LAUSR

A constant frequency double-integral sliding mode controller (DISMC) is proposed for the regulation of a four-quadrant continuous gain dc–dc converter based on quasi- $Z$ -source (ZS) topology. No controller has yet been proposed for the control of this particular converter in the literature so far. Four-quadrant converters based on hybrid ZS networks or coupled inductors have been proposed in the past, but this converter is unique in the sense that it uses minimum number of passive devices and active switches to provide bidirectional current and bipolar output voltage. This makes the converter preferable to use in renewable energy or motor drive applications that require a four-quadrant operation. The proposed controller eliminates steady-state errors and provides robust control in the face of large input voltage or load variations. It enables the converter to provide a fast dynamical response over a wide operating range. Simulations of the proposed controller have been performed in MATLAB/Simulink, where the results of DISMC have also been compared with those of single integral sliding mode control.