New Global Maximum Power Point Tracking Technique Based on Indirect PV Array Voltage Control for Photovoltaic String Inverters With Reduced Number of Sensors

Abstract

This paper presents a study regarding the development of a single-stage single-phase grid-tied photovoltaic (PV) inverter with a new Global Maximum Power Point Tracking (GMPPT) technique. The proposed strategy is based on the indirect PV array voltage control and allows for the development of PV inverter with reduced number of sensors, therefore, increasing the system reliability and reducing costs. The proposed strategy was denominated Sensorless PV Array Voltage Control for Global Maximum Power Point Tracking (SPVAVC-GMPPT). The static and dynamic accuracy of the GMPPT algorithm has been demonstrated to be over 99% under different operating conditions of irradiance and temperature and also under shading conditions, where multiple false Maximum Power Points (MPPs) occur. Simulation and experimental results are shown, compared, and discussed, with a 99,45% TF for standard-test conditions (STC– 25 °C and 1000 W/ $\text{m}^{2}$ ) and even higher (99,96%) under different irradiance and temperature proving the effectiveness of the proposed technique.

Keywords

• GMPPT
• grid-tied inverters
• photovoltaic systems
• sensorless