Photovoltaic direct current switch with over-temperature protection function and photovoltaic system

Abstract

The utility model belongs to the field of photovoltaic systems, and particularly relates to a photovoltaic direct-current switch with an over-temperature protection function and a photovoltaic system. The temperature sensor detection module is arranged on the photovoltaic direct-current switch body and is used for detecting the temperature of the photovoltaic direct-current switch body and outputting a temperature signal; the comparison module is used for receiving the temperature signal, comparing the temperature signal with a preset temperature threshold signal, and outputting an execution signal when judging that the temperature corresponding to the signal transmitted by the temperature sensor exceeds a temperature threshold; and the protection action execution module is arranged on the photovoltaic direct-current switch body, and when the protection action execution module receives the execution signal, the protection action execution module outputs a protection action to drive the photovoltaic direct-current switch body in the switching-on state to be switched to the switching-off state. By detecting the temperature of the photovoltaic direct-current switch, the function of automatically switching off the switch when the switch is over-temperature is achieved, the problem of protection of the photovoltaic direct-current switch in a photovoltaic system is solved, and the cost is low.

Description

Technical Field

[0001] This utility model belongs to the field of photovoltaic systems, specifically relating to a photovoltaic DC switch and photovoltaic system with over-temperature protection function. Background Technology

[0002] With the rise of the new energy industry, combiner boxes and string inverters are being used more and more. These systems typically have a built-in photovoltaic DC switch to cut off power to the photovoltaic panels during installation and maintenance, ensuring the safety of users and other personnel. Overcurrent protection for the box relies on fuses. However, currently available string inverters often diagnose faults in the inverter's electronic or DC high-voltage circuitry. When the current flowing through the photovoltaic DC switch is too high, the fuse fuse element may fail, resulting in high repair costs. Utility Model Content

[0003] The purpose of this invention is to overcome the shortcomings and deficiencies of the existing technology and to provide a photovoltaic DC switch and photovoltaic system with over-temperature protection function.

[0004] The technical solution adopted by this utility model is as follows: A photovoltaic DC switch with over-temperature protection function, comprising a photovoltaic DC switch body, wherein the photovoltaic DC switch body has an open state and a closed state; and further comprising,

[0005] A temperature sensor detection module is installed on the photovoltaic DC switch body to detect the temperature of the photovoltaic DC switch body and output a temperature signal;

[0006] The comparison module, connected to the temperature sensor detection module, is used to receive temperature signals and compare them with preset temperature threshold signals. When it is determined that the temperature corresponding to the signal from the temperature sensor exceeds the temperature threshold, an execution signal is output.

[0007] The protection action execution module is installed on the photovoltaic DC switch body and connected to the comparison module. When the protection action execution module receives the execution signal, the protection action execution module outputs the protection action, driving the photovoltaic DC switch body, which is in the closed state, to switch to the open state.

[0008] The temperature sensor detection module has a temperature sensing point set on the outer surface of the photovoltaic DC switch body near the wiring terminals.

[0009] A photovoltaic DC switch body includes several switching units that operate synchronously on and off. The temperature sensor detection module is provided with temperature sensing points on the outer surface of some or all of the switching units of each photovoltaic DC switch body.

[0010] The photovoltaic DC switch body has an energy storage mechanism, which has an energy storage state and an energy release state. When the energy storage device is in the energy storage state, the photovoltaic DC switch body can normally switch between the open state and the closed state. When the energy storage device switches from the energy storage state to the energy release state, it drives the photovoltaic DC switch body, which is in the closed state, to switch to the open state.

[0011] The protection action execution module works in conjunction with the energy storage mechanism. When the protection action execution module receives an execution signal, it drives the energy storage mechanism to switch from the energy storage state to the energy release state.

[0012] The protection action execution module is an electromagnetic drive device, and the execution signal is an electrical signal that powers on the electromagnetic drive device.

[0013] A voltage module is provided, which is used to convert the high-voltage DC power output of the photovoltaic power source into a low-voltage DC output.

