An efficient method to calculate power transformers’ frequency response from a state-space model

Frequency response analysis of power transformers and reactors can reveal mechanical and electrical defects in windings’ structure. Interpretation of a response though, is not an easy task for inexperienced engineers. Furthermore, an in-depth study of windings’ failure requires either practical, physical or mathematical models. Building complex circuits to model the power transformers’ frequency response is tedious; that is where state-space modeling comes in handy. The main problem is that the state-space model requires symbolic calculations, which are not always feasible on low-end computers. This paper shall introduce a symbolic-free method to calculate the transfer function of power transformers and reactors from their state-space model.