Modified Current Sensorless Incremental Conductance Algorithm for Photovoltaic Systems

Abstract

This paper proposes a novel maximum power point tracking algorithm applied to photovoltaic systems. The proposed method uses the derivative of power versus voltage to define the tracking path and has the advantage of requiring only a voltage sensor to be implemented. The absence of the current sensor and the auxiliary circuitry employed for conditioning the current signal imply cost reduction, configuring the main contribution of the proposed method, whose performance is kept close to the classical incremental conductance method, even with the reduced number of components. A DC-DC zeta converter is introduced in the content of this work as an interface between a photovoltaic array and a resistive load. The paper describes the operating principle and presents the mathematical formulation related to the proposed algorithm. Interesting simulation and experimental results are presented to validate the theory by comparing the proposed method with its traditional version under several scenarios of solar irradiance and temperature.

Keywords

• current sensorless tracking algorithm
• incremental conductance
• maximum power point tracker