Solar light emitting diode (LED) street lighting with automatic vehicle detection system

Abstract

This thesis is about a development and fabrication of solar light emitting diode (LED) street lighting with an automatic vehicle detection system. Present available solar street lightings are operated based on the timer or light sensor which continuously turns on during night time even though the street is empty i.e. without any vehicle passing through it. To overcome this problem a system that was able to detect a vehicle at night using light dependent resistor (LDR) and microcontroller was designed. The microcontroller controlled the whole operation of the system, including the charging and discharging of the battery and the illumination of the LED lamp. The project comprises of the development of the DC to DC boost converter, dark and vehicle detection sensor and LED lamp driver. The boost converter system was designed to overcome the problem due to the lower output voltage from the solar panel compare to the optimum level of batteries charging voltage. From the experiment the output voltage from this DC to DC boost converter was 14.5 volts which is the optimum charging voltage. The vehicle and weather condition was detected by the vehicle and dark sensors. The test determined the distance of the incoming vehicle that the sensor can detect. During low beam testing the sensor managed to detect a vehicle at 80m away from it. For the high beam the vehicle detected by the sensor at 170m from it. In order to turn on the LED lamp, a DC relay system was developed. This relay controlled the electrical supply from batteries to the LED lamp. The complete circuit for this system was developed on the printed circuit board (PCB). The experimental results show that the system can charge the battery from 20% to 100% within a day. The battery chose was adequate to supply enough power to the load for 10 hours. The incoming vehicle on the street can be detected by vehicle sensor. While the dark sensor can distinguish between day and night condition.