CN113922652B - Inverter, inverter system, lightning protection circuit and control method of lightning protection circuit - Google Patents
Inverter, inverter system, lightning protection circuit and control method of lightning protection circuit Download PDFInfo
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- CN113922652B CN113922652B CN202111362707.3A CN202111362707A CN113922652B CN 113922652 B CN113922652 B CN 113922652B CN 202111362707 A CN202111362707 A CN 202111362707A CN 113922652 B CN113922652 B CN 113922652B
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- 230000001276 controlling effect Effects 0.000 claims description 4
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- 239000003990 capacitor Substances 0.000 description 2
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- 208000025274 Lightning injury Diseases 0.000 description 1
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/32—Means for protecting converters other than automatic disconnection
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
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Abstract
The application discloses an inverter, an inverter system, a lightning protection circuit and a control method thereof. The connection point of the first lightning protection module and the second lightning protection module is connected with the middle point of the voltage equalizing circuit between two poles of the line to be protected, so that the voltage division of the first lightning protection module is equal to the voltage division of the second lightning protection module, and the lightning protection circuit can ensure that each lightning protection module uniformly bears the voltage between two poles of the line to be protected; therefore, the voltage division of each lightning protection module does not exceed half of the voltage of the two poles of the line to be protected, namely, the voltage does not exceed the safety voltage of the inverter when the inverter works at rated voltage; therefore, the lightning protection circuit provided by the application can avoid being damaged when the circuit to be protected works normally; and when the circuit to be protected is a direct current bus of the inverter, the lightning protection circuit can avoid being damaged when the inverter works normally.
Description
Technical Field
The invention relates to the technical field of power electronics, in particular to an inverter, an inverter system, a lightning protection circuit and a control method of the lightning protection circuit.
Background
Generally, a lightning protection circuit is arranged between two poles of a direct current bus of the inverter so as to avoid damage to the inverter caused by lightning stroke; when the inverter is in the floating system, the voltage born by two lightning protection modules connected in series between the direct current buses in the lightning protection circuit is half of the bus voltage.
However, at present, when the dc side negative electrode of the inverter is grounded or the inverter is operated in the PID inhibition mode, the voltage born by the individual lightning protection circuit may exceed half of the bus voltage, that is, the safety voltage of the individual lightning protection circuit may be exceeded when the inverter is operated at the rated voltage, so that the lightning protection circuit may be damaged when the inverter is operated normally.
Therefore, how to avoid the lightning protection circuit from being damaged during normal operation of the inverter is a technical problem to be solved.
Disclosure of Invention
In view of the above, the present invention provides an inverter, an inverter system, a lightning protection circuit and a control method thereof, so as to avoid the lightning protection circuit from being damaged during normal operation of the inverter.
In order to achieve the above object, the embodiment of the present invention provides the following technical solutions:
a first aspect of the present application provides a lightning protection circuit comprising: the first lightning protection module, the second lightning protection module and the third lightning protection module; wherein:
the first lightning protection module and the second lightning protection module are connected in series between two poles of a circuit to be protected;
the connection point of the first lightning protection module and the second lightning protection module is grounded through the third lightning protection module;
and the connection point of the first lightning protection module and the second lightning protection module is connected with the midpoint of the voltage equalizing circuit between the two poles of the line to be protected.
Optionally, when the voltage equalizing circuit is not arranged between two poles of the line to be protected, or the resistance value of the voltage equalizing circuit is greater than a preset resistance value, two ends of the third lightning protection module are connected with the output end of the voltage applying module to replace the connection between the connection point of the first lightning protection module and the second lightning protection module and the midpoint of the voltage equalizing circuit;
the voltage application module is used for outputting the regulating voltage when the partial voltage of at least one lightning protection module is larger than the safety voltage of the lightning protection module, so that the partial voltages of the three lightning protection modules are smaller than the respective safety voltages.
