CN103248007A - PID (Potential Induced Degradation)-resistant circuit and monitoring device thereof - Google Patents
PID (Potential Induced Degradation)-resistant circuit and monitoring device thereof Download PDFInfo
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- CN103248007A CN103248007A CN2013101868163A CN201310186816A CN103248007A CN 103248007 A CN103248007 A CN 103248007A CN 2013101868163 A CN2013101868163 A CN 2013101868163A CN 201310186816 A CN201310186816 A CN 201310186816A CN 103248007 A CN103248007 A CN 103248007A
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Abstract
The invention discloses a PID (Potential Induced Degradation)-resistant circuit and a monitoring device thereof. The PID-resistant circuit comprises a photovoltaic cell, an inverter and a ground circuit, wherein the anode of the photovoltaic cell is connected with the anode of the direct-current input of the inverter through an anode relay; the cathode of the photovoltaic cell is connected with the cathode of the direct-current input of the inverter through a cathode relay; the ground circuit comprises a fusing protection circuit and a current sensor; the fusing protection circuit consists of a fuse and a protective resistor which are connected in parallel; and one end of the ground circuit is connected with the cathode of the direct-current input of the inverter, and the other end of the ground circuit passing through the fusing protection circuit and the current sensor is grounded. Due to the adoption of the PID-resistant circuit, the phenomenon of PID existing in a photovoltaic cell panel can be eliminated effectively; and meanwhile, ground leakage protection and detection are performed on an entire photovoltaic cell panel array, so that electric shock accidents are avoided and rapid detection of ground short-circuit fault is realized.
Description
Technical field
The present invention relates to photovoltaic battery panel and earthed circuit.
Background technology
PID is the abbreviation of English " Potential induced degradation ", and namely potential electromotive force is induced decay, is the peculiar image of solar panel.Be that the famous Sunpower company of photovoltaic manufacturer of the U.S. found in 2005 the earliest; many enterprises and scientific research institution are after finding the PID phenomenon both at home and abroad; carried out research in various degree from aspects such as modular constructions; but all can not effectively solve the PID phenomenon; reduced the energy output of photovoltaic plant in hot and humid area to a great extent; make the development of photovoltaic plant in the coastal region in east China be subjected to serious obstruction; the present invention program starts with from photovoltaic system; effectively controlled the generation of PID phenomenon by the mode of minus earth; and multinomial safeguard measure is installed; increase security of system, successfully captured this technical barrier both domestic and external.
Solar cell panel assembly is over the ground under the back bias voltage effect, make and have leakage current between glass, the encapsulating material, a large amount of accumulation are on battery sheet surface, the passivation effect of battery surface worsens, cause activity coefficient FF, reducing appears in short circuit current Isc, open circuit voltage Voc, makes the performance of assembly be lower than design standard.Through observation, solar cell panel assembly can produce 40% performance degradation in two years under long-term back bias voltage effect.Also confirmed the P type crystal silicon battery sheet no matter which kind of technology battery panel components adopts in NREL in 2010 and Solon company, all there is the risk of PID in assembly under back bias voltage situation over the ground.
The main cause that produces PID is relevant with composite factors such as cell panel self characteristics, grid-connected system characteristic, inverter style, external temperature, humidity, battery earthing modes.Generally, present over the ground under the back bias voltage situation, the extraneous cell panel that environment such as high temperature, high humidity occur more is easy to generate the PID phenomenon simultaneously.So cell panel PID phenomenon usually occurs in the early morning of dew or mist, perhaps behind the rain on daytime.The PID degree of the battery panel components of different brands also can be different simultaneously.Back bias voltage is more big over the ground for cell panel in addition, and the PID phenomenon is more serious.
The factor that influenced by the PID phenomenon has reversible polarity effect and irreversible electrical erosion.Reversible polarity effect can be recovered, and after the assembly surface cleaning drying, polarity effect can disappear, and can not cause permanent damage to cell panel.Irreversible electrical erosion is subjected to temperature, the humidity effect of environment.
