Power supply cabinet specially used for photovoltaic direct current arc fault protection electric appliance detection equipment

Abstract

The utility model discloses a power supply cabinet specially used for photovoltaic direct current arc fault protection electric appliance detection equipment. The power supply cabinet comprises a cabinet body frame and a mechanical supporting part arranged in the cabinet body frame. The mechanical supporting part comprises a plurality of side cross beams arranged on the side faces of the cabinet body frame, a plurality of supporting cross beams penetrating through the interior of the cabinet body frame and transversely arranged between the two side cross beams, and a plurality of side vertical beams vertically arranged on the side cross beams. A plurality of element mounting plates are arranged on the mechanical supporting part and are used for mounting elements for providing a power supply circuit; an embedded assembly component is arranged on the supporting cross beam, and the embedded assembly component comprises a photovoltaic simulation source module and a decoupling network module. The photovoltaic simulation source module and the decoupling network module are arranged in the power supply cabinet, after an alternating current power supply is connected, coupling and interference between circuits of the photovoltaic simulation source module are eliminated, and reliable direct current output is provided for photovoltaic direct current arc fault protection electric appliance detection equipment.

Description

Technical Field

[0001] The utility model relates to the technical field of photovoltaic power generation detection, in particular to a power supply cabinet specially used for photovoltaic DC arc fault protection electrical appliance detection equipment. Background Art

[0002] With the increasing shortage of renewable energy around the world, my country has paid more attention to the development and utilization of renewable energy. There are many types of renewable energy, and solar energy has attracted the attention of various countries due to its advantages of low pollution, safety, and abundant resources. Among them, photovoltaic power generation is the main way to develop and utilize solar energy. Photovoltaic power generation is a technology that uses the photovoltaic effect of semiconductor interfaces to directly convert light energy into electrical energy.

[0003] However, due to the rapid development of the photovoltaic industry in recent years and the aging of photovoltaic power stations, the frequency of faults in photovoltaic systems has become increasingly high. The DC output voltage of the photovoltaic system increases with the increase of photovoltaic strings, and can reach up to thousands of volts. In a DC system, the current does not have a zero crossing point, and an arc can be generated in the system when the DC voltage is greater than 11V or its current exceeds 1A. At the same time, the photovoltaic components continue to generate electricity after the fault occurs, which further maintains the burning of the arc. In a photovoltaic system, once a DC fault arc occurs, if effective protective measures are not taken in time, a high temperature of more than 3000℃ will be generated, which will cause a fire. In addition, compared with traditional systems, photovoltaic systems are more affected by light intensity, temperature, inverter noise, etc., making fault arcs in photovoltaic systems more difficult to detect.

[0004] In order to avoid the serious consequences of arc faults as much as possible, Underwriter-Laboratories-Inc developed the first version of UL 1699B standard in 2018 to evaluate the effectiveness of arc fault detection methods in photovoltaic DC systems. The National Electrical Code (NEC) 690.11 implemented in 2011 requires that DC arc fault detection devices and photovoltaic DC arc fault protection devices must be installed in photovoltaic systems with DC voltage greater than 80V. Photovoltaic DC arc fault protection devices are a type of protection device that disconnects the power circuit before the arc fault develops into a fire or a short circuit occurs in the circuit by identifying the characteristic signal of the arc fault in the circuit.

[0005] Based on the above situation, the reliability detection of photovoltaic DC arc fault protection devices is particularly important. However, there are very few detection devices for photovoltaic DC arc fault protection devices on the market, and they have single functions and can only perform single line structures. The degree of automation is low and the test accuracy is not high, which seriously affects the accuracy of the test and creates safety hazards.

