The invention relates to a method for inspecting a photovoltaic element (1), preferably in order to determine the output and/or in order to determine defects of the photovoltaic element (1), and to a photovoltaic element (1) which is inspected using such a method.

A method for electricity-related security awareness of distributed power supply systems considering spatio-temporal distribution of rainstorms, including: establishing a multi-dimensional parallel parasitic capacitance calculation model of the distributed photovoltaic-energy storage power supply system considering accumulated water depth and micro-terrain environment; performing multi-source spatio-temporal hierarchical correlation analysis between rainstorm spatio-temporal distribution characteristics (including rainfall peak position, cloud movement, rainfall intensity and rainfall duration) and an operating state of the distributed power supply system; constructing a leakage current probability prediction model considering unevenness and randomness of the rainstorm spatio-temporal distribution; and establishing an electricity-related security awareness model based on deep meta-learning.

A method for electricity-related security awareness of distributed power supply systems considering spatio-temporal distribution of rainstorms, including: establishing a multi-dimensional parallel parasitic capacitance calculation model of the distributed photovoltaic-energy storage power supply system considering accumulated water depth and micro-terrain environment; performing multi-source spatio-temporal hierarchical correlation analysis between rainstorm spatio-temporal distribution characteristics (including rainfall peak position, cloud movement, rainfall intensity and rainfall duration) and an operating state of the distributed power supply system; constructing a leakage current probability prediction model considering unevenness and randomness of the rainstorm spatio-temporal distribution; and establishing an electricity-related security awareness model based on deep meta-learning.

This application provides a photovoltaic system and a maximum power point tracking control method for a photovoltaic system. The photovoltaic system includes an MPPT controller and a power converter, and the MPPT controller is connected to the power converter. The MPPT controller is configured to: be connected to a photovoltaic array, and track a global maximum power point MPP of the photovoltaic array. The MPPT controller may be further configured to obtain, when there is a periodic shade for the photovoltaic array, a multi-peak search start moment of global MPPT of the photovoltaic array based on a status of tracking the global MPP of the photovoltaic array in a target time period, so that when the multi-peak search start moment in each MPPT period arrives, the global MPPT of the photovoltaic array is started, to output a working point of the global MPP of the photovoltaic array to the power converter. According to this application, efficiency of obtaining the working point of the global MPP of the photovoltaic array can be improved, and precision of controlling the global MPPT of the photovoltaic array can be improved.

A method may include obtaining a normal set point of a solar panel and a wind velocity measurement corresponding to wind that affects the solar panel. The method may include determining an allowable range of tilt angles according to a first lookup table that describes a relationship between the wind velocity measurement and the allowable range of tilt angles. The method may include identifying whether the normal set point of the solar panel is outside of the allowable range of tilt angles, and responsive to identifying that the normal set point of the solar panel is outside of the allowable range of tilt angles, determining a temporary stow set point. The method may include rotating the solar panel to the temporary stow set point.

An abnormality determination system includes a power generation amount measurement unit that measures a power generation amount of the photovoltaic facility; a data acquisition unit that acquires data of a solar radiation amount; a calculation unit that divides a summed value of the power generation amount per day by a summed value of the solar radiation amount per day to calculates a division value; and a data accumulation unit that accumulates a combination of the power generation amount and the solar radiation amount, or the division value, and is configured to determine that there is an abnormality based on a slope of the division values.

An abnormality determination system includes a power generation amount measurement unit that measures a power generation amount of the photovoltaic facility; a data acquisition unit that acquires data of a solar radiation amount; a calculation unit that divides a summed value of the power generation amount per day by a summed value of the solar radiation amount per day to calculates a division value; and a data accumulation unit that accumulates a combination of the power generation amount and the solar radiation amount, or the division value, and is configured to determine that there is an abnormality based on a slope of the division values.

The present disclosure relates to a steady-state microwave conductivity method that includes modulating a light beam to form an amplitude modulated light having a modulation frequency ω.sub.1, producing a microwave waveform, exposing a sample to the amplitude modulated light and a first portion of the microwave waveform to produce an amplitude modulation signal on the first portion of the microwave waveform, and mixing a second portion of the microwave waveform and the amplitude modulation signal to produce a first signal and a second signal.

The present disclosure relates to a steady-state microwave conductivity method that includes modulating a light beam to form an amplitude modulated light having a modulation frequency ω.sub.1, producing a microwave waveform, exposing a sample to the amplitude modulated light and a first portion of the microwave waveform to produce an amplitude modulation signal on the first portion of the microwave waveform, and mixing a second portion of the microwave waveform and the amplitude modulation signal to produce a first signal and a second signal.

One example method includes obtaining output powers at initial scanning points of photovoltaic strings in a first group and a second group. The output powers at the initial scan points of the photovoltaic strings in the first group can then be controlled to sequentially decrease, and the output powers at the initial scan points of the photovoltaic strings in the second group can then be controlled to sequentially increase. Scanning can then be performed in the initial scanning direction starting from output voltages corresponding to the output powers at the initial scan points of the first group. Scanning can then be performed in the initial scanning direction starting from output voltages corresponding to the output powers at the initial scan points of the second group, where output powers of the first group and the second group are kept to compensate each other during IV curve scanning.