State plane approach to frequency response of resonant convertors

The steady state response of a resonant convertor can be represented graphically by the state plane diagram. On using the perturbation method on the steady state trajectory, a discrete small signal model for the convertor can be derived from the input voltage, controlled switching frequency and state variable perturbations. The conventional series resonant convertor is used as an example to demonstrate an analytical approach. However, this method of analysis can be applied to resonant convertors in general. From the small signal model derived, the frequency response of the convertor can be calculated.