CN203911498U - Distributed photovoltaic grid-connected protective equipment - Google Patents
Distributed photovoltaic grid-connected protective equipment Download PDFInfo
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- CN203911498U CN203911498U CN201420199834.5U CN201420199834U CN203911498U CN 203911498 U CN203911498 U CN 203911498U CN 201420199834 U CN201420199834 U CN 201420199834U CN 203911498 U CN203911498 U CN 203911498U
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- input
- voltage
- distributed photovoltaic
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- power line
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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
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B10/00—Integration of renewable energy sources in buildings
- Y02B10/10—Photovoltaic [PV]
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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
- Y02E10/56—Power conversion systems, e.g. maximum power point trackers
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Abstract
The utility model discloses a set of distributed photovoltaic grid-connected protective equipment which is mounted on a power line for connecting a distributed photovoltaic power generating system and a power distribution network. The distributed photovoltaic grid-connected protective equipment is characterized in that: the distributed photovoltaic grid-connected protective equipment comprises a circuit breaker, an under-voltage time-delay protecting unit, an overvoltage protecting unit and a live switching-on unit; the circuit breaker is mounted on a power line; the input end of the under-voltage time-delay protecting unit is connected with the power line; the output end of the under-voltage time-delay protecting unit is connected with the circuit breaker for switching off the circuit breaker; the input end of the overvoltage protecting unit is connected with the power line; the output end of the overvoltage protecting unit is connected with the circuit breaker for switching off the circuit breaker; the input end of the live switching-on unit is connected with the power line; and the output end of the live switching-on unit is connected with the circuit breaker for switching on the circuit breaker. The distributed photovoltaic grid-connected protective equipment has functions of: realizing protection for distributed photovoltaic power generating connected grid points, unifying a distributed photovoltaic grid connecting manner, improving safety in household distributed photovoltaic power generating, and realizing monitoring and generating capacity counting for the photovoltaic power generating system.
Description
Technical field
The utility model relates to a kind of grid-connected protection equipment, is specifically related to the grid-connected protection equipment of a kind of distributed photovoltaic, and the utility model belongs to electrical protection apparatus field.
Background technology
Familial distribution of cases formula photovoltaic generating system is applicable to 30m
2～200m
2between house, photovoltaic capacity is installed at 1kW～10kW, with AC220V electric pressure access electrical network, institute's energy output consumes nearby, be generally generate power for their own use, remaining electric online pattern.
Country is just wideling popularize the application of distributed power generation at present, but the correlation technique specification of existing distributed power source access power distribution network is mainly for the photovoltaic generation project with 10KV above access electrical network, and also do not put into effect concrete technical specification for family's photovoltaic generating system, therefore access way is various at present, cause grid company to unify supervision to home-use house type distributed photovoltaic power station, along with family's photovoltaic generating system is more and more, add the intermittence that photovoltaic generation is brought by weather effect, bring very large impact to power distribution network.Because photovoltaic plant is directly installed on place of resident family, aspect user's personal safety, also there is certain hidden danger simultaneously.
At present, " the distributed power source access power distribution network correlation technique specification " put into effect according to Guo Wang company, not yet there is meeting the distributed photovoltaic relevant device of this specification in market now, and distributed photovoltaic is directly to access electrical network by circuit breaker to generate electricity by way of merging two or more grid systems mostly.Although reduced like this cost of distributed photovoltaic power generation, be not equipped with any protection equipment, bring potential safety hazard to the family that distributed photovoltaic power station is installed, distributed direct access has simultaneously brought very large impact also to the structure of power distribution network.
Utility model content
For solving the deficiencies in the prior art, the purpose of this utility model is to provide a kind of distributed photovoltaic grid-connected protection equipment, to solve the technical problem of the grid-connected shortage fail safe of distributed photovoltaic in prior art.
In order to realize above-mentioned target, the utility model adopts following technical scheme:
The grid-connected protection equipment of distributed photovoltaic, is arranged on the power line that connects distributed photovoltaic power generation system and power distribution network, it is characterized in that, comprising: circuit breaker, under-voltage delay protection unit, Overvoltage protecting unit, have pressing lock unit; Described circuit breaker is arranged on power line; The input of described under-voltage delay protection unit connects power line, and the output connecting breaker of under-voltage delay protection unit is so that breaker open operation; The input of described Overvoltage protecting unit connects power line, and the output connecting breaker of described Overvoltage protecting unit is so that breaker open operation; The described input that has pressing lock unit connects power line, has the output connecting breaker of pressing lock unit so that breaker closing.
