2337 results about "Photovoltaic system" patented technology

The invention aims to provide an intelligent diagnosis method and system for a temporarily-built photovoltaic fault based on a knowledge graph, and belongs to the technical field of temporarily-built photovoltaic fault diagnos.The method comprises the steps that firstly, current, voltage, temperature and irradiance data of a temporarily-built photovoltaic system are collected, and multi-dimensional feature parameters are generated through abnormal value elimination, noise filtering and feature fusion; secondly, constructing a temporarily built photovoltaic knowledge graph containing equipment entity nodes, fault mode nodes and a topological connection relation, and calculating a topological connection weight based on historical fault data and an equipment rated power difference value; then, the multi-dimensional characteristic parameters are matched with fault mode nodes of the knowledge graph, fault propagation path reasoning is carried out through bidirectional breadth-first search and path weight screening, and fault types and positioning information are output; and finally, dynamically updating the association weight of the knowledge graph according to operation and maintenance feedback. The rapid and accurate diagnosis of the fault is realized, the downtime is obviously reduced, and the operation efficiency and the economic benefit of the temporarily built photovoltaic system are improved.

The invention relates to the technical field of photovoltaic systems, and particularly discloses a fault identification method and system for a photovoltaic system, and the method comprises the steps: collecting data in real time through environment, electrical parameters and an equipment state monitoring sensor, carrying out the cleaning and standardization, extracting time domain, frequency domain and time frequency features, and screening a feature subset through a correlation analysis and feature importance sorting algorithm; detecting and classifying faults by using a hybrid model composed of an isolated forest algorithm and a random forest classifier; positioning a fault subsystem and analyzing a root cause by means of a hierarchical diagnosis strategy, a graph neural network and a Bayesian reasoning algorithm; and periodically updating the model based on the new data. The method can quickly and accurately identify and position faults, adapts to a complex environment, reduces the operation and maintenance cost, and improves the operation reliability and operation and maintenance efficiency of a photovoltaic system.

The APSO-SA-based photovoltaic system maximum power point tracking control method comprises the following steps: constructing a photovoltaic system model, and carrying out parameter and particle swarm initialization on a preset APSO-SA algorithm in MPPT control; voltage and current of the photovoltaic system model are collected in real time, the initialized APSO-SA algorithm is input for optimization iteration, and the optimal duty ratio is obtained; and adjusting the working state of the boost converter based on the optimal duty ratio, so that the photovoltaic system operates at the optimal duty ratio, and tracking of the maximum power point is realized. According to the method, the MPPT system can rapidly relocate the maximum power point when illumination suddenly changes, meanwhile, high-precision tracking is maintained in a steady state, and the energy capture efficiency of a photovoltaic system is remarkably improved.

The present application relates to a solar cell, a method for manufacturing the same, a photovoltaic module and a photovoltaic system. The solar cell includes: a substrate (110), including a first surface (S1) and a second surface (S2) being opposite to each other, wherein the first surface (S1) has a first region (A) and a second region (B) adjacent to each other in a first direction; a passivating contact layer (120), located in the first region (A) of the first surface (S1); a polysilicon layer (130) located on at least a part of a surface of the passivating contact layer (120) away from the substrate (110); the passivating contact layer (120) including a first tunneling layer (121) and a first doped layer (122), the first tunneling layer (121) and the first doped layer (122) being sequentially stacked on the first region (A) of the first surface (S1) of the substrate (110) in a direction away from the second surface (S2); and a first passivation layer (140), located on a surface of the polysilicon layer (130) away from the passivating contact layer (120) and on the second region (B) of the first surface (S1).

