Abstract: The invention relates to a method and device for diagnosing the operation of a photovoltaic module string. The method involves acquiring a series of current and voltage measurements forming a current versus voltage curve, known as the I(V) curve, and the steps of: transforming (46) into polar coordinates, each pair of current and voltage values of the I(V) curve, calculating (48-54) parameters of a first electrical model and second electrical model each approximating said I(V) curve, as well as a first cost representative of a deviation between said first model and said I(V) curve, and a second cost representative of a deviation between said second model and said I(V) curve, using a distance metric in the polar coordinate space, selecting (56) an electrical estimation model for estimating the I(V) curve and diagnosing (58) operation based on this selected electrical estimation model.

Abstract: A method estimating a series or parallel nature and a location of an arc in a photovoltaic device, operating under direct current, including N (N=1 or N>1) strings of photovoltaic modules, connected to a charge device having a capacitive behaviour for the modules, the method including: a) detecting, at terminals of each of the modules of each string, evolution of voltage over time, during formation of an electric arc; b) identifying the modules at the terminals of which a voltage variation occurs between a first zone with stable voltage and a second zone with stable voltage for a duration of at least 5 ?s, which immediately follows the voltage variation, and identifying the sign of each voltage variation; c) estimating the series or parallel nature and the location of the arc in the photovoltaic device.

Abstract: Method for detecting an electric arc in a photovoltaic installation, characterized in that it comprises the following steps: Measurement (E6) of voltage values at at least one site of the electrical circuit of the photovoltaic installation; Digitization (E8) of the measured voltage values so as to form a data sampling x; Computation (E10) of a first indicator of presence of an electric arc, on the basis of a statistical computation on the data sampling x, from among the variance, a value analogous to the variance, or the interquartile range of the data sampling; Computation (E10) of a second indicator of presence of an electric arc, on the basis of a statistical computation on the data sampling based on one or more estimations of the mean and/or of the median of the data sampling; Comparison (E12) of the first and second indicators of presence of an electric arc with respective thresholds so as to deduce therefrom the presence or absence of an electric arc within the photovoltaic installation.

Abstract: Method for detecting an electric arc in a photovoltaic installation, which includes measurement (E6) of voltage values at at least one site of the electrical circuit of the photovoltaic installation; digitization (E8) of the measured voltage values so as to form voltage data; formation (E11) of a window of n recent digitized voltage data; computation (E12) of a test value associated with the said window of the n voltage data; analysis (E13) of a test vector comprising m test values associated with m recent windows generating a quantity arising from this analysis representative of a risk of electric arc; comparison (E15) of this quantity arising with at least one threshold so as to deduce therefrom the presence or otherwise of an electric arc within the photovoltaic installation.

Abstract: A method detecting a parallel arc in a photovoltaic device, including N (N=1 or N>1) photovoltaic modules, connected to a charge device having a capacitive behavior for the modules, the method including: a) detecting, across main terminals of the device, evolution of voltage over time, at least during formation of the electric arc; b) identifying a negative voltage variation between a first zone with stable voltage and a second zone with stable voltage for a duration of at least 5 ?s, which immediately follows the voltage variation, and c) determining whether the voltage variation is between a maximum value Vmax, greater than or equal to 100 V, and a minimum value Vmin, less than or equal to 30 V, with a fall time of this variation between a minimum duration Tmin greater than or equal to 0.01 ?s and a maximum duration Tmax less than or equal to 10 ?s.

Abstract: A method estimating a series or parallel nature and a location of an arc in a photovoltaic device, operating under direct current, including N (N=1 or N>1) strings of photovoltaic modules, connected to a charge device having a capacitive behaviour for the modules, the method including: a) detecting, at terminals of each of the modules of each string, evolution of voltage over time, during formation of an electric arc; b) identifying the modules at the terminals of which a voltage variation occurs between a first zone with stable voltage and a second zone with stable voltage for a duration of at least 5 ?s, which immediately follows the voltage variation, and identifying the sign of each voltage variation; c) estimating the series or parallel nature and the location of the arc in the photovoltaic device.

Abstract: A method detecting a parallel arc in a photovoltaic device, including N (N=1 or N>1) photovoltaic modules, connected to a charge device having a capacitive behaviour for the modules, the method including: a) detecting, across main terminals of the device, evolution of voltage over time, at least during formation of the electric arc; b) identifying a negative voltage variation between a first zone with stable voltage and a second zone with stable voltage for a duration of at least 5 ?s, which immediately follows the voltage variation, and c) determining whether the voltage variation is between a maximum value Vmax, greater than or equal to 100 V, and a minimum value Vmin, less than or equal to 30 V, with a fall time of this variation between a minimum duration Tmin greater than or equal to 0.01 ?s and a maximum duration Tmax less than or equal to 10 ?s.

Abstract: Method for detecting an electric arc in a photovoltaic installation, characterized in that it comprises the following steps: Measurement (E6) of voltage values at at least one site of the electrical circuit of the photovoltaic installation; Digitization (E8) of the measured voltage values so as to form a data sampling x; Computation (E10) of a first indicator of presence of an electric arc, on the basis of a statistical computation on the data sampling x, from among the variance, a value analogous to the variance, or the interquartile range of the data sampling; Computation (E10) of a second indicator of presence of an electric arc, on the basis of a statistical computation on the data sampling based on one or more estimations of the mean and/or of the median of the data sampling; Comparison (E12) of the first and second indicators of presence of an electric arc with respective thresholds so as to deduce therefrom the presence or absence of an electric arc within the photovoltaic installation.

Abstract: Method for detecting an electric arc in a photovoltaic installation, which includes measurement (E6) of voltage values at at least one site of the electrical circuit of the photovoltaic installation; digitization (E8) of the measured voltage values so as to form voltage data; formation (E11) of a window of n recent digitized voltage data; computation (E12) of a test value associated with the said window of the n voltage data; analysis (E13) of a test vector comprising m test values associated with m recent windows generating a quantity arising from this analysis representative of a risk of electric arc; comparison (E15) of this quantity arising with at least one threshold so as to deduce therefrom the presence or otherwise of an electric arc within the photovoltaic installation.