Novel control algorithm for MPPT with Boost converters in photovoltaic systems

Abstract

The great advances in efficiency and performance of photovoltaic modules would not be very useful if they do not work close to their maximum power point (MPP). In this paper a novel Sliding Mode Control (SMC) based algorithm is proposed to be implemented in a DC/DC converter in order to make an autonomous photovoltaic system to work at the MPP. Once that the design of the novel algorithm has been detailed (especially the novel part relative to the current reference signal) and its stability has been demonstrated, its performance has been compared with two of the most commonly used algorithms in this scope, i.e., Perturbation & Observation (P&O) and Incremental Conductance (IC) algorithms, in addition to a PI controller because it is one of the preferred controllers in industrial applications. This comparison has been carried out taking into account both simulated and experimental tests. The first focused on their behavior when sudden changes in irradiance and temperature, while the lasts analyzed them when the load resistance was varying arbitrarily in actual facilities (composed of a photovoltaic module Mitsubishi PV-TD185MF5, a Boost converter, a variable load and a real-time data acquisition card dSPACE DSP1104 used as the interface between the control algorithm implemented in Simulink/Matlab and the real photovoltaic module). After completing tests under different conditions, we found that the proposed SMC based algorithm outperforms the PI controller and the P&O and IC algorithms, especially in experiments carried out using actual facilities.