Multi-degree-of-freedom optimal control method for four-switch Buck-Boost converter

The invention discloses a multi-degree-of-freedom optimal control method for a four-switch Buck-Boost converter, and belongs to the technical field of power conversion in a power electronic technology. In the prior art, a traditional mode switching control method has the problems of switching point discontinuity, gain nonlinearity, soft switching incapability and the like. Some novel control methods proposed in recent years can realize soft switching, but need to record a large number of multi-dimensional data tables, and depend on a hardware current sensor dedicated to zero voltage switching (ZVS) current detection. The invention provides a multi-degree-of-freedom optimal control method for a four-switch Buck-Boost converter, and the method comprises the steps: achieving the zero-voltage switching of all switching tubes, taking a minimum inductive current average value as a constraint, taking a minimum inductive current root-mean-square value as a target function, and carrying out the optimal control of the