[0014] It also includes an over-temperature protection box for housing the comparison module;

[0015] The temperature sensor detection module includes a temperature sensor and a temperature signal transmission line. The temperature sensor is connected to the over-temperature protection box through the temperature signal transmission line.

[0016] The over-temperature protection box is detachably connected to the outer wall of the photovoltaic DC switch body. The temperature sensor detection module has a temperature sensing point on the outer wall of the photovoltaic DC switch body near the over-temperature protection box. The temperature signal transmission line is connected to the outer wall of the over-temperature protection box near the photovoltaic DC switch body, and the outer wall of the over-temperature protection box near the photovoltaic DC switch body has a take-up groove to accommodate the temperature signal transmission line.

[0017] The temperature sensor detection module includes at least two temperature sensor junction boxes;

[0018] One temperature sensor box corresponds to one photovoltaic DC switch body. Each temperature sensor box is connected to several temperature sensors through a first temperature signal transmission line, and the several temperature sensors are respectively set at different positions of the corresponding photovoltaic DC switch body.

[0019] It also includes an over-temperature protection power supply box, which houses the comparison module and is connected to at least two temperature sensor boxes via the second temperature signal transmission line, for receiving temperature signals output by the connected temperature sensors.

[0020] A photovoltaic system including a photovoltaic DC switch body with over-temperature protection function as described above, comprising:

[0021] Photovoltaic power panels are used to output high-voltage DC power.

[0022] The photovoltaic DC switch body is connected to the photovoltaic power board and is used to control the on / off of the high-voltage DC power output by the photovoltaic power board.

[0023] The comparison module is connected to the high-voltage DC power output from the photovoltaic power panel.

[0024] The beneficial effects of this utility model are as follows: This utility model detects the temperature of the photovoltaic DC switch and enables the switch to automatically disconnect when it overheats, thus solving the problem of photovoltaic DC switch protection in photovoltaic systems, and at a low cost. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, obtaining other drawings based on these drawings without creative effort still falls within the scope of this utility model.

[0026] Figure 1 This is a schematic diagram of one embodiment of the present invention;

[0027] Figure 2 This is a schematic diagram of the structure of one embodiment of the present utility model;

[0028] Figure 3 This is an exploded view of one embodiment of the present invention;

[0029] Figure 4 This is a schematic diagram of the assembly structure of one embodiment of the present invention;

[0030] Figure 5 This is a schematic diagram of another embodiment of the present invention;

[0031] Figure 6 This is a schematic diagram of the structure of the photovoltaic DC switch body and the temperature sensor detection module in another embodiment of the present invention.

[0032] In the diagram, the components are: photovoltaic DC switch body - 100, temperature sensor detection module - 200, temperature sensor - 210, temperature sensor junction box - 240, second temperature signal transmission line - 250, comparison module - 300, over-temperature protection box - 310, cable tray - 311, over-temperature protection power supply box - 320, power input line - 330, execution signal output line - 340, execution signal output female terminal - 341, execution signal output male terminal - 342, inverter interface - 350, protection action execution module - 400, protection action execution module interface - 410, and voltage module - 500. Detailed Implementation

[0033] To make the objectives, technical solutions and advantages of this utility model clearer, the utility model will be described in further detail below with reference to the accompanying drawings.

[0034] It should be noted that all uses of "first" and "second" in the embodiments of this utility model are for the purpose of distinguishing two entities or parameters with the same name but different names. It is clear that "first" and "second" are only for the convenience of expression and should not be construed as limiting the embodiments of this utility model. Subsequent embodiments will not explain this in detail.

[0035] The directional and positional terms used in this utility model, such as up, down, front, back, left, right, inside, outside, top, bottom, side, etc., are only for reference to the accompanying drawings. Therefore, the directional and positional terms used are for the purpose of explaining and understanding this utility model, and not for limiting the scope of protection of this utility model.

