Design and Implementation of Peak Current Mode with PI Controller for Coupled Inductor-Based High-Gain Z-Source Converter

In this study, a peak current mode controller design and implementation is carried out for a high-gain integrated Z-Source DC-DC Converter. In this context, firstly, a small-signal dynamic modeling method for switching converters, based on volt-charge balance methodology, has been proposed and then applied to the Z-Source converter. With the proposed method, the modeling procedure of the integrated complex converters with multiple operating points can be simplified. To verify the obtained model, a small-signal simulation of the converter is also performed by using the Frequency Response Estimator tool of MATLAB/Simulink. The transfer function from the control current to the output was then obtained from the developed converter model to design the current mode controller. Then, a PI (proportional-integral) controller was designed according to the obtained transfer function, and a simulation study was performed with PLECS. Finally, an experimental study was carried out and compared with the simulation study. The results of the simulation and experimental studies show that the designed control method maintains the output voltage at desired levels regardless of the changes in load conditions and input voltage, successfully.