Because the PID problem is because the photovoltaic cell board component presents back bias voltage over the ground and causes, and therefore can eliminate the PID problem by the mode of photovoltaic cell board component minus earth.
Summary of the invention
Problem to be solved by this invention is to eliminate and prevention photovoltaic battery panel PID problem, and photovoltaic battery panel is carried out detection of electrical leakage and protection.
For addressing the above problem, the scheme that the present invention adopts is as follows:
A kind of anti-PID circuit comprises photovoltaic cell, inverter; Photovoltaic cell is anodal to link to each other by the positive pole of anodal relay with the input of inverter direct current; The photovoltaic cell negative pole links to each other by the negative pole of negative pole relay with the input of inverter direct current; It is characterized in that it also comprises earthed circuit; Described earthed circuit comprises the fuse protection circuit; Described fuse protection circuit is made up of fuse and the protective resistance of parallel connection; The negative pole of the one termination inverter direct current input of described earthed circuit is through described fuse protection circuit, other end ground connection.
Further, described earthed circuit also comprises current sensor, and described current sensor one end connects described fuse protection circuit, other end ground connection.
Further, described anodal relay is connected supervising device with the negative pole relay with current sensor, realizes the photovoltaic cell board component is carried out long-range electric leakage monitoring, and carries out error protection.
Further, described earthed circuit also comprises cathode voltage transducer and cathode voltage transducer; The positive pole of described cathode voltage transducer one termination inverter direct current input, other end ground connection; The negative pole of described cathode voltage transducer one termination inverter direct current input, other end ground connection; Described cathode voltage transducer is connected supervising device with the cathode voltage transducer.
A kind of supervising device; it connects above-mentioned anodal relay, negative pole relay, current sensor, cathode voltage transducer and cathode voltage transducer; it is by the analysis of data that current sensor, cathode voltage transducer, cathode voltage sensor passes are come; judge the electric leakage situation of photovoltaic battery panel, and the switch control of anodal relay and negative pole relay is realized the protection of photovoltaic battery panel.
Technique effect of the present invention is:
1, by the ground connection to photovoltaic cell board component negative pole, eliminates and prevention PID problem.
2, by the fusing fuse is installed, realize electrical shock protection in earthed circuit.
3, by current sensor is installed in the earthed circuit, monitor photovoltaic battery panel electric leakage situation, leak electricity when excessive, by controlling the folding protection photovoltaic battery panel of anodal relay and negative pole relay, even and can safeguard photovoltaic battery panel.
4, by the monitoring to anodal voltage to earth and negative pole voltage to earth, analyze the electric leakage situation.
Actual benefit of the present invention and influence:
1, increases the actual motion life-span of solar components, reduce attenuation rate, reduce replacement of component quantity in service, reduced the operating cost of photovoltaic plant.
2, improve coastal region in east China photovoltaic power station power generation amount, increased the economic well-being of workers and staff of photovoltaic plant in the coastal region in east China.The large-sized photovoltaic power station is able in coastal hot and humid regional large-scale popularization.
3, increase the DC side protection system, prevent that security incident from taking place.
Description of drawings
Fig. 1 is electrical block diagram of the present invention.
Embodiment
Below in conjunction with accompanying drawing the present invention is described in further details.
As shown in Figure 1, a kind of anti-PID circuit comprises photovoltaic cell VC, inverter DA, earthed circuit.The positive pole of photovoltaic cell VC connects the positive pole of inverter DA direct current input through anodal relay SW1.Photovoltaic cell VC is solar panel array.The negative pole of photovoltaic cell VC connects the negative pole of inverter DA direct current input through negative pole relay SW2.Inverter DA sends alternating current into the public VSS of supply line after converting direct current to alternating current.Earthed circuit is connected between the negative pole and negative pole relay SW2 of inverter DA direct current input.Earthed circuit comprises fuse protection circuit and current sensor PA.Fuse F and protective resistance R form in the fuse protection electricity routing diagram.Fuse F and protective resistance R parallel connection.Fuse protection circuit and current sensor PA series connection.The negative pole of the one termination inverter DA direct current input of fuse protection circuit, another termination current sensor PA.Current sensor PA, a termination fuse protection circuit, other end ground connection G..That is, the negative pole of a termination inverter DA direct current of earthed circuit input, through described fuse protection circuit, other end ground connection G.Anodal relay SW1 and negative pole relay SW2, and current sensor PA links to each other with supervising device by network.Be the state that supervising device can obtain anodal relay SW1 and negative pole relay SW2, also can directly control the switch of anodal relay SW1 and negative pole relay SW2.The current data that current sensor PA monitors is sent to supervising device by network.
