CN205792453U - A kind of distributed photovoltaic system online insulation against ground safety monitoring assembly - Google Patents
A kind of distributed photovoltaic system online insulation against ground safety monitoring assembly Download PDFInfo
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- CN205792453U CN205792453U CN201620425639.9U CN201620425639U CN205792453U CN 205792453 U CN205792453 U CN 205792453U CN 201620425639 U CN201620425639 U CN 201620425639U CN 205792453 U CN205792453 U CN 205792453U
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Abstract
This utility model provides a kind of distributed photovoltaic system online insulation against ground safety monitoring assembly, and it includes that bus current detection module, busbar voltage detection module, over the ground current acquisition module, Ground leakage current acquisition module, switching signal input/output module, central authorities control processing module, communication module, relay control module, minus earth unit, negative power supply unit and run indicating module；Central authorities control processing module and receive voltage, the current information that corresponding module gathers; calculate and judge whether the insulation against ground resistance value of photovoltaic system square formation and Ground leakage current transfinite, exporting the instruction of corresponding protection act when judging to transfinite to on-off model input/output module and relay control module.This utility model can realize insulation safety round-the-clock to photovoltaic system square formation protection, and effective guarantee photovoltaic system runs safety.
Description
Technical field
This utility model relates to distributed photovoltaic technical field, is specifically related to distributed photovoltaic system online insulation against ground safety monitoring assembly.
Background technology
In recent years, the application of distributed photovoltaic system generating is more and more extensive, and it has the effect of the shortage alleviating conventional energy resource and the pollution reducing environment.Along with distributed photovoltaic application is more and more, power plant scale is increasing, and the number of assembly series connection constantly increases.Distributed photovoltaic system major part is installed on roof simultaneously, it is in unmanned, the state of periodic maintenance maintenance, and at present photovoltaic system DC side insulation safety is only monitored when inverter startup, photovoltaic system in power generation process without real-time insulation safety monitoring function.There is insulation safety problem in system one, can not be found in time, have a strong impact on the safety of photovoltaic plant, be likely to result in serious personnel's property injury, power station investment return is caused irremediable loss, and monitoring distributed photovoltaic safe insulation problem is necessary the most in real time.
Utility model content
The purpose of this utility model is: for above-mentioned technical problem, utility model a kind of distributed photovoltaic system online insulation against ground safety monitoring assembly, it is in use, the insulation against ground security situation of energy real time on-line monitoring photovoltaic module matrix when photovoltaic system is in generator operation, it is possible to realize the insulation safety monitoring of photovoltaic module matrix when photovoltaic DC-to-AC converter does not works；By monitoring the insulation impedance situation of photovoltaic system square formation, it is achieved the insulation safety of photovoltaic system square formation is protected, thus is effectively improved the reliability of photovoltaic system, ensure that photovoltaic system runs safety.
The technical solution of the utility model is: distributed photovoltaic system of the present utility model online insulation against ground safety monitoring assembly, and it is structurally characterized in that: include that bus current detection module, busbar voltage detection module, over the ground current acquisition module, Ground leakage current acquisition module, switching signal input/output module, central authorities control processing module, communication module, relay control module, minus earth unit, negative power supply unit and run indicating module；Wherein:
Bus current sampling module, is used for gathering DC side positive electrode bus current signal, and the current signal of sampling is sent to central authorities' control processing module；The input of bus current sampling module is electrically connected with DC side positive electrode bus by current transformer；The outfan of bus current sampling module controls processing module with central authorities and electrically connects；
Busbar voltage sampling module, is used for gathering photovoltaic system voltage signal, and the voltage signal of sampling is sent to central authorities' control processing module；3 inputs of busbar voltage sampling module common junction with the DC side positive electrode bus of tested photovoltaic system square formation, DC side negative electrode bus and the positive pole resistance to earth of tested photovoltaic system square formation and negative pole resistance to earth common ground respectively electrically connects；The outfan of busbar voltage sampling module controls processing module with central authorities and electrically connects；
Minus earth unit, is used for providing different voltage sources and online virtual variable resistance；The input of minus earth unit electrically connects with DC side negative electrode bus；
