Under the existing technology, to reduce the cost of photovoltaic power generation, in addition to improving the energy conversion rate of the photovoltaic cell device, the photovoltaic cell array also needs to follow the sun to receive the maximum radiant energy. The working principle of the solar photovoltaic power generation tracking device is to make the photovoltaic array move with the movement of the sun. Although the position of the sun in space changes all the time, its operation has strict regularity, which is convenient for the tracking system to always detect the position of the sun and the photovoltaic array and input it to the control unit. The control unit compares the solar position signal with the photovoltaic array position signal, and generates a corresponding output signal to drive the rotating mechanism, so that the sun’s rays are always perpendicular to the surface of the photovoltaic array to obtain the maximum power generation efficiency. Practice has shown that under the same conditions, photovoltaic arrays with automatic tracking equipment can generate more than 30% more power than stationary equipment, and reduce costs by 25%. The automatic tracking system starts to track the change of the sun’s position from the morning, so that the condenser always receives the strongest solar radiation. When the sun sets or the sky light is extremely poor, the condenser automatically returns to the initial position facing the east, and when the sun rises or the sky light becomes stronger, it continues to track the strongest light.
The photoelectric tracking device uses sensors to detect the incident azimuth angle of the sun on the photovoltaic cell array. When the deviation between the sun’s rays and the optical axis of the system exceeds a threshold, the motor is controlled to drive the mechanical part to rotate to reduce the deviation until the sun’s rays are parallel to the optical axis of the system to realize the tracking of the sun’s altitude and azimuth. Its control principle is shown as in Figure 1.
Depending on the day’s motion trajectory tracking device, a preset clock program is used to regularly or continuously control the rotation of the drive motor to track the local solar time angle. It is divided into a timing clock method and a program tracking method.
The tracking principle of the timing clock method is shown in Figure 2. First determine an initial position, according to the sun’s movement angle per minute in the sky and the difference between the sun’s relative position at a certain moment, calculate the angle at which the solar panel should rotate per minute, and then calculate the number of pulses required for the motor to rotate through the difference, so that the solar panel changes accordingly according to the position of the sun.
The principle of the program tracking method is shown in Figure 3. Use the formula to calculate the position of the sun at a given time by the computer, and then calculate the required position of the tracking device, and finally send it to the processor through the serial port to control the motor rotation device to realize the tracking of the sun’s altitude and azimuth; or use the processor of the control device to calculate the formula to obtain the required data, and then use the motor to control the battery panel.