阅读说明：本技术 一种具有安全保护功能的光伏系统 (Photovoltaic system with safety protection function ) 是由 罗宇浩 周懂明 于 2018-08-03 设计创作，主要内容包括：本发明公开了一种具有安全保护功能的光伏系统,包括：多个光伏组件、多个电缆关断器、关断控制器和逆变器；其中,多个所述光伏组件通过电缆串联连接,串联连接完成后接入所述逆变器；相邻两个所述光伏组件之间的电缆上设置有一个所述电缆关断器；所述关断控制器用于控制所述电缆关断器的工作状态,以使相邻两个所述光伏组件之间的电缆处于导通状态或截止状态。该光伏系统通过在相邻两个光伏组件之间的电缆上增设电缆关断器,从根本上解决了逆变器停止运行之后,光伏组件串起来以后的直流电缆还是会输出高电压的问题,极大程度的提高了光伏系统的安全性。(The invention discloses a photovoltaic system with a safety protection function, which comprises: the photovoltaic power generation system comprises a plurality of photovoltaic assemblies, a plurality of cable breakers, a shutdown controller and an inverter; the photovoltaic modules are connected in series through cables, and the photovoltaic modules are connected into the inverter after the series connection is finished; a cable shutoff device is arranged on a cable between two adjacent photovoltaic modules; the turn-off controller is used for controlling the working state of the cable turn-off device so as to enable a cable between every two adjacent photovoltaic modules to be in a conducting state or a cut-off state. According to the photovoltaic system, the cable breaker is additionally arranged on the cable between every two adjacent photovoltaic modules, so that the problem that a direct current cable after the photovoltaic modules are connected in series still outputs high voltage after the inverter stops running is fundamentally solved, and the safety of the photovoltaic system is greatly improved.)

1. A photovoltaic system with safety protection, the photovoltaic system comprising: the photovoltaic power generation system comprises a plurality of photovoltaic assemblies, a plurality of cable breakers, a shutdown controller and an inverter;

the photovoltaic modules are connected in series through cables, and the photovoltaic modules are connected into the inverter after the series connection is finished;

a cable shutoff device is arranged on a cable between two adjacent photovoltaic modules;

the turn-off controller is used for controlling the working state of the cable turn-off device so as to enable a cable between every two adjacent photovoltaic modules to be in a conducting state or a cut-off state.

2. The photovoltaic system of claim 1, wherein a plurality of the cable breakers are connected in series;

and after the serial connection is finished, the output end of the turn-off controller is accessed.

3. The photovoltaic system of claim 2, wherein the cable breaker comprises a switch control module and a relay switch;

the input end of the relay switch is connected with one of the two adjacent photovoltaic assemblies through a cable, and the output end of the relay switch is connected with the other of the two adjacent photovoltaic assemblies through a cable;

the switch control module is connected with the control end of the relay switch;

the switch control modules in the cable breakers are connected in series, and the switch control modules are connected to the output end of the switch controller after being connected in series;

the turn-off controller is used for controlling the working state of the relay switch through the switch control module.

4. The photovoltaic system of claim 3, wherein the shutdown controller is connected to an AC power grid;

the turn-off controller is also used for converting alternating current in the alternating current power grid into a direct current voltage signal;

the turn-off controller is further used for providing the direct-current voltage signal to the switch control module;

and the switch control module controls the working state of the relay switch according to the direct-current voltage signal.

5. The photovoltaic system of claim 3, wherein the shutdown controller is connected to an AC power grid;

the turn-off controller is also used for converting alternating current in the alternating current power grid into a direct current signal;

the turn-off controller is further used for providing the direct current signal to the switch control module;

and the switch control module controls the working state of the relay switch according to the direct current signal.

6. The photovoltaic system of claim 1, wherein a plurality of the cable breakers are connected in parallel;

and after the parallel connection is finished, the output end of the turn-off controller is accessed.

7. The photovoltaic system of claim 6, wherein the cable breaker comprises a switch control module and a relay switch;

the input end of the relay switch is connected with one of the two adjacent photovoltaic assemblies through a cable, and the output end of the relay switch is connected with the other of the two adjacent photovoltaic assemblies through a cable;

the switch control module is connected with the control end of the relay switch;

the switch control modules in the cable breakers are connected in parallel, and the switch control modules are connected to the output end of the switch-off controller after the parallel connection is finished;

the turn-off controller is used for controlling the working state of the relay switch through the switch control module.

