CN215222137U - Photovoltaic system - Google Patents
Photovoltaic system Download PDFInfo
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- CN215222137U CN215222137U CN202121300371.3U CN202121300371U CN215222137U CN 215222137 U CN215222137 U CN 215222137U CN 202121300371 U CN202121300371 U CN 202121300371U CN 215222137 U CN215222137 U CN 215222137U
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- photovoltaic
- photovoltaic system
- sensing device
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- photovoltaic module
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- 238000012544 monitoring process Methods 0.000 claims abstract description 22
- 230000001105 regulatory effect Effects 0.000 claims description 8
- 239000000779 smoke Substances 0.000 claims description 3
- 230000001276 controlling effect Effects 0.000 claims 1
- 238000004891 communication Methods 0.000 abstract description 8
- 206010014357 Electric shock Diseases 0.000 abstract description 5
- 230000009977 dual effect Effects 0.000 abstract 1
- 230000002159 abnormal effect Effects 0.000 description 15
- 238000000034 method Methods 0.000 description 10
- 230000005856 abnormality Effects 0.000 description 3
- 238000010030 laminating Methods 0.000 description 3
- 230000005611 electricity Effects 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 1
- 238000005286 illumination Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
Abstract
The utility model provides a photovoltaic system, include: the photovoltaic system also comprises a sensing device used for monitoring the operation environment of the photovoltaic system, and the sensing device is in communication connection with the main controller so that the main controller controls the operation state of the photovoltaic system according to the monitoring result of the sensing device. Compared with the prior art, the utility model discloses not only can utilize sensing device automatic monitoring photovoltaic system's operational environment, can send turn-off signal or stop sending the permission running signal by main control unit when sensing device monitors unusually moreover, avoid non-professional maloperation to arouse the electric shock risk, also can realize the dual fail-safe of manual operation and automatic operation under emergency simultaneously.
Description
Technical Field
The utility model relates to a solar energy component field especially relates to a photovoltaic system.
Background
With the gradual popularization of distributed photovoltaic power stations, the distributed photovoltaic power stations become important components of photovoltaic systems in the future, and photovoltaic modules are widely installed on roofs of civil houses, industrial plants, markets and the like.
The photovoltaic module can produce very high fatal voltage under the illumination condition, and this will bring serious threat to the installation of photovoltaic power plant, maintenance and the work of putting out a fire. How to ensure that emergency personnel are not shocked by the high voltage of the component array in the field treatment becomes a problem to be solved urgently.
At present, most power stations can only realize the function of switching off a main inverter end, which can only cut off the current in the power station, but the power station still has high voltage, and the voltage of a general distributed array is more than 400V, so that the danger that emergency personnel are shocked by high voltage can be caused. The us NEC 2017-Article 690.12 requires that photovoltaic circuits on or in buildings need to be equipped with a fast shut-off function to reduce the shock hazard for emergency response personnel. At present, the mainstream of developed countries such as europe and america is to configure a micro inverter to control the electrical output of each component, but the cost of the scheme is higher and is against the large background of the price-balancing internet access.
In view of the above, it is necessary to provide a photovoltaic system to solve the above problems.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to provide a low-cost, safe photovoltaic system. The photovoltaic system can cut off a circuit in the photovoltaic system at any time, so that the maximum output voltage of the photovoltaic system is reduced to the human body safety voltage, and constructors are prevented from being shocked by high voltage electricity.
In order to achieve the above object, the utility model provides a photovoltaic system, include: the photovoltaic system comprises a photovoltaic module, a local manager, a main controller and an inverter, wherein the inverter is electrically connected with the photovoltaic module through a main line, one end of the local manager is connected with the photovoltaic module, and the other end of the local manager is connected to the main line.
As a further improvement, the sensing device is an early warning sensor.
As a further improvement of the utility model, the sensing device is any one or combination of a plurality of temperature sensor, smoke transducer, fire sensor, voltage sensor and current sensor.
As a further improvement, the main control unit is capable of manually inquiring the main control unit of the monitoring result of the sensing device.
As a further improvement of the present invention, the main controller is a main controller capable of receiving the signal transmitted by the sensing device.