The grid-connected protection equipment of aforesaid distributed photovoltaic; it is characterized in that; described under-voltage delay protection unit comprises under-voltage time delay module, device for under-voltage releasing equipment; the input of under-voltage time delay module connects power line; the output of under-voltage time delay module connects the input of device for under-voltage releasing equipment, the output connecting breaker of device for under-voltage releasing equipment.
The grid-connected protection equipment of aforesaid distributed photovoltaic; it is characterized in that; described Overvoltage protecting unit comprises the first motor-operating mechanism, the first input and output module, the first voltage monitor; the input of described the first voltage monitor connects power line; the output of the first voltage monitor connects the input of the first input and output module; the output of the first input and output module connects the first motor-operating mechanism after light-coupled isolation, and the first motor-operating mechanism connecting breaker is to drive breaker open operation.
The grid-connected protection equipment of aforesaid distributed photovoltaic; it is characterized in that; described have pressing lock unit to comprise the second motor-operating mechanism, the second input and output module, second voltage monitoring modular; the input of described second voltage monitoring modular connects power line; the output of described second voltage monitoring modular connects the input of the second input and output module; the output of described the second input and output module connects the second motor-operating mechanism after light-coupled isolation, and the second motor-operating mechanism connecting breaker is to drive breaker closing.
The grid-connected protection equipment of aforesaid distributed photovoltaic, is characterized in that, also comprise bidirectional measuring electric energy meter, described electric energy meter is arranged on power line.
The grid-connected protection equipment of aforesaid distributed photovoltaic, is characterized in that, also comprises lightning protection device, and the input of described lightning protection device connects power line, and the input of module is outputed in the output connection first of described lightning protection device.
The grid-connected protection equipment of aforesaid distributed photovoltaic, is characterized in that, described the first voltage monitoring module is connected respectively wireless signal sending module and man-machine interface with second voltage monitoring modular.
Usefulness of the present utility model is: the grid-connected protection equipment of distributed photovoltaic of the present utility model can make realization both unify distributed photovoltaic net mode to the protection of distributed photovoltaic power generation site; improve the fail safe of familial distribution of cases formula photovoltaic generation, can realize again monitoring and energy output statistics to photovoltaic generating system.
Brief description of the drawings
Fig. 1 is a structural representation of preferably implementing of the grid-connected protection equipment of the utility model distributed photovoltaic.
Fig. 2 is the further enforcement structure chart of the utility model based on Fig. 1;
Fig. 3 is the further enforcement structure chart of the utility model based on Fig. 2;
Fig. 4 is the further enforcement structure chart of the utility model based on Fig. 3;
The implication of Reference numeral in figure:
1, the grid-connected protection equipment of distributed photovoltaic, 2, power line.
Embodiment
Below in conjunction with the drawings and specific embodiments, the utility model is done to concrete introduction.
Shown in Fig. 1, the grid-connected protection equipment 1 of the utility model distributed photovoltaic, is arranged on the power line 2 that connects distributed photovoltaic power generation system and power distribution network, comprising: circuit breaker, under-voltage delay protection unit, Overvoltage protecting unit, have pressing lock unit; Circuit breaker is arranged on power line 2; The input of under-voltage delay protection unit connects power line, and the output connecting breaker of under-voltage delay protection unit is so that breaker open operation; The input of Overvoltage protecting unit connects power line, and the output connecting breaker of Overvoltage protecting unit is so that breaker open operation; There is the input of pressing lock unit to connect power line, have the output connecting breaker of pressing lock unit so that breaker closing.