8. The photovoltaic system of claim 7, wherein the shutdown controller is connected to an AC power grid;

the turn-off controller is also used for converting alternating current in the alternating current power grid into a direct current voltage signal;

the turn-off controller is further used for providing the direct-current voltage signal to the switch control module;

and the switch control module controls the working state of the relay switch according to the direct-current voltage signal.

9. The photovoltaic system of claim 6, wherein the cable breaker comprises a switch control module, a relay switch, and an AC/DC power module;

the input end of the relay switch is connected with one of the two adjacent photovoltaic assemblies through a cable, and the output end of the relay switch is connected with the other of the two adjacent photovoltaic assemblies through a cable;

the switch control module is respectively connected with the control end of the relay switch and the AC/DC power supply module;

the AC/DC power supply modules in the cable breakers are connected in parallel, and the AC/DC power supply modules are connected to the output end of the shutdown controller after the parallel connection is finished;

and the AC/DC power supply module is used for supplying power to the switch control module according to the voltage signal sent by the turn-off controller so as to control the working state of the relay switch.

10. The photovoltaic system of claim 9, wherein the shutdown controller is connected to an ac power grid;

the shutdown controller is further configured to transmit the alternating current in the alternating current grid to the AC/DC power module.

Technical Field

The invention relates to the technical field of photovoltaic power generation, in particular to a photovoltaic system with a safety protection function.

Background

With the continuous development of science and technology, solar energy is used as renewable energy and has the advantage of cleanness, and the photovoltaic grid-connected power generation technology is rapidly developed.

Based on the current photovoltaic system, as shown in fig. 1, a plurality of photovoltaic modules are connected in series to form a string, and then an inverter is connected to convert direct current into alternating current for grid connection. However, the high dc voltage formed by the series-connected photovoltaic modules can cause personal hazards and fire accidents. Therefore, inverters currently have arc protection measures, i.e. the operation of the inverter is immediately switched off when an arc is detected. However, even if the inverter stops operating, the dc cable after the photovoltaic modules are strung up still outputs high voltage, and there is still a safety risk.

Disclosure of Invention

In order to solve the problems, the invention provides a photovoltaic system with a safety protection function, which further effectively improves the safety of the photovoltaic system and solves the problems in the prior art.

In order to achieve the purpose, the invention provides the following technical scheme:

a photovoltaic system having safety protection, the photovoltaic system comprising: the photovoltaic power generation system comprises a plurality of photovoltaic assemblies, a plurality of cable breakers, a shutdown controller and an inverter;

the photovoltaic modules are connected in series through cables, and the photovoltaic modules are connected into the inverter after the series connection is finished;

a cable shutoff device is arranged on a cable between two adjacent photovoltaic modules;

the turn-off controller is used for controlling the working state of the cable turn-off device so as to enable a cable between every two adjacent photovoltaic modules to be in a conducting state or a cut-off state.

Preferably, in the photovoltaic system, a plurality of the cable breakers are connected in series;

and after the serial connection is finished, the output end of the turn-off controller is accessed.

Preferably, in the photovoltaic system, the cable breaker includes a switch control module and a relay switch;

the input end of the relay switch is connected with one of the two adjacent photovoltaic assemblies through a cable, and the output end of the relay switch is connected with the other of the two adjacent photovoltaic assemblies through a cable;

the switch control module is connected with the control end of the relay switch;

the switch control modules in the cable breakers are connected in series, and the switch control modules are connected to the output end of the switch controller after being connected in series;

the turn-off controller is used for controlling the working state of the relay switch through the switch control module.

Preferably, in the photovoltaic system, the shutdown controller is connected to an ac power grid;

the turn-off controller is also used for converting alternating current in the alternating current power grid into a direct current voltage signal;

the turn-off controller is further used for providing the direct-current voltage signal to the switch control module;

and the switch control module controls the working state of the relay switch according to the direct-current voltage signal.

Preferably, in the photovoltaic system, the shutdown controller is connected to an ac power grid;

the turn-off controller is also used for converting alternating current in the alternating current power grid into a direct current signal;

the turn-off controller is further used for providing the direct current signal to the switch control module;

and the switch control module controls the working state of the relay switch according to the direct current signal.