Under the said structure, further, earthed circuit of the present invention also comprises cathode voltage transducer PV1 and cathode voltage transducer PV2; The positive pole of cathode voltage transducer PV1 one termination inverter DA direct current input, other end ground connection G..The negative pole of cathode voltage transducer PV2 one termination inverter DA direct current input, other end ground connection.Cathode voltage transducer PV1 links to each other with supervising device with cathode voltage transducer PV2.Cathode voltage transducer PV1 and cathode voltage transducer PV2 are respectively applied to measure the voltage to earth of photovoltaic battery panel positive pole and negative pole.
Under the foregoing circuit structure, when the photovoltaic battery panel positive pole was short-circuited with ground connection, photovoltaic battery panel positive pole, ground connection, fuse, photovoltaic battery panel negative pole formed the loop, and fuse blows the loop, back and disconnects, thereby protects photovoltaic battery panel.Protective resistance R is big impedance resistance, and after fuse blew, protective resistance is ground connection still, thereby makes photovoltaic battery panel negative pole ground connection still, eliminates PID.On the other hand; take place under the situation of electric leakage with ground connection when photovoltaic battery panel is anodal; this situation may be that human electric shock or contact short circuit take place; photovoltaic battery panel positive pole, ground connection, fuse, photovoltaic battery panel negative pole form loop of electric leakage; current sensor PA can monitor leakage current; supervising device receives the leakage current that current sensor PA sends; if leakage current exceeds certain limit; supervising device can directly disconnect negative pole relay SW2; thereby protect photovoltaic battery panel and personal security, and notify the staff to safeguard by warning system.Further, supervising device is also gathered the voltage to earth of photovoltaic battery panel positive pole and negative pole.By the analysis to anodal negative pole voltage to earth, and the analysis of mesh current can further judge the electric leakage situation of photovoltaic battery panel, and the direct measurement of this analysis and front is complementary mutually, also is the further analysis to front photovoltaic cell board status.
The foregoing circuit structure can be arranged on above-mentioned earthed circuit in the header box in the specific implementation.Header box is in order to reduce the line between solar-energy photo-voltaic cell array and the inverter.Photovoltaic battery array can be divided into groups in the header box, every group of negative pole is connected the header box casing, the ground connection of header box casing own behind a fuse protection circuit and current sensor.
Supervising device generally is to be made of long-range control host machine and the software systems that run on the main frame, and the software systems of this supervising device also can directly be integrated in the telecontrol system, as the part of power monitoring.
Claims (6)
1. an anti-PID circuit comprises photovoltaic cell, inverter; Photovoltaic cell is anodal to link to each other by the positive pole of anodal relay with the input of inverter direct current; The photovoltaic cell negative pole links to each other by the negative pole of negative pole relay with the input of inverter direct current; It is characterized in that it also comprises earthed circuit; Described earthed circuit comprises the fuse protection circuit; Described fuse protection circuit is made up of fuse and the protective resistance of parallel connection; The negative pole of the one termination inverter direct current input of described earthed circuit is through described fuse protection circuit, other end ground connection.
2. anti-PID circuit as claimed in claim 1 is characterized in that described earthed circuit also comprises current sensor, and described current sensor one end connects described fuse protection circuit, other end ground connection.