[0036] like Figure 1 As shown, the photovoltaic system includes a photovoltaic power supply board 600 and a photovoltaic DC switch body 100. The photovoltaic power supply board 600 outputs photovoltaic high-voltage DC power. The photovoltaic DC switch body 100 is installed on the output circuit of the photovoltaic power supply board 600 and has an open state and an closed state. It is used to control the on and off of the high-voltage DC power output by the photovoltaic power supply board 600 so as to cut off the photovoltaic power supply during installation and maintenance.

[0037] This invention enables the aforementioned photovoltaic DC switch body 100 to possess over-temperature protection functionality, thereby achieving over-temperature protection. Specifically, this invention includes a temperature sensor detection module 200, a comparison module 300, and a protection action execution module 400. The temperature sensor detection module 200 is disposed on the photovoltaic DC switch body 100 and is used to detect the temperature of the photovoltaic DC switch body 100 and output a temperature signal. The comparison module 300 is connected to the temperature sensor detection module 200 and is used to receive the temperature signal and compare the temperature signal with a preset temperature threshold signal. When it is determined that the temperature corresponding to the signal from the temperature sensor exceeds the temperature threshold, an execution signal is output. The protection action execution module 400 is disposed on the photovoltaic DC switch body 100 and is connected to the comparison module 300. When the protection action execution module 400 receives the execution signal, the protection action execution module 400 outputs a protection action, driving the photovoltaic DC switch body 100, which is in the closed state, to switch to the open state, thereby cutting off the power supply to the photovoltaic panel due to over-temperature and protecting the photovoltaic DC switch body 100.

[0038] In some embodiments of this utility model, the temperature sensor used in the temperature sensor detection module 200 can be a thermistor, and the change in the current signal passing through it corresponds to the temperature signal.

[0039] In some embodiments of this utility model, the comparison module 300 uses a microcontroller to compare temperature signals and output an execution signal when it is determined that the temperature corresponding to the signal transmitted by the temperature sensor exceeds the temperature threshold.

[0040] In some embodiments of this utility model, the photovoltaic DC switch body 100 has an energy storage mechanism, which has an energy storage state and an energy release state. When the energy storage device is in the energy storage state, the photovoltaic DC switch body 100 can normally switch between the open state and the closed state. When the energy storage device switches from the energy storage state to the energy release state, it drives the photovoltaic DC switch body 100, which is in the closed state, to switch to the open state. The protection action execution module 400 cooperates with the energy storage mechanism. When the protection action execution module 400 receives the execution signal, it drives the energy storage mechanism to switch from the energy storage state to the energy release state. The energy storage mechanism enables rapid circuit breaking, ensuring reliable and swift operation. Specifically, the structure of the energy storage mechanism releasing energy to drive the automatic circuit breaking of the switch is existing technology, and can be referenced to the structures disclosed in prior patents CN202310606424.1, CN202111031928.2, CN202110444990.8, CN202110382428.7, and CN202110292185.8. In some embodiments of this utility model, the protection action execution module 400 is an electromagnetic drive device, and the execution signal is an electrical signal that energizes the electromagnetic drive device.

[0041] In some embodiments of this utility model, the operation of the temperature sensor detection module 200 and the comparison module 300, and the execution of the protection action execution module 400 are powered by the high-voltage DC power output from the photovoltaic power panel 600, which is convenient for application.

[0042] In some embodiments of this invention, a voltage module 500 is provided, which is used to convert the high-voltage DC power output of the photovoltaic power supply into a low-voltage DC output. The high-voltage DC power output by the photovoltaic power board 600 is typically 300-1500V. In some embodiments of this invention, a flyback power supply is specifically used. By using one input photovoltaic voltage, an 8-36Vdc output is generated. This output is then fed into a microcontroller via a DC-DC circuit. The microcontroller detects the temperature of the photovoltaic DC switch body 100. When the temperature exceeds a threshold, it controls the output of 8-36Vdc to the coil of the electromagnetic drive device, causing the switch to trip and thus protecting the switch.

[0043] In some embodiments of this utility model, the temperature sensor detection module 200 has a temperature sensing point set on the outer surface of the photovoltaic DC switch body 100 near the wiring terminal.