The invention provides a photovoltaic system-based generating capacity loss intelligent evaluation method, which comprises the following steps of: 1, acquiring optical parameters in real time, and synchronously acquiring predicted irradiation data of a meteorological station; step 2, performing feature extraction on the current and voltage curve, identifying abnormal inflection points in the curve, dividing mismatch types, determining theoretical output power of each group of strings, and generating a future theoretical generating capacity baseline; 3, obtaining a group cascade stage power loss rate, and determining a current loss reason in combination with a mismatch type; 4, identifying a current system-level fault area; and step 5, based on a historical fault case library, extracting a group cascade power loss rate, a mismatch type and spatial distribution characteristics of a system-level fault area, matching a loss mode of a current system with a historical fault type, generating an evaluation report including a loss quantized value, a fault position and a repair priority, and carrying out fault recovery. And an optimization operation and maintenance instruction including a personnel scheduling scheme and a spare part demand list is generated. And the operation efficiency and the maintenance effect of the photovoltaic system are improved.

The invention discloses a micro-grid power control method, system and device based on fuzzy modulation and a storage medium, and relates to the technical field of intelligent grid integration of a photovoltaic system and a micro-grid, and the method comprises the steps: firstly obtaining the real-time power data of a photovoltaic system, carrying out the control processing through fuzzy logic, and calculating a reference instruction; according to the reference instruction, hysteresis time is dynamically adjusted through modulation hysteresis control, and an inverter switching signal is generated; converting direct current into alternating current based on the switching signal and a power switching device, injecting the alternating current into the micro-grid, calculating active and reactive power reference values, ensuring that the system operates according to a unit power factor, and giving active power to the reference value; according to the method, the power control precision and adaptability of the micro-grid are improved, excessive switching of the inverter is avoided, loss is reduced, the service life is prolonged, power matching and stable transmission are achieved, reactive loss is reduced, bus voltage is stabilized, harmonic waves can be reduced, the electric energy quality is improved, and efficient and stable operation of the micro-grid is guaranteed.

The invention discloses a wind and light storage coordination control method and system for a virtual synchronous machine, and the method comprises the steps: building a wind power plant-energy storage power station double-layer response mechanism at a first stage, and employing a multi-time scale coordination control strategy for a second-stage energy storage system; and in combination with the virtual synchronous control characteristics of the optical storage power station, establishing a multi-scene optimization model of a wind and light storage multi-source collaborative double-layer coupling mechanism, and realizing dynamic optimization of output of each unit among inertia support, frequency modulation capacity and energy storage health state. According to the method, wind power plant rotor kinetic energy release combined overspeed load shedding control, a fuzzy control means based on an energy storage charge state and a VSG control means based on a virtual inertia and damping coefficient self-adaption photovoltaic system are considered, then wind and light energy storage frequency modulation coordination is optimized, and the system inertia safety is effectively improved on various working conditions and different time scales.

The invention relates to the technical field of power quality monitoring, and discloses a method for identifying power quality disturbance characteristics of a distributed photovoltaic interference power supply, which comprises the following steps: S1, data acquisition and preprocessing: acquiring a power quality signal of a photovoltaic system and carrying out denoising, normalization and time alignment; and S2, carrying out disturbance signal adaptive decomposition based on improved variational mode decomposition, and automatically selecting a mode number by utilizing information geometric optimization. An improved variational mode decomposition method is adopted, information geometric optimization and Bayesian optimization are combined, self-adaptive mode decomposition of disturbance signals is achieved, the optimal mode number and penalty factors can be automatically determined through improved variational mode decomposition, decomposition errors caused by manual parameter setting in traditional variational mode decomposition are avoided, and the method is suitable for large-scale popularization and application. Compared with a fixed parameter variational mode decomposition method in the prior art, the method has the advantages that the analysis capability of complex disturbance signals is improved, and the disturbance mode in the photovoltaic system is accurately decomposed.

The invention relates to the technical field of photovoltaic intelligent operation and maintenance, and discloses a distributed photovoltaic intelligent operation and maintenance system. The method comprises the following steps: acquiring operation parameters such as voltage output, current intensity, temperature and ambient light of a plurality of photovoltaic units in real time; classifying the performance state of each photovoltaic unit based on the parameters, and identifying an efficient operation area, a performance attenuation area and a potential fault area; secondly, extracting rules from the maintenance strategy database, and constructing a mapping relation between the performance partition and the maintenance strategy; then determining a key partition according to the partition priority weight and the system impact factor, and optimizing the matching degree of the maintenance strategy combination; then, the real-time operation state of the system is checked according to the optimized combination, the maintenance demand change is recognized, and the mapping relation is updated; and finally, determining a maintenance target and an execution sequence according to the updated mapping relationship, and generating a structured operation and maintenance management library to guide subsequent maintenance activities. The method can improve the operation and maintenance efficiency and accuracy, and guarantees the stable and efficient operation of the photovoltaic system.

