Overview:

Since 1999 students of the Bochum University of Applied Sciences have been developing solar-cars, which are exclusively powered by the energy of the sunlight.

In March 2011, I have joined the SolarCar electronics team to do my internship for 20 weeks.

more information can be found on The HS Bochum SolarCar Project Webpage

SolarCar system consists mainly of solar panels that generate electric energy, batteries to store this energy in order to operate an electric motor that can move the mechanical skeleton of the car.

My Task:

My task was to design an electronic circuit that is located between the solar panels and the batteries; it is called Maximum Power point Tracker (MPPT).

According to the characteristic curve of the solar panel, there is one specific operating point on which we can obtain the maximum power out of it. This point is called the maximum power point. The problem is that: this point is continuously changing with the environment circumstances such as sunlight intensity, temperature and the load.

The function of the MPPT is to determine the maximum power point, then operate the solar panel on a suitable load to track it.

MPPT Design:

To achieve this task, the perturb and observe method were used in designing the MPPT circuit. This algorithm is explained in the following figure. the attached pdf file contains the detailed design of this circuit, along with the source code and components list.

MPPT Design