Higher order sliding mode control based duty-ratio controller for the DC/DC buck converter with constant power loads

Nowadays, most of the electric drives works with the help of a Medium Voltage DC (MVDC) supply. In MVDC power system, buck converters are commonly used for supply constant power load and its output voltage should be lesser than the input. The system has become unstable at certain instants due to some disturbances. A sliding mode control is a robust control technique with superior performance over conventional control techniques. In this paper, a higher order sliding mode controller using a super twisting algorithm is proposed for the duty ratio control of the DC/DC Buck Converter. This controller is able to control the system in any circumstances and stabilise the load power. The performances of the proposed method has been verified by simulation.