Abstract - Solar trackers rely on a direct-current (DC) motor driver circuit to control the movement of the solar panel. However, conventional DC motor drivers used in solar tracking system do not provide any options for speed and torque control. Hence, the fixed speed of the DC motor leads to either too fast or too slow tracking movement. Usually, the output torque is set to the maximum. If the load (solar panels’ weight) is small, the maximum torque is not fully utilized and therefore energy is wasted. So, a fully adjustable DC motor driver for solar tracking system shows great potential in commercialization because highly energy efficient DC motor driver circuit can improves the total efficiency of the solar tracker. Fewer solar panels are needed when they are attached to high efficiency solar tracking system, which will be reflected to lower system cost. Therefore, this enhanced motor driver will bring significant impact to the solar energy industry. The proposed DC motor driver is fully adjustable in term of speed and torque. The speed and torque of the motor is directly proportional to the output voltage and output current of the proposed DC motor driver, respectively. Adaptive controlling of the output voltage and current are possible by installing algorithm in the microcontroller of the DC motor driver and it can be reprogrammed according to the requirement. The speed control makes the solar tracking system to track the Sun more accurately and the torque control saves energy.
converter is used to step down the voltage in order to reduce the turning speed of solar panel [4].
Fig.1. Block diagram of motor driver
I.
INTRODUCTION
Solar tracking system is used to track the position of sun in order to get the maximum energy by aligned the solar panel perpendicular to the incidence sunlight [1, 2, 3, 12, 13]. Solar panels need to move along with the direction of sunlight during the