solar tracker report with lm358

[jaseela123d]

The amount of energy converted depends on the amount of light that falls on the Panel. Generally, solar panels are fixed devices that are fixed in one position. The electrical energy produced can be increased if we move the solar panel as the movement of the sun. Here is a simple low-cost solar circuit that automatically moves the solar panel in the direction of the sun. The movement of the Sun is detected using two LDRs that are arranged in the Solar Panel in such a way that the intensity of the falling light varies as the direction of the Sun changes.

Circuit diagram

Working

The heart of the circuit above is two voltage comparators made using LM358 Dual Op-Amp. We all know that when the intensity of light falling on an LDR increases, its resistance decreases. Here LDR is connected to a series resistor (R3 and R4), therefore, when the intensity of the light falling on an LDR increases, the voltage across the corresponding resistance (R3 or R4) increases.

The output of the voltage comparator will be high when the voltage in the non-inverting terminal (+) is greater than the voltage in the inverter terminal (-). The reversing terminals (-) of both comparators are short-circuited and connected to a variable resistor (RV1), which is used to establish the reference voltage. Therefore, the sensitivity of both LDR can be adjusted by varying the 10K potentiometer shown on the left side of the circuit diagram. When the light falls, an LDR increases, the voltage at the non-inverting terminal (+) of the corresponding comparator increases and its output rises HIGH.

The direction of motor rotation is controlled by the H-Bridge formed by the complementary symmetry transistors BC547 and BC557. Consider the case when the output of the first comparator (U1: A) is high and the output of the second comparator (U1: B) is low. In this case, transistors Q1 and Q4 will turn on and the resulting current will turn the motor clockwise. Consider the case when the output of the first comparator is low and the output of the second comparator is high. In this case, transistors Q2 and Q3 will turn on and the resulting current will rotate the motor counterclockwise. If the output of both comparators is low, transistors Q3 and Q4 turn on, but no current will flow through the motor. Similarly, if the output of both comparators is high, transistors Q1 and Q2 turn on, but no current will flow through the motor.

The DC motor must be connected to the panel in such a way that the rotation of the motor turns the panel in the direction of the sun's movement.