Photovoltaic module and array performance characterization methods for all system operating conditions

Abstract

Abstract. This paper provides new test methods and analytical procedures for characterizing the electrical performance of photovoltaic modules and arrays. The methods use outdoor measurements to provide performance parameters both at standard reporting conditions and for all operating conditions encountered by typical photovoltaic systems. Improvements over previously used test methods are identified, and examples of the successful application of the methodology are provided for crystalline-and amorphous-silicon modules and arrays. This work provides an improved understanding of module and array performance characteristics, and perhaps most importantly, a straight-forward yet rigorous model for predicting array performance at all operating conditions. For the first time, the influences of solar irradiance, operating temperature, solar spectrum, solar angle-of-incidence, and temperature coefficients are all addressed in a practical way that will benefit both designers and users of photovoltaics.

Improvement and validation of a model for photovoltaic array performance

“…Equation ( demonstrate the existence of a nearly linear relationship between the current at maximum power point and the effective irradiance (also shown by King, 1996) and the voltage at the maximum power point and the cell temperature. The data were curve fitted for these two cases, obtaining linear equations which were then used to find correlations for the current and voltage at the maximum power point.…”

“…As the air mass increases, the spectral content of irradiance changes and in many cases, affects the efficiency of the PV panel. King et al (1996King et al ( , 1998 have characterized this dependence in the form of a polynomial, function of the absolute air mass. Equation…”

“…The incidence angle modifier (K τα or M θ ) depends only on the incidence angle and strongly controls the amount of radiation absorbed by the panel. King et al (1996King et al ( , 1998 have developed this dependence in the form of a polynomial, function of the incidence angle (θ), and shown in Equation (2.6). …”

Explicit empirical relation for the monthly average cell‐temperature performance ratio of photovoltaic arrays

“…4 For Si cells operated at the maximum power point King 5 proposed the value of À0Á0045 K À1 for the coefficient , assumed constant in the following. We have adopted this value for all calculations presented here.…”

Photovoltaic module energy rating procedure. Final subcontract report

“…One currently used application of an IAM (King, 1996) applies the correction to the global plane of array irradiance. This application under high diffise conditions needs to be evaluated.…”