Research on online monitoring of transformer winding deformation state based on short circuit reactance

For monitoring deformation state of transformer winding, the online monitoring method based on short circuit reactance is researched in this paper. The mathematic model of short circuit reactance is established, and online calculation method is researched. Simulation model of short circuit reactance is built based on MATLAB. The online test system of short circuit reactance is designed. Aiming at a type S-11-M-500/35 transformer, three fault types windings which include winding loosing, low voltage winding compression/high voltage winding tension and winding folding are designed. The online monitoring experiment is made. Experimental results indicate that change rates of short circuit reactance of three fault types windings are 5.61%, 3.18% and 7.27%, which calibrates the availability of the monitoring method.