Abstract:The accuracy and reliability of the equipment parameters of power network is very important for the analysis and calculation of power system. However, the parameters of power equipment in actual operation are not fixed constants, and they will change according to the changes of environment and actual operation conditions. And it''s hard to measure directly and replace it with the correct value. As the hub equipment of power transmission, the accuracy of operation parameters of transformer is more important to the analysis of power safety and stability. In order to accurately reflect the real parameters of transformer in real operation, this paper presents a method for estimating transformer operating parameters based on power big data density clustering analysis technology, on the basis of establishing the transformer parameter equivalent model based on Γ type equivalence. The parameters of transformer equipment are estimated by using the measured data of SCADA system after bad data identification. Finally, the actual operating parameters of the equipment within a certain allowable error range are obtained. Taking a transformer in Xuzhou Power Grid as an example, by clustering and fitting the data of SCADA system, the results show that the method is effective and practical in engineering.