Optionally, the voltage applying module takes electricity from the line to be protected;
the voltage applying module is a direct current-direct current conversion module.
Optionally, when the line to be protected is a dc bus in an inverter, the voltage applying module takes power from an ac branch in the inverter;
the voltage application module is an alternating current-direct current conversion module.
Optionally, the method further comprises: two fusing modules; wherein:
the two ends of a serial branch formed by the first lightning protection module and the second lightning protection module are respectively connected with the two poles of the circuit to be protected through one fusing module.
Optionally, the circuit to be protected includes: a direct current bus in an inverter, or a direct current bus in a junction box of a front stage of the inverter.
A second aspect of the present application provides a control method of a lightning protection circuit, applied to the lightning protection circuit as described in any one of the first aspect of the present application when the first aspect includes a voltage application module; the control method of the lightning protection circuit comprises the following steps:
determining the partial pressure of each lightning protection module in the lightning protection circuit;
judging whether the partial voltage of at least one lightning protection module in the lightning protection circuit is larger than the self safety voltage or not;
if at least one lightning protection module in the lightning protection circuit has the partial pressure larger than the self safety voltage, controlling a voltage application module in the lightning protection circuit to output the regulating voltage, enabling the partial pressures of the three lightning protection modules to be smaller than the respective safety voltage, and returning to execute the step of determining the partial pressure of each lightning protection module in the lightning protection circuit.
Optionally, determining the partial pressure of each lightning protection module in the lightning protection circuit includes:
and calculating the partial pressure of each lightning protection module by utilizing the partial pressure relation of each lightning protection module and combining the two-pole voltage of the line to be protected.
Optionally, before determining the voltage division of each lightning protection module in the lightning protection circuit, the method further includes:
judging whether the difference between the negative electrode potential of the circuit to be protected and the ground level is smaller than or equal to the preset difference value;
and if the difference between the negative electrode potential of the circuit to be protected and the ground level is smaller than or equal to the preset difference value, executing the step of determining the partial pressure of each lightning protection module in the lightning protection circuit.
Optionally, when the line to be protected is a dc bus of an inverter, or the line to be protected is directly connected to the dc bus of the inverter, determining whether a difference between a negative potential of the line to be protected and a ground level is less than or equal to the preset difference value includes:
judging whether the negative electrode of the inverter is grounded or not, or whether the inverter works in a PID suppression mode or not;
and if the negative electrode of the inverter is grounded or the inverter works in the PID suppression module, judging that the difference between the negative electrode potential of the circuit to be protected and the ground level is smaller than or equal to the preset difference value.
Optionally, when the line to be protected is not a dc bus of an inverter and the line to be protected is not directly connected to the dc bus of the inverter, determining whether a difference between a negative potential of the line to be protected and a ground level is smaller than the preset difference includes:
judging whether the negative electrode of the circuit to be protected is grounded or not;
and if the negative electrode of the circuit to be protected is grounded, judging that the difference between the potential of the negative electrode of the circuit to be protected and the ground level is smaller than or equal to the preset difference value.
A third aspect of the present application provides an inverter, including: an inverter module, a direct current bus, an alternating current branch and a lightning protection circuit according to any one of the first aspects of the present application; wherein:
the direct current side of the inversion module is connected with the output of the front stage through the direct current bus, and the alternating current side of the inversion module is connected with the alternating current branch;
the lightning protection circuit is arranged between two poles of the direct current bus.
A fourth aspect of the present application provides an inverter system, including: at least one combiner box and an inverter as described in the third aspect of the present application; wherein:
the output end of the combiner box is connected with the direct current side of the inverter.
Optionally, a lightning protection circuit according to any one of claims 1-6 is arranged between two poles of a direct current bus in the combiner box.