3. anti-PID circuit as claimed in claim 1 is characterized in that, described anodal relay is connected supervising device with the negative pole relay.
4. anti-PID circuit as claimed in claim 2 is characterized in that, described anodal relay is connected supervising device with the negative pole relay with current sensor.
5. anti-PID circuit as claimed in claim 4 is characterized in that, described earthed circuit also comprises cathode voltage transducer and cathode voltage transducer; The positive pole of described cathode voltage transducer one termination inverter direct current input, other end ground connection; The negative pole of described cathode voltage transducer one termination inverter direct current input, other end ground connection; Described cathode voltage transducer is connected supervising device with the cathode voltage transducer.
6. supervising device; it is characterized in that; it connects the described anodal relay of claim 5, negative pole relay, current sensor, cathode voltage transducer and cathode voltage transducer; it is by the analysis of data that current sensor, cathode voltage transducer, cathode voltage sensor passes are come; judge the electric leakage situation of photovoltaic battery panel, and the switch control of anodal relay and negative pole relay is realized the protection of photovoltaic battery panel.
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Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103475208A (en) * | 2013-09-18 | 2013-12-25 | 江苏兆伏新能源有限公司 | PID suppression circuit of photovoltaic system |
| CN103490402A (en) * | 2013-09-05 | 2014-01-01 | 南京南瑞继保电气有限公司 | Photovoltaic module grounding device, photovoltaic module grounding monitoring device and monitoring method |
| CN103607172A (en) * | 2013-12-05 | 2014-02-26 | 无锡上能新能源有限公司 | Device for simultaneously realizing negative grounding and ground insulation resistance detection in photovoltaic power station |
| CN103647504A (en) * | 2013-12-17 | 2014-03-19 | 刘继茂 | Solar cell grounding device and method |
| CN103701150A (en) * | 2013-12-26 | 2014-04-02 | 华为技术有限公司 | Multi-unit parallel circuit, power supply system and voltage regulation method |
| CN103986192A (en) * | 2014-05-28 | 2014-08-13 | 阳光电源股份有限公司 | Non-isolation type photovoltaic grid-connected inverter and photovoltaic grid-connected power generation system |
| CN104065285A (en) * | 2014-03-31 | 2014-09-24 | 华为技术有限公司 | Grid-connected inverter system |
| CN104242811A (en) * | 2014-09-24 | 2014-12-24 | 彭书芳 | Photovoltaic power supply system |
| CN104242349A (en) * | 2014-10-10 | 2014-12-24 | 阳光电源股份有限公司 | Photovoltaic system with potential induced degradation prevention function and photovoltaic inverter |
| CN104426475A (en) * | 2013-08-28 | 2015-03-18 | 晶科能源有限公司 | Photovoltaic assembly and photovoltaic power station system |
| CN104506130A (en) * | 2014-11-20 | 2015-04-08 | 晶澳(扬州)太阳能光伏工程有限公司 | PID resistant device for solar photovoltaic component using non-isolated inverter |
| CN104617873A (en) * | 2015-02-02 | 2015-05-13 | 北京格林科电技术有限公司 | Method and device for suppressing potential induced degradation (PID) phenomenon of photovoltaic module through inverter |
| WO2015169135A1 (en) * | 2014-05-09 | 2015-11-12 | 阳光电源股份有限公司 | Anti-potential induced degradation photovoltaic power generation system, photovoltaic assembly and inverter |
| CN106899036A (en) * | 2017-03-16 | 2017-06-27 | 特变电工西安电气科技有限公司 | A kind of photovoltaic generating system of anti-potential induction attenuation |
| EP3364514A1 (en) * | 2017-02-15 | 2018-08-22 | Omron Corporation | Power supply system, dc/dc converter, and power conditioner |
