Implementation of a Stand-Alone Photovoltaic Lighting System with MPPT, Battery Charger and High Brightness LEDs

This paper presents a high-efficiency stand-alone photovoltaic (PV) lighting system which can provide functional illumination based on high-brightness light-emitting diodes (HBLEDs). HBLED with specific features of small size, long life and low power consumption will be choices of future light sources. In order to provide a steady-state operating environment for HBLEDs, a specially designed lighting power module is implemented. Maximum power point tracking (MPPT) and the on/off charging method are implemented in this system. Further more, a strategy to charge the battery is designed from the analyses and comparison results. The prototype of this microprocessor-based charger performs a good control on the switching modes among battery charge regulation and brightness control. Experimental results show the performance of the proposed photovoltaic lighting system.