According to the technical scheme, the invention provides a lightning protection circuit, which specifically comprises: the first lightning protection module, the second lightning protection module and the third lightning protection module. The connection point of the first lightning protection module and the second lightning protection module is connected with the middle point of the voltage equalizing circuit between two poles of the line to be protected, so that the voltage division of the first lightning protection module is equal to the voltage division of the second lightning protection module, and the lightning protection circuit can ensure that each lightning protection module uniformly bears the voltage between two poles of the line to be protected; therefore, the voltage division of each lightning protection module does not exceed half of the voltage of the two poles of the line to be protected, namely, the voltage does not exceed the safety voltage of the inverter when the inverter works at rated voltage; therefore, the lightning protection circuit provided by the application can avoid being damaged when the circuit to be protected works normally; and when the circuit to be protected is a direct current bus of the inverter, the lightning protection circuit can avoid being damaged when the inverter works normally.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only embodiments of the present invention, and that other drawings can be obtained according to the provided drawings without inventive effort for a person skilled in the art.
Fig. 1 to fig. 6 are schematic diagrams of six structures of an inverter with a lightning protection circuit according to an embodiment of the present application;
fig. 7 to fig. 10 are respectively four flow diagrams of a control method of a lightning protection circuit according to an embodiment of the present application;
fig. 11 is a schematic structural diagram of a photovoltaic system for use in embodiments of the present application.
Detailed Description
The following description of the embodiments of the present application will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all, of the embodiments of the present application. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments herein without making any inventive effort, are intended to be within the scope of the present application.
In this application, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.
In order to avoid the lightning protection circuit being damaged during normal operation of the inverter, the embodiment of the present application provides a lightning protection circuit, the specific structure of which can be seen at 10 in fig. 1, which specifically includes: the first lightning protection module MOV1, the second lightning protection module MOV2 and the third lightning protection module MOV3.
In the lightning protection circuit, a first lightning protection module MOV1 and a second lightning protection module MOV2 are connected in series between two poles of a line to be protected, such as a dc bus 40 in the inverter in fig. 1; the connection point N2 of the first lightning protection module MOV1 and the second lightning protection module MOV2 is grounded PE through the third lightning protection module MOV 3; further, as shown in fig. 1, the connection point N2 of the first lightning protection module MOV1 and the second lightning protection module MOV2 is connected to the midpoint N3 of the voltage equalizing circuit 21 between the two poles of the line to be protected.
In general, a capacitor branch is further disposed between two poles of the line to be protected, and a midpoint N1 of the capacitor branch is taken as a midpoint of the line to be protected and is connected to a midpoint N3 of the voltage-sharing circuit 21, so that a connection point N2 of the first lightning protection module MOV1 and the second lightning protection module MOV2 is connected to a midpoint N3 of the voltage-sharing circuit 21 between two poles of the line to be protected, which may also be equivalent to: is connected with the midpoint N1 of the line to be protected.
It should be noted that, when the line to be protected is the dc bus 40 in the inverter, it is also required that the midpoint N3 of the voltage equalizing circuit 21 must be connected to the midpoint of the inverter module 20, as shown in fig. 1.
The voltage division of the first lightning protection module MOV1 is equal to the voltage division of the second lightning protection module MOV2 because the connection point of the first lightning protection module MOV1 and the second lightning protection module MOV2 is connected with the middle point of the voltage equalizing circuit between two poles of the line to be protected, so that the lightning protection circuit can ensure that each lightning protection module in the lightning protection circuit uniformly bears the voltage between two poles of the line to be protected; therefore, the voltage division of each lightning protection module does not exceed half of the voltage of the two poles of the line to be protected, namely, the voltage does not exceed the safety voltage of the inverter when the inverter works at rated voltage; therefore, the lightning protection circuit provided by the application can avoid being damaged when the circuit to be protected works normally; and when the circuit to be protected is a direct current bus of the inverter, the lightning protection circuit can avoid being damaged when the inverter works normally.
