Sliding mode control of the four quadrant quasi-Z-Source DC-DC Converter

In order to regulate the output voltage in converter system with four-quadrant characteristic a quasi-Z-Source Converter (qZSC) is preferred. The converter can provide bi-directional current and bipolar output voltage with minimal number of elements. In this converter two active switches with complimentary commands and a quasi-Z-source network is required and there is no need to coupled inductors and additional more components. In this paper a reduced order model is proposed to output voltage regulation by means of variable structure control approach. The method employs sliding mode control (SMC) with the converter dynamic model. The proposed SMC approach guarantees stability as well as robustness against input voltage variation, parameters and load resistance uncertainty. In order to demonstrate the capability of the proposed controller, simulation results obtained by PSIM software are presented.