Solar Cell Performance Measurement System
Team Astros has undertaken the task of designing and
implementing a Solar Cell performance measurement system
for Dr. David Zubia, assistant professor in the Electrical and
Computer Engineering (ECE) Department at the University of Texas
at El Paso (UTEP). This system will measure current and voltage (IV)
characteristics of test solar cells and will perform analysis and
The system is comprised of the following subsystems:
The program will provide the user with a GUI to enter the appropriate test
parameters to obtain the IV characteristics of a test solar cell. This cell, illuminated
by the light source, will be subjected to a voltage sweep via the LabVIEW program in
conjunction with the data acquisition board. During this voltage sweep, measurements of the
voltage across the cell and the current generated by it will be acquired, analyzed, plotted
and saved to a tab-delimited file for later importation into 3rd party software (e.g. Microsoft
Excel, Access, etc.) for later analysis.
- A bipolar data acquistion board connected to a computer
- A program to operate the system (GUI) using National Instrument's Laboratory Virtual Instrument Engineering Workbench software (LabVIEW)
- A Xenon lamp-based light source
Method of Completion
The work was divided among the three team members in the following manner:
- Enrique Fernandez was responsible for the research of a bipolar power supply and purchase
of a bipolar data acquisition board based on his research, consultations with Dr. Zubia and budget
limitations. Fernandez was also responsible for the development and implementation of a current-measuring
circuit designed to eliminate current loss from the test cell and compatible with the data acquisition board.
- Andy Castellanos was co-responsible with Fernandez in the research of the power supply and responsible for
the programming of the GUI using LabVIEW.
- Alberto Chico was responsible for the research and purchase of all the lighting-related
components, as well as the integration of these to the rest of the modules.
The current issues that the team must deal for the completion of this project are:
- Due to the very small current from the test cell being measured (in the range of a few mA), noise is
being picked up by the system when the xenon lamp-based light source is turned on. This problem does
not occur when the light source is off. This issued is currently being worked on.
- Due to a different configuration desired by the end user of the system, the single halogen lamp of the
original stressing light enclosure design might not be enough to uniformly illuminate with new number of cells
desired. Options are being evaluated for the resolution of this problem.
Test solar cells shall be characterized the week of November 18th, 2002. These cells will be stressed under
certain lighting conditions and re-characterized in order to evaluate any performance degradation. Once the system is
proven reliable to the Senior Project coordinators, Teaching Assistant, Dr. Zubia and the end user, the system will be
turned over to the end user for full use.