It is worth to say that, this application is on the lightning protection module basis that does not select higher voltage class, alright avoid lightning protection circuit to be damaged when waiting to protect the normal work of circuit, consequently, this lightning protection circuit still can reduce the residual voltage of device port when the thunderbolt protection to simplify the protection design of back-stage circuit.
In another embodiment of the present application, referring to fig. 2 and 3, when the voltage equalizing circuit 21 is not disposed between two poles of the line to be protected, or the resistance of the voltage equalizing circuit 21 is greater than the preset resistance, two ends of the third lightning protection module MOV3 in the lightning protection circuit are connected to the output end of the voltage applying module 11, instead of the connection between the connection point of the first lightning protection module MOV1 and the second lightning protection module MOV2 and the midpoint N3 of the voltage equalizing circuit 21.
When the resistance of the voltage-sharing circuit 21 is greater than the preset resistance, if the connection point N2 of the first lightning protection module MOV1 and the second lightning protection module MOV2 is still connected to the midpoint N3 of the voltage-sharing circuit 21, the potential of the midpoint N3 of the voltage-sharing circuit 21 and the midpoint N1 of the circuit to be protected deviate, that is, the partial voltages of the three lightning protection modules cannot be ensured to be smaller than the respective safety voltages, so that the lightning protection circuit cannot be prevented from being damaged when the circuit to be protected is normal; in practical applications, the preset resistance is usually set to tens of kiloohms or hundreds of kiloohms.
In operation, the voltage application module 11 outputs the regulated voltage when the voltage division of at least one lightning protection module is greater than the self-safety voltage, so that the voltage division of the three lightning protection modules is smaller than or equal to the respective safety voltage.
Preferably, an adjusting voltage which is more than or equal to half of the voltage of the two poles of the bus to be protected and less than or equal to half of the rated voltage of the bus to be protected is output; in practical applications, including but not limited to the above embodiments, the present invention is not limited to the above embodiments, and may be applied to the protection scope of the present application as the case may be.
According to the scheme, the voltage division of the three lightning protection modules is maintained below the respective safety voltage through voltage regulation, so that even if the circuit to be protected normally works at the rated voltage at this time, the voltage division of the three lightning protection modules is smaller than or equal to the respective safety voltage, and the lightning protection circuit can ensure that the three lightning protection modules are not damaged when the circuit to be protected normally works.
In this embodiment, the voltage application module 11 may take power from the line to be protected, for example, as shown in fig. 2, from the dc bus 40 in the inverter; when the line to be protected is the dc bus 40 in the inverter, as shown in fig. 3, the voltage application module 11 may also take power from the ac branch 30 in the inverter, which is not specifically limited herein, and may be within the protection scope of the present application according to the specific situation.
It should be noted that, a specific way of taking power from the ac branch 30 in the inverter may be taking power from the secondary side of the transformer Grid in the ac branch 30, as shown in fig. 3; power may also be taken from the primary side of the transformer Grid in the ac branch 30; the power can be taken from the front or the rear of the alternating current inductor L; in practical applications, including but not limited to the above embodiments, the present invention is not limited to the above embodiments, and may be applied to the protection scope of the present application as the case may be.
Specifically, when the voltage application module 11 takes electricity from the line to be protected, the voltage application module 11 is a dc-dc conversion module; when the voltage application module 11 takes power from the ac branch 30, the voltage application module 11 is an ac-dc conversion module.
In another embodiment of the present application, the voltage application module 11 determines the voltage division of the three lightning protection modules according to the voltage division relationship between the two-pole voltage of the line to be protected and the three lightning protection modules.
Specifically, when the voltage application module 11 does not output the regulated voltage, the voltage application module 11 calculates the partial voltage of the three lightning protection modules by using the resistance ratio of the three lightning protection modules and combining the two-pole voltage of the line to be protected; after the voltage application module 11 outputs the regulated voltage, the voltage application module 11 calculates the partial voltages of the three lightning protection modules by using the relationship that the voltage of the two poles of the line to be protected is equal to the sum of the partial voltage of the first lightning protection module MOV1 and the partial voltage of the third lightning protection module MOV3 and the relationship that the partial voltage of the second lightning protection module MOV2 and the partial voltage of the third lightning protection module MOV3 are equal, and combining the voltage of the two poles of the line to be protected.
