A bidirectional buck-boost converter to supply LEDs from batteries during Peak Load Time

This paper presents a design methodology for a street lighting system based on light emitting diodes (LEDs) without energy consumption from the mains during the Peak Load Time (PLT) that uses batteries to supply the circuit during this period. Besides, when a failure on the mains occurs, the batteries can keep the system working as an emergency lighting system. The decrease in energy demand from the generation power plants and transmission lines, and the reliability improvement of the street lighting system (SLS) justify these applications. The use of LEDs for lighting applications presents benefits owing to its long useful life added to its high luminous efficacy, high color rendering index and directional light emission. In this system, a single DC-to-DC converter (buck-boost) supplies the LEDs from the mains, and also from a battery when necessary. The proposed system has high efficiency, high power factor, and complies with the IEC 61000-3-2 standard.