Preferably, in the photovoltaic system, a plurality of the cable breakers are connected in parallel;

and after the parallel connection is finished, the output end of the turn-off controller is accessed.

Preferably, in the photovoltaic system, the cable breaker includes a switch control module and a relay switch;

the input end of the relay switch is connected with one of the two adjacent photovoltaic assemblies through a cable, and the output end of the relay switch is connected with the other of the two adjacent photovoltaic assemblies through a cable;

the switch control module is connected with the control end of the relay switch;

the switch control modules in the cable breakers are connected in parallel, and the switch control modules are connected to the output end of the switch-off controller after the parallel connection is finished;

the turn-off controller is used for controlling the working state of the relay switch through the switch control module.

Preferably, in the photovoltaic system, the shutdown controller is connected to an ac power grid;

the turn-off controller is also used for converting alternating current in the alternating current power grid into a direct current voltage signal;

the turn-off controller is further used for providing the direct-current voltage signal to the switch control module;

and the switch control module controls the working state of the relay switch according to the direct-current voltage signal.

Preferably, in the photovoltaic system, the cable breaker includes a switch control module, a relay switch and an AC/DC power supply module;

the input end of the relay switch is connected with one of the two adjacent photovoltaic assemblies through a cable, and the output end of the relay switch is connected with the other of the two adjacent photovoltaic assemblies through a cable;

the switch control module is respectively connected with the control end of the relay switch and the AC/DC power supply module;

the AC/DC power supply modules in the cable breakers are connected in parallel, and the AC/DC power supply modules are connected to the output end of the shutdown controller after the parallel connection is finished;

and the AC/DC power supply module is used for supplying power to the switch control module according to the voltage signal sent by the turn-off controller so as to control the working state of the relay switch.

Preferably, in the photovoltaic system, the shutdown controller is connected to an ac power grid;

the shutdown controller is further configured to transmit the alternating current in the alternating current grid to the AC/DC power module.

As can be seen from the above description, the present invention provides a photovoltaic system with safety protection function, including: the photovoltaic power generation system comprises a plurality of photovoltaic assemblies, a plurality of cable breakers, a shutdown controller and an inverter; the photovoltaic modules are connected in series through cables, and the photovoltaic modules are connected into the inverter after the series connection is finished; a cable shutoff device is arranged on a cable between two adjacent photovoltaic modules; the turn-off controller is used for controlling the working state of the cable turn-off device so as to enable a cable between every two adjacent photovoltaic modules to be in a conducting state or a cut-off state.

According to the photovoltaic system, the cable breaker is additionally arranged on the cable between every two adjacent photovoltaic modules, so that the problem that a direct current cable after the photovoltaic modules are connected in series still outputs high voltage after the inverter stops running is fundamentally solved, and the safety of the photovoltaic system is greatly improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

FIG. 1 is a schematic diagram of a connection structure of a photovoltaic system in the prior art;

fig. 2 is a schematic structural diagram of a photovoltaic system with a module shutdown device added in the prior art;

FIG. 3 is a schematic diagram of a prior art component shutoff;

fig. 4 is a schematic structural diagram of a photovoltaic system with a safety protection function according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of another photovoltaic system with a safety protection function according to an embodiment of the present invention;

fig. 6 is a schematic structural diagram of a cable breaker according to an embodiment of the present invention;

fig. 7 is a schematic diagram of a shutdown controller and an ac power grid according to an embodiment of the present invention;

fig. 8 is a schematic diagram of another shutdown controller and ac power grid according to an embodiment of the present invention;

fig. 9 is a schematic structural diagram of another photovoltaic system with a safety protection function according to an embodiment of the present invention;

fig. 10 is a schematic structural diagram of a cable breaker integrated in a junction box of a photovoltaic module according to an embodiment of the present invention;

fig. 11 is a schematic structural diagram of another photovoltaic system with a safety protection function according to an embodiment of the present invention;

fig. 12 is a schematic structural diagram of another cable shutter according to an embodiment of the present invention;

fig. 13 is a schematic diagram of a principle between a shutdown controller and an ac power grid according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.

Referring to fig. 4, fig. 4 is a schematic structural diagram of a photovoltaic system with a safety protection function according to an embodiment of the present invention, where the photovoltaic system includes: a plurality of photovoltaic modules 11, a plurality of cable breakers 12, a shutdown controller 13, and an inverter 14;

the photovoltaic modules 11 are connected in series through cables, and are connected to the inverter 14 after the series connection is completed;

a cable breaker 12 is arranged on a cable between two adjacent photovoltaic modules 11;

the shutdown controller 13 is configured to control an operating state of the cable shutdown device 12, so that a cable between two adjacent photovoltaic modules 11 is in a conducting state or a shutdown state.