The voltage application module 11 obtains the voltage of two poles of the circuit to be protected through a voltage sampling unit in the device where the lightning protection circuit is located.
It should be noted that, the partial pressure relationship of the three lightning protection modules is related to the respective properties, that is, after the lightning protection modules are selected, the partial pressure relationship of the three lightning protection modules can be determined.
The foregoing provides only one preferred embodiment for determining the partial pressure of three lightning protection modules, and in practical applications, including but not limited to this preferred embodiment, is not specifically limited herein, and may be within the scope of the present application as the case may be.
In another embodiment of the present application, referring to fig. 4 to fig. 6, on the basis of any one of the above embodiments, the lightning protection module further includes: two fuse modules 12; wherein, two ends of a serial branch formed by the first lightning protection module MOV1 and the second lightning protection module MOV2 are respectively connected with two poles of a line to be protected through a fusing module 12, such as a direct current bus 40 in an inverter in fig. 4-6; the method comprises the steps of carrying out a first treatment on the surface of the When the lightning protection module fails and a short circuit occurs, the two fusing modules 12 fuse to avoid the short circuit of the positive electrode and the negative electrode of the circuit to be protected.
In this embodiment, the fusing module 12 is preferably a fuse, and in practical applications, including but not limited to this preferred embodiment, the present invention is not limited thereto, and it is within the scope of the present application as the case may be.
Alternatively, the line to be protected may be a dc bus 40 in an inverter, as shown in fig. 1; the dc bus 400 in the junction box of the front stage of the inverter may be as shown in fig. 8; in practical applications, including but not limited to the above embodiments, the present invention is not limited to the above embodiments, and may be applied to the protection scope of the present application as the case may be.
In this embodiment, the lightning protection module is preferably a varistor, and in practical applications, including but not limited to this preferred embodiment, the lightning protection module is not specifically limited herein, and may be within the protection scope of the present application as the case may be.
Another embodiment of the present application provides a control method of a lightning protection circuit, which is applied to a lightning protection circuit including a voltage application module; the specific flow of the control method of the lightning protection circuit is shown in fig. 7, and specifically comprises the following steps:
s110, determining the partial pressure of each lightning protection module.
In another embodiment of the present application, the specific implementation manner of step S110 is:
and calculating the partial pressure of each lightning protection module by utilizing the partial pressure relation of each lightning protection module and combining the two-pole voltage of the line to be protected.
The partial pressure relations of the three lightning protection modules are related to the respective properties, namely, after the lightning protection modules are selected, the partial pressure relations of the three lightning protection modules can be determined; the voltage of two poles of the line to be protected is obtained by a voltage sampling unit in the device where the lightning protection circuit is located.
It should be noted that, the step of calculating the partial pressure of each lightning protection module is described in detail in the above embodiments, which is not described here again.
The foregoing provides only one preferred embodiment for determining the partial pressure of three lightning protection modules, and in practical applications, including but not limited to this preferred embodiment, is not specifically limited herein, and may be within the scope of the present application as the case may be.
S120, judging whether the partial voltage of at least one lightning protection module in the lightning protection circuit is larger than the safety voltage of the lightning protection module.
If it is determined that the voltage division of at least one lightning protection module in the lightning protection circuit is greater than the self safety voltage, executing step S130, and returning to execute step S110; and if the partial voltage of all the lightning protection modules in the lightning protection circuit is less than or equal to the self safety voltage, stopping executing the control method of the lightning protection circuit.
S130, controlling a voltage application module in the lightning protection circuit to output an adjusting voltage, so that the partial voltage of the three lightning protection modules is smaller than the respective safety voltage.
