Short-current pulse based adaptive maximum-power-point tracking for photovoltaic power generation system

Abstract

This paper proposes a novel maximum-power-point tracking (MPPT) method with a simple algorithm for photovoltaic (PV) power generation systems. The method is based on the use of a short-current pulse of the PV array to determine an optimum operating current for the maximum output power and completely differs from conventional hill-climbing based methods. In the proposed system, the optimum operating current is instantaneously determined by taking a product of the short-current pulse amplitude and a parameter k because the optimum operating current is exactly proportional to the short current under various conditions of illuminance and temperature. Also, the system offers an identification function of k by means of fast power-vs.-current curve scanning, which makes the short-current pulse based MPPT adaptive to disturbances such as shades partially covering the PV panels. The above adaptive MPPT algorithm has been adopted to a current-controlled boost chopper and a multiple power converter system composed by PV-chopper modules. Various operating characteristics have been examined, and excellent MPPT performance has been confirmed through the experimental tests.