TY - GEN
T1 - Potential induced degradation of pre-stressed photovoltaic modules
T2 - 39th IEEE Photovoltaic Specialists Conference, PVSC 2013
AU - Ebneali, Faraz
AU - Tatapudi, Sai
AU - Tamizhmani, Govindasamy
PY - 2013/1/1
Y1 - 2013/1/1
N2 - Potential induced degradation (PID) is one of the factors that could contribute to the long-term degradation of PV modules. It is, therefore, essential to carry out the PID test for different open-air conditions as well as both voltage polarities for modules that maybe designated by the manufacturer to operate in either polarity. This paper evaluates the influence of PID test temperature, humidity-based and carbon-based surface conductivity of glass, and system voltage polarity on the degree of PID effects on fresh and pre-stressed (thermal-cycling or damp-heat) mono- and poly-crystalline silicon modules. Irrespective of PID test temperature (85oC or 60oC) and pre-history (fresh or pre-stressed in damp-heat or thermal-cycling), this work indicates that the positive-voltage has little or no PID effect on all the tested modules when humidity or carbon is used for the glass surface conductivity. In contrast, irrespective of PID test temperature (85oC or 60oC) and pre-history (fresh or pre-stressed in damp-heat or thermal-cycling), all the tested modules appear to be susceptible to the negative-voltage when conductive carbon (carbon layer) is used for the glass surface conductivity. However, when humidity is used for the surface conductivity instead of carbon, only the fresh and damp-heat stressed modules, excluding thermal-cycling stressed modules, appear to be susceptible to the negative voltage irrespective of PID test temperature (85oC or 60oC). It is also concluded that the humidity based approach may be a better replication of the field degradation (if any) pattern as compared to the metallic/carbon conductive layer approach.
AB - Potential induced degradation (PID) is one of the factors that could contribute to the long-term degradation of PV modules. It is, therefore, essential to carry out the PID test for different open-air conditions as well as both voltage polarities for modules that maybe designated by the manufacturer to operate in either polarity. This paper evaluates the influence of PID test temperature, humidity-based and carbon-based surface conductivity of glass, and system voltage polarity on the degree of PID effects on fresh and pre-stressed (thermal-cycling or damp-heat) mono- and poly-crystalline silicon modules. Irrespective of PID test temperature (85oC or 60oC) and pre-history (fresh or pre-stressed in damp-heat or thermal-cycling), this work indicates that the positive-voltage has little or no PID effect on all the tested modules when humidity or carbon is used for the glass surface conductivity. In contrast, irrespective of PID test temperature (85oC or 60oC) and pre-history (fresh or pre-stressed in damp-heat or thermal-cycling), all the tested modules appear to be susceptible to the negative-voltage when conductive carbon (carbon layer) is used for the glass surface conductivity. However, when humidity is used for the surface conductivity instead of carbon, only the fresh and damp-heat stressed modules, excluding thermal-cycling stressed modules, appear to be susceptible to the negative voltage irrespective of PID test temperature (85oC or 60oC). It is also concluded that the humidity based approach may be a better replication of the field degradation (if any) pattern as compared to the metallic/carbon conductive layer approach.
KW - Durability
KW - Leakage current
KW - Potential induced degradation
KW - Reliability
KW - System voltage
UR - http://www.scopus.com/inward/record.url?scp=84896486061&partnerID=8YFLogxK
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U2 - 10.1109/PVSC.2013.6744440
DO - 10.1109/PVSC.2013.6744440
M3 - Conference contribution
AN - SCOPUS:84896486061
SN - 9781479932993
T3 - Conference Record of the IEEE Photovoltaic Specialists Conference
SP - 1548
EP - 1553
BT - 39th IEEE Photovoltaic Specialists Conference, PVSC 2013
PB - Institute of Electrical and Electronics Engineers Inc.
Y2 - 16 June 2013 through 21 June 2013
ER -