[0006] Therefore, a photovoltaic DC arc fault protection electrical appliance detection device is needed to solve the problems of low automation and low test accuracy of arc fault detection in the prior art, and provide testing and data support for photovoltaic DC arc fault protection electrical appliances. However, since solar panels have too high requirements for weather and cannot provide stable power supply, and it is impossible to place a large number of solar cell arrays in the laboratory, it is necessary to design a corresponding photovoltaic power supply product to replace the solar panel to provide power for the entire detection equipment. Therefore, the design of the photovoltaic power supply product is directly related to the detection direction and detection capability of the entire detection equipment. Utility Model Content

[0007] The technical problem to be solved by the utility model is to provide a power supply cabinet specially used for photovoltaic DC arc fault protection electrical appliance detection equipment, which is used to replace the solar cell panel to provide analog power to the entire detection equipment.

[0008] In order to solve the above technical problems, the technical solutions provided by the utility model are as follows:

[0009] The present invention provides a power supply cabinet specially used for photovoltaic DC arc fault protection electrical appliance detection equipment, comprising a cabinet frame and a mechanical support part arranged in the cabinet frame, the cabinet frame and the mechanical support part are respectively provided with mounting holes arranged according to the module number, and the mechanical support part is assembled on the cabinet frame through the mounting holes;

[0010] The mechanical support part includes a number of side beams arranged on the side of the cabinet frame, a number of supporting beams that pass through the interior of the cabinet frame and are horizontally arranged between two side beams, and a number of side vertical beams that are vertically arranged on the side beams; a number of component mounting plates are arranged on the mechanical support part for installing components that provide power supply circuits; an embedded assembly component is arranged on the supporting beam, and the embedded assembly component includes a photovoltaic simulation source module and a decoupling network module.

[0011] Furthermore, the decoupling network module adopts a modular design, and the components of the decoupling network module include air-core inductors, common-mode inductors and circuit boards with capacitors of various specifications.

[0012] Furthermore, the decoupling network module is installed in an embedded drawer structure, and a handle is provided on the outer side thereof.

[0013] Furthermore, the photovoltaic simulation source module simulates the effect of photovoltaic power generation by converting alternating current into controllable direct current output.

[0014] Furthermore, movable casters are fixedly installed at the four corners of the bottom of the cabinet frame; a top plate is fixedly installed on the top of the cabinet frame; a rear door with a double-door structure is symmetrically arranged on the rear side of the cabinet frame, and a shutter that can dissipate heat and is waterproof is opened on the rear door; side sealing plates are arranged on the left and right sides of the cabinet frame.

[0015] Furthermore, a front cover plate is provided on the front of the cabinet frame, including an upper cover plate and a lower cover plate, the upper cover plate is a whole cover plate fixedly arranged, and the lower cover plate is provided with a plurality of rectangular openings for installing modular photovoltaic simulation source modules and decoupling network modules.

[0016] Furthermore, the lower sealing plate is provided with three openings for accommodating photovoltaic simulation source modules and three openings for accommodating decoupling network modules.

[0017] Furthermore, the side cross beams and side vertical beams are C-shaped structures, and the three sides of the C-shaped structure are respectively provided with mounting holes arranged according to a preset pattern; the supporting cross beam is C-shaped structure, and its top surface is provided with mounting holes arranged according to a preset pattern.

[0018] Furthermore, the component mounting plate is an overall C-shaped structure, which is formed by integrally bending a cold-rolled plate.

[0019] Compared with the prior art, the power supply cabinet provided by the utility model for photovoltaic DC arc fault protection electrical appliance detection equipment has the following beneficial effects:

[0020] The power cabinet is equipped with a photovoltaic simulation source module and a decoupling network module. After being connected to an AC power supply, the coupling and interference between the circuits of each module of the photovoltaic simulation source are eliminated, and a DC output with a steady voltage and constant current is provided for the photovoltaic DC arc fault protection electrical detection equipment.