The invention relates to the technical field of intelligent building energy management, in particular to a power management optimization method based on an intelligent building green energy system, which is used for solving the problem of energy supply and demand imbalance caused by high time-varying characteristics of photovoltaic output and load demand in an intelligent building. The method comprises the following steps: firstly, establishing models of an intelligent building energy system, including a photovoltaic system, an energy storage system, a controllable load and a power grid interaction model; performing time-frequency domain analysis on photovoltaic output and load demand by using short-time Fourier transform, and decomposing a time sequence into a trend term, a periodic term and a random fluctuation term; a multi-time scale prediction model is constructed based on the decomposition result, and different prediction methods are adopted for different frequency domain features; and a hierarchical model prediction control framework including a day-ahead planning layer, an hour-level economic dispatching layer and a minute-level real-time control layer is further established, and multi-time-scale coordination control is realized.

The invention provides a photovoltaic module support amplitude stabilizing device, which relates to the technical field of photovoltaic equipment and comprises a support amplitude stabilizing execution module, a data acquisition module, a windproof control type determination module and a windproof control module. By constructing a three-level windproof control strategy system, accurate response to different wind levels is achieved, a first-level windproof control strategy is adapted to the vibration frequency and amplitude of a support in real time by dynamically adjusting the damping coefficient of a damping shock absorber, and a second-level windproof control strategy is adapted to the length of a windproof hydraulic cylinder based on wind speed and wind direction data. According to the three-level windproof control strategy, when strong wind exceeds a mechanical counteracting range, the dip angle of the photovoltaic panel is adjusted to a safe and efficient conversion angle, the wind resistance and the light energy utilization rate of the structure are balanced, and the wind energy utilization rate of the photovoltaic panel is increased. And the reliability and the economical efficiency of the photovoltaic system under the severe weather condition are improved.

The invention relates to the technical field of building structure reinforcement, and discloses a calculation method for increasing photovoltaic reinforcement on the roof of an existing building, which comprises the following steps of: constructing a load distribution model containing a vertical load layer (self weight of a photovoltaic module and accumulated snow load) and a horizontal load layer (wind load and earthquake load), and cooperatively transmitting the load through a node support system and an anchoring connecting piece; generating a roof reinforcement analysis model containing a supporting node model and a connecting component model; generating a reinforcement assembly sequence according to the photovoltaic system installation position distribution information and the reinforcement analysis model; generating a load distribution scheme based on the component sequence; and the distribution scheme and the reinforcement analysis model are combined, and the supporting node arrangement density and the connecting component material specification are determined through multi-objective optimization. According to the method, multi-load and structure aging are comprehensively considered, multi-target optimization is achieved, the safety and economical efficiency of the reinforcement scheme are improved, and the method is suitable for photovoltaic reinforcement calculation of the existing building roof.

The invention relates to the field of new energy, and discloses a photovoltaic system efficiency evaluation method and system based on unmanned aerial vehicle multi-source image fusion, and the method comprises the steps: collecting a visible light orthoimage, thermal imaging data and environment parameters of a photovoltaic system, and obtaining a registration result through employing an improved feature point matching algorithm; based on a registration result, combining spatial features of a visible light image and temperature features of thermal imaging, realizing accurate segmentation of the photovoltaic panel through a deep learning model, and identifying the type, the arrangement mode and the installation angle of the photovoltaic panel at the same time; establishing a mathematical model of the relation between the photovoltaic panel temperature distribution and the power generation efficiency, distinguishing the normal working temperature difference and the fault hot spot, and analyzing and determining the efficiency attenuation degree and the fault type of the photovoltaic system through a heat distribution mode. The method is accurate in image registration, good in data fusion effect, accurate in temperature anomaly detection and comprehensive in efficiency evaluation, and provides more efficient and accurate technical support for management and maintenance of the distributed photovoltaic system.

