A converter and a power backfeed control method applied to a photovoltaic power generation system are provided. The power backfeed control method includes: controlling, according to a backfeed instruction, the converter to enter a backfeed mode, where in the backfeed mode, the converter can transmit energy of the power grid to a selected photovoltaic string with a corresponding number; determining a backfeed control voltage according to the backfeed instruction, and determining a voltage limit in a process of determining the backfeed control voltage; determining an actual backfeed voltage based on the backfeed control voltage and the voltage limit, where the actual backfeed voltage is a smaller one of the backfeed control voltage and the voltage limit; and controlling the converter to output the actual backfeed voltage to the selected photovoltaic string, to enable the selected photovoltaic string to generate an electroluminescent effect.

The present disclosure provides an energy identification method for a micro-energy device based on back propagation (BP) neural network, which includes the following steps: S1, sampling a dynamic voltage of a micro-energy device in an open-circuit state to obtain an original voltage signal, and denoising the original voltage signal by an adaptive threshold wavelet transform; S2, extracting an R wave peak value of the denoised voltage signal so as to obtain model input data; S3, establishing a BP neural network model, inputting data to train the model, and stopping training when a training error is smaller than a preset value, to obtain a qualified BP neural network model; and S4, identifying a to-be-identified voltage signal by using the BP neural network model obtained in the step S3. According to the present disclosure, accurate and rapid energy identification and classification can be carried out, and the classification result is reliable.

A method including: acquiring present operating state data of a photovoltaic array, wherein the photovoltaic array includes at least two photovoltaic strings in parallel, and the present operating state data includes present output current values of the photovoltaic strings and present irradiances corresponding to the photovoltaic strings. Determining present characteristic parameters of the photovoltaic array based on the present operating state data, wherein the present characteristic parameters include a present characteristic current value, a present current discrete rate and the present irradiances; and determining an operating state of the photovoltaic array by comparing the present characteristic parameters with standard characteristic parameters of the photovoltaic array. Determining a present operating state of a photovoltaic array by comparing present characteristic parameters determined based on real-time operating state data with standard characteristic parameters may improve the accuracy of determining the operating state of the photovoltaic array.

A method including: acquiring present operating state data of a photovoltaic array, wherein the photovoltaic array includes at least two photovoltaic strings in parallel, and the present operating state data includes present output current values of the photovoltaic strings and present irradiances corresponding to the photovoltaic strings. Determining present characteristic parameters of the photovoltaic array based on the present operating state data, wherein the present characteristic parameters include a present characteristic current value, a present current discrete rate and the present irradiances; and determining an operating state of the photovoltaic array by comparing the present characteristic parameters with standard characteristic parameters of the photovoltaic array. Determining a present operating state of a photovoltaic array by comparing present characteristic parameters determined based on real-time operating state data with standard characteristic parameters may improve the accuracy of determining the operating state of the photovoltaic array.

A system and method for automated shutdown, disconnect, or power reduction of solar panels. A system of solar panels includes one or more master management units (MMUs) and one or more local management units (LMUs). The MMUs are in communication with the LMUs with the MMUs and LMUs “handshaking” when the system is in operation. The MMUs are connected to one or more controllers which in turn are connected to emergency detection sensors. Upon a sensor detection of an emergency, the associated MMU is notified which in turn instructs associated LMUs to take appropriate action. In the event that communication with the MMUs has been cut off, the LMUs take the initiative to shut down, disconnect, or reduce the output of associated string(s) of solar panels.

A system and method for automated shutdown, disconnect, or power reduction of solar panels. A system of solar panels includes one or more master management units (MMUs) and one or more local management units (LMUs). The MMUs are in communication with the LMUs with the MMUs and LMUs “handshaking” when the system is in operation. The MMUs are connected to one or more controllers which in turn are connected to emergency detection sensors. Upon a sensor detection of an emergency, the associated MMU is notified which in turn instructs associated LMUs to take appropriate action. In the event that communication with the MMUs has been cut off, the LMUs take the initiative to shut down, disconnect, or reduce the output of associated string(s) of solar panels.

Methods, systems, and program products of inspecting solar panels using unmanned aerial vehicles (UAVs) are disclosed. A UAV can obtain a position of the Sun in a reference frame, a location of a solar panel in the reference frame, and an orientation of the solar panel in the reference frame. The UAV can determine a viewing position of the UAV in the reference frame based on at least one of the position of the Sun, the location of the solar panel, and the orientation of the solar panel. The UAV can maneuver to the viewing position and point a thermal sensor onboard the UAV at the solar panel. The UAV can capture, by the thermal sensor, a thermal image of at least a portion of the solar panel. A server onboard the UAV or connected to the UAV can detect panel failures based on the thermal image.

Methods, systems, and program products of inspecting solar panels using unmanned aerial vehicles (UAVs) are disclosed. A UAV can obtain a position of the Sun in a reference frame, a location of a solar panel in the reference frame, and an orientation of the solar panel in the reference frame. The UAV can determine a viewing position of the UAV in the reference frame based on at least one of the position of the Sun, the location of the solar panel, and the orientation of the solar panel. The UAV can maneuver to the viewing position and point a thermal sensor onboard the UAV at the solar panel. The UAV can capture, by the thermal sensor, a thermal image of at least a portion of the solar panel. A server onboard the UAV or connected to the UAV can detect panel failures based on the thermal image.

Various apparatuses and methods are provided for measuring the likely environmental impact of a particular geographic location on power generation properties of potential solar installations at the particular location. In an example embodiment of one such apparatus, a measurement device is provided. The measurement device includes a base portion comprising a base frame element disposed on a plurality of supporting legs, and a top panel comprising a series of connected members and one or more measurement modules whose planar dimensions are defined by the series of connected members. The top panel is connected to the base portion by a joint such that the top panel can rotate about the joint, and a panel support element is configured to fasten the top panel immovably at a desired degree of rotation in relation to the base portion.

The present disclosure is directed to a safety device for photovoltaic installations. The safety device includes a first terminal adapted to connect to a first output terminal of a solar panel, a second terminal adapted to connect to a second output terminal of the solar panel, a first switching module connected between the first terminal and the second terminal. The first switching module comprising a first switch and a first impedance connected in series. The first impedance includes one terminal connected to the first terminal and the first switch includes one terminal connected to the second terminal. A control module is adapted to read a control signal and drive the operation of the first switch based on the read value of the control signal. A powersupply means is adapted to supply power to the control module.