7 results about "Potential induced degradation" patented technology

The utility model provides a potential induced degradation repairing device and a photovoltaic power generation system. The device is connected with the alternating current end of an inverter in the photovoltaic power generation system. The device comprises a rectification unit, a positive DC bus, a negative DC bus, a virtual neutral point, a first capacitor, a second capacitor, a third capacitor, a bus selection unit, a voltage regulation unit and a control unit. The control unit is connected with the rectification unit, the bus selection unit and the voltage regulation unit. The potential between the bus and the functional ground is increased through the voltage regulating unit and the bus selection unit, so that the potential to ground of the middle point BUSN or the alternating current end of the inverter is changed, and the potential to ground of the negative electrode or the positive electrode of the photovoltaic module is indirectly increased; the compatibility and reliability of the system are improved, the cost of the system is not increased, and centralized management and maintenance are facilitated.

Provided are a potential induced degradation (PID) repair circuit and PID repair method for a photovoltaic (PV) system. The PV system includes a solar cell module, an energy storage module, a direct current direct current (DCDC) boost circuit, and an inverter circuit; the PID repair circuit includes a DC power supply and an isolation circuit; after the DC power supply is processed by the isolation circuit, one end of the isolation circuit is connected to a positive terminal PV+ or a negative terminal PV- of the solar cell module, and another end of the isolation circuit is connected to a ground terminal PE; and a first switch is disposed on a connection path between the solar cell module and the energy storage module; PID repair is performed on the solar cell module by applying a negative voltage to the positive terminal PV+ of the solar cell module or a positive voltage to the negative terminal PV- of the solar cell module via the DC power supply; and a connection path between the solar cell module and the inverter circuit is disconnected during the PID repair. This application can prevent an internal short circuit caused by the inverter circuit during the PID repair, thereby effectively guaranteeing the operational safety of the PV system.

The invention relates to an adhesive film, a preparation method thereof and a photovoltaic module. The adhesive film is prepared from the following raw materials in parts by mass: 20 to 55 parts of base material monomer, 1 to 10 parts of curing agent, 12 to 40 parts of oligomeric resin, 5 to 10 parts of refraction particles, 0.1 to 5 parts of grafting auxiliary agent, 0.1 to 5 parts of hydrolysis-resistant auxiliary agent and 0.1 to 5 parts of PID (Potential Induced Degradation)-resistant auxiliary agent. The adhesive film provided by the invention can improve the water resistance and PID resistance of the photovoltaic module while having relatively high optical transmittance, so that the service life of the photovoltaic module is prolonged.

The invention relates to the technical field of attenuation detection of photovoltaic modules, and discloses a potential-induced attenuation detection method of a photovoltaic module, which comprises the following steps: by taking a module packaging layer of the photovoltaic module as a working electrode, measuring the ion mobility of the module packaging layer of the photovoltaic module with different potential-induced attenuation rates through a preset standard electrochemical measurement process; constructing a migration rate-attenuation rate correlation model of the photovoltaic module; measuring the ion mobility of the to-be-measured photovoltaic module through a preset standard electrochemical measurement process by taking the module packaging layer of the to-be-measured photovoltaic module as a working electrode; substituting the ion mobility of the to-be-detected photovoltaic module into the mobility-attenuation rate correlation model, and calculating a potential-induced attenuation rate quantized value of the to-be-detected photovoltaic module; and judging the attenuation grade of the to-be-detected photovoltaic module according to the grade judgment threshold range in which the quantized value of the potential-induced attenuation rate of the to-be-detected photovoltaic module falls. According to the method, quantitative rating of the PID fault degree of the photovoltaic module can be realized with relatively low cost and relatively high efficiency.

Embodiments of the present application provide a power supply system. By means of cascade of output ends of power supplies or DC-DC units, the output voltage is increased, the current between the power supplies or DC-DC units and DC-AC units is decreased, and the problems of costs and losses of cables from the power supplies or DC-DC units to the DC-AC units are solved. Moreover, the power supply system provided by the embodiments of the present application can also reduce the number of the cables from the power supplies or DC-DC units to the DC-AC units by means of cascade of the output ends of the power supplies or DC-DC units and input cascade of the DC-AC units, thereby reducing system costs. Moreover, in the power supply system provided by the embodiments of the present application, the input cascade and output isolation of the DC-AC units can reduce the specifications of a power conversion device. The problems of inadequate specifications and high cost of power conversion devices in existing industry are solved. In addition, the power supply system provided in some embodiments can also solve the problem of Potential Induced Degradation (PID) caused by a negative voltage of a battery plate to the ground when the system is running.

The application provides a power equipment defect identification method and system based on machine vision, relates to the technical field of equipment defect identification, and comprises the following steps: through an imaging device carried by a drone, standard electroluminescence images, standard infrared thermal images and standard visible light images of a target photovoltaic module string are collected and preprocessed under different time windows, and environmental parameters of each collection are recorded; visual defect features and attenuation gradient features in the standard electroluminescence images are analyzed, the standard infrared thermal images, the standard visible light images and electrical performance data are combined and verified, and a final diagnosis of potential induced degradation is obtained; for the photovoltaic module string diagnosed as having potential induced degradation, the evolution rate of the potential induced degradation is evaluated by using a time series analysis method based on the environmental parameters, and a risk level of the potential induced degradation is mapped and generated; and a structured defect identification report is generated. The accuracy of power equipment defect identification is improved.

The invention discloses a photovoltaic coating, a photovoltaic cell, a photovoltaic module and a preparation method of the photovoltaic cell. The photovoltaic coating is formed by curing a composition comprising the following components in parts by weight: 45-55 parts of a prepolymer; 25 to 35 parts of a reactive diluent; 3 to 5 parts of a photoinitiator; and 2-4 parts of an ultraviolet light absorber. According to the invention, by directly forming the coating with ultraviolet ray isolation and high light transmittance on the surface of the battery piece, excellent ultraviolet ray protection is provided for the battery piece while the performance of the packaging adhesive film is not influenced, and a potential induced degradation (PID) effect induced by ultraviolet ray radiation is synergistically inhibited. The coating composition for forming the photovoltaic coating is optimized and can be quickly cured in an air atmosphere, so that the production efficiency is greatly improved, and the dependence on inert gas is reduced; meanwhile, precise coating processes such as ink-jet printing and the like are adopted, so that the high utilization rate of the material is realized, and the manufacturing cost is remarkably reduced.