Energy-Saving Led Lighting System With Parallel Power Supply By Photovoltaic Modules And By Network

The current state of LED lighting systems with parallel power supply by photovoltaic modules and central power supply network is analysed. The approach to implementation of parallel operation of LED luminaire powered by two sources of power is presented. It is simple, cheap and highly reliable as compared to the existing solutions. Based on this approach, four diagrams are developed which are applicable correspondingly to lighting applications and characteristics of photovoltaic modules and power consumers. The first and the second diagrams contain minimal quantity of transformers, but a number of operational constraints shall be taken into account when using them. The third diagram contains standard transformers and implies minimal number of various constraints, which makes it an optimal solution for the low-power lighting system being designed. The fourth diagram is expensive due to utilisation of equipment with automatic maximum power point tracking (the MPPT technology); it provides maximum possible energy efficiency of the lighting systems but the advantages of the MPPT technology apply only to high-power systems. It is preferable to use such objects where lighting is mostly required during daytime as consumers of such systems (shopping malls, underground passages, storage facilities, poultry farms, etc.). A positive aspect is increase in reliability of consumer power supply since power supply of LED luminaires will be also provided by an additional source. The proposed approach leads to reduction of power consumption for LED lighting, saving of fossil energy sources and therefore to ecologisation of the environment.