Authors: K V Bharadwaj Karthik, V. Abhilash Naik, V Kowshik Chavali, G Suresh Babu
Abstract: This project focuses on the analysis of a three-phase star–delta step-down transformer using Altair Flux with emphasis on the no-load test and short- circuit test. The objective is to accurately evaluate core (iron) losses and copper (Joule) losses through finite element electromagnetic simulation. In the no-load test, rated voltage is applied to the primary winding while the secondary is kept open, enabling determination of magnetizing current, flux distribution, and core losses. The Bertotti loss model is employed within Altair Flux to separate hysteresis, eddy current, and excess losses in the core. Flux density distribution is examined to ensure operation below saturation limits. In the short-circuit test, the secondary winding is shorted and a reduced voltage is applied to circulate rated current, allowing evaluation of winding resistance, leakage reactance, and copper losses. The simulation accurately captures current density and I²R losses in both primary and secondary windings. The star–delta connection is properly modeled to obtain correct phase relationships and loss values. Results from Altair Flux demonstrate realistic loss estimation consistent with transformer theory. The study confirms that core losses remain nearly constant with load, while copper losses vary with the square of current. Overall, the work validates Altair Flux as an effective tool for detailed electromagnetic analysis of transformer performance using standard no-load and short-circuit test procedures.