Specifically, the cable breaker is additionally arranged on the cable between two adjacent photovoltaic modules of the photovoltaic system, so that the problem that the direct-current cable after the photovoltaic modules are connected in series still outputs high voltage after the inverter stops running is fundamentally solved, and the safety of the photovoltaic system is greatly improved.

Further, as shown in fig. 5, a plurality of the cable breakers 12 are connected in series.

The output of the shutdown controller 13 is switched on after the series connection is completed.

Further, as shown in fig. 6, the cable breaker 12 includes a switch control module 16 and a relay switch 15.

The input end of the relay switch 15 is connected with one of the two adjacent photovoltaic modules 11 through a cable, and the output end of the relay switch 15 is connected with the other of the two adjacent photovoltaic modules 11 through a cable.

The switch control module 16 is connected with the control end of the relay switch 15.

As shown in fig. 5, the switch control modules 16 in a plurality of cable interrupters 12 are connected in series, and the output terminal of the shutdown controller 13 is connected after the series connection is completed.

The turn-off controller 13 is configured to control the working state of the relay switch through the switch control module 16.

Specifically, the cable breaker 12 includes two power connectors IN and OUT corresponding to the input and output terminals of the relay switch 15, and two power connectors c + and c-.

For the power connector, the power connector IN is connected with one of the two adjacent photovoltaic modules 11 through a cable, and the power connector OUT is connected with the other of the two adjacent photovoltaic modules 11 through a cable.

For the power connector, when the serial connection between the switch control modules 16 in the plurality of cable interrupters 12 is completed, the power connector c + is connected to the positive terminal output terminal + of the shutdown controller 13, and the power connector c-is connected to the negative terminal output terminal-of the shutdown controller 13.

It should be noted that, since the arrangement of a plurality of connectors causes a problem of cost increase, even when it is clear how many cable breakers are required, the connectors may be directly connected in series through the connecting lines to form a whole series connection, and there is no need to add connectors and connect in series one by one.

Further, as shown in fig. 6, the shutdown controller 13 is connected to the ac power grid.

The shutdown controller 13 is also configured to convert the ac power in the ac power grid into a dc voltage signal.

The shutdown controller 13 is further configured to provide the dc voltage signal to the switch control module 16.

The switch control module 16 controls the working state of the relay switch 15 according to the direct-current voltage signal.

Alternatively, the shutdown controller 13 is connected to the ac power grid.

The shutdown controller 13 is also configured to convert the ac power in the ac power grid into a dc current signal.

The shutdown controller 13 is further configured to provide the dc current signal to the switch control module 16.

The switch control module 16 controls the working state of the relay switch 15 according to the direct current signal.

Specifically, as shown in fig. 7 and 8, the turn-off controller 13 further includes a first input end and a second input end, the first input end is connected to the live line L of the ac power grid, and the second input end is connected to the zero line N of the ac power grid.

As shown in fig. 7, when the shutdown controller 13 is used to output a dc voltage signal, the shutdown controller 13 converts the ac power in the ac power grid into dc voltage signals V + and V-. A plurality of the cable breakers 12 are each divided in voltage, the total voltage being equal to V +/V-.

As shown in fig. 8, when the shutdown controller 13 is configured to output a dc current signal, the shutdown controller 13 converts the ac power in the ac power grid into dc current signals I + and I-. Assuming that the impedance of each of the cable interrupters 12 is R, each of the cable interrupters 12 individually divides voltage by I × R.

Further, as shown in fig. 9, a plurality of the cable interrupters are connected in series.

And after the serial connection is finished, the output end of the turn-off controller is accessed.

And, the cable breaker is integrally disposed inside the junction box of the photovoltaic module 11.

Further, as shown in fig. 10, the photovoltaic module is exemplified by having 4 solder strips PV +, PV2, PV3, and PV-and 3 bypass diodes inside the junction box, and the cable breaker includes a switch control module 16 and a relay switch.

The input end of the relay switch is connected with the photovoltaic module, the output end of the relay switch is connected with the welding strip PV +, and then is connected with the next adjacent photovoltaic module.