In the utility model, distributed photovoltaic power generation system claims again distributing generating or distributed energy supply, refers to or close electricity consumption situ configuration less photovoltaic generation electric power system on-the-spot user.The capital equipment of distributed photovoltaic power generation system comprises the equipment such as photovoltaic cell component, photovoltaic arrays support, direct current conflux case, combining inverter.Circuit breaker is realized the isolation of distributed photovoltaic power generation system and electrical network, possesses short-circuit protection and overload protection function simultaneously.The schematic diagram of the grid-connected protection equipment of distributed photovoltaic is shown in Fig. 1 dotted line frame, and under-voltage delay protection unit is used for realizing under-voltage protection function.Overvoltage protecting unit is used for realizing over-voltage protecting function.There is pressing lock unit to have pressure automatic switching-in function for realizing inspection.By above-mentioned design, the utility model, aspect security protection, has overvoltage/undervoltage protection, examines functions such as there being the automatic closing of pressure.
As Fig. 2 and Fig. 3 have provided the further enforcement figure based on Fig. 1; under-voltage delay protection unit comprises under-voltage time delay module, device for under-voltage releasing equipment; the input of under-voltage time delay module connects power line; the output of under-voltage time delay module connects the input of device for under-voltage releasing equipment, the output connecting breaker of device for under-voltage releasing equipment.Under-voltage time delay module, device for under-voltage releasing equipment and circuit breaker are realized under-voltage protection function.Under-voltage time delay module be input as power voltage line; export to device for under-voltage releasing equipment power supply; in the time that line voltage is down to below the under-voltage value of setting; the output voltage of time delay module declines gradually; reach after delay time; device for under-voltage releasing equipment is threaded off, and drives breaker of plastic casing separating brake, thereby reaches the effect of under-voltage delay protection.Under-voltage release or relay refer in the time that the terminal voltage of release or relay is down to predetermined value, make mechanical switch electrical equipment have time delay or disconnect or closed release or relay without time delay.Under-voltage release or relay and device for switching are combined, and when applied voltage declines, even slow decreasing is to 70% to 35% scope of rated voltage, and under-voltage release or relay together with device for switching combination should move, and electrical equipment is disconnected.
Overvoltage protecting unit comprises the first motor-operating mechanism, the first input and output module, the first voltage monitor; the input of the first voltage monitor connects power line; the output of the first voltage monitor connects the input of the first input and output module; the output of the first input and output module connects the first motor-operating mechanism after light-coupled isolation, and the first motor-operating mechanism connecting breaker is to drive breaker open operation.The first voltage monitor is for obtaining voltage by power line; detect whether overvoltage of power voltage line, in the time line voltage overvoltage being detected, drive the first input and output module; after optocoupler carries out signal isolation, can drive motor-operating mechanism to drive breaker open operation, realize overvoltage protection.
There is pressing lock unit to comprise the second motor-operating mechanism, the second input and output module, second voltage monitoring modular, the input of second voltage monitoring modular connects power line, the output of second voltage monitoring modular connects the input of the second input and output module, the output of the second input and output module connects the second motor-operating mechanism after light-coupled isolation, and the second motor-operating mechanism connecting breaker is to drive breaker closing.After electrical network generation service restoration, second voltage monitoring modular obtains power voltage line, if voltage reaches the certain proportion value of electrical network rated voltage, such as 85%, will automatically send switching signal to input and output module, after optocoupler carries out signal isolation, can drive motor-operating mechanism to drive breaker closing, realizing inspection has pressure automatic switching-in function, need not manually remove closing by hand again.Motor-operating mechanism is a kind of for the remote device that circuit breaker is carried out to automatic brake separating and combined floodgate, not only can realize the remote breaking-closing operating of circuit breaker, can also realize the device of the Long-distance Control to circuit breaker.
In real process, described under-voltage delay protection unit, Overvoltage protecting unit, have pressing lock unit all can adopt example, in hardware realize, therefore make protected location reaction speed accelerate.
In addition, in order further to increase and to improve the utility model function, the utility model also comprises bidirectional measuring electric energy meter, and electric energy meter is arranged on power line.Bidirectional measuring electric energy meter is realized the function of measuring to energy output, also be responsible for gathering voltage, electric current, energy output simultaneously, the utility model also comprises lightning protection device, and the input of lightning protection device connects power line, and the output of lightning protection device connects the input of the first input and output module.Lightning protection device is realized the lightning protection to system, when equipment be struck by lightning and lightning protection device lost efficacy after, can send fault-signal to input and output module, after optocoupler carries out signal isolation, be sent to the first voltage monitoring module.