The invention provides an intelligent fault diagnosis method and system for a photovoltaic system. The method comprises the following steps: collecting multi-source heterogeneous operation parameter data of the photovoltaic system based on an intelligent sensor network and carrying out standardized preprocessing; local feature extraction is carried out on edge nodes, a frequency moment is calculated, data summary aggregation is carried out through a frequency moment optimization algorithm, and a fusion key feature vector set is constructed by using a multi-modal data fusion model; performing anomaly detection based on the normal behavior mode baseline, and generating an abnormal state alarm signal and a preliminary anomaly type indication; constructing a weighted graph model based on a system topological structure, constructing a fault association sub-graph by using an approximate spanning tree algorithm, accurately positioning a fault unit and diagnosing a fault type; and generating and executing a self-healing operation scheme according to the fault diagnosis conclusion. Through the distributed multi-modal data fusion and approximate spanning tree fault positioning technology, rapid and accurate diagnosis and autonomous recovery of the photovoltaic system fault are realized, and the system reliability and the operation efficiency are improved.

The invention relates to the technical field of data processing, and discloses a distributed energy storage coordination control method and device of a photovoltaic system. The method comprises the following steps: performing MPPT tracking processing on real-time power data of a component through an incremental conductance method to obtain a target adjustment instruction sequence; performing fluctuation characteristic analysis processing on the target adjustment instruction sequence through a time domain decomposition algorithm to obtain a power balance compensation amount; performing energy storage capacity configuration processing on the power balance compensation amount through a hierarchical control algorithm to obtain an energy storage unit distribution scheme; performing charging and discharging management processing on each energy storage unit in the energy storage unit distribution scheme through a power equalization algorithm to obtain an energy storage adjustment control quantity; and performing system cascade joint debugging processing on the energy storage adjustment control quantity and the target adjustment instruction sequence through a collaborative optimization algorithm to obtain a system operation control strategy. According to the invention, the efficiency and accuracy of distributed energy storage coordination control of the photovoltaic system are improved.

The invention belongs to the technical field of artificial intelligence, and relates to a distributed photovoltaic system abnormity monitoring and intelligent early warning method. Key parameters of the distributed photovoltaic system are collected at high frequency, noise filtering and signal normalization processing are carried out on data, then multi-domain feature extraction is carried out, anomaly detection is carried out through auto-encoder reconstruction error analysis, convolutional neural network feature classification and a single-class support vector machine, and an anomaly detection result is output. Establishing a multi-dimensional anomaly evaluation model, and synthesizing obtained evaluation results of all dimensions to obtain a final evaluation result; the method comprises the following steps: carrying out hierarchical classification to identify specific anomaly types, carrying out diagnosis of different types of anomalies, identification of typical anomalies and evaluation of fault severity, outputting the specific anomaly types and severity, and providing detailed diagnosis information for early warning decision making. The system state is comprehensively evaluated, corresponding measures are taken according to the grading early warning mechanism and the abnormity severity degree, and complete distributed photovoltaic system abnormity monitoring and intelligent early warning are formed.

A photovoltaic system has photovoltaic modules which can be arranged in a row and are mounted on a support frame. Adjacent photovoltaic modules with their support frames are connected to one another in an articulated manner by joints or hinges and can be transferred via a drive unit from a substantially extended and flat state into a pushed-together, compact state and vice versa.The support structure comprises a first pair of guide rails comprised of two guide rails arranged at a distance from one another. Arranged laterally on the photovoltaic modules and on the support frames, respectively, are freely rotatable impellers, the mutual spacing of which corresponds to the spacing of the mutually opposite guide rails, so that the photovoltaic modules with low rolling resistance in the direction of the guide rails can be spread out or moved together.

