Recycling the light emitted from illumination sources

Abstract

Photovoltaic (PV) is an interesting energy conversion source among the renewable energy source. Photovoltaic systems are know by the average person, not only by the media coverage of large PV plants or autonomous system, but also, by the PV power supply of small systems in a wrist watch, a pocket calculator, a car sunroof and many other applications. In this project, we are going to study the effectiveness of recycle and reuse of the illumination light by using solar panels. The energy that can be received by a solar panel (Manufacturer: Siemens Solar Industries, Model: SM10, Max. Power: 10W) operating under natural (sun light) and artificial light sources (such as Sodium lamp, Halogen lamp, MH lamp, florescent tube) at different temperature and radiation intensity are under investigation. The energy converted by the solar panel from different light source will then be used to charge a rechargeable battery which is used as a power supply for future use. Due to the high cost and the large area of PV arrays, the PV research goals reasonable accuracy, control capability, and efficient utilization of the PV power. Therefore, most of the PV problems can be overcome by operating the PV system at the Maximum-Power-Point (MPP) for every instant. For any directly coupled load to the PV array, there is corresponding operating point on the PV characteristics. This operating point is not necessary the MPP. So for a maximum power transfer from the PV array, a power converter design that adjusts its input impedance to a value equal to the optimum impedance of the PV array is required. A step-down DC-DC converter can match the array optimum impedance by controlling its switching duty cycle (PWM have been used in this approach). This work proposes a stand-alone PV system which consists of four subsystems : the Solar Panel, the power conditioning subsystem, the control subsystem, and the DC load subsystem. The control of the duty cycle of the DC-DC converter is achieved through a maximum-power-point tracking algorithm. Since Power (P) = Current (I) x Voltage (V), then we have the below derivation : P = IV ----- (1) For maximum power, we have dP/dV = 0 or dP/dI = 0 => dP/dV = V(dI/dV) + I = 0 => dI/dV + I/V = 0 ----- (2) or => dP/dI = I(dV/dI) + V = 0 => dV/dI + V/I = 0 ----- (3) Therefore, for MPP operation of the PV system, the criteria of (2) or (3) should be meet