Analysis and Extension of the Canonical Model applied to DC-DC converters with Input Filter and Output Post-filter

Sometimes a post-filter is implemented at the output of the converter, as there are applications that require a very low output voltage ripple or output current ripple. On the other hand, the use of an LC filter at the input of the converter is implemented with the aim of reducing electromagnetic interference or due to special specifications. As it is well known the implementation of both filters affect the dynamics of the system, therefore it is important to have the transfer functions that consider the effect of both filters in order to have an optimal design of the compensator and guarantee the stability of the system. In the existing literature, the effects of the input filter and post-filter have been addressed separately, the main objective of this paper is to analyze the dynamics of the system and extend the canonical model in order to obtain general transfer functions such as control to output voltage that involve the effect of both filters and even considering the feedforward of output current and input voltage. The phase-shifted full-bridge converter has been selected in order to validate the control to output voltage transfer function in an experimental and simulated way.