Negative power supply unit, for realizing minus earth and the switching of negative power supply module and direct current arc extinguishing；The input of negative power supply unit electrically connects with the outfan of minus earth unit；The outfan of negative power supply unit controls processing module with central authorities and electrically connects；The earth terminal ground connection of negative power supply unit；
Current acquisition module over the ground, for detecting the earth current of negative power supply unit, the input of current acquisition module is electrically connected with the earth terminal of negative power supply unit by current transformer over the ground；The outfan of current acquisition module electrically connects with the central processing module that controls over the ground；
Ground leakage current acquisition module, for gathering the Ground leakage current of photovoltaic system square formation DC side bus；Ground leakage current acquisition module is electrically connected with photovoltaic system square formation DC side positive electrode bus and DC side negative electrode bus by current transformer；The outfan of Ground leakage current acquisition module controls processing module with central authorities and electrically connects；
On-off model input/output module, for realizing the interconnection with photovoltaic system associated external equipment；On-off model input/output module controls processing module with central authorities and electrically connects；
Communication module, mutual with the remote information on backstage for realizing；Communication module controls processing module two-way signaling with central authorities and electrically connects；
Relay control module, for controlling the corresponding switching controlling photovoltaic system square formation dc bus of instruction and the disconnection isolation of photovoltaic generation power changer of processing module according to central authorities；
Run indicating module, for the running status of display device；The input running indicating module electrically connects with the central processing module that controls；
Central authorities control processing module; for receiving the voltage of collection, current information; calculate and judge whether the insulation against ground resistance value of photovoltaic system square formation and Ground leakage current transfinite, exporting the instruction of corresponding protection act when judging to transfinite to on-off model input/output module and relay control module.
This utility model has a positive effect: distributed photovoltaic system of the present utility model online insulation against ground safety monitoring assembly; it is in use; by the voltage relevant to photovoltaic system square formation, the corresponding information gathering acquisition photovoltaic system square formation of current signal; the state of insulation of automatic decision photovoltaic system square formation, automatically makes when judging and transfiniting and performs the protection act being correlated with；Thus realize the round-the-clock insulation safety to photovoltaic system square formation and protect, effective guarantee photovoltaic system runs safety；Meanwhile, background work personnel also can conveniently realize the long-range monitoring to photovoltaic arrays system insulation safe condition.
Accompanying drawing explanation
Fig. 1 is circuit structure schematic block diagram of the present utility model, figure also schematically illustrates its in use with the electrical connection of photovoltaic system square formation.
Reference in above-mentioned accompanying drawing is as follows:
Bus current detection module 1, busbar voltage detection module 2, current acquisition module 3 over the ground, Ground leakage current acquisition module 4, switching signal input/output module 5, central authorities control processing module 6, communication module 7, relay control module 8, minus earth unit 9, negative power supply unit 10, runs indicating module 11.
Detailed description of the invention
With detailed description of the invention, this utility model is described in further detail below in conjunction with the accompanying drawings.
(embodiment 1)
See Fig. 1, the distributed photovoltaic system online insulation against ground safety monitoring assembly of the present embodiment, it is used for the online insulation against ground safety monitoring of distributed photovoltaic system, and distributed photovoltaic system has the DC side negative electrode bus between photovoltaic system square formation, photovoltaic generation power changer, the DC side positive electrode bus and the dc bus negative pole (PV-) being connected to photovoltaic system square formation and photovoltaic generation power changer that are connected between the dc bus positive pole (PV+) of photovoltaic system square formation and photovoltaic generation power changer (photovoltaic DC-to-AC converter)；Photovoltaic system square formation has positive pole resistance to earth Rpv+, and during work, pressure drop thereon is Upv+；One end of positive pole resistance to earth Rpv+ electrically connects with DC side positive electrode bus；Photovoltaic system square formation has negative pole resistance to earth Rpv-, and during work, pressure drop thereon is Upv-；One end of negative pole resistance to earth Rpv-electrically connects with DC side negative electrode bus；The other end of positive pole resistance to earth Rpv+ has common junction and this common junction ground connection with the other end of negative pole resistance to earth Rpv-.
