TY - GEN
T1 - Fast dynamical reconfiguration algorithm of PV arrays
AU - Balato, Marco
AU - Manganiello, Patrizio
AU - Vitelli, Massimo
PY - 2014/1/1
Y1 - 2014/1/1
N2 - In case of mismatch (due to clouds, shadows, dirtiness, manufacturing tolerances, aging, different orientation of parts of the PV field, thermal gradients, etc.), the Power versus Voltage (P-V) characteristic of a PV field may exhibit more than one peak, because of the adoption of bypass diodes, therefore Centralized Maximum Power Point Tracking (CMPPT) algorithms can fail. The consequent power drop can be avoided by using power optimizers, which are module dedicated dc/dc converters, or micro-inverters. The main drawbacks of such devices are the high cost and the reduced plant efficiency during the day hours in which the PV array works under a uniform irradiation level. This usually happens in the middle of the day, just when the PV power reaches the peak. Moreover, both the dc/dc and the dc/ac module dedicated converters introduce further components that may reduce the system lifetime, e.g. large electrolytic capacitances. A recent alternative is represented by the dynamical re-configuration of the PV array by means of active switches: in this way, the efficiency under uniform irradiation conditions is preserved and, in presence of mismatching, the best series/parallel modules configuration is achieved. This solution is cheaper than the one involving power optimizers and, besides the possibility of plant monitoring, offers additional advantages in terms of safety in case of fire. In this paper a novel approach to the PV string dynamical reconfiguration is presented and discussed.
AB - In case of mismatch (due to clouds, shadows, dirtiness, manufacturing tolerances, aging, different orientation of parts of the PV field, thermal gradients, etc.), the Power versus Voltage (P-V) characteristic of a PV field may exhibit more than one peak, because of the adoption of bypass diodes, therefore Centralized Maximum Power Point Tracking (CMPPT) algorithms can fail. The consequent power drop can be avoided by using power optimizers, which are module dedicated dc/dc converters, or micro-inverters. The main drawbacks of such devices are the high cost and the reduced plant efficiency during the day hours in which the PV array works under a uniform irradiation level. This usually happens in the middle of the day, just when the PV power reaches the peak. Moreover, both the dc/dc and the dc/ac module dedicated converters introduce further components that may reduce the system lifetime, e.g. large electrolytic capacitances. A recent alternative is represented by the dynamical re-configuration of the PV array by means of active switches: in this way, the efficiency under uniform irradiation conditions is preserved and, in presence of mismatching, the best series/parallel modules configuration is achieved. This solution is cheaper than the one involving power optimizers and, besides the possibility of plant monitoring, offers additional advantages in terms of safety in case of fire. In this paper a novel approach to the PV string dynamical reconfiguration is presented and discussed.
KW - grid connected PV systems
KW - Maximum Power Point Tracking (MPPT)
KW - mismatching
UR - http://www.scopus.com/inward/record.url?scp=84904490784&partnerID=8YFLogxK
U2 - 10.1109/EVER.2014.6843998
DO - 10.1109/EVER.2014.6843998
M3 - Conference contribution
AN - SCOPUS:84904490784
SN - 9781479937868
T3 - 2014 9th International Conference on Ecological Vehicles and Renewable Energies, EVER 2014
BT - 2014 9th International Conference on Ecological Vehicles and Renewable Energies, EVER 2014
PB - IEEE
T2 - 2014 9th International Conference on Ecological Vehicles and Renewable Energies, EVER 2014
Y2 - 25 March 2014 through 27 March 2014
ER -