Nombre: JARDEL MERLIM FARIA
Tipo: MSc dissertation
Fecha de publicación: 04/05/2018
Supervisor:
Nombre |
Rol |
|---|---|
| EDUARDO PERINI MUNIZ | Advisor * |
Junta de examinadores:
| Nombre |
Rol |
|---|---|
| DANIEL JOSÉ CUSTODIO COURA | Co advisor * |
| EDUARDO PERINI MUNIZ | Advisor * |
| FLAVIO BARCELOS BRAZ DA SILVA | External Examiner * |
| WANDERLEY CARDOSO CELESTE | Internal Examiner * |
Resumen: This work presents the development of a prototype composed of a photovoltaic solar panel, a photovoltaic cell interconnection system by bypass diode and a data acquisition system in order to determine the number of bypass diodes required for minimizing the condition of momentary or permanent loss of cells from de photovoltaic module. This prototype consists of 30 polycrystalline cells connected in series, each cell being electrically interconnected individually or in a group to a bypass diode. The diode used is a Schottky type of power, being interconnected to the photovoltaic cells through electromagnetic relays, which are controlled by the first Arduino® microcontroller. The data acquisition system is composed of a power circuit based on the load and uncharged of capacitors, controlled by a second Arduino® microcontroller. The programming of the data acquisition system is done through Matlab® software and language, which interfaces with the used microcontroller. The programming receives input variables from the photovoltaic panel and Espírito Santo Federal Institute weather station such as voltage, current, solar irradiation, cell temperature, experiment time, number of cells per bypass device and number of shaded cells. Program outputs are current versus voltage and power versus voltage curves of the photovoltaic solar panel. The experiment is performed by total shading of one to six cells from the same row of the photovoltaic module, alternating the eight cell configurations by diode bypass, during three times a day for one month. The analysis of the results was performed using Spearman statistical correlation method, which pointed out relevant correlations between the input variables of temperature, irradiance, number of shaded cells and number of cells per diode bypass with the output variables form factor and efficiency. Results show that the form factor varies positively with the increase of the solar irradiation and in a negative way with the elevation of the temperature. The efficiency of the photovoltaic module is reduced by increasing the number of cells per by-pass diode and number of shaded cells. Finally, the number of bypass diodes required to provide the best efficiency condition for the photovoltaic panel used is related to one diode per cell for the theoretical condition and one diode for every five cells for the condition with cost savings.