The distributed photovoltaic system online insulation against ground safety monitoring assembly of the present embodiment, it is mainly controlled processing module 6, communication module 7, relay control module 8, minus earth unit 9, negative power supply unit 10 and operation indicating module 11 formed by bus current detection module 1, busbar voltage detection module 2, over the ground current acquisition module 3, Ground leakage current acquisition module 4, switching signal input/output module 5, central authorities.
Bus current sampling module 1, is used for gathering DC side positive electrode bus current signal i1, and the current signal of sampling is sent to central authorities' control processing module 6；The input of bus current sampling module 1 is electrically connected with DC side positive electrode bus by current transformer；The outfan of bus current sampling module 1 controls processing module 6 with central authorities and electrically connects.
Busbar voltage sampling module 2, is used for gathering photovoltaic system voltage signal, and the voltage signal of sampling is sent to central authorities' control processing module 6；3 inputs of busbar voltage sampling module 2 common junction with the positive pole resistance to earth Rpv+ and negative pole resistance to earth Rpv-of DC side positive electrode bus, DC side negative electrode bus and photovoltaic system square formation respectively electrically connects；The outfan of busbar voltage sampling module 2 controls processing module 6 with central authorities and electrically connects.
Minus earth unit 9, is used for providing different voltage sources and online virtual variable resistance Rvr, participates in insulation against ground computing the resistor value；The input of minus earth unit 9 electrically connects with DC side negative electrode bus.
Negative power supply unit 10, for realizing minus earth and the switching of negative power supply module and direct current arc-suppression function；The input of negative power supply unit 10 electrically connects with the outfan of minus earth unit 9；The outfan of negative power supply unit 10 controls processing module 6 with central authorities and electrically connects；The earth terminal ground connection of negative power supply unit 10.
Current acquisition module 3 over the ground, for detecting the earth current i4 of negative power supply unit 10, the input of current acquisition module 3 is electrically connected with the earth terminal of negative power supply unit 10 by current transformer over the ground；The outfan of current acquisition module 3 electrically connects with the central processing module 6 that controls over the ground.
Ground leakage current acquisition module 4, for gathering the Ground leakage current (i1-i2) of the dc bus of photovoltaic system square formation；Ground leakage current acquisition module 4 is electrically connected with DC side positive electrode bus and DC side negative electrode bus by current transformer；The outfan of Ground leakage current acquisition module 4 controls processing module 6 with central authorities and electrically connects.
On-off model input/output module 5, for realizing external equipment corresponding with photovoltaic system such as sound and light alarm equipment, the interconnection of photovoltaic generation power changer；On-off model input/output module 5 controls processing module 6 with central authorities and electrically connects.
Communication module 7, mutual with the remote information on backstage for realizing；Communication module 7 controls processing module 6 two-way signaling with central authorities and electrically connects.
Relay control module 8, for controlling the corresponding switching controlling photovoltaic system square formation dc bus of instruction and the disconnection isolation of photovoltaic generation power changer of processing module 6 according to central authorities, cuts off warping apparatus in time and realizes the safe insulation protection of system.
Run indicating module 11, for the running status of display device；The input running indicating module 11 electrically connects with the central processing module 6 that controls.
Central authorities control processing module 6, for receiving the voltage of collection, current information, calculate and judge whether the insulation against ground resistance value of photovoltaic system square formation and Ground leakage current transfinite, providing alarm signal when judging photovoltaic system Abnormal Insulation by on-off model input/output module 5；When judging the Ground leakage current (i1-i2) gathered less than maximum leakage current setting value, judge, inside photovoltaic generation power changer, Insulation Problems occurs, disconnect photovoltaic generation power changer by relay control module Final 8 system and be at isolation, it is ensured that system insulation safety.
