesystem" model data can exchange with outside, but also can control simulation modelon the Visual Basic man-machine interface, and test results also can be shown in theman-machine interface, reduce test work greatly. Finally the test system structure andparameters are checked, dynamic tests are made by connecting the PSS analog circuitand testing system, to analyze and verify test effects that the testing system on the PSSperformance.The test results show that PSS testing system which based on the PC has reasonablestructure, accurate parameters, can effectively simulate various faults of power systemand small perturbation, can test suppression effect of equipment on power system low frequency oscillation. And the system has friendly interface, simple operation, stableperformance, but also can be applied to the work of setting parameters of power systemstabilizer and so on.