| CN109450367A (en) * | 2019-01-15 | 2019-03-08 | 宁波锦浪新能源科技股份有限公司 | The method and apparatus inhibited for photovoltaic panel PID effect in photovoltaic plant |
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Cited By (22)
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| CN104426475A (en) * | 2013-08-28 | 2015-03-18 | 晶科能源有限公司 | Photovoltaic assembly and photovoltaic power station system |
| CN103490402A (en) * | 2013-09-05 | 2014-01-01 | 南京南瑞继保电气有限公司 | Photovoltaic module grounding device, photovoltaic module grounding monitoring device and monitoring method |
| CN103475208A (en) * | 2013-09-18 | 2013-12-25 | 江苏兆伏新能源有限公司 | PID suppression circuit of photovoltaic system |
| CN103607172A (en) * | 2013-12-05 | 2014-02-26 | 无锡上能新能源有限公司 | Device for simultaneously realizing negative grounding and ground insulation resistance detection in photovoltaic power station |
| CN103607172B (en) * | 2013-12-05 | 2017-01-04 | 上能电气股份有限公司 | Realize photovoltaic plant minus earth and the device of ground insulation resistance detection simultaneously |
| CN103647504B (en) * | 2013-12-17 | 2015-09-23 | 刘继茂 | Solar cell earthing device and method |
| CN103647504A (en) * | 2013-12-17 | 2014-03-19 | 刘继茂 | Solar cell grounding device and method |
| CN103701150A (en) * | 2013-12-26 | 2014-04-02 | 华为技术有限公司 | Multi-unit parallel circuit, power supply system and voltage regulation method |
| CN103701150B (en) * | 2013-12-26 | 2016-06-29 | 华为技术有限公司 | A kind of multi-machine parallel connection circuit, electric power system and voltage adjusting method |
| CN104065285A (en) * | 2014-03-31 | 2014-09-24 | 华为技术有限公司 | Grid-connected inverter system |
| WO2015169135A1 (en) * | 2014-05-09 | 2015-11-12 | 阳光电源股份有限公司 | Anti-potential induced degradation photovoltaic power generation system, photovoltaic assembly and inverter |
| CN103986192A (en) * | 2014-05-28 | 2014-08-13 | 阳光电源股份有限公司 | Non-isolation type photovoltaic grid-connected inverter and photovoltaic grid-connected power generation system |
| CN103986192B (en) * | 2014-05-28 | 2016-05-25 | 阳光电源股份有限公司 | A kind of non-isolated photovoltaic grid-connected inverter and grid-connected photovoltaic system |
| CN104242811A (en) * | 2014-09-24 | 2014-12-24 | 彭书芳 | Photovoltaic power supply system |
| CN104242349A (en) * | 2014-10-10 | 2014-12-24 | 阳光电源股份有限公司 | Photovoltaic system with potential induced degradation prevention function and photovoltaic inverter |
| CN104506130A (en) * | 2014-11-20 | 2015-04-08 | 晶澳(扬州)太阳能光伏工程有限公司 | PID resistant device for solar photovoltaic component using non-isolated inverter |
| CN104617873A (en) * | 2015-02-02 | 2015-05-13 | 北京格林科电技术有限公司 | Method and device for suppressing potential induced degradation (PID) phenomenon of photovoltaic module through inverter |
| EP3364514A1 (en) * | 2017-02-15 | 2018-08-22 | Omron Corporation | Power supply system, dc/dc converter, and power conditioner |
| US10461645B2 (en) | 2017-02-15 | 2019-10-29 | Omron Corporation | Power supply system, DC/DC converter, and power conditioner for suppressing performance degradation in solar cells |
| CN106899036A (en) * | 2017-03-16 | 2017-06-27 | 特变电工西安电气科技有限公司 | A kind of photovoltaic generating system of anti-potential induction attenuation |
| CN106899036B (en) * | 2017-03-16 | 2024-03-12 | 特变电工西安电气科技有限公司 | Photovoltaic power generation system capable of preventing potential induced attenuation |
| CN109450367A (en) * | 2019-01-15 | 2019-03-08 | 宁波锦浪新能源科技股份有限公司 | The method and apparatus inhibited for photovoltaic panel PID effect in photovoltaic plant |
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Application publication date: 20130814 |