[0044] Preferably, a photovoltaic DC switch body 100 includes several switching units that operate synchronously on and off. The temperature sensor detection module 200 provides temperature sensing points on the outer surface of some or all of the switching units of each photovoltaic DC switch body 100.

[0045] Figure 2-4 In one specific embodiment of this utility model, an over-temperature protection box 310 is further included to house the comparison module 300. The over-temperature protection box 310 is connected to the outer wall of the photovoltaic DC switch body 100, forming a single device. The temperature sensor detection module 200 includes a temperature sensor 210 and a temperature signal transmission line. The temperature sensor 210 is connected to the over-temperature protection box 310 via the temperature signal transmission line. Specifically, the over-temperature protection box 310 can be detachably connected to the outer wall of the photovoltaic DC switch body 100, using common connection methods such as adhesive bonding, bolt connection, or snap-fit ​​connection. In some embodiments of this utility model, adhesive bonding is used, allowing direct compatibility with all commercially available disconnect switches with remote control tripping functions without altering the switch body structure. The temperature sensor detection module 200 has a temperature sensing point on the outer wall of the photovoltaic DC switch body 100 near the over-temperature protection box 310. The temperature sensor 210 is attached to the temperature sensing point. The temperature signal transmission line is connected to the outer wall of the over-temperature protection box 310 near the photovoltaic DC switch body 100, and the outer wall of the over-temperature protection box 310 near the photovoltaic DC switch body 100 has a take-up groove 311 for accommodating the temperature signal transmission line. Figure 2 As shown, after assembly, there will not be many exposed wires.

[0046] The over-temperature protection box 310 is equipped with a power input line 330, which is connected to 300-1500V. The voltage module 500 is built into the over-temperature protection box 310, where voltage conversion is performed and then sent to the comparison module 300.

[0047] The over-temperature protection box 310 is equipped with an execution signal output male terminal 342 and an execution signal output female terminal 341 connected via an execution signal output line 340, for outputting execution signals, which can be selected as needed. In the figure, the photovoltaic DC switch body 100 is equipped with a protection action execution module interface 410, which is connected to the execution signal output female terminal 341.

[0048] Figure 5-6In another specific embodiment of this utility model, the temperature sensor detection module 200 includes at least two temperature sensor junction boxes 240; each temperature sensor junction box 240 corresponds to one photovoltaic DC switch body 100, and each temperature sensor junction box 240 is connected to several temperature sensors 210 via a first temperature signal transmission line, with the several temperature sensors 210 respectively located at different positions on the corresponding photovoltaic DC switch body 100; it also includes an over-temperature protection power supply box 320, which houses the comparison module 300 and is connected to at least two temperature sensor junction boxes 240 via a second temperature signal transmission line 250, for receiving temperature signals output by the connected temperature sensors 210. This embodiment achieves simultaneous monitoring of the temperature of multiple switches and over-temperature protection through a single control board.

[0049] In this embodiment, the voltage module 500 uses an external inverter. The over-temperature protection power supply box 320 is equipped with an inverter interface 350. The power input line 330 is connected to the inverter, and the inverter is connected to the comparator module 300 through the inverter interface 350.

[0050] Those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, such as ROM / RAM, disk, optical disk, etc.

[0051] The above-disclosed embodiments are merely preferred embodiments of the present utility model and should not be construed as limiting the scope of the present utility model. Therefore, any equivalent variations made in accordance with the claims of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A photovoltaic DC switch with over-temperature protection function, comprising a photovoltaic DC switch body (100), wherein the photovoltaic DC switch body (100) has an open state and a closed state; characterized in that: It also includes, A temperature sensor detection module (200) is installed on the photovoltaic DC switch body (100) to detect the temperature of the photovoltaic DC switch body (100) and output a temperature signal; The comparison module (300) is connected to the temperature sensor detection module (200) and is used to receive the temperature signal and compare the temperature signal with the preset temperature threshold signal. When it is determined that the temperature corresponding to the signal transmitted by the temperature sensor exceeds the temperature threshold, an execution signal is output. The protection action execution module (400) is installed on the photovoltaic DC switch body (100) and connected to the comparison module (300). When the protection action execution module (400) receives the execution signal, the protection action execution module (400) outputs the protection action, driving the photovoltaic DC switch body (100) in the closed state to switch to the open state.