As a further improvement of the present invention, the local manager includes a signal receiving terminal connected to the main controller and a switch or a voltage regulator connected to the photovoltaic module, the signal receiving terminal is used for receiving the signal sent by the main controller, and according to the signal control, the switch or the voltage regulator with the connection or the disconnection of the photovoltaic module.
As a further improvement of the present invention, the switch is connected in series with the photovoltaic module, and when the switch is closed, the photovoltaic module is normally connected to the main line; when the switch is open, the photovoltaic module is disconnected from the main line.
As a further improvement of the present invention, the switch is connected in parallel with the photovoltaic module, and when the switch is turned off, the photovoltaic module is connected to the main line at a low voltage; when the switch is opened, the photovoltaic module is normally connected with the main line.
As a further improvement of the present invention, the voltage regulating device is a DC/DC power converter.
As a further improvement, the main control unit is capable of being manually operated to control the main control unit of the running state of the photovoltaic system.
The utility model has the advantages that: the utility model discloses a photovoltaic system is connected through setting sensing device and main control unit to the communication to not only can utilize sensing device automatic monitoring photovoltaic system's operational environment, can send turn-off signal or stop sending the permission running signal by main control unit when sensing device monitors unusually moreover, avoid the electric shock risk that non-professional's maloperation arouses, in addition, also can realize the double insurance of manual operation and automatic operation under emergency.
Drawings
Fig. 1 is a schematic structural diagram of the photovoltaic system of the present invention.
Fig. 2 is a flow chart of a method for normal operation of the photovoltaic system of the present invention.
Fig. 3 is a flow chart of a method for abnormal operation of the photovoltaic system of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in detail with reference to the accompanying drawings and specific embodiments.
In order to avoid obscuring the present invention with unnecessary details, it should be noted that only the structures and/or processing steps closely related to the aspects of the present invention are shown in the drawings, and other details not relevant to the present invention are omitted.
In addition, it is also to be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, 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 process, method, article, or apparatus.
In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in detail with reference to the accompanying drawings and specific embodiments.
As shown in fig. 1, the utility model discloses a photovoltaic system, include: the photovoltaic system comprises a photovoltaic module, a local manager, a main controller and an inverter, wherein the inverter is electrically connected with the photovoltaic module through a main line, one end of the local manager is connected with the photovoltaic module, the other end of the local manager is connected to the main line, the local manager is in communication connection with the main controller to control the connection of the photovoltaic module and the main line, the photovoltaic system further comprises a sensing device used for monitoring the operation environment of the photovoltaic system, and the sensing device is in communication connection with the main controller so that the main controller can control the operation state of the photovoltaic system according to the monitoring result of the sensing device. The setting of sensing device not only can automatic monitoring photovoltaic system's operational environment, can directly send turn-off signal or directly stop sending when unusual and allow the operation signal moreover, avoid the electric shock risk that non-professional's maloperation arouses.
In a preferred embodiment of the present application, there are a plurality of photovoltaic modules, and a plurality of local managers are correspondingly provided, so that each photovoltaic module can be connected to and disconnected from the main line through the corresponding local manager. The main controller is provided with one and is arranged in the inverter to be used as a component or a function of the inverter, and each local manager is in communication connection with the main controller through a wireless network or a PLC (programmable logic controller) so as to receive signals sent by the main controller. The sensing device is arranged in the main controller and is in communication connection with the main controller through a wireless network or a PLC (programmable logic controller), so that the main controller controls the running state of the photovoltaic system according to the monitoring result of the sensing device. Of course, in other embodiments, the number of local managers may also be set to be less than the number of photovoltaic modules, and one local manager may be used to control the on/off of a plurality of photovoltaic modules, which is not limited herein. The main controller may also be separately disposed at any position of the photovoltaic system, and is not limited herein. The sensing device may also be disposed in the local manager, or at any position in the photovoltaic system, as long as it can be communicatively connected with the main controller, which is not limited herein.
The photovoltaic module comprises a photovoltaic laminating part and a frame positioned on the periphery of the photovoltaic laminating part, and the local manager is arranged on the photovoltaic module and is specifically positioned on the frame or the photovoltaic laminating part. Preferably, the local manager may be mechanically attached to the frame of the photovoltaic module, or may be adhered to the back sheet of the photovoltaic laminate, which is not particularly limited herein.
