CN105406516B - Anti- PID devices, anti-PID grid-connected photovoltaic systems and anti-PID approach - Google Patents
Anti- PID devices, anti-PID grid-connected photovoltaic systems and anti-PID approach Download PDFInfo
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- CN105406516B CN105406516B CN201511032028.4A CN201511032028A CN105406516B CN 105406516 B CN105406516 B CN 105406516B CN 201511032028 A CN201511032028 A CN 201511032028A CN 105406516 B CN105406516 B CN 105406516B
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- 238000013459 approach Methods 0.000 title claims abstract description 16
- 230000007935 neutral effect Effects 0.000 claims abstract description 38
- 230000005540 biological transmission Effects 0.000 claims abstract description 5
- 238000010248 power generation Methods 0.000 claims description 7
- 238000004891 communication Methods 0.000 claims description 6
- 230000005611 electricity Effects 0.000 claims description 3
- 238000002955 isolation Methods 0.000 claims 2
- 230000000694 effects Effects 0.000 abstract description 17
- 238000000034 method Methods 0.000 description 7
- 238000005516 engineering process Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 230000015556 catabolic process Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
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Classifications
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- H02J3/383—
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/12—Circuit arrangements for ac mains or ac distribution networks for adjusting voltage in ac networks by changing a characteristic of the network load
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/001—Methods to deal with contingencies, e.g. abnormalities, faults or failures
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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
Abstract
This application discloses anti-PID devices, anti-PID grid-connected photovoltaic systems and anti-PID approach, which is applied to the earth-free grid-connected photovoltaic system of DC side, including data acquisition facility, variable voltage source and equivalent circuit, wherein：The data acquisition facility, the negative busbar voltage-to-ground for obtaining the photovoltaic DC-to-AC converter that each is in grid-connected state；The equivalent circuit, the equivalent neutral point for constructing the grid-connected photovoltaic system；The electric energy output end of the variable voltage source connects the equivalent neutral point that the equivalent circuit constructs；The variable voltage source, for selecting negative busbar voltage-to-ground minimum from the data acquisition facility data that transmission comes in real time, it is lifted itself output voltage over the ground when the negative busbar voltage-to-ground minimum is negative value, until the negative busbar voltage-to-ground minimum selected reaches nonnegative value.Based on this, the application prevents photovoltaic battery panel to generate PID effects.
Description
Technical field
The present invention relates to technical field of photovoltaic power generation, more specifically to anti-PID devices, anti-PID parallel network power generations
System and anti-PID approach.
Background technology
PID (potential Induced Degradation, potential induction attenuation) effect refers to because of high pressure over the ground
The phenomenon that being applied on photovoltaic battery panel and making its reduced performance.Traditional anti-PID schemes mainly have following two：
One, it is improved by material to photovoltaic battery panel and technique to reach anti-PID effects.A but photovoltaic
Often there are numerous a photovoltaic battery panels, if carrying out material to each photovoltaic battery panel and technique changes in grid-connected system
If, then cost is too high；
Two, by configuring an anti-PID device for each photovoltaic DC-to-AC converter in a grid-connected photovoltaic system, come
Each photovoltaic battery panel for being connected to each photovoltaic DC-to-AC converter DC side is avoided to generate PID effects, still, a parallel network power generation system
Often if there are multiple photovoltaic DC-to-AC converters to be equally existed into if configuring anti-PID devices to each photovoltaic DC-to-AC converter in system
The problem of Ben Taigao.
Therefore, how to prevent photovoltaic battery panel from generating PID effects, it has also become photovoltaic industry urgent problem to be solved.
Invention content
In view of this, the present invention provides anti-PID devices, anti-PID grid-connected photovoltaic systems and anti-PID approach, to prevent
Only photovoltaic battery panel generates PID effects.