When the switch control modules in the cable interrupters are connected in series, a power supply connector c + is connected with the output end of the positive end of the turn-off controller, and a power supply connector c-is connected with the output end of the negative end of the turn-off controller.

Further, as shown in fig. 11, a plurality of the cable breakers 12 are connected in parallel.

And after the parallel connection is finished, the output end of the turn-off controller 13 is connected.

Further, as shown in fig. 6, the cable breaker 12 includes a switch control module 16 and a relay switch 15.

Wherein, the input end of the relay switch 15 is connected with one of the two adjacent photovoltaic modules 11 through a cable, and the output end of the relay switch 15 is connected with the other of the two adjacent photovoltaic modules 11 through a cable.

The switch control module 16 is connected with the control end of the relay switch 15.

As shown in fig. 11, the switch control modules 16 in a plurality of cable interrupters 12 are connected in parallel, and after the parallel connection is completed, the output terminal of the shutdown controller 13 is connected.

The turn-off controller 13 is configured to control an operating state of the relay switch 15 through the switch control module 16.

Specifically, the cable breaker 12 includes two power connectors IN and OUT corresponding to the input and output terminals of the relay switch 15, and two power connectors c + and c-.

For the power connector, the power connector IN is connected with one of the two adjacent photovoltaic modules 11 through a cable, and the power connector OUT is connected with the other of the two adjacent photovoltaic modules 11 through a cable.

As for the power connectors, when the power connectors c + of the switch control modules 16 in the plurality of cable interrupters 12 are respectively connected to the positive side output terminals + of the shutdown controller 13, the power connectors c-are respectively connected to the negative side output terminals-of the shutdown controller 13 to form a parallel connection.

Further, as shown in fig. 11, the shutdown controller 13 is connected to the ac power grid.

The shutdown controller 13 is also configured to convert the ac power in the ac power grid into a dc voltage signal.

The shutdown controller 13 is further configured to provide the dc voltage signal to the switch control module 16.

The switch control module 16 controls the working state of the relay switch 15 according to the direct-current voltage signal.

Specifically, the turn-off controller 13 further includes a first input end and a second input end, the first input end is connected to the live line L of the ac power grid, and the second input end is connected to the zero line N of the ac power grid.

As shown in fig. 7, when the shutdown controller 13 is used to output a dc voltage signal, the shutdown controller 13 converts the ac power in the ac power grid into dc voltage signals V + and V-. The voltage across a plurality of the cable interrupters 12 is V.

Alternatively, as shown in fig. 12, the cable breaker 12 includes a switch control module 16, a relay switch 15, and an AC/DC power supply module 17.

Wherein, the input end of the relay switch 15 is connected with one of the two adjacent photovoltaic modules 11 through a cable, and the output end of the relay switch 15 is connected with the other of the two adjacent photovoltaic modules 11 through a cable.

The switch control module 16 is connected to the control terminal of the relay switch 15 and the AC/DC power module 17, respectively.

The AC/DC power modules 17 in the plurality of cable breakers 12 are connected in parallel, and are connected to the output terminal of the shutdown controller 13 after the parallel connection is completed.

The AC/DC power supply module 17 is configured to supply power to the switch control module 16 according to the voltage signal sent by the shutdown controller 13, so as to control the operating state of the relay switch 15.

As shown in fig. 13, the shutdown controller 13 is connected to an ac power grid.

The shutdown controller 13 is also configured to transmit the AC power in the AC power grid to the AC/DC power module 17.

That is to say, the switch-off controller 13 now acts as a switch control for the ac power in the ac power grid and does not convert the ac power.

The AC/DC power supply module 17 supplies power to the switch control module 16 directly according to the alternating current to control the working state of the relay switch 15.

According to the photovoltaic system, the cable breaker is additionally arranged on the cable between the two adjacent photovoltaic modules, so that the problem that the direct current cable after the photovoltaic modules are connected in series still outputs high voltage after the inverter stops running is fundamentally solved, and the safety of the photovoltaic system is greatly improved.

And, compared with the prior art, the structure of its cable breaker is based on the structure of subassembly breaker simpler, and the control mode is simpler, the cost is reduced.

It should be noted that, in the present specification, the embodiments are all described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments may be referred to each other.

It is further noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that an article or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such article or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in an article or device that comprises the element.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.