69776 - Laboratory of Photovoltaics

Learning outcomes

Knowledge about the operating principles, fabrication technology and design for photovoltaic cells and small photovoltaic plants.
Microcontroller-based control for small photovoltaic plants.

Course contents

1. Introduction to renewable energy conversion from sun
   1. Direct and diffuse solar radiation, map of solar radiation and standard reference spectra.
   2. Application examples (small to large solar plants, building integration).
   3. Outline of semiconductor physics, direct and indirect band-gap materials, light-matter interaction, optical generation, recombination mechanisms, analytical model of solar cells under dark and illumination conditions, solar cell figures of merit (short-circuit current, open-circuit voltage, fill factor, conversion efficiency, series and shunt resistance, quantum efficiency).
   4. Working principles of a p-n junction solar cell, equivalent lumped components circuital model.
   5. Loss mechanisms (recombination, optical and resistive), figures of merit sensitivity to temperature.
   6. Conversion efficiency theoretical upper bound limit.
2. Photovoltaic systems
   1. Solar panels (series and parallel cell connections, current and voltage mismatch, bypass and blocking diodes).
   2. Stand-alone and grid-connected systems.
   3. Maximum power point tracking (MPPT): Perturb & Observe algorithm and incremental conductance method.
   4. Inverter: design and working principle.
   5. Design of a small-power solar system ( < 10kW). Mono- and multi-inverter systems, mono and three-phase inverters.
   6. Grid connection.
3. Experimental measurement techniques
   1. Basics of measurement techniques for solar cells and modules.
   2. Experimental characterization of solar cells (dark and illuminated I-V characteristics, measurement of figures of merit and of shunt and series resistances, quantum efficiency, photoluminescence).
4. Modelling of photovoltaic systems and devices
   1. Introduction to SPICE circuit simulation.
   2. SPICE simulation of solar cells and modules.
   3. SPICE simulation of photovoltaic systems (photovoltaic array, power converters).
   4. Introduction to Simulink simulator.

Laboratory activity:

1. SPICE simulation of solar cells, modules. Effects of shading, current and voltage mismatch.
2. SPICE simulation of power conversion circuits.
3. Matlab/Simulink simulation of photovoltaic systems.
4. Design and implementation of circuits for power conversion (DC-DC boost).

Readings/Bibliography

[1] Luis Castaner, Santiago Silvestre, Modelling Photovoltaic Systems Using PSpice, Wiley, 2002 (ISBN: 978-0-470-84527-1).

[2] Adolf Goetzberger, Joachim Knobloch, Bernhard Voss, Crystalline Silicon Solar Cells, John Wiley & Sons, 1998 (ISBN: 978-0-471-97144-3).

[3] Martin A. Green, Solar Cells: Operating Principles, Technology, and System Applications, Prentice-Hall series in solid state physical electronics, 1981 (ISBN-13: 978-0138222703).

Teaching methods

Classroom teaching (30%)
Laboratory work (70%)

Assessment methods

Final exam is the only way to assess skills (theoretical and experimental) discussed during class and laboratory activities. The oral exam is aimed at testing the expected competence and covers the entire course program. During examination a report about all laboratory activities is discussed. The mandatory report must be prepared before the final test. The oral examination assesses also the language pertinence and correctness, the clarity and the conciseness of the report. The result of the final examination is a qualifying examination.

Teaching tools

SPICE simulator

Matlab/Simulink software tools

Experimental measurement setup

Microcontroller board

Office hours

See the website of Mauro Zanuccoli