A kind of anti-PID devices are applied to the earth-free grid-connected photovoltaic system of DC side, the parallel network power generation system
System includes N number of photovoltaic battery panel, the earth-free photovoltaic DC-to-AC converter of N number of DC side and 1 isolating transformer, wherein：N number of light
Volt solar panel works independently of one another；Each described photovoltaic battery panel respectively accesses the DC side of a photovoltaic DC-to-AC converter；
The exchange side parallel connection of N number of photovoltaic DC-to-AC converter accesses the primary side of the isolating transformer, the isolating transformer it is secondary
Power grid is accessed in side；N≥1；
The anti-PID devices include data acquisition facility, variable voltage source and equivalent circuit, wherein：
The data acquisition facility, the negative mother for obtaining the photovoltaic DC-to-AC converter that each is in grid-connected state
Line-to-earth voltage；
The equivalent circuit, the equivalent neutral point for constructing the grid-connected photovoltaic system；
The communication signal output of the data acquisition facility terminates the communication signal input terminal of the variable voltage source, described
The electric energy output end of variable voltage source connects the equivalent neutral point that the equivalent circuit constructs；
The variable voltage source, for selecting negative busbar over the ground from the data acquisition facility data that transmission comes in real time
Voltage minimum is lifted itself output voltage over the ground when the negative busbar voltage-to-ground minimum is negative value, until select
Negative busbar voltage-to-ground minimum reaches nonnegative value.
Optionally, the variable voltage source, is additionally operable to that output voltage has been raised to upper limit value but has selected over the ground at itself
When negative busbar voltage minimum is still negative value, by itself, output voltage is maintained at the upper limit value over the ground, and sends out warning information.
Optionally, the variable voltage source, be additionally operable to it is described each be in the photovoltaic DC-to-AC converter of grid-connected state
After entering standby mode, controls entire anti-PID devices and also enter standby mode therewith.
Wherein, the equivalent circuit is resistance star-like connection structure, capacitance star-like connection structure or capacitance-resistance star-like connection knot
Structure.
A kind of anti-PID grid-connected photovoltaic systems, including the earth-free parallel network power generation of DC side as disclosed above
System, and any anti-PID devices as disclosed above.
A kind of anti-PID approach is applied to the earth-free grid-connected photovoltaic system of DC side, the parallel network power generation system
System includes N number of photovoltaic battery panel, the earth-free photovoltaic DC-to-AC converter of N number of DC side and 1 isolating transformer, wherein：N number of light
Volt solar panel works independently of one another；Each described photovoltaic battery panel respectively accesses the DC side of a photovoltaic DC-to-AC converter；
The exchange side parallel connection of N number of photovoltaic DC-to-AC converter accesses the primary side of the isolating transformer, the isolating transformer it is secondary
Power grid is accessed in side；N≥1；
The anti-PID approach includes：
The negative busbar voltage-to-ground for obtaining the photovoltaic DC-to-AC converter that each is in grid-connected state, is therefrom selected negative
Bus Voltage minimum；
The equivalent neutrality of the grid-connected photovoltaic system is lifted when the negative busbar voltage-to-ground minimum is negative value
The voltage-to-ground of point, until the negative busbar voltage-to-ground minimum selected reaches nonnegative value.
Optionally, the anti-PID approach further includes：
If the negative busbar voltage-to-ground minimum that the voltage-to-ground of the equivalent neutral point has been raised to upper limit value but has selected
It is still negative value, then the voltage-to-ground of the equivalent neutral point is maintained at the upper limit value, and send out warning information.
Optionally, the anti-PID approach further includes：
After each described photovoltaic DC-to-AC converter for being in grid-connected state enters standby mode, stop to the light
The equivalent neutral point of photovoltaic grid-connected system output voltage over the ground.
It can be seen from the above technical scheme that photovoltaic DC-to-AC converter busbar midpoint voltage-to-ground and equivalent neutral point over the ground
In the case that voltage remains approximately equal, equivalent neutral point voltage-to-ground variation will necessarily cause in photovoltaic DC-to-AC converter busbar
The variation of point voltage-to-ground；Again due to voltage clamp of the meeting by busbar midpoint with respect to negative busbar in photovoltaic inverter grid-connected operational process
It is made as certain value, therefore voltage-to-ground variation in photovoltaic DC-to-AC converter busbar midpoint will necessarily cause the change of its negative busbar voltage-to-ground again
Change；Based on this, the present invention will be in each light of grid-connected state by way of applying voltage-to-ground to equivalent neutral point
The negative busbar voltage-to-ground of volt inverter is adjusted to nonnegative value, the light that can so avoid each photovoltaic DC-to-AC converter from respectively connecting
The cathode for lying prostrate solar panel generates negative pressure to the earth, to prevent the photovoltaic battery panel to generate PID effects.
