Abstract: Matlab’s high-efficient matrix calculation ability makes it possible to realize power flow analysis simplified. The author makes use of m-file to write differential action of transformer, then makes use of Matlab interface technology ,and to combine with the advantage of friendly and convenient on VB.To bring up a differential action protection analysis programs be blend-writed base on MATLAB and VB ,to expect to provide consultation with the fault simulation of the power system.
Based on an actual simulation model of power transmission system , using the Active X technology , this paper process a method which can be used to implement data change between Matlab and VB.First ,we build a simulation model which conclude 220kV transmission line power system ,brake on ratio of differential action of transformer and twice harmonic waves to brake protection device .Then we simulate the single phase to ground permanent fault and single phase to ground instant fault in the model to get three phase voltage and current simulation waveforms and the protection operation waveform. Finally we show the simulation results on the Visual Basic software’s interface.
Two new methods processed in this paper integrate the advantages of Matlab and VB for the design and using of simulation software.
Keywords: Matlab ; VB ;differential action of transformer;simulation ;protective relays