The invention relates to the technical field of voltage sensitivity photovoltaic stability regulation and control of a power distribution network, in particular to a multi-parameter photovoltaic grid-connected voltage stability control method, system equipment and a medium, and aims to improve the transient modeling precision by constructing a second-order equivalent transient model of a photovoltaic system and decoupling a mapping relation between phase-locked loop parameters and equivalent inertia and damping; quantifying a transient stability boundary under voltage disturbance based on a phase-locked loop sensitive parameter, and determining a photovoltaic power angle critical safety threshold; for the whole voltage fluctuation process, dynamically and cooperatively regulating and controlling phase-locked loop parameters according to the voltage and frequency of the power grid; equivalent damping and inertia suppression oscillation are enhanced in the voltage drop period, inertia acceleration recovery is reduced while high damping is maintained in the voltage recovery period, rated parameters are reset in the steady state, the transient stability of the system for coping with voltage sag is remarkably improved, and the risk of power angle instability is avoided.

The invention relates to the technical field of system optimization control, in particular to a photovoltaic cell parameter identification method and system based on a composite model. The method comprises the steps of obtaining real-time operation data of a photovoltaic cell, performing feature extraction, and generating preprocessed operation state data; calculating an initial parameter estimation value of the photovoltaic cell by adopting a single-diode model and a double-diode model, and generating an initial parameter sequence; performing parameter optimization by using a genetic algorithm and a particle swarm optimization algorithm to obtain an optimized photovoltaic cell parameter set; training an error compensation model of the long and short term memory network in combination with historical operation data, and correcting identification parameters; based on the optimized parameter set and the error compensation model, constructing a composite parameter identification model by adopting an adaptive fusion algorithm; and acquiring real-time monitoring data of the photovoltaic system, and calculating an optimal operation adjustment parameter. According to the invention, the photovoltaic cell parameter identification precision is improved, and the adaptability of the system to environmental changes is enhanced.

The invention provides a multi-scale photovoltaic power prediction method and system fusing numerical weather forecast and a physical information neural network, relates to the technical field of photovoltaic power prediction, and realizes rolling prediction of future meteorological parameters and horizontal radiation intensity through numerical weather forecast. The authenticity and the stability of the meteorological data are effectively improved by combining quantile mapping and cascade correction of the time sequence mode attention neural network; and through combined modeling of a physical information neural network and a time sequence characteristic network, meteorological and radiation data subjected to multi-level correction and conversion are deeply fused with a photovoltaic system physical law, and high-precision prediction of photovoltaic power is realized. The whole prediction process has automatic anomaly elimination and deletion complementation capabilities, the prediction robustness under complex meteorological conditions and extreme environments is enhanced, and the sequential response and physical consistency of photovoltaic power are optimized, so that the engineering applicability and intelligent level of the system are greatly improved.

The invention discloses a building roof photovoltaic panel arrangement method based on a live-action three-dimensional model. The method comprises the following steps: step 1, acquiring and modeling the live-action three-dimensional model; step 2, optimizing the live-action three-dimensional model; step 3, performing sunlight analysis based on the optimized live-action three-dimensional model; 4, extraction and priority division of effective arrangement areas of roofs: screening available areas of the roofs, calculating obstacle avoidance areas so as to determine effective arrangement areas, and performing priority division on the arrangement areas in combination with factors such as roof gradients, azimuth angles and obstacle density; and step 5, designing and realizing a spatial arrangement algorithm: calculating a minimum bounding rectangle of the preferential arrangement area, designing an arrangement grid, calculating position coordinates of the photovoltaic panels, performing arrangement verification on the panels, and finally realizing roof spatial arrangement of the photovoltaic panels. According to the invention, photovoltaic panel spatial arrangement of a complex building roof can be realized, and a new solution is provided for improving photovoltaic system efficiency and engineering feasibility.

The invention provides a distributed photovoltaic data acquisition method and device based on adaptive encryption communication and multi-link redundancy, and the method comprises the steps: collecting real-time power generation data, equipment state data and environment parameters of a photovoltaic system through a multi-source sensor, and forming original data; an MQTT over TLS adaptive encryption communication protocol is adopted to perform end-to-end encryption on original data, and dynamic key management is combined to ensure transmission security; based on a dynamic link selection algorithm, encrypted data is transmitted to a power master station through 4G and LoRaWAN double-link redundancy, so that the transmission reliability is improved; and the master station side decrypts the data and then integrates the data to a database to support power grid dispatching and predictive analysis. According to the invention, the problems of safety and reliability in distributed photovoltaic data acquisition are solved, and the method is suitable for a smart power grid monitoring scene with high reliability and high real-time performance requirements.