Description of the drawings
In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show below
There is attached drawing needed in technology description to be briefly described, it should be apparent that, the accompanying drawings in the following description is only this
Some embodiments of invention for those of ordinary skill in the art without creative efforts, can be with
Obtain other attached drawings according to these attached drawings.
Fig. 1 is disclosed by the embodiments of the present invention a kind of applied to the anti-of the earth-free grid-connected photovoltaic system of DC side
PID apparatus structure schematic diagrams；
Fig. 2 is a kind of equivalent circuit topological structure schematic diagram disclosed by the embodiments of the present invention；
Fig. 3 is disclosed by the embodiments of the present invention a kind of applied to the anti-of the earth-free grid-connected photovoltaic system of DC side
PID approach flow chart.
Specific implementation mode
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete
Site preparation describes, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other
Embodiment shall fall within the protection scope of the present invention.
The embodiment of the invention discloses a kind of anti-PID dresses applied to the earth-free grid-connected photovoltaic system of DC side
It sets, to prevent photovoltaic battery panel from generating PID effects, the anti-PID devices and its earth-free photovoltaic of DC side applied are simultaneously
The structure chart of net electricity generation system is (the arrow direction representation signal transmission direction identified in Fig. 1) as shown in Figure 1, wherein：
The grid-connected photovoltaic system includes photovoltaic battery panel #1~#N (N >=1), the earth-free photovoltaic inversion of DC side
Device #1~#N and 1 isolating transformer, specifically：Photovoltaic battery panel #1~#N works independently of one another；Each described photovoltaic electric
Pond plate respectively accesses the DC side of a photovoltaic DC-to-AC converter；The exchange side parallel connection access of photovoltaic battery panel #1~#N it is described every
The secondary side of primary side from transformer, the isolating transformer accesses power grid.
The anti-PID devices include data acquisition facility 100, variable voltage source 200 and equivalent circuit 300, specifically：
Data acquisition facility 100, the negative mother for obtaining the photovoltaic DC-to-AC converter that each is in grid-connected state
Line-to-earth voltage；
Equivalent circuit 300, equivalent neutral point (the equivalent neutral point for constructing the grid-connected photovoltaic system
For the electrical node fully equivalent with the practical neutral point of the grid-connected photovoltaic system)；
The communication signal input terminal of the communication signal output end access variable voltage source 200 of data acquisition facility 100, it is adjustable
The electric energy output end of voltage source 200 is connected on the equivalent neutral point；
Variable voltage source 200, it is electric over the ground for selecting negative busbar from the data that transmission comes in real time of data acquisition facility 100
Minimum is pressed, itself output voltage over the ground is lifted when the negative busbar voltage-to-ground minimum is negative value, until that selects is negative
Bus Voltage minimum reaches nonnegative value.
The present embodiment to the equivalent neutral point by applying corresponding voltage-to-ground, to prevent photovoltaic battery panel from generating
PID effects, concrete analysis are as follows：
Assuming that photovoltaic DC-to-AC converter #M is any one in photovoltaic DC-to-AC converter #1~#N, photovoltaic battery panel #M is to be connected on photovoltaic
The photovoltaic battery panel of inverter #M DC sides, then necessarily satisfying for：
1. to avoid photovoltaic battery panel #M from generating PID effects it is necessary to avoiding the cathode of photovoltaic battery panel #M to big real estate
Raw negative pressure；
2. the negative busbar of photovoltaic DC-to-AC converter #M and the cathode of photovoltaic battery panel #M are directly to be connected to one by a conducting wire
Rise, the two equipotential, thus the negative busbar voltage-to-ground of photovoltaic DC-to-AC converter #M be exactly photovoltaic battery panel #M cathode it is electric over the ground
Pressure；
3. during photovoltaic DC-to-AC converter #M is incorporated into the power networks, the voltage of the busbar midpoint of photovoltaic DC-to-AC converter #M with respect to negative busbar
The half for being clamped down on the bus voltage value for photovoltaic DC-to-AC converter #M is certain value；Based on this, when in the busbar of photovoltaic DC-to-AC converter #M
Point voltage-to-ground is lifted how many when, the negative busbar voltage-to-ground of photovoltaic DC-to-AC converter #M also can accordingly be lifted how much；
4. the equivalent neutral point pair of the busbar midpoint voltage-to-ground of photovoltaic DC-to-AC converter #M and the grid-connected photovoltaic system
Ground voltage remains approximately equal, is based on this, and how much is the equivalent neutral point voltage-to-ground lifting, the mother of photovoltaic DC-to-AC converter #M
Line midpoint voltage-to-ground also will approximate lifting how much.