The distributed photovoltaic system online insulation against ground safety monitoring assembly of the present embodiment, its operation principle is summarized as follows:
The detection of the positive pole resistance to earth Rpv+ of photovoltaic system square formation:
Negative power supply unit 10 changes inside Rvr over the ground so that it is be 0 ohm, then negative pole voltage-to-ground is 0, i.e. Upv-=0；Minus earth unit 9 is started working, negative pole is made to be connected with the earth by direct current arc-suppression circuit, current sample module 3 detects electric current i4 over the ground, busbar voltage acquisition module 2 gathers positive pole voltage-to-ground Upv+, now, due to negative pole short circuit over the ground, Rpv-equivalent parallel 0 ohmage, it is (i1-i2) that Ground leakage current acquisition module 4 gathers Ground leakage current, so positive pole equivalence resistance to earth Req+ is:
Req+= Upv+/[i4+(i1-i2)]；
If photovoltaic generation power changer resistance to earth is Rs+, then have:
Rs+=Upv+/(i1-i2)；
Because Rpv+ with Rs+ is in parallel, can obtain:
1/(Rs+)+1/(Rpv+)=1/ (Req+)；
Then have:
Rpv+ =[(Rs+)×(Req+)]/[(Rs+)-(Req+)]；
The detection of the negative pole resistance to earth Rpv-of photovoltaic system square formation:
Negative power supply unit 10 changes inside Rvr over the ground, it is made to be far longer than photovoltaic resistance to earth Rpv-, now i4=0, busbar voltage acquisition module 2 detects photovoltaic system square formation positive pole voltage-to-ground Upv+ and negative pole voltage-to-ground Upv-, then DC bus-bar voltage is: Upv=(Upv+)+(Upv-), and now negative pole voltage-to-ground is:
Upv-=Upv × (Rpv-)/[(Rpv+)+(Rpv-)]；
Rpv-can be obtained by above formula:
Rpv-=(Rpv+)× Upv-/[(Upv)+(Upv-)]。
Above-mentioned calculating is controlled processing module 6 by central authorities and utilizes the Automatic Program of built-in prior art to carry out.
Central authorities control processing module 6 and photovoltaic system insulation safety judge and make accordingly action:
Central authorities control processing module 6 and are built-in with the minimum judgment threshold of photovoltaic system square formation insulation against ground resistance Rpv+ and Rpv-, when the detection value of calculation of Rpv+, Rpv-is less than minimum judgment threshold, central authorities control processing module 6 and provide alarm signal by on-off model input/output module 5, drive sound and light alarm to ensure the safety of the personnel of power station operation；Central authorities control processing module 6 and are built-in with the maximum leakage current decision threshold of setting, when central authorities' control processing module 6 judges current Ground leakage current collection (i1-i2) less than the maximum leakage current decision threshold set, then central authorities' control processing module 6 judges Insulation Problems occur inside photovoltaic generation power changer, photovoltaic generation power inverter off order is given by on-off model input/output module 5, disconnect photovoltaic generation power changer by relay control module Final 8 system and be at isolation, it is ensured that system insulation safety.
Above example is the explanation to detailed description of the invention of the present utility model; rather than to restriction of the present utility model; person skilled in the relevant technique is in the case of without departing from spirit and scope of the present utility model; can also make various conversion and change and obtain the technical scheme of corresponding equivalent, the technical scheme of the most all equivalents all should be included into scope of patent protection of the present utility model.
Claims (1)
1. a distributed photovoltaic system online insulation against ground safety monitoring assembly, it is characterised in that: include that bus current detection module, busbar voltage detection module, over the ground current acquisition module, Ground leakage current acquisition module, switching signal input/output module, central authorities control processing module, communication module, relay control module, minus earth unit, negative power supply unit and run indicating module；Wherein:
Bus current sampling module, is used for gathering DC side positive electrode bus current signal, and the current signal of sampling is sent to central authorities' control processing module；The input of bus current sampling module is electrically connected with DC side positive electrode bus by current transformer；The outfan of bus current sampling module controls processing module with central authorities and electrically connects；
Busbar voltage sampling module, is used for gathering photovoltaic system voltage signal, and the voltage signal of sampling is sent to central authorities' control processing module；3 inputs of busbar voltage sampling module common junction with the DC side positive electrode bus of tested photovoltaic system square formation, DC side negative electrode bus and the positive pole resistance to earth of tested photovoltaic system square formation and negative pole resistance to earth common ground respectively electrically connects；The outfan of busbar voltage sampling module controls processing module with central authorities and electrically connects；
