Control-Oriented Modeling of Single-Phase Transformers

Abstract

A control-oriented mathematical model for single-phase transformers, including the effects of saturation, hysteresis, and classical eddy current losses, is proposed. The model equations are derived by combining the mechanical and electrical properties of the ferromagnetic transformers’ core. This approach offers the flexibility for model enhancement by providing a procedure for incorporating additional domain-specific effects. It is shown that the model satisfies well-established properties of systems with hysteresis. The model is mathematically analyzed and experimentally validated on different transformers, confirming the applicability for a wide range of devices. Furthermore, it is demonstrated that the model structure is independent of any specific choice of the input signal form by reproducing experimental results for both sinusoidal and rectangular excitation voltages. The proposed model is compared with a single-phase transformer model based on the well-recognized Jiles-Atherton hysteresis model, which generally highlights the competitiveness in terms of accuracy and required computational effort for simulation studies. Therefore, the model is well suited for model-based controller design tasks and real-time applications.