Much effort has been made to the switching surface control of buck converter. However, it
remains a fundamental challenge to apply the same concepts and associated control techniques
to converters with non-minimum-phase characteristics. A nonlinear control method for all basic
DC-DC converters (ie buck converter, boost converter, buck-boost converter, C’ uk converter and
SEPIC) is proposed by deriving a uniform switching surface. It retains the advantages of boundary
control for buck converter with second-order switching surface. For example, the converters can
reach steady state in two switching actions after being subjected to large-signal disturbances. The
derivations are general-oriented and can determine the circuit variables needed in the switching
function. The same controller is universally applicable to different converters operating in both
continuous conduction and discontinuous conduction modes. The potential applications lie in
power conversions which require fast response to line/load changes, such as the point of load
(POL) converters in the distributed power conversion system, power conditioning stage of the
conversion system supplied by renewable energy sources, and so on. Design procedures and
performance of the proposed control method applied on a 190 W 48/48 V buck-boost converter
prototype will presented and compared with theoretical predictions.
Keywords:
Boundary Control, Switching Surface Control, Second-order Switching Surface, State Trajectory Control, Sliding Mode Control