According to 1. 2. it is found that it is necessary to avoid, photovoltaic DC-to-AC converter #M's is negative to avoid photovoltaic battery panel #M from generating PID effects
Bus Voltage is negative value；In conjunction with 3. it is found that during photovoltaic DC-to-AC converter #M is incorporated into the power networks, it can pass through and be lifted photovoltaic
The busbar midpoint voltage-to-ground of inverter #M come avoid photovoltaic DC-to-AC converter #M negative busbar voltage-to-ground be negative value；In conjunction with 4. may be used
Know, it can be by being lifted the equivalent neutral point voltage-to-ground to avoid the negative busbar voltage-to-ground of photovoltaic DC-to-AC converter #M be negative
Value.It can be seen that during photovoltaic DC-to-AC converter #M is incorporated into the power networks, can be kept away by adjusting the equivalent neutral point voltage-to-ground
The cathode for exempting from photovoltaic battery panel #M generates negative pressure to the earth, to avoid photovoltaic battery panel #M from generating PID effects.
In turn, it is contemplated that in photovoltaic DC-to-AC converter #1~#N, the negative busbar voltage-to-ground of different photovoltaic DC-to-AC converters is not necessarily
It is equal, therefore to ensure that photovoltaic battery panel #1~#N does not generate PID effects, just it has to be ensured that photovoltaic DC-to-AC converter #1~#N
Negative busbar voltage-to-ground in minimum must be in nonnegative value.
Conceived based on foregoing invention, the present embodiment obtains the negative of photovoltaic DC-to-AC converter #1~#N using data acquisition facility 100
Bus Voltage)；Variable voltage source 200 is applied to according to the data that data acquisition facility 100 exports to adjust itself in real time
The voltage-to-ground of the equivalent neutral point so that the minimum in the negative busbar voltage-to-ground of photovoltaic DC-to-AC converter #1~#N can
In nonnegative value, PID effects are generated to effectively prevent photovoltaic battery panel #1~#N.
Wherein it should be noted that data acquisition facility 100 only obtains the photovoltaic DC-to-AC converter in grid-connected state
Negative busbar voltage-to-ground, when in photovoltaic DC-to-AC converter #1~#N there are one or several failures and off-network or when shutting down, then data
Acquisition device 100 does not continue to obtain the negative busbar voltage-to-ground of these photovoltaic DC-to-AC converters, in case it is electric over the ground to influence negative busbar
Press the selection of minimum as a result, influencing the anti-PID effects of entire PID devices in turn.
In addition, when each photovoltaic DC-to-AC converter for being in grid-connected state enters standby mode, the present embodiment is public
The anti-PID devices held can also be transferred to standby mode therewith under the control of variable voltage source 200, stop output voltage over the ground, with
Reduce own loss.Wherein, variable voltage source 200 can voluntarily detect that it is inverse that each is in the photovoltaic of grid-connected state
Become device and into standby mode or receives instruction information that extraneous transmission comes or staff triggers Opportunity awaiting control for linear switch manually
Deng as the trigger condition for controlling anti-PID devices and entering standby mode.
