Fast-MPPT control algorithm capable of escaping Local Maximum Power Points

Abstract

The power-voltage (PV) characteristic of a photovoltaic (PV) string has multiple local maxima under partial shading conditions (PSCs). Maximum power point tracking (MPPT) control needs both accuracy and fast speed. However, due to the trade-off between accuracy and tracking speed, MPPT methods that complement them are not yet complete. Another issue is the inability to detect changes in the high-voltage side local maxima when operating at the low-voltage side maximum power point. This study proposes an MPPT method based on a system with current sensors in each module. This proposed method can detect individual short-circuit currents and estimate the maximum power point quickly and accurately, furthermore respond to changes in all power points. Through simulations, the MPPT method is compared with the conventional method (scan method) in terms of tracking time and accuracy．