Adaptive impedance matching optimal control method for cascaded DC-DC power supply system

Cascaded instability problem of the cascaded power supply system is one of the most important issues that bother the researchers for a long time. In this paper, an adaptive impedance matching optimal control method for the cascaded DC-DC power supply system has been proposed to solve the cascaded instability problem. The adaptive optimal control works based on the output voltage AC signal component sampling feedback technique and controlled variable resistance in order to adjust the output impedance of the DC-DC power converter. The proposed control method is tested in a cascaded DC-DC power supply system consisted of two Buck converters, the experimental results verify the validity and reliability of the adaptive optimal control method on cascaded stability improvement.