In addition, it is contemplated that the busbar voltage of photovoltaic DC-to-AC converter is electric no more than the open circuit for the photovoltaic battery panel that it is connected
Pressure, therefore the output voltage over the ground of variable voltage source 200 is equipped with upper limit value, if the output voltage over the ground of variable voltage source 200 is
It is adjusted to upper limit value but the negative busbar voltage-to-ground minimum selected is still in negative value, then variable voltage source 200 is defeated over the ground by itself
Go out voltage and be maintained at the upper limit value, and sends out warning information.
Wherein, the topological structure that Fig. 2 is provided can be used in equivalent circuit 300, is resistance star-like connection structure, specially：Electricity
Hinder mono- tip node N of R1, the A phase lines of another termination grid-connected photovoltaic system；Mono- tip node N of resistance R2, another termination institute
State the B phase lines of grid-connected photovoltaic system；Mono- tip node N of resistance R3, the C phases of another termination grid-connected photovoltaic system
Line；R1=R2=R3；The common end N of three resistance R1~R3 be construct the grid-connected photovoltaic system it is equivalent in
Property point.Alternatively, capacitance star-like connection structure or capacitance-resistance star-like connection structure etc. can be used in equivalent circuit 300.
It can be seen from the above description that in photovoltaic DC-to-AC converter busbar midpoint voltage-to-ground and equivalent neutral point voltage-to-ground
In the case of remaining approximately equal, equivalent neutral point voltage-to-ground variation will necessarily cause photovoltaic DC-to-AC converter busbar midpoint pair
The variation of ground voltage；Again since voltage clamp that can be by busbar midpoint with respect to negative busbar in photovoltaic inverter grid-connected operational process is
Certain value, therefore voltage-to-ground variation in photovoltaic DC-to-AC converter busbar midpoint will necessarily cause the variation of its negative busbar voltage-to-ground again；
Based on this, each photovoltaic that the present invention will be in grid-connected state by way of applying voltage-to-ground to equivalent neutral point is inverse
The negative busbar voltage-to-ground for becoming device is adjusted to nonnegative value, the photovoltaic electric that can so avoid each photovoltaic DC-to-AC converter from respectively connecting
The cathode of pond plate generates negative pressure to the earth, to prevent the photovoltaic battery panel to generate PID effects.
In addition, the embodiment of the invention also discloses a kind of anti-PID grid-connected photovoltaic systems, including it is as disclosed above straight
Flow the earth-free grid-connected photovoltaic system in side, and any anti-PID devices as disclosed above.
In addition, referring to Fig. 3, the embodiment of the invention also discloses a kind of anti-PID approaches, are applied to direct current as disclosed above
The earth-free grid-connected photovoltaic system in side, this method include：
Step 301：The negative busbar voltage-to-ground for obtaining the photovoltaic DC-to-AC converter that each is in grid-connected state, from
In select negative busbar voltage-to-ground minimum；
Step 302：It is lifted the grid-connected photovoltaic system when the negative busbar voltage-to-ground minimum is negative value
The voltage-to-ground of equivalent neutral point, until the negative busbar voltage-to-ground minimum selected reaches nonnegative value.
Optionally, it in step 302 implementation procedure, to upper limit value but is selected if the voltage of the equivalent neutral point is modulated
Negative busbar voltage-to-ground minimum is still negative value, then the voltage-to-ground of the equivalent neutral point is maintained at the upper limit value, and
Send out warning information.
Optionally, the anti-PID approach further includes：It is described each be in the photovoltaic DC-to-AC converter of grid-connected state into
After entering standby mode, stop to equivalent neutral point output voltage over the ground.
In conclusion remaining approximate with equivalent neutral point voltage-to-ground in photovoltaic DC-to-AC converter busbar midpoint voltage-to-ground
In the case of equal, equivalent neutral point voltage-to-ground variation will necessarily cause the change of photovoltaic DC-to-AC converter busbar midpoint voltage-to-ground
Change；Again due to that can be certain value by the voltage clamp of the opposite negative busbar in busbar midpoint in photovoltaic inverter grid-connected operational process, because
This photovoltaic DC-to-AC converter busbar midpoint voltage-to-ground variation will necessarily cause the variation of its negative busbar voltage-to-ground again；Based on this, originally
Invention will be in the negative of each photovoltaic DC-to-AC converter of grid-connected state by way of applying voltage-to-ground to equivalent neutral point
Bus Voltage is adjusted to nonnegative value, can so avoid the negative of the photovoltaic battery panel that each photovoltaic DC-to-AC converter respectively connects
Negative pressure extremely is generated to the earth, to prevent the photovoltaic battery panel to generate PID effects.
