Maximum Power Point Tracking Algorithm Based on Fuzzy Logic Control Using P-V and I-V Characteristics for PV Array

Abstract

This paper presents a fuzzy logic-based maximum power point tracking (FL-MPPT) algorithm that employs both P-V and I-V photovoltaic (PV) array characteristics. In the given FL-MPPT algorithm, a new parameter ' <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">E_a</i> ' is employed, which is derived using I-V characteristics instead of the change in slope of P-V characteristics employed in conventional FL-MPPT algorithms. The usage of parameter ' <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">E_a</i> ' makes the MPPT algorithm more precise in computing change in duty ratio and increases the tracking performance for all environmental conditions (ECs). Further, the usage of parameter ' <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">E_a</i> ' supports the algorithm in distinguishing whether the operating point is near the maximum power point region or away from it (i.e., in the current source region (CSR) or in the voltage source region (VSR)). Thus, the proposed algorithm performs well in tracking peak power during low ECs, where conventional algorithms usually fail. Moreover, the conventional algorithms also fail to detect the operating point in CSR during step-changing ECs from high to low irradiance. The manuscript gives all the details of the conventional, and the proposed FL-MPPT algorithm with respect to the analysis of membership functions. In addition, the simulation and experimental results are presented for both the conventional and the proposed FL-MPPT algorithms to support the claims.