It should be noted that, the specific embodiments of the voltage adjustment have been described in detail in the foregoing embodiments, and are not described herein in detail.
Another embodiment of the present application provides another implementation manner of the control method of the lightning protection circuit, and the specific structure of the implementation manner is shown in fig. 8, and before step S110, the implementation manner further includes the following steps:
s210, judging whether the difference between the negative electrode potential of the circuit to be protected and the ground level is smaller than or equal to a preset difference value.
If the difference between the negative electrode potential and the ground level of the line to be protected is less than or equal to the preset difference value, executing step S110; and if the difference between the negative electrode potential of the circuit to be protected and the ground level is larger than the preset difference value, stopping executing the control method of the lightning protection circuit.
The preset difference is preset according to actual conditions, and when the line to be protected is a direct current bus of the inverter, the preset difference is usually set to 10V.
In another embodiment of the present application, as shown in fig. 9, when the line to be protected is a dc bus of an inverter, or the line to be protected is directly connected to the dc bus of the inverter, the specific implementation of step S210 includes the following steps:
s310, judging whether the negative electrode of the inverter is grounded or not, or whether the inverter works in a PID suppression mode or not.
If the negative pole of the inverter is grounded, or the inverter works in the PID suppression module, executing step S320; if the negative electrode of the inverter is not grounded and the inverter is not operating in the PID suppression module, step S330 is performed.
S320, judging that the difference between the negative electrode potential of the circuit to be protected and the ground level is smaller than or equal to a preset difference value.
S330, determining that the difference between the negative electrode potential of the line to be protected and the ground level is larger than a preset difference value.
In another embodiment of the present application, as shown in fig. 10, when the line to be protected is not a dc bus of an inverter and the line to be protected is not directly connected to the dc bus of the inverter, the specific implementation of step S210 includes the following steps:
s410, judging whether the negative electrode of the circuit to be protected is grounded.
If the negative electrode of the line to be protected is grounded, step S420 is executed; if the negative electrode of the line to be protected is not grounded, step S430 is performed.
S420, judging that the difference between the negative electrode potential of the circuit to be protected and the ground level is smaller than or equal to a preset difference value.
S430, judging that the difference between the negative electrode potential of the line to be protected and the ground level is larger than a preset difference value.
Another embodiment of the present application provides an inverter, with specific structure referring to fig. 1-6 (fig. 1 and fig. 4, where the ac branch 40 is not output), specifically including: the inverter module 20, the dc bus 40, the ac branch 30, and the lightning protection circuit 10 provided in the above embodiment.
In the inverter, the dc side of the inverter module 20 is connected to the front-stage output via a dc bus 40, and the ac side of the inverter module 20 is connected to an ac branch 30; the lightning protection circuit 10 is disposed between two poles of the dc bus 40.
It should be noted that, the setting mode and the power taking mode of the lightning protection circuit 10 have been described in detail in the above embodiments, and are not described in detail herein; the specific structure of the ac branch 30 is shown in fig. 2, 3, 5 or 6, and will not be described here again.
Another embodiment of the present application provides an inverter system, the specific structure of which can be seen in fig. 11, specifically including: at least one combiner box 200 and the inverter 100 as provided in the above-described embodiments.
In the inverter system, an output end of each combiner box 200 is connected to a direct current side of the inverter 100. It should be noted that, the setting mode and the power taking mode of the lightning protection circuit 10 are described in detail in the above embodiments, and are not described in detail here.
In another embodiment of the present application, the lightning protection circuit 10 shown in fig. 2 or 5 is provided between two poles of the dc bus 400 in the junction box.
In another embodiment of the present application, the inverter system is a photovoltaic system, as shown in fig. 11, and includes at least one photovoltaic string 300, and an output end of each photovoltaic string 300 is connected in parallel to an input end of the combiner box 200.