Preferably, the sensing device is a pre-warning sensor. When the sensing device monitors that the environmental condition of the operation of the photovoltaic system is abnormal, an early warning signal is sent to the main controller, and the main controller controls the operation state of the photovoltaic system according to the monitoring result of the sensing device.
Further, the main controller controls the operation state of the photovoltaic system by inquiring the monitoring result of the sensing device or receiving the signal sent by the sensing device. Specifically, when the sensor device monitors that the environmental condition of the photovoltaic system is abnormal, the main controller can query the monitoring result or receive the early warning signal sent by the sensor device, and then send a turn-off signal or stop sending an operation permission signal to the local manager, so that the local manager controls the connection and disconnection of the photovoltaic module and the main line to control the operation state of the photovoltaic system.
Referring to fig. 2, the method for normal operation of the photovoltaic system of the present invention mainly includes the following steps: the method comprises the following steps that a main controller sends out an operation permission signal, a local manager receives the operation permission signal sent by the main controller and then starts up in a set time period, and a photovoltaic module can output normal voltage to an inverter; during non-set time periods (i.e., all time periods except the "set time period"), the local manager is turned off, so that the photovoltaic module is disconnected from the main line or the photovoltaic module is connected to the main line at a low voltage.
The above-mentioned "setting time period" may be set to: the local manager receives any one operation permission signal sent by the main controller from T1 to T2; the "unset period" is set to: not between any of the time points T1 to T2, where T2 is later than T1, at which the run enable signal is enabled.
Of course, the number of the operation permission signals is not limited to one, and may be plural. When the number of the operation permission signals is multiple, the local manager is started between time points T1 to T2 after receiving each operation permission signal sent by the main controller, so that the photovoltaic module outputs normal voltage to the inverter; and the local manager disconnects the photovoltaic module from the main line or reduces the output voltage of the photovoltaic module when the photovoltaic module is not in any time point between T1 and T2 of the allowed operation signal.
Through this setting, make the utility model discloses a photovoltaic system need not judge whether some pulses have been skipped to the permission running signal when normal operating, but directly switches on or shuts off photovoltaic module according to the rule (if set for the time quantum) that has or not and preset of permission running signal, has reduced the judgement process, has strengthened reliability and security.
Referring to fig. 3, the operation method of the photovoltaic system according to the present invention when monitoring an abnormality mainly includes the following steps: the photovoltaic module is electrically connected with the main circuit; monitoring the operating environment of the photovoltaic system by a sensing device; and the main controller controls the running state of the photovoltaic system according to the monitoring result of the sensing device.
Further, the operating state of the photovoltaic system in this application includes: the photovoltaic module is normally connected with the main line, disconnected with the main line and connected with the main line at low voltage. When the main controller sends out an operation permission signal, the local manager receives the operation permission signal sent out by the main controller in a set time period, the local manager is started, the photovoltaic module is connected to the main line, and at the moment, the operation state of the photovoltaic system is that the photovoltaic module is normally connected with the main line. When the sensing device monitors that the operating environment of the photovoltaic system is abnormal, the sensing device sends an abnormal signal to the main controller, or the main controller inquires the abnormal monitoring result, the main controller sends a turn-off signal or stops sending an operation allowing signal, so that the local manager is disconnected, the photovoltaic module is disconnected from the main line or the output voltage of the photovoltaic module is reduced, and at the moment, the operating state of the photovoltaic system is that the photovoltaic module is disconnected from the main line or the photovoltaic module is connected with the main line at a low voltage. Set sensing device and main control unit to the communication and be connected, not only can automatic monitoring photovoltaic system's operational environment, can directly send shut off signal or directly stop sending the permission running signal by main control unit when appearing unusually moreover, avoid the electric shock risk that non-professional's maloperation arouses.
Further, when the sensing device detects that the abnormal state has disappeared, the sensing device may send a monitoring result to the main controller, or after the main controller inquires that the abnormal state has disappeared, the main controller may continue to send an operation permission signal, and the local manager receives the operation permission signal sent by the main controller within a set time period (for example, between T1 and T2 time points after each operation permission signal sent by the main controller), and controls the photovoltaic module to be normally connected to the main line.
