Online calculation of transformer winding parameters

A model for calculating the turn ratio and leakage inductance of transformer winding is presented based on the equivalent loop equation of transformer,which takes the minimal error of loop equation as its optimization objective.The modern interior point method and the MATLAB programming are applied to solve its parameters.The method only needs the voltage and current information of transformer under normal operating condition,which is easy to implement because the winding structure and tap position are not involved.Various normal operating conditions are simulated by ATP simulation and the data of dynamic experiments are applied for verification,which shows that,not affected by the operating conditions and the unbalanced three-phase parameters of transformer,the proposed method has higher precision.