The features described in the various embodiments of the present disclosure may be interchanged or combined with each other in the above description of the disclosed embodiments to enable those skilled in the art to make or use the present application. The above description is only of the preferred embodiment of the present invention, and is not intended to limit the present invention in any way. While the invention has been described with reference to preferred embodiments, it is not intended to be limiting. Any person skilled in the art can make many possible variations and modifications to the technical solution of the present invention or modifications to equivalent embodiments using the methods and technical contents disclosed above, without departing from the scope of the technical solution of the present invention. Therefore, any simple modification, equivalent variation and modification of the above embodiments according to the technical substance of the present invention still fall within the scope of the technical solution of the present invention.
Claims (13)
1. A lightning protection circuit, comprising: the first lightning protection module, the second lightning protection module and the third lightning protection module; wherein:
the first lightning protection module and the second lightning protection module are connected in series between two poles of a circuit to be protected;
the connection point of the first lightning protection module and the second lightning protection module is grounded through the third lightning protection module;
the connection point of the first lightning protection module and the second lightning protection module is connected with the midpoint of the voltage equalizing circuit between two poles of the line to be protected;
when the voltage equalizing circuit is not arranged between two poles of the circuit to be protected, or the resistance value of the voltage equalizing circuit is larger than a preset resistance value, two ends of the third lightning protection module are connected with the output end of the voltage applying module to replace connection between the connection point of the first lightning protection module and the second lightning protection module and the midpoint of the voltage equalizing circuit;
the voltage applying module is used for outputting the regulating voltage when the partial voltage of at least one lightning protection module is larger than the safety voltage of the lightning protection module, so that the partial voltages of the three lightning protection modules are smaller than the respective safety voltages.
2. The lightning protection circuit of claim 1, wherein the voltage application module draws power from the line to be protected;
the voltage applying module is a direct current-direct current conversion module.
3. The lightning protection circuit of claim 1, wherein when the line to be protected is a dc bus in an inverter, the voltage application module draws power from an ac branch in the inverter;
the voltage application module is an alternating current-direct current conversion module.
4. The lightning protection circuit according to any one of claims 1 to 3 further comprising: two fusing modules; wherein:
the two ends of a serial branch formed by the first lightning protection module and the second lightning protection module are respectively connected with the two poles of the circuit to be protected through one fusing module.
5. A lightning protection circuit according to any of claims 1 to 3 wherein the line to be protected comprises: a direct current bus in an inverter, or a direct current bus in a junction box of a front stage of the inverter.
6. A control method of a lightning protection circuit, characterized by being applied to the lightning protection circuit according to any one of claims 1 to 5; the control method of the lightning protection circuit comprises the following steps:
determining the partial pressure of each lightning protection module in the lightning protection circuit;
judging whether the partial voltage of at least one lightning protection module in the lightning protection circuit is larger than the self safety voltage or not;
if at least one lightning protection module in the lightning protection circuit has the partial pressure larger than the self safety voltage, controlling a voltage application module in the lightning protection circuit to output the regulating voltage, enabling the partial pressures of the three lightning protection modules to be smaller than the respective safety voltage, and returning to execute the step of determining the partial pressure of each lightning protection module in the lightning protection circuit.
7. The method of claim 6, wherein determining the partial pressure of each lightning protection module in the lightning protection circuit comprises:
and calculating the partial pressure of each lightning protection module by utilizing the partial pressure relation of each lightning protection module and combining the two-pole voltage of the line to be protected.
8. The method of claim 6, further comprising, prior to determining the partial voltage of each lightning protection module in the lightning protection circuit:
judging whether the difference between the negative electrode potential of the circuit to be protected and the ground level is smaller than or equal to a preset difference value;
and if the difference between the negative electrode potential of the circuit to be protected and the ground level is smaller than or equal to the preset difference value, executing the step of determining the partial pressure of each lightning protection module in the lightning protection circuit.