2. The photovoltaic DC switch with over-temperature protection function according to claim 1, characterized in that: The temperature sensor detection module (200) has a temperature sensing point set on the outer surface of the photovoltaic DC switch body (100) near the terminal block.

3. The photovoltaic DC switch with over-temperature protection function according to claim 1, characterized in that: A photovoltaic DC switch body (100) includes several switching units that operate synchronously. The temperature sensor detection module (200) provides temperature sensing points on the outer surface of some or all of the switching units of each photovoltaic DC switch body (100).

4. The photovoltaic DC switch with over-temperature protection function according to claim 1, characterized in that: The photovoltaic DC switch body (100) has an energy storage mechanism. The energy storage mechanism has an energy storage state and an energy release state. When the energy storage device is in the energy storage state, the photovoltaic DC switch body (100) can normally switch between the open state and the closed state. When the energy storage device switches from the energy storage state to the energy release state, it drives the photovoltaic DC switch body (100) in the closed state to switch to the open state. The protection action execution module (400) works in conjunction with the energy storage mechanism. When the protection action execution module (400) receives an execution signal, it drives the energy storage mechanism to switch from the energy storage state to the energy release state.

5. The photovoltaic DC switch with over-temperature protection function according to claim 4, characterized in that: The protection action execution module (400) is an electromagnetic drive device, and the execution signal is an electrical signal that powers on the electromagnetic drive device.

6. The photovoltaic DC switch with over-temperature protection function according to claim 5, characterized in that: A voltage module (500) is provided, which is used to output the high voltage DC power of the photovoltaic power source as a low voltage DC output.

7. The photovoltaic DC switch with over-temperature protection function according to claim 1, characterized in that: It also includes an over-temperature protection box (310) for housing the comparison module (300); The temperature sensor detection module (200) includes a temperature sensor (210) and a temperature signal transmission line. The temperature sensor (210) is connected to the over-temperature protection box (310) through the temperature signal transmission line.

8. The photovoltaic DC switch with over-temperature protection function according to claim 7, characterized in that: The over-temperature protection box (310) is detachably connected to the outer wall of the photovoltaic DC switch body (100). The temperature sensor detection module (200) has a temperature sensing point on the outer wall of the photovoltaic DC switch body (100) near the over-temperature protection box (310). The temperature signal transmission line is connected to the outer wall of the over-temperature protection box (310) near the photovoltaic DC switch body (100), and the over-temperature protection box (310) near the outer wall of the photovoltaic DC switch body (100) has a take-up groove (311) for accommodating the temperature signal transmission line.

9. The photovoltaic DC switch with over-temperature protection function according to claim 1, characterized in that: The temperature sensor detection module (200) includes at least two temperature sensor junction boxes (240); A temperature sensor junction box (240) is set for a photovoltaic DC switch body (100). Each temperature sensor junction box (240) is connected to several temperature sensors (210) through a first temperature signal transmission line. The several temperature sensors (210) are respectively set at different positions of the corresponding photovoltaic DC switch body (100). It also includes an over-temperature protection power supply box (320), which houses the comparison module (300) and is connected to at least two temperature sensor boxes (240) via a second temperature signal transmission line (250) for receiving temperature signals output by the connected temperature sensors (210).

10. A photovoltaic system comprising a photovoltaic DC switch with over-temperature protection as described in any one of claims 1-9, characterized in that, include: Photovoltaic power panel (600) is used to output high-voltage DC power; The photovoltaic DC switch body (100) is connected to a device for controlling the on / off state of the high-voltage DC power output from the photovoltaic power panel (600); The comparison module (300) is connected to the high-voltage DC power output from the photovoltaic power panel (600).

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