Each embodiment is described by the way of progressive in this specification, the highlights of each of the examples are with other
The difference of embodiment, just to refer each other for identical similar portion between each embodiment.For anti-PID disclosed in embodiment
For grid-connected photovoltaic system and anti-PID approach, since it is corresponding with device disclosed in embodiment, so the comparison of description
Simply, related place illustrates referring to device part.
The foregoing description of the disclosed embodiments enables those skilled in the art to implement or use the present invention.
Various modifications to these embodiments will be apparent to those skilled in the art, as defined herein
General Principle can in other embodiments be realized in the case where not departing from the spirit or scope of the embodiment of the present invention.Therefore,
The embodiment of the present invention is not intended to be limited to the embodiments shown herein, and be to fit to principles disclosed herein and
The consistent widest range of features of novelty.
Claims (6)
1. a kind of anti-PID devices, which is characterized in that be applied to the earth-free grid-connected photovoltaic system of DC side, the photovoltaic
Grid-connected system includes N number of photovoltaic battery panel, the earth-free photovoltaic DC-to-AC converter of N number of DC side and 1 isolating transformer,
In：N number of photovoltaic battery panel works independently of one another；Each described photovoltaic battery panel respectively accesses a photovoltaic inversion
The DC side of device；The exchange side parallel connection of N number of photovoltaic DC-to-AC converter accesses the primary side of the isolating transformer, and the isolation becomes
The secondary side of depressor accesses power grid；N≥1；
The anti-PID devices include data acquisition facility, variable voltage source and equivalent circuit, wherein：
The data acquisition facility, the negative busbar pair for obtaining the photovoltaic DC-to-AC converter that each is in grid-connected state
Ground voltage, when in the photovoltaic DC-to-AC converter there are one or several photovoltaic DC-to-AC converters break down and off-network or shut down when, the number
The negative busbar voltage-to-ground of the photovoltaic DC-to-AC converter of off-network or shutdown is not continued to obtain according to acquisition device；
The equivalent circuit, the equivalent neutral point for constructing the grid-connected photovoltaic system；The equivalent circuit be by
The points of common connection of the star-like connection structure that the equal resistance of three resistance values is constituted, these three resistance is the parallel network power generation
The equivalent neutral point of system；
The communication signal output of the data acquisition facility terminates the communication signal input terminal of the variable voltage source, described adjustable
The electric energy output end of voltage source connects the equivalent neutral point that the equivalent circuit constructs；
The variable voltage source, for selecting negative busbar voltage-to-ground from the data acquisition facility data that transmission comes in real time
Minimum is lifted itself output voltage over the ground when the negative busbar voltage-to-ground minimum is negative value, until the negative mother selected
Line-to-earth voltage minimum reaches nonnegative value；
The variable voltage source, be additionally operable to itself over the ground output voltage be raised to upper limit value but the negative busbar voltage selected most
When low value is still negative value, by itself, output voltage is maintained at the upper limit value over the ground, and sends out warning information.
2. anti-PID devices according to claim 1, which is characterized in that the variable voltage source is additionally operable to described each
After a photovoltaic DC-to-AC converter in grid-connected state enters standby mode, the entire anti-PID devices of control also enter therewith to be waited for
Machine state.
3. anti-PID devices according to claim 1, which is characterized in that the equivalent circuit be resistance star-like connection structure,
Capacitance star-like connection structure or capacitance-resistance star-like connection structure.
4. a kind of anti-PID grid-connected photovoltaic systems, which is characterized in that earth-free including DC side as described in claim 1
Grid-connected photovoltaic system and anti-PID devices as claimed in any one of claims 1-3.