Further, the first voltage monitoring module of the present utility model is connected respectively wireless signal sending module and man-machine interface with second voltage monitoring modular.Man-machine interface is made up of liquid crystal display screen and two indicator lights, and liquid crystal display screen is realized the real-time Presentation Function of voltage, electric current, energy output etc., and two indicator lights represent that respectively breaker of plastic casing deciliter state and system have fault-free.
Wireless signal sending module is for sending to host computer by the information of voltage of the first voltage monitoring module and the detection of second voltage monitoring modular.
Fig. 4 has provided the further enforcement figure of the utility model based on Fig. 1 to Fig. 3, and in the utility model, the first voltage monitoring module and second voltage monitoring modular are just for distinguishing function of voltage monitoring, and actual, both can be a device form physically.Can certainly be still different physical units.Similarly, the first input and output module of the present utility model, the second input and output module, also, just as distinguishing in function, in reality, both can be a device form physically.Can certainly be still different physical units.In the utility model, the first motor-operating mechanism, the second motor-operating mechanism, be a device form in practice.
In Fig. 4, just provide hardware type of attachment more specifically.The first voltage monitoring module here and second voltage monitoring modular are all realized by controller and the bidirectional measuring electric energy meter of same set of physical form.The first input and output module, the second input and output module have adopted same set of input and output module physically, and the first motor-operating mechanism, the second motor-operating mechanism adopt same set of motor-operating mechanism.The controller here can select the most frequently used simple controller to realize.
Lightning protection device is realized the lightning protection to system, when equipment be struck by lightning and lightning protection device lost efficacy after, can send fault-signal to input and output module, after optocoupler carries out signal isolation, be sent to controller, controller is shown by liquid crystal.Motor-operating mechanism, input and output module, circuit breaker and controller are realized over-voltage protecting function.The information of voltage that controller can transmit according to electric energy meter judges whether overvoltage of system; when detect line voltage higher than set magnitude of voltage time; can send overvoltage protection signal to input and output module; after optocoupler carries out signal isolation, can drive motor-operating mechanism to drive breaker open operation, realize overvoltage protection.Motor-operating mechanism, input and output module, circuit breaker and controller are realized inspection pressure automatic switching-in function.After electrical network generation service restoration, controller can judge line voltage, if line voltage reaches 85% of rated voltage, will automatically send energization control signal to input and output module, after carrying out signal isolation, optocoupler can drive motor-operating mechanism to drive breaker closing, realizing inspection has pressure automatic switching-in function, need not manually remove closing by hand again.Man-machine interface is made up of liquid crystal display screen and two indicator lights, and liquid crystal display screen is realized the real-time Presentation Function of the information such as voltage, electric current, energy output, and two indicator lights represent that respectively breaker of plastic casing deciliter state and system have fault-free.Liquid crystal display screen obtains voltage, electric current, energy output and shows in real time from controller, facilitates user to check system information.
The utility model equipment, can realize the protection to distributed photovoltaic power generation site.Both unify distributed photovoltaic net mode, improved the fail safe of familial distribution of cases formula photovoltaic generation, can realize again the energy output statistics to photovoltaic generating system.It has feature: under-voltage delay protection function, delay time reaches as high as 10 seconds, the under-voltage 20%U that adjusts
n; Inspection has pressure automatic switching-in function, and inspection has repoussage to determine 85% of rated voltage; Function of measuring, the standard metering electric energy meter of the multiple meter reading method of configurable support, metering system energy output.Liquid crystal interface shows every generating data, facilitates user to consult the information such as energy output.Configuration lightning-protection module, possesses lightning protection function.Can carry out wireless communication with host computer.
The grid-connected protection equipment of distributed photovoltaic of the present utility model can make realization both unify distributed photovoltaic net mode to the protection of distributed photovoltaic power generation site; improve the fail safe of familial distribution of cases formula photovoltaic generation, can realize again monitoring and energy output statistics to photovoltaic generating system.
More than show and described general principle of the present utility model, principal character and advantage.The technical staff of the industry should understand, and above-described embodiment does not limit the utility model in any form, and all employings are equal to replaces or technical scheme that the mode of equivalent transformation obtains, all drops in protection range of the present utility model.
