The application relates to the field of
photovoltaic system performance evaluation, and discloses a photovoltaic module string output characteristic quantification method and model under near shadow. The method inputs
standard test condition electrical parameters of a photovoltaic module, including a short-circuit current, an open-circuit
voltage, maximum power point parameters, a
temperature coefficient, a
cell type and a series-parallel topology structure inside the module, calculates module-level parameters based on a single-
diode model, and maps the module-level parameters to
cell-level parameters through the topology structure inside the module. In combination with
irradiance and temperature under unshaded and shaded conditions, parameters such as photogenerated current and reverse
saturation current are dynamically adjusted to calculate
cell volt-
ampere characteristics. Then,
volt-
ampere characteristic curves of cells, sub-strings, modules and module strings are integrated step by step to finally obtain
voltage-current characteristics of the module string under near shadow. The method is suitable for full-cell modules, half-cell modules and
heterojunction modules, and can quickly and accurately quantify the output characteristics of the module string under shading conditions.