[0021] The entire cabinet frame of the power cabinet has regularly arranged mounting holes. Therefore, bolt connections can be used for the installation and connection of the overall frame, the mechanical support part, and the component fixing plate. There is no need for welding, and the installation flexibility is high. The GGD cabinet has high versatility. When certain components are eliminated, the GGD cabinet has good installation flexibility and will not cause installation problems due to the modification or update of components. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of the structure of a power supply cabinet provided in an embodiment of the utility model for use with photovoltaic DC arc fault protection electrical appliance detection equipment;

[0023] Figure 2 A schematic diagram of the structure of a power supply cabinet provided in an embodiment of the utility model and used for photovoltaic DC arc fault protection electrical appliance detection equipment, with the side sealing plate removed;

[0024] Figure 3 A schematic diagram of the front structure of a power supply cabinet specially used for photovoltaic DC arc fault protection electrical appliance detection equipment provided by an embodiment of the utility model;

[0025] Figure 4 A schematic diagram of the side structure of a power supply cabinet specially used for photovoltaic DC arc fault protection electrical appliance detection equipment provided by an embodiment of the utility model;

[0026] Figure 5 A schematic diagram of a circuit in a power cabinet provided by an embodiment of the utility model for use with a photovoltaic DC arc fault protection electrical appliance detection device;

[0027] Figure 6 A topological structure diagram of the decoupled network module provided in an embodiment of the utility model.

[0028] Description of main reference numerals:

[0029] 1-cabinet frame; 101-top long beam; 102-top short beam; 103-column; 104-bottom long beam; 105-bottom short beam; 106-rear door; 107-mobile casters; 108-top plate; 109-front cover plate; 1091-upper cover plate; 1092-lower cover plate; 110-side cover plate; 2-mechanical support part; 21-side cross beam; 22-side vertical beam; 23-support cross beam; 3-photovoltaic simulation source module; 4-decoupling network module; 5-handle; 6-component mounting plate; 7-terminal fixing plate. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0031] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "front", "back", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0032] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, an integral connection, or a detachable connection; it can be the internal connection of two components; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] See also Figure 1-Figure 5 The embodiment of the utility model provides a power supply cabinet specially used for photovoltaic DC arc fault protection electrical appliance detection equipment, the power supply cabinet comprises a cabinet frame 1 and a mechanical support part 2 arranged in the cabinet frame 1, the mechanical support part 2 is used to fix and support the components used to provide the power supply circuit. The cabinet frame 1 is respectively provided with mounting holes arranged according to the module, that is, the mounting holes are arranged according to the predetermined size rule, and the mechanical support part 2 is assembled on the cabinet frame 1 through the mounting holes.

[0034] The structure of the cabinet frame 1 includes a group of top long beams 101, top short beams 102, columns 103, bottom long beams 104, and bottom short beams 105. The top long beams 101, top short beams 102, columns 103, bottom long beams 103, and bottom short beams 105 are respectively provided with mounting holes arranged according to the module, so as to improve the versatility of product assembly. Therefore, the top long beams 101, top short beams 102, bottom long beams 104, and bottom short beams 105 can be connected with the columns 103 by bolt connection without welding, so that the installation is stable, the structure is reliable, and the maintenance is convenient.

[0035] The bottom of the cabinet frame 1 is fixed with movable casters 107 at the four corners; the top of the cabinet frame 1 is fixed with a top plate 108; the rear side of the cabinet frame 1 is symmetrically provided with a double-door structure rear door 106, and the rear door 106 is provided with a heat-dissipating and waterproof shutter, and the rear door 106 is connected to the cabinet frame 1 with a galvanized shaft hinge for installation, which is easy to disassemble; side sealing plates 110 are provided on the left and right sides of the cabinet frame 1, and the panel of the entire cabinet frame 1 adopts a spraying process, which has strong adhesion and good texture. The whole cabinet is matte in color, avoiding the dazzling effect, creating a more comfortable visual environment for the staff. The front of the cabinet frame 1 is provided with a front sealing plate 109, which is a box-shaped structure as a whole, formed by bending a cold-rolled plate in one piece, and the installation method is embedded installation. The front sealing plate 109 includes an upper sealing plate 1091 and a lower sealing plate 1092 . The upper sealing plate 1091 is a whole sealing plate fixedly arranged, and the lower sealing plate 1092 is provided with a plurality of rectangular openings for installing modular photovoltaic simulation source modules 3 and decoupling network modules 4 .