In this application, the monitoring of the operating environment abnormality of the photovoltaic system by the sensing device means: and when the value monitored by the sensing device continuously or repeatedly exceeds a preset value in preset time, judging that the operating environment of the photovoltaic system monitored by the sensing device is abnormal. The "predetermined time" and the "preset value" are not limited to specific values, and can be set according to specific actual conditions.
When the sensing device monitors that the operating environment of the photovoltaic system is abnormal, the main controller sends a turn-off signal or stops sending an operation permission signal to the local manager, and the local manager controls the photovoltaic module to be disconnected with the main line or the photovoltaic module to be connected with the main line at low voltage.
In particular, the sensing device may be a temperature sensor, a smoke sensor, a fire sensor, a voltage sensor, a current sensor or other warning sensor, which is not limited herein. The following will exemplify a temperature sensor.
When the temperature sensor monitors that the temperature around the operating environment of the photovoltaic system continuously or repeatedly exceeds a preset value (such as 200 ℃) within a preset time, the temperature sensor can judge that the temperature is abnormal. The "predetermined time" and the "preset value" are not limited to specific values, and can be set according to specific actual conditions.
When the temperature sensor tests that the temperature is abnormal, the temperature sensor can send a temperature abnormal signal to the main controller, the main controller sends a turn-off signal or stops sending an operation permission signal to the local manager, and the local manager controls the photovoltaic module to be disconnected with the main line or the photovoltaic module to be connected with the main line at low voltage. Of course, the main controller can also automatically query the monitoring result of the temperature sensor to judge whether the temperature sensor monitors the abnormality or not, and then judge whether the running state of the photovoltaic system needs to be changed automatically or not, so that the photovoltaic module is disconnected from the main line or is connected with the main line at low voltage.
As one of the preferred embodiments of the utility model discloses a local manager includes the signal reception end of being connected with main control unit and the switch of being connected with signal reception end, and signal reception end is used for receiving the permission running signal or the turn-off signal that main control unit sent to control switch is closed or is opened. When the signal receiving end receives the operation permission signal within a set time period (between the time points of T1 and T2), the control switch is closed or opened, so that the photovoltaic module is connected to the main line and outputs normal voltage to the inverter. When the signal receiving end receives the operation permission signal in the non-set time period (namely, between the non-T1 time point and the T2 time point), or the signal receiving end receives the turn-off signal or does not receive the operation permission signal, the control switch is opened or closed, so that the photovoltaic module is disconnected from the main line or is connected with the main line at low voltage.
Specifically, the switch and the photovoltaic module can be connected in series or in parallel. When the switch is connected with the photovoltaic module in series, if the signal receiving end receives an operation permission signal sent by the main controller within a set time period (between time points T1 and T2), the switch is controlled to be closed, and at the moment, the photovoltaic module is normally connected with the main line and outputs normal voltage to the inverter. If the signal receiving end receives the operation permission signal in the non-set time period (namely, between the non-T1 time point and the T2 time point), or the signal receiving end receives the turn-off signal or does not receive the operation permission signal, the control switch is turned on, and at the moment, the photovoltaic module is disconnected with the main line. When the switch is connected with the photovoltaic module in parallel, if the signal receiving end receives an operation permission signal sent by the main controller within a set time period (between time points T1 and T2), the switch is controlled to be opened, and at the moment, the photovoltaic module is normally connected with the main line and can output normal voltage to the inverter. When the signal receiving end receives the operation permission signal in the non-set time period (namely, between the non-T1 time point and the T2 time point), or the signal receiving end receives the turn-off signal or does not receive the operation permission signal, the control switch is closed, and at the moment, the photovoltaic module is connected with the main line at low voltage and outputs the low voltage to the inverter. Of course, the "low voltage" herein refers to a human body safety voltage, and the specific value is not limited as long as it can ensure that emergency response personnel are not shocked by a high voltage when handling emergency abnormal events.
