Frequency response of contactless transformer using T and Pi model

Compensation circuits are used in contactless power transfer systems used in Light Rail Systems to work in resonance with inner inductances of the contactless transformer to maximize the power transfer. The presence of misalignment makes the circuit to operate outside the resonance point. One way of make the operation to resonance again is change the switching frequency. To study deeply this effect the frequency response of contactless transformer is modeled as T and a Pi equivalent circuit for the most common compensation sets. The transfer functions are calculated, the Bode diagrams are constructed and the results are compared with the measuring on a prototype.