A model power transformer in labs or simulation software represents the behavior of real transformers, including magnetizing inductance, leakage reactance, losses, and saturation effects. It allows students and engineers to study voltage regulation, short-circuit behavior, inrush currents, and harmonic responses without risking large equipment. Physical scale models may demonstrate core construction and winding configurations, while mathematical models are used in power system studies, relay coordination, and transient stability analyses of complex grids.