[0036] The mechanical support part 2 includes a plurality of side cross beams 21 disposed between two upright posts 103 on the side of the cabinet frame 1, a plurality of support cross beams 23 penetrating the interior of the cabinet frame 1 and disposed horizontally between the two side cross beams 21, and a plurality of side vertical beams 22 vertically disposed on the side cross beams 21, specifically:

[0037] The side crossbeam 21 is a C-shaped structure, and the three sides of the C-shaped structure are respectively provided with mounting holes arranged according to the module E=20mm, and the diameter of the mounting holes is 10mm, which are used to install the supporting crossbeam 23 and strengthen the strength of the cabinet frame 1; a terminal fixing plate 7 is also provided on the side crossbeam 21, and the terminal fixing plate is used to fix the terminal.

[0038] The side vertical beam 22 is in a C-shaped structure, and the three sides of the C-shaped structure are respectively provided with mounting holes arranged in a module of E=20mm, and the diameter of the mounting holes is 10mm, which is used to realize the installation of the components to be installed in the vertical direction, such as for installing the component mounting plate 6. The component mounting plate 6 is in a C-shaped structure as a whole, and is formed by bending a cold-rolled plate in one piece, and is installed in a hanging manner, and is used to install various secondary wiring components, such as contactors, relays or circuit breakers.

[0039] The supporting crossbeam 23 is of C-shaped structure, and its top surface is provided with mounting holes arranged according to E=45 mm, and the diameter of the mounting holes is 10 mm, which is used to carry heavier embedded assembly components, such as photovoltaic simulation source module 3, decoupling network module 4, etc.

[0040] The side beam 21 is installed between two adjacent columns 103 on the upper side of the cabinet frame 1 through the installation holes, and the two ends of the support beam 23 are installed on the side beam 21 through the installation holes; the mechanical support part 2 can realize the installation of components to be installed at any position through the combination of a plurality of side beams 21, a plurality of side vertical beams 22 and a plurality of support beams 23. The photovoltaic power supply cabinet has good installation flexibility in mechanical structure and high versatility. Even if the main body eliminates a certain product in the future, the GGD (fixed wiring low-voltage distribution cabinet, G--low-voltage distribution cabinet; G--fixed installation, fixed wiring; D--electricity cabinet) type cabinet has good installation flexibility, and will not cause installation troubles due to the modification or update of components.

[0041] In this embodiment, the support beams 23 are provided in three groups, each group carrying a photovoltaic simulation source module 3 and a decoupling network module 4. Further, the lower cover plate 1092 is provided with three rectangular windows corresponding to the photovoltaic simulation source module 3, and three rectangular windows corresponding to the decoupling network module 4. Among them, a transformer fixing plate is also provided on the bottom support beam 23, and a transformer is provided on the fixing plate.

[0042] The design of the decoupling network module 4 is based on the topological relationship diagram specified in the national standard, see Figure 6 , specific parameters and characteristics are given to each component such as the air-core inductor, common-mode inductor, and circuit board with capacitors in the topological diagram, so that it can meet the detection of more different photovoltaic DC arc fault protection appliances and different test circuit structures. And modular design is carried out, and a universal disassembly structure and components are adopted to increase the compatibility and operability of the decoupling network module 4. The installation of the decoupling network module 4 adopts an embedded drawer structure, which is neat and beautiful, and a handle 5 is provided on the outside for easy disassembly and assembly.

