Design and Implementation of a Digital High-Performance Photovoltaic Lighting System

This paper presents the design and implementation of a digital high performance photovoltaic lighting system based on a microcontroller. In order to achieve high lighting efficiency, this lighting system module used the HBLED which possesses small size, long life and low power consumption. The proposed system consists of a photovoltaic module, a LED lighting module, a bidirectional buck-boost converter and a battery. The bi-directional buck-boost converter is the integration of a charger/discharger and a LED lighting-module drive circuit, which can fulfill maximum power point tracking (MPPT), multi-stage current charging control and LED drive control. In addition, a microcontroller (PIC16F873) is used to realize the system controller. Finally, experimental results are provided to verify the theoretical analysis and design procedure of a digital controlled photovoltaic lighting system.