Claims (7)
1. the grid-connected protection equipment of distributed photovoltaic, is arranged on the power line that connects distributed photovoltaic power generation system and power distribution network, it is characterized in that, comprising: circuit breaker, under-voltage delay protection unit, Overvoltage protecting unit, have pressing lock unit; Described circuit breaker is arranged on power line; The input of described under-voltage delay protection unit connects power line, and the output connecting breaker of under-voltage delay protection unit is so that breaker open operation; The input of described Overvoltage protecting unit connects power line, and the output connecting breaker of described Overvoltage protecting unit is so that breaker open operation; The described input that has pressing lock unit connects power line, has the output connecting breaker of pressing lock unit so that breaker closing.
2. the grid-connected protection equipment of distributed photovoltaic according to claim 1; it is characterized in that; described under-voltage delay protection unit comprises under-voltage time delay module, device for under-voltage releasing equipment; the input of under-voltage time delay module connects power line; the output of under-voltage time delay module connects the input of device for under-voltage releasing equipment, the output connecting breaker of device for under-voltage releasing equipment.
3. the grid-connected protection equipment of distributed photovoltaic according to claim 1; it is characterized in that; described Overvoltage protecting unit comprises the first motor-operating mechanism, the first input and output module, the first voltage monitor; the input of described the first voltage monitor connects power line; the output of the first voltage monitor connects the input of the first input and output module; the output of the first input and output module connects the first motor-operating mechanism after light-coupled isolation, and the first motor-operating mechanism connecting breaker is to drive breaker open operation.
4. the grid-connected protection equipment of distributed photovoltaic according to claim 1; it is characterized in that; described have pressing lock unit to comprise the second motor-operating mechanism, the second input and output module, second voltage monitoring modular; the input of described second voltage monitoring modular connects power line; the output of described second voltage monitoring modular connects the input of the second input and output module; the output of described the second input and output module connects the second motor-operating mechanism after light-coupled isolation, and the second motor-operating mechanism connecting breaker is to drive breaker closing.
5. according to the grid-connected protection equipment of the distributed photovoltaic described in claim 1 to 4 any one, it is characterized in that, also comprise bidirectional measuring electric energy meter, described electric energy meter is arranged on power line.
6. the grid-connected protection equipment of distributed photovoltaic according to claim 5, is characterized in that, also comprises lightning protection device, and the input of described lightning protection device connects power line, and the input of module is outputed in the output connection first of described lightning protection device.
7. the grid-connected protection equipment of distributed photovoltaic according to claim 5, is characterized in that, described the first voltage monitoring module is connected respectively wireless signal sending module and man-machine interface with second voltage monitoring modular.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420199834.5U CN203911498U (en) | 2014-04-23 | 2014-04-23 | Distributed photovoltaic grid-connected protective equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420199834.5U CN203911498U (en) | 2014-04-23 | 2014-04-23 | Distributed photovoltaic grid-connected protective equipment |
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| Publication Number | Publication Date |
|---|---|
| CN203911498U true CN203911498U (en) | 2014-10-29 |
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ID=51785744
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420199834.5U Expired - Fee Related CN203911498U (en) | 2014-04-23 | 2014-04-23 | Distributed photovoltaic grid-connected protective equipment |
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| Country | Link |
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| CN (1) | CN203911498U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103972925A (en) * | 2014-04-23 | 2014-08-06 | 南京南瑞太阳能科技有限公司 | Distributed photovoltaic grid connection protective device |
| CN104753045A (en) * | 2015-04-15 | 2015-07-01 | 国家电网公司 | Distributed photovoltaic grid-connection safeguard system |
-
2014
- 2014-04-23 CN CN201420199834.5U patent/CN203911498U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103972925A (en) * | 2014-04-23 | 2014-08-06 | 南京南瑞太阳能科技有限公司 | Distributed photovoltaic grid connection protective device |
| CN103972925B (en) * | 2014-04-23 | 2016-03-30 | 南京南瑞太阳能科技有限公司 | The grid-connected proterctive equipment of distributed photovoltaic |
| CN104753045A (en) * | 2015-04-15 | 2015-07-01 | 国家电网公司 | Distributed photovoltaic grid-connection safeguard system |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20141029 Termination date: 20200423 |