Employing Sliding Mode Control on a Two-Phase Voltage Regulator Module

Voltage regulator modules (VRMs) regulate its output voltage with small ripple voltage even in the presence of high load currents. They also experience loading conditions of high frequencies that are brought about by running software. Conventional linear controllers such as PIDs have already been utilized to address this, however, such controllers depend on the accurate modeling of the system to be controlled. In this study, we present a non-linear controller to achieve VRM performance criteria by utilizing the sliding mode control (SMC) principle. The VRMs will employ SMC in both its voltage and current share loops. We derive the sliding mode coefficients of a fixed frequency sliding mode controller and evaluate its performance under 10% and full load static load conditions. Simulation results have shown that the SMC-controlled VRM can regulate its output voltage, share the load current equally between its two phases, and achieve a low output ripple voltage.