[0043] In addition to the decoupling network module 4 and the photovoltaic simulation source module 3, the power cabinet also includes some electrical components such as isolation transformers, power main switches, control circuit switches, several DC relays, aviation plugs, photovoltaic connectors, transformers, circuit breakers, etc. that constitute the control loop. The parameters of the decoupling network module 4 are set as shown in the following table:

[0044] parameter Parameter Value Remark Capacitor C1 Not less than 20μF The decoupling capacitor parameter determines the output value of the DC source Capacitor C2, Capacitor C3 22nF Bypass capacitor Inductor L1 12mH Common mode filter inductor Inductor L2, Inductor L3 Not less than 60μH Air core inductor to avoid saturation

[0045] In short, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A power supply cabinet specially used for photovoltaic DC arc fault protection electrical equipment detection equipment, characterized in that: It comprises a cabinet frame (1) and a mechanical support part (2) arranged in the cabinet frame, the cabinet frame and the mechanical support part are respectively provided with mounting holes arranged according to modules, and the mechanical support part is assembled on the cabinet frame through the mounting holes; The mechanical support part comprises a plurality of side crossbeams (21) arranged on the side of the cabinet frame, a plurality of support crossbeams (23) penetrating the interior of the cabinet frame and arranged horizontally between two side crossbeams, and a plurality of side vertical beams (22) arranged vertically on the side crossbeams; the mechanical support part is provided with a plurality of component mounting plates for mounting components for providing a power supply circuit; the support crossbeam is provided with an embedded assembly component, and the embedded assembly component comprises a photovoltaic simulation source module (3) and a decoupling network module (4).

2. The power supply cabinet specially used for photovoltaic DC arc fault protection electrical appliance detection equipment according to claim 1 is characterized in that: The decoupling network module adopts a modular design, and the components of the decoupling network module include air-core inductors, common-mode inductors and circuit boards with capacitors of various specifications.

3. The power supply cabinet specially used for photovoltaic DC arc fault protection electrical appliance detection equipment according to claim 2 is characterized in that: The decoupling network module is installed using an embedded drawer structure, and a handle (5) is provided on the outer side thereof.

4. The power supply cabinet specially used for photovoltaic DC arc fault protection electrical appliance detection equipment according to claim 1 is characterized in that: The photovoltaic simulation source module simulates the effect of photovoltaic power generation by converting alternating current into controllable direct current output.

5. The power supply cabinet specially used for photovoltaic DC arc fault protection electrical appliance detection equipment according to claim 1 is characterized in that: The bottom of the cabinet frame is fixedly provided with movable casters (107) at the four corners; the top of the cabinet frame is fixedly provided with a top plate (108); a rear door (106) of a double-door structure is symmetrically provided on the rear side of the cabinet frame, and a shutter is provided on the rear door; and side sealing plates (110) are provided on the left and right sides of the cabinet frame.

6. The power supply cabinet specially used for photovoltaic DC arc fault protection electrical appliance detection equipment according to claim 1 is characterized in that: The front of the cabinet frame is provided with a front sealing plate (109), including an upper sealing plate (1091) and a lower sealing plate (1092), wherein the upper sealing plate is a whole sealing plate fixedly arranged, and the lower sealing plate is provided with a plurality of rectangular openings for installing modular photovoltaic simulation source modules and decoupling network modules.

7. The power supply cabinet specially used for photovoltaic DC arc fault protection electrical appliance detection equipment according to claim 6 is characterized in that: The lower sealing plate is provided with three openings for accommodating photovoltaic simulation source modules and three openings for accommodating decoupling network modules.

8. The power supply cabinet specially used for photovoltaic DC arc fault protection electrical appliance detection equipment according to claim 1, characterized in that: The side cross beams and side vertical beams are C-shaped structures, and the three sides of the C-shaped structure are respectively provided with mounting holes arranged according to a preset pattern; the supporting cross beam is C-shaped structure, and its top surface is provided with mounting holes arranged according to a preset pattern.

9. The power supply cabinet specially used for photovoltaic DC arc fault protection electrical appliance detection equipment according to claim 1, characterized in that: The component mounting plate is in a C-shaped structure as a whole and is formed by integrally bending a cold-rolled plate.

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