5. a kind of anti-PID approach, which is characterized in that be applied to the earth-free grid-connected photovoltaic system of DC side, the photovoltaic
Grid-connected system includes N number of photovoltaic battery panel, the earth-free photovoltaic DC-to-AC converter of N number of DC side and 1 isolating transformer,
In：N number of photovoltaic battery panel works independently of one another；Each described photovoltaic battery panel respectively accesses a photovoltaic inversion
The DC side of device；The exchange side parallel connection of N number of photovoltaic DC-to-AC converter accesses the primary side of the isolating transformer, and the isolation becomes
The secondary side of depressor accesses power grid；N≥1；
The anti-PID approach includes：
The negative busbar voltage-to-ground for obtaining the photovoltaic DC-to-AC converter that each is in grid-connected state, therefrom selects negative busbar
Voltage-to-ground minimum, when in the photovoltaic DC-to-AC converter there are one or several photovoltaic DC-to-AC converters break down and off-network or shutdown
When, data acquisition facility does not continue to obtain the negative busbar voltage-to-ground of the photovoltaic DC-to-AC converter of off-network or shutdown；
The equivalent neutral point of the grid-connected photovoltaic system is lifted when the negative busbar voltage-to-ground minimum is negative value
Voltage-to-ground, until the negative busbar voltage-to-ground minimum selected reaches nonnegative value；It is constituted using the equal resistance of three resistance values
The points of common connection of star-like connection structure, these three resistance is the equivalent neutral point of the grid-connected photovoltaic system；
If the voltage-to-ground of the equivalent neutral point has been raised to upper limit value but the negative busbar voltage-to-ground minimum selected still is
The voltage-to-ground of the equivalent neutral point is then maintained at the upper limit value, and sends out warning information by negative value.
6. anti-PID approach according to claim 5, which is characterized in that further include：
After each described photovoltaic DC-to-AC converter for being in grid-connected state enters standby mode, stop to the photovoltaic simultaneously
The equivalent neutral point of net electricity generation system output voltage over the ground.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201511032028.4A CN105406516B (en) | 2015-12-30 | 2015-12-30 | Anti- PID devices, anti-PID grid-connected photovoltaic systems and anti-PID approach |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201511032028.4A CN105406516B (en) | 2015-12-30 | 2015-12-30 | Anti- PID devices, anti-PID grid-connected photovoltaic systems and anti-PID approach |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105406516A CN105406516A (en) | 2016-03-16 |
| CN105406516B true CN105406516B (en) | 2018-10-02 |
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| CN106786750B (en) * | 2016-12-27 | 2019-08-13 | 阳光电源股份有限公司 | Photovoltaic parallel in system and photovoltaic combining inverter |
| 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 |
| CN111262429B (en) * | 2020-03-17 | 2021-06-11 | 阳光电源股份有限公司 | Direct current conversion circuit and photovoltaic inverter |
| CN116235380A (en) * | 2020-12-31 | 2023-06-06 | 华为数字能源技术有限公司 | Photovoltaic system, power supply system and control method |
| CN116207789B (en) * | 2023-05-06 | 2023-07-21 | 锦浪科技股份有限公司 | PID effect suppression method based on zero sequence |
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| CN203166494U (en) * | 2013-03-26 | 2013-08-28 | 阳光电源（上海）有限公司 | Device for solving potential induced degradation |
| CN103973217A (en) * | 2014-05-19 | 2014-08-06 | 无锡上能新能源有限公司 | Device for restraining PID effect of photovoltaic panel |
| CN104065285A (en) * | 2014-03-31 | 2014-09-24 | 华为技术有限公司 | Grid-connected inverter system |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203166494U (en) * | 2013-03-26 | 2013-08-28 | 阳光电源（上海）有限公司 | Device for solving potential induced degradation |
| CN104065285A (en) * | 2014-03-31 | 2014-09-24 | 华为技术有限公司 | Grid-connected inverter system |
| CN103973217A (en) * | 2014-05-19 | 2014-08-06 | 无锡上能新能源有限公司 | Device for restraining PID effect of photovoltaic panel |
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