A Simple Solar Tracker Demo

C.P. Ravikumar

Texas Instruments

The mail I received  from Prof. Saravanan Pandyan came as a pleasant surprise. He has forwarded to me a link to a video demonstration of a project carried out by one of his former students.  Vignesh Raja, who graduated in 2013 from Amrita Institute of Technology, Coimbatore, has carried out a project on Solar Tracking.

Solar Tracking

From Sunrise to Sunset, the solar panel must be able to track the position of the Sun so as to maximize the amount of solar energy input that can be converted. Read the article “Maximum Power Point Tracking Solar Charge Controller” by two students of IIT Madras, published in a newsletter of TI India  University Program in Jan 2010. Vignesh’s interest is in coming with the necessary mechanism to move the solar panel in accordance to the movement of the Sun.   He uses two LDRs (light dependent resistors) as to detect the amount of insolation falling on the solar panel.  In an actual realization, more than two LDRs may be needed.  An H-bridge driver is used to drive a motor; the amount and direction of the current through the motor should depend on the amount of Sunlight falling on the panel, so that the panel moves in the right direction to receive more Sunlight.

The MSP430G2231 microcontroller is capable of reacting to the changes in the inputs coming from the sensors and adjust the direction and amount of current through the H-bridge using a control algorithm.   The project makes use of the on-chip analog-to-digital converter in the Texas Instruments Incorporated MSP430G2231 microcontroller (MSP430 Launch Pad). The L293D H-bridge driver (available from Texas Instruments ) is used to drive the motor.

The demonstration raises many questions that need further exploration. What is the control algorithm used for solar tracking and how optimal is the tracking? Can the optimality improved by using more sensors? If so, what is the optimal number of sensors? What challenges will having multiple sensors pose? For example, will the MSP430G2231 suffice? If not, why not? Texas Instruments provides a family of microcontrollers called C2000 which is often used in applications such as solar tracking – why?

What I found interesting in Vignesh Raja’s demo is that his experiment can be used as a framework in an experiment in a college lab.  He has made use of light-weight material to mimic a solar panel, so that a small HP motor will suffice for the purposes of illustration. Do watch his video and give him your feedback.

We encourage students to upload their projects to our project website.

Click on the picture to view the video!