Calibration of a Three-Phase Transformer Simulation Model Based on Experimental Voltage and No-Load Current Waveforms

A method for calibrating a simulation model of a three-phase transformer with a bar-shaped magnetic circuit based on experimental current and voltage waveforms is proposed, which makes it possible to reproduce the type of phase current waveforms in the steady-state idle mode with an increased reliability. The calibrated model can be used as a digital twin of a real transformer, including the use for diagnosing damage to the magnetic system of the facility without disassembling it. The algorithm proposed for model calibration is based on genetic algorithms for solving a system of nonlinear equations for the calculation of the magnetization curves for the elements of the transformer magnetic system. The algorithm is implemented in an environment of the MATLAB Simulink software package using a SimPowerSystems library. The comparison of the simulation results with experimental data has shown that the calibrated models reproduce the pattern of current and voltage changes in a much more reliable way than all the known models do. In particular, the average deviation of the calculated curves from the experimental current waveforms does not exceed 10%.