Real-Time Digital Simulation and Analysis of Sliding Mode and P&O MPPT Algorithms for a PV System

This paper presents an integral Sliding Mode Controller (SMC) of a DC-DC boost converter integrated with a photovoltaic ( PV) system for maximum power extraction. In view of improving the steady-state performance of the maximum power point tracking ( MPPT), an integral of the error term is included in the sliding surface. The output of PV panels is connected to a DC-DC boost converter to regulate and enhance the voltage up to a desired level. By using SMC with integral term, the steady-state condition is obtained at less than 0.1 sec. With the proposed ISMC MPPT the maximum power extracted is more than 10% than the traditional Perturb & Observe (P&O) MPPT at standard test conditions (STC). The results obtained using the SMC are compared with that of the fixed step size P&O MPPT controller. The performances of the proposed sliding mode controller and the P&O controller are validated through experimentations using a Real-Time Digital Simulator (RTDS)-Opal RT.