The invention relates to the technical field of inverter control, and discloses a micro inverter control method and system in a photovoltaic system and a storage medium. The method comprises the following steps: carrying out parameter acquisition and processing on the photovoltaic micro inverter to obtain an initial parameter set; designing a radial basis function neural network compensation uncertainty parameter based on the initial parameter set; inputting the compensation parameter set into a particle swarm optimization algorithm to optimize control parameters; and training a back propagation neural network based on the optimized parameter set to realize maximum power point tracking control. According to the method, the uncertainty of the system is compensated by introducing the radial basis function neural network, the control parameters are optimized in combination with the particle swarm optimization algorithm, and the real-time prediction and adjustment of the parameters are realized by using the back propagation neural network; the technical problems that a traditional control method is low in control precision and poor in adaptability when facing nonlinear system characteristics, environmental condition changes and parameter uncertainty are effectively solved.

The utility model relates to the technical field of floating photovoltaic systems, and discloses an offshore photovoltaic floating body and a connecting structure thereof, the offshore photovoltaic floating body comprises a floating body unit member, the two ends of the floating body unit member in the first direction are respectively provided with a connecting part, and the connecting parts are connected with the floating body unit member. Each connecting part comprises two embracing lugs protruding out of the end face of the corresponding floating body unit piece in the first direction, the two embracing lugs are oppositely arranged, a connecting gap is formed between the opposite faces of the two embracing lugs, and the connecting gap is used for installing a connecting piece fixed to the other floating body unit piece; reinforcing ribs are arranged on the opposite faces of the two holding lugs and the end faces of the floating body unit pieces respectively. According to the offshore photovoltaic floating body and the connecting structure thereof, the connecting parts with unique shapes are designed, the spaced double-lug structures can be simply inserted into the connecting parts, and reliable connection is realized by matching with the fasteners, so that the stress is more uniform when the floating body is subjected to impact force, the connecting parts are not easy to damage, the structural stability of a floating photovoltaic system is greatly improved, and the service life of the floating body is prolonged. And the maintenance cost is reduced.

The utility model is suitable for the technical field of solar cells, and provides a back contact solar cell, a photovoltaic assembly and a photovoltaic system, the back contact solar cell comprises a silicon substrate, the back surface of the silicon substrate is provided with a plurality of first doped regions and a plurality of second doped regions which are sequentially and alternately arranged along a first direction, the polarities of the first doped region and the second doped region are opposite, the adjacent first doped region and second doped region are electrically isolated through a groove, the groove comprises a side wall and a bottom surface, the side wall is provided with a plurality of first miniature pyramid structures, the bottom surface is provided with a plurality of second miniature pyramid structures, the first miniature pyramid structures correspond to a second direction, and the second direction corresponds to a third direction. The second micro pyramid structure corresponds to a third direction, and the third direction is perpendicular to the bottom face and intersects with the second direction. Through the arrangement, the light trapping effect between the first micro pyramid structure and the second micro pyramid structure is good, and the light reflectivity is reduced, so that the photoelectric conversion efficiency of the back contact solar cell is improved.

According to the active power distribution network'source-load-storage 'collaborative optimization scheduling method and system, an active power distribution network'source-load-storage' collaborative interaction operation model considering building thermal inertia is constructed and comprises a building detailed thermal dynamic model considering building thermal inertia, a wind power and photovoltaic system output model, a power distribution network operation model and an energy storage power station model. Then, an active power distribution network multi-objective optimization strategy considering building thermal inertia is designed; the invention relates to an active power distribution network'source load storage 'collaborative interaction optimization model considering building thermal inertia. The objective of the invention is to reduce the operation cost of a power distribution network and improve the new energy consumption. And finally, a POA-GWO-CSO algorithm is adopted to solve an active power distribution network multi-objective optimization strategy considering building thermal inertia. According to the invention, high-efficiency application of energy storage and local consumption of new energy can be promoted, and the operation economy of the active power distribution network is improved.