Minus earth unit, is used for providing different voltage sources and online virtual variable resistance；The input of minus earth unit electrically connects with DC side negative electrode bus；
Negative power supply unit, for realizing minus earth and the switching of negative power supply module and direct current arc extinguishing；The input of negative power supply unit electrically connects with the outfan of minus earth unit；The outfan of negative power supply unit controls processing module with central authorities and electrically connects；The earth terminal ground connection of negative power supply unit；
Current acquisition module over the ground, for detecting the earth current of negative power supply unit, the input of current acquisition module is electrically connected with the earth terminal of negative power supply unit by current transformer over the ground；The outfan of current acquisition module electrically connects with the central processing module that controls over the ground；
Ground leakage current acquisition module, for gathering the Ground leakage current of photovoltaic system square formation DC side bus；Ground leakage current acquisition module is electrically connected with photovoltaic system square formation DC side positive electrode bus and DC side negative electrode bus by current transformer；The outfan of Ground leakage current acquisition module controls processing module with central authorities and electrically connects；
On-off model input/output module, for realizing the interconnection with photovoltaic system associated external equipment；On-off model input/output module controls processing module with central authorities and electrically connects；
Communication module, mutual with the remote information on backstage for realizing；Communication module controls processing module two-way signaling with central authorities and electrically connects；
Relay control module, for controlling the corresponding switching controlling photovoltaic system square formation dc bus of instruction and the disconnection isolation of photovoltaic generation power changer of processing module according to central authorities；
Run indicating module, for the running status of display device；The input running indicating module electrically connects with the central processing module that controls；
Central authorities control processing module; for receiving the voltage of collection, current information; calculate and judge whether the insulation against ground resistance value of photovoltaic system square formation and Ground leakage current transfinite, exporting the instruction of corresponding protection act when judging to transfinite to on-off model input/output module and relay control module.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106018967A (en) * | 2016-05-12 | 2016-10-12 | 国网江苏省电力公司常州供电公司 | On-line ground insulating security monitoring device for distributed photovoltaic system |
| CN110708016A (en) * | 2019-10-22 | 2020-01-17 | 阳光电源股份有限公司 | Method and device for monitoring insulation performance of photovoltaic grid-connected power generation system |
| WO2021057037A1 (en) * | 2019-09-24 | 2021-04-01 | 华为技术有限公司 | Photovoltaic power generation system and method |
| CN112924753A (en) * | 2019-12-06 | 2021-06-08 | 苏州阿特斯阳光电力科技有限公司 | Detection apparatus for photovoltaic array is to ground insulation resistance |
| CN113138326A (en) * | 2021-05-12 | 2021-07-20 | 阳光电源股份有限公司 | Insulation detection system, insulation detection method and photovoltaic system |
-
2016
- 2016-05-12 CN CN201620425639.9U patent/CN205792453U/en not_active Expired - Fee Related
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106018967A (en) * | 2016-05-12 | 2016-10-12 | 国网江苏省电力公司常州供电公司 | On-line ground insulating security monitoring device for distributed photovoltaic system |
| CN106018967B (en) * | 2016-05-12 | 2018-03-20 | 国网江苏省电力公司常州供电公司 | The online insulation against ground safety monitoring assembly of distributed photovoltaic system |
| WO2021057037A1 (en) * | 2019-09-24 | 2021-04-01 | 华为技术有限公司 | Photovoltaic power generation system and method |
| CN110708016A (en) * | 2019-10-22 | 2020-01-17 | 阳光电源股份有限公司 | Method and device for monitoring insulation performance of photovoltaic grid-connected power generation system |
| CN110708016B (en) * | 2019-10-22 | 2023-02-03 | 阳光电源股份有限公司 | Method and device for monitoring insulation performance of photovoltaic grid-connected power generation system |
| CN112924753A (en) * | 2019-12-06 | 2021-06-08 | 苏州阿特斯阳光电力科技有限公司 | Detection apparatus for photovoltaic array is to ground insulation resistance |
| CN112924753B (en) * | 2019-12-06 | 2022-09-16 | 苏州阿特斯阳光电力科技有限公司 | Detection apparatus for photovoltaic array is to ground insulation resistance |
| CN113138326A (en) * | 2021-05-12 | 2021-07-20 | 阳光电源股份有限公司 | Insulation detection system, insulation detection method and photovoltaic system |
| CN113138326B (en) * | 2021-05-12 | 2024-05-14 | 阳光电源股份有限公司 | Insulation detection system, insulation detection method and photovoltaic system |
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Granted publication date: 20161207 |