A Remotely Control Dimming System for LED Lamps with Power Factor Correction

摘要

Modern street lighting systems require an energy-efficient dimmable road lighting system with even light distribution for safety and energy saving purposes. Existing standard TRIAC-based dimmers introduce power quality issues especially for a large-scale lighting network. This paper proposes a dimming control technique for Light Emitting Diode (LED) lamps, while maintaining high voltage and current quality. Dimming function is achieved by connecting a Voltage Source Converter (VSC) dimmer system between the AC supply and the lighting load. The VSC dimmer system will achieve high power factor and low current harmonic distortion when dimming the LED lamps. The VSC system is a comprehensive solution for most of power quality problems in the network. A VSC dimmer system prototype of 500 VA 120V has been built. An advanced feature is added to the VSC dimmer system to remotely send/receive messages between the system and the user through a Graphical User Interface (GUI). Specifically, the user can communicate with the VSC dimmer system by using Raspberry Pi. Experimental results and power analysis comparison between utilizing the TRIAC-based dimmer and the VSC dimmer system for dimming function are discussed. Setting a dimming profile to endorse energy saving will be discussed as well.