The invention discloses a photovoltaic system capacity configuration method and device based on power generation and power utilization matching, and the method comprises the steps: obtaining historical meteorological data which comprise dry-bulb temperature, relative humidity, solar radiation and wind speed; calculating a future power generation data sequence and a future power utilization data sequence according to the historical meteorological data; performing correlation analysis processing according to the historical meteorological data, the future power generation data sequence and the future power consumption data sequence to obtain a target influence factor; dividing the working scene according to the target influence factor to obtain a target working scene; performing power generation and power utilization matching processing according to the target working scene, and calculating a comprehensive benefit evaluation value; and determining a photovoltaic system capacity configuration result according to the plurality of comprehensive benefit evaluation values. According to the invention, the capacity configuration of the photovoltaic system is realized, and the accuracy, the energy utilization rate and the matching degree of power generation and power utilization are improved. The system can be widely applied to the technical field of photovoltaic systems.

The present invention relates to the technical field of photovoltaic tile installation. Disclosed is a BIPV photovoltaic tile that is easy to install and remove, the tile comprising a base, wherein a first fixed bracket is fixedly connected to the base, a placement frame is rotationally connected to the first fixed bracket, rotary frames are rotationally connected to the placement frame and are arranged symmetrically on two sides of the placement frame in a transverse direction, the placement frame and the rotary frames all are provided with a BIPV photovoltaic tile body, a second fixed bracket is fixedly connected to the base, and a support bracket for supporting the placement frame is rotationally connected to the second fixed bracket. According to the present invention, the placement frame is supported on the support bracket to form a stable triangular support structure. During a support process, a first wedge block automatically moves upward so as to secure the BIPV photovoltaic tile body within a corresponding placement slot, enhancing the overall stability and safety of the BIPV photovoltaic system; and during a folding and removal process, automatic unlocking can be achieved, simplifying an installation and adjustment process of the photovoltaic tile. As such, the present invention facilitates easy installation and removal without compromising the stability of the structure.

The invention relates to the technical field of wires and cables, and discloses a fire-resistant cable based on an overhead photovoltaic system, a braided ring in a fire-resistant flame-retardant layer is formed by winding flame-retardant crosslinked polyethylene fibers, air circulation is guaranteed by virtue of a large number of pores among ropes, and when the fire-resistant cable is burnt by flame, high-temperature gas enters the space of the braided ring, and then the braided ring is sealed. On the other hand, the liquid drainage rod is pulled through contraction traction force, the piston disc is promoted to extrude the flame-retardant liquid in the storage sleeve, after the liquid is sprayed out through the liquid drainage holes, one part of the liquid directly acts on a flame area for fire extinguishing and flame retarding, and the flame-retardant effect is achieved. Most of the materials are adsorbed and retained by the porous structure of the braided ring, are gradually decomposed at a continuous high temperature to release flame-retardant gas, and react with braided ring fibers to form a liquid-state and solid-state composite heat-insulating layer to fill tiny pores which are still remained after shrinkage, so that the integrity of a cable circuit at the initial stage of a fire disaster is guaranteed.

The embodiment of the invention provides a detection circuit and method of a photovoltaic system and the photovoltaic system. The photovoltaic system comprises a photovoltaic module; a bus of the photovoltaic module is grounded through the photovoltaic grounding module; the detection circuit comprises a detection assembly of which the first end is connected with a positive bus of the photovoltaic system, the second end is connected with a negative bus of the photovoltaic system, and the third end is grounded; the detection assembly is used for controlling connection or disconnection between any bus of the photovoltaic assembly and the ground; and the current detection device is connected with the positive bus and the negative bus of the photovoltaic module and is used for detecting the sum of the current of the positive electrode and the negative electrode of the photovoltaic module so as to carry out ground fault detection on the photovoltaic module. The method is used for achieving the effect of detecting the specific position of the grounding fault of the photovoltaic module.