9. The method for controlling a lightning protection circuit according to claim 8, wherein when the line to be protected is a dc bus of an inverter, or the line to be protected is directly connected to the dc bus of the inverter, determining whether a difference between a negative potential of the line to be protected and a ground level is less than or equal to the preset difference value includes:
judging whether the negative electrode of the inverter is grounded or not, or whether the inverter works in a PID suppression mode or not;
and if the negative electrode of the inverter is grounded or the inverter works in the PID suppression module, judging that the difference between the negative electrode potential of the circuit to be protected and the ground level is smaller than or equal to the preset difference value.
10. The method according to claim 8, wherein when the line to be protected is not a dc bus of an inverter and the line to be protected is not directly connected to the dc bus of the inverter, determining whether a difference between a negative potential of the line to be protected and a ground level is smaller than the preset difference comprises:
judging whether the negative electrode of the circuit to be protected is grounded or not;
and if the negative electrode of the circuit to be protected is grounded, judging that the difference between the potential of the negative electrode of the circuit to be protected and the ground level is smaller than or equal to the preset difference value.
11. An inverter, comprising: an inverter module, a dc bus, an ac branch and a lightning protection circuit according to any one of claims 1 to 5; wherein:
the direct current side of the inversion module is connected with the output of the front stage through the direct current bus, and the alternating current side of the inversion module is connected with the alternating current branch;
the lightning protection circuit is arranged between two poles of the direct current bus.
12. An inverter system, comprising: at least one combiner box and the inverter of claim 11; wherein:
the output end of the combiner box is connected with the direct current side of the inverter.
13. The inverter system according to claim 12, wherein a lightning protection circuit according to any one of claims 1 to 5 is provided between two poles of a direct current bus in the junction box.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101171228B1 (en) * | 2012-03-19 | 2012-08-06 | 국방과학연구소 | Protection devices for power line against high altitude electromagnetic pulse |
| CN104253426A (en) * | 2014-09-03 | 2014-12-31 | 烽火通信科技股份有限公司 | Lightning protection circuit and lightning protection method for direct-current power supply port of communication equipment |
| CN208862564U (en) * | 2018-07-18 | 2019-05-14 | 河南森源电气股份有限公司 | A kind of photovoltaic DC-to-AC converter lightning protection device |
| CN111490672A (en) * | 2020-02-28 | 2020-08-04 | 深圳市槟城电子有限公司 | Power protection circuit, power supply and electronic equipment |
| CN112467705A (en) * | 2019-09-06 | 2021-03-09 | 阳光电源股份有限公司 | Lightning protection device and inverter |
| CN214204944U (en) * | 2021-01-19 | 2021-09-14 | 英飞特电子（杭州）股份有限公司 | Lightning protection circuit |
-
2021
- 2021-11-17 CN CN202111362707.3A patent/CN113922652B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101171228B1 (en) * | 2012-03-19 | 2012-08-06 | 국방과학연구소 | Protection devices for power line against high altitude electromagnetic pulse |
| CN104253426A (en) * | 2014-09-03 | 2014-12-31 | 烽火通信科技股份有限公司 | Lightning protection circuit and lightning protection method for direct-current power supply port of communication equipment |
| CN208862564U (en) * | 2018-07-18 | 2019-05-14 | 河南森源电气股份有限公司 | A kind of photovoltaic DC-to-AC converter lightning protection device |
| CN112467705A (en) * | 2019-09-06 | 2021-03-09 | 阳光电源股份有限公司 | Lightning protection device and inverter |
| CN111490672A (en) * | 2020-02-28 | 2020-08-04 | 深圳市槟城电子有限公司 | Power protection circuit, power supply and electronic equipment |
| CN214204944U (en) * | 2021-01-19 | 2021-09-14 | 英飞特电子（杭州）股份有限公司 | Lightning protection circuit |
Non-Patent Citations (1)
| Title |
|---|
| 并联式防雷模块;张海文等;农村电气化;第57页 * |
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