Design of a sliding-mode-controlled dc-dc converter for MPPT in grid-connected PV System

This paper proposes a new control design approach for fast tracking of maximum power point in grid-connected PV system based on sliding-mode technique. This new proposed design model tracks the voltage reference provided by the MPPT algorithm regardless of the changes in the irradiance and temperature. The parameters of the sliding surface and second-order filter are calculated numerically by solving the non-linear set of equations. To guarantee the stability of the proposed controller, a complete mathematical study iscarried out to explain the fulfillment of the control conditions. To maintain the oscillations at the DC-link voltage, an inverter current control scheme is also proposed which make it easier to track the maximum power point. With the help of detailed simulation and comparative study, the results of the proposed sliding mode design exhibitsless settling time, no overshoot, fast tracking response as compared to cascaded PID controller.