Sliding mode control of the Cuk converter

A sliding mode control strategy is proposed for a third order Cuk converter. Conventional switching surfaces for DC-DC converters of order greater than two contain one state variable set equal to a constant. This paper analyzes switching surfaces that are a linear combination of up to three state variables. These switching surfaces allow much more flexibility in controlling the output voltage and produce a response with small overshoot and a reduced reaching time period, as compared to the conventional surfaces used in earlier studies. Simulation and experimental results are reported. The results verify that the output voltage can be controlled and maintained at the desired level using the sliding mode control schemes developed.