PowerPoint Presentation

Dual Axis Solar Tracker

Cairo UniversityFaculty of engineeringDepartment of Electrical Power

Introduced to: DR / Khalid Ali El-MetwallyPrepared by:Islam Adel Ateya SEC : 2 BN:10

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MotivationIt is observable that the solar power is an important field that the whole world seeks to make the best use of it in order to decrease the use of fossil fuels that pollutes the environment. But the high initial cost of solar power has limited its wide usage for many poor countries. So that , the objective now is to increase the efficiency of solar systems in order to decrease its high initial cost.

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MotivationFor this reason solar tracker system is presented as a solution for solar systems in order to make the best possible use of the incident solar power .Solar tracker is an automatic control system that directs the absorber surface directly towards the sun .For the PV panels , solar tracker is considered a supplementary system. But for another systems they will be useless without solar tracking such as parabolic trough , parabolic dish and central receiver . 21/12/20153

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There is two types of solar tracker:1- Single axis : at which the absorber surface is mounted along the north south axis .2- Dual axis : at which the absorber surface is mounted towards the south direction . In this slides a prototype of dual axis solar used for solar panels tracker will be illustrated.21/12/20155

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Y-Z Plane MechanismAs shown in the mechanical schematic, the linear actuator is responsible for moving the panel in the Y-Z plane.The actuator is supposed to have holding torque to eliminate the disturbance caused by the wind, in addition to have low speed as the dynamic motion of the sun is slow.It was fond that the linear actuator is a good solution.21/12/20157

What is Linear Actuator?

Linear Actuator is a simple mechanism that converts the rotational motion of the DC motor into longitudinal motion.The linear actuator is provided with two limit switches to reset the motor at the boundary of the longitudinal motion not to present the shaft of the motor to be locked.

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X-Y Plane MechanismAs previous the X-Y actuator it is required from the actuator to have slow response and holding torque.It was found that a worm gear package would be suitable.

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What is Worm Gear

As shown worm gear package consists of two gears:.-Worm shaft Gear.- Worm Wheel GearAs the worm shaft rotates in the Y-Z Plane, The worm Wheel is forced to rotate in the perpendicular plane X-Y

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Sensing system

The sensing system consists of 3 light sensors mounted on a plastic base and separated of each other.This base should be installed in the same plane as the panel.The sensors are LDR sensors that stand for Light dependent Resistor .21/12/201511

Sensing system

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Sensing systemThe output voltage is not linearly proportional to sensor resistance, but it is desired to compare the illumination of the three sensors , so that linearity is not needed. The output voltages of the three sensors are read by the microcontroller.The controller compares between the readings and takes necessary control actions to set the panel at the position at which the incident radiation is approximately perpendicular to the solar panel21/12/201513

Flow Chart

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Circuit Diagram

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