As another preferred embodiment of the present invention, the switch in the above embodiment may be replaced with a voltage regulator. When the signal receiving end receives an operation permission signal sent by the main controller within a set time period (between the time points of T1 and T2), the voltage regulating device is controlled to operate, the photovoltaic module is normally connected with the main line, and normal voltage is output to the inverter. When the signal receiving end receives the operation permission signal in the non-set time period (namely, between the non-T1 time point and the T2 time point), or the signal receiving end receives the turn-off signal or cannot receive the operation permission signal, the voltage regulating device is controlled to operate, the output voltage of the photovoltaic assembly is regulated, and the photovoltaic assembly is connected with the main line at low voltage so as to reduce the output voltage of the photovoltaic assembly. Preferably, the voltage regulating device is a DC/DC power converter.
With continued reference to fig. 3, the main controller may also stop sending the operation-allowing signal or sending the shutdown signal by human operation, such as: and manually switching off the main controller, so that the main controller stops sending an operation permission signal or sends a switching-off signal to the local manager, the local manager is switched off, and the photovoltaic module is disconnected from the main line or is connected with the main line at low voltage.
Or when the constructor handles an emergency abnormal event or the sensing device fails, the circuit in the photovoltaic system can be manually cut off or automatically cut off at any time, so that the maximum voltage output of the photovoltaic system is reduced to the human safety voltage, the constructor is ensured not to be shocked by high voltage electricity, and double insurance of manual operation and automatic operation is realized in an emergency.
To sum up, the utility model discloses a photovoltaic system is connected through setting sensing device and main management ware to the communication to not only can automatic monitoring photovoltaic system's operational environment, can directly send turn-off signal or directly stop sending by main control unit and allow the operating signal when appearing unusually moreover, avoid the electric shock risk that non-professional's maloperation arouses, in addition, also can realize the double insurance of manual operation and automatic operation under emergency.
The above embodiments are only for illustrating the technical solutions of the present invention and not for limiting, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present invention can be modified or replaced equivalently without departing from the spirit and scope of the technical solutions of the present invention.
Claims (10)
1. A photovoltaic system, comprising: the photovoltaic system comprises a photovoltaic module, a local manager, a main controller and an inverter, wherein the inverter is electrically connected with the photovoltaic module through a main line, one end of the local manager is connected with the photovoltaic module, and the other end of the local manager is connected to the main line.
2. The photovoltaic system of claim 1, wherein: the sensing device is an early warning sensor.
3. The photovoltaic system of claim 1, wherein: the sensing device is any one or more of a temperature sensor, a smoke sensor, a fire sensor, a voltage sensor and a current sensor.
4. The photovoltaic system of claim 1, wherein: the main controller is capable of manually inquiring the monitoring result of the sensing device.
5. The photovoltaic system of claim 1, wherein: the main controller is capable of receiving the signals sent by the sensing device.
6. The photovoltaic system of claim 1, wherein: the local manager comprises a signal receiving end connected with the main controller and a switch or a voltage regulating device connected with the photovoltaic assembly, wherein the signal receiving end is used for receiving a signal sent by the main controller and controlling the connection or disconnection between the switch or the voltage regulating device and the photovoltaic assembly according to the signal.
7. The photovoltaic system of claim 6, wherein: the switch is connected with the photovoltaic module in series, and when the switch is closed, the photovoltaic module is normally connected with the main line; when the switch is open, the photovoltaic module is disconnected from the main line.
8. The photovoltaic system of claim 6, wherein: the switch is connected with the photovoltaic module in parallel, and when the switch is closed, the photovoltaic module is connected with the main line at low voltage; when the switch is opened, the photovoltaic module is normally connected with the main line.
9. The photovoltaic system of claim 6, wherein: the voltage regulating device is a DC/DC power converter.
10. The photovoltaic system of claim 1, wherein: the main controller is capable of being manually operated to control the running state of the photovoltaic system.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121300371.3U CN215222137U (en) | 2021-06-10 | 2021-06-10 | Photovoltaic system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121300371.3U CN215222137U (en) | 2021-06-10 | 2021-06-10 | Photovoltaic system |
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| Publication Number | Publication Date |
|---|---|
| CN215222137U true CN215222137U (en) | 2021-12-17 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202121300371.3U Active CN215222137U (en) | 2021-06-10 | 2021-06-10 | Photovoltaic system |
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| CN (1) | CN215222137U (en) |
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2021
- 2021-06-10 CN CN202121300371.3U patent/CN215222137U/en active Active
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