CN112769106A - Self-adaptive current protection method, system and storage medium - Google Patents
Self-adaptive current protection method, system and storage medium Download PDFInfo
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- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
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Abstract
The invention discloses a self-adaptive current protection method, a self-adaptive current protection system and a storage medium, wherein the method comprises the following steps: calculating the equivalent impedance of the system in real time by using an STF algorithm based on the acquired voltage and current of the cycle before the fault of the power distribution system; acquiring fault current, and judging the fault type based on the fault current; calculating a protection setting value based on the system equivalent impedance and the fault type; and when a fault occurs, comparing the protection setting value with a fault sampling value, sending a control instruction to protect equipment based on a comparison result, controlling the running state of the protection equipment, and completing self-adaptive current protection. The method adopts the STF algorithm to calculate the equivalent impedance of the system in real time, judges the fault type, and finally calculates the protection setting value based on the equivalent impedance of the system and the fault type, thereby realizing the setting of the self-adaptive instantaneous current quick-break protection, effectively improving the protection performance of the distribution network containing DG and energy storage and having important popularization and application values.
Description
Technical Field
The invention belongs to the technical field of safe operation of power systems, and particularly relates to a self-adaptive current protection method, a self-adaptive current protection system and a storage medium.
Background
Under the background of environmental pollution pressure and rapid development of clean energy in China, a large number of Distributed power Supplies (DGs) such as photovoltaic power, wind power and the like are connected into a power grid. The DG brings clean electric energy, and meanwhile, the traditional single-source radial structure of the power distribution network is changed, and certain influences are brought to the operation strategy, the protection action, the electric energy quality and the like of the traditional power distribution network. The adaptive current protection strategy is formulated for the power distribution network containing the DGs and the energy storage, the advantages of improving the new energy consumption and the operation reliability of the power distribution network by the DGs and the energy storage can be fully exerted, and the disadvantages of protection misoperation/refusal operation and the like are avoided.
Aiming at a self-adaptive current protection strategy of a power distribution network containing DGs and energy storage, a self-adaptive overcurrent protection system which is constructed in a hybrid hierarchical management mode based on centralized intelligence and distributed intelligence coordination is provided, but the system has higher requirements on system software and hardware; aiming at the problem of current quick-break and time-limited current quick-break protection misoperation possibly caused by photovoltaic access, a protection improvement setting scheme based on a fault position and photovoltaic output power is provided, but the method is mainly suitable for a power distribution network accessed by a constant power control mode photovoltaic.
Disclosure of Invention
Aiming at the problems, the invention provides a self-adaptive current protection method, a system and a storage medium, which adopt a system equivalent impedance based on STF algorithm to calculate in real time, judge the fault type, finally calculate the protection setting value based on the system equivalent impedance and the fault type, realize the setting of self-adaptive instantaneous current quick-break protection, can effectively improve the protection performance of a distribution network containing DG and energy storage, and have important popularization and application values.
In order to achieve the technical purpose and achieve the technical effects, the invention is realized by the following technical scheme:
in a first aspect, the present invention provides an adaptive current protection method, including:
calculating the equivalent impedance of the power distribution system in real time by using an STF algorithm based on the acquired voltage and current of the cycle before the fault of the power distribution system;
acquiring fault current, and judging the fault type based on the fault current;
calculating a protection setting value based on the system equivalent impedance and the fault type;
and when a fault occurs, comparing the protection setting value with a fault sampling value, sending a control instruction to protect equipment based on a comparison result, controlling the running state of the protection equipment in the power distribution system, and finishing self-adaptive current protection.
Optionally, the method for calculating the equivalent impedance of the system includes the following steps:
extracting a current fundamental component i (t) and a voltage fundamental component u (t) of a cycle before a system fault, wherein,
in the formula: u. ofs(t) is the voltage of the power supply,
Asis the supply voltage amplitude, w is the system angular frequency,
is an initialPhase, RsFor protection of the system equivalent resistance at the back side of the device, LsEquivalent inductance for protecting a system at the back side of the equipment;
r is to besAnd LsAs state quantities us(t) is a known parameter, i (t), u (t) are input quantities, and equation (1) is discretized into the STF standard form:
in the formula, x1Corresponding protection equipment back system equivalent resistance Rs，x2Equivalent inductance L of corresponding protection equipment back side systems，x1(k +1) represents the equivalent resistance R of the system on the back side of the protection devicesThe (k +1) th sampling value; x is the number of2(k +1) represents the equivalent inductance L of the system on the backside of the protection devicesSample value of (k +1) < th > time, TsIs a sampling period;
if the state quantity is not changed, the following are:
combining the formula (2) and the formula (3) to obtain a mathematical model of the STF algorithm, realizing state estimation and obtaining RsAnd LsFinally, the equivalent impedance Z of the system is obtainedS＝RS+jwLS。
Optionally, the method for determining the fault type includes:
and substituting the fault current into a set criterion formula to obtain a fault type, wherein the criterion formula is as follows:
in the formula Iaf、IcfRespectively phase A and C currents, KfIs a constant coefficient.
Optionally, the calculation formula of the protection setting value is as follows:
in the formula Iz,setTo protect the setting value, KrelIs a reliability factor; kkThe fault type coefficient is obtained, and different fault types correspond to different fault type coefficients; e is the system equivalent potential; zLFor protecting the line where the equipment is located; zSIs the equivalent impedance of the system.
Optionally, when the fault type is a three-phase short circuit, the fault type coefficient is 1; when the fault type is a two-phase short circuit, the fault type system is selected
Optionally, when a fault occurs, comparing the protection setting value with a fault sampling value, and sending a control instruction to protect the device based on the comparison result, so as to control the operating state of the protection device, including:
and when the system has a short-circuit fault, comparing the protection setting value with the short-circuit current, and if the short-circuit current is greater than or equal to the protection setting value, sending a tripping instruction of the protection equipment to the protection equipment, controlling the protection equipment to execute a tripping action, so as to realize fault isolation.
Optionally, the short-circuit current is calculated by the following formula:
in the formula, KkIs a fault type coefficient, different fault types correspond to different fault type coefficients, E is a system equivalent potential, ZSIs the equivalent impedance of the system, ZLAnd beta is the ratio of the distance from the protection equipment to the fault point to the total length of the line.
Optionally, after the step of sending the trip instruction of the protection device to the protection device, the method further includes:
and calculating the trip protection range, wherein the calculation formula is as follows:
wherein, KrelFor the reliability factor, αzIs the trip protection range.
In a second aspect, the present invention provides an adaptive current protection system, comprising a processor and a storage medium;
the storage medium is used for storing instructions;
the processor is configured to operate in accordance with the instructions to perform the steps of the method according to any one of the first aspects.
In a third aspect, the invention provides a computer-readable storage medium having stored thereon a computer program which, when executed by a processor, performs the steps of the method of any one of the first aspect.
Compared with the prior art, the invention has the beneficial effects that:
(1) according to the method, the system equivalent impedance is calculated in real time based on the STF algorithm, the short-circuit fault type is judged, the protection setting value is finally calculated based on the system equivalent impedance and the fault type, the setting of the self-adaptive instantaneous current quick-break protection is realized, the protection setting value can be changed in real time according to the system fault type and the change of the operation mode, and the action performance of the protection is improved.
(2) Aiming at the DG and energy storage power distribution network, the invention can prolong the protection range in the line range, so that the system can rapidly remove the faults in a larger range, and has a promoting effect on ensuring the safe and stable operation of the system.
Drawings
In order that the present disclosure may be more readily and clearly understood, reference is now made to the following detailed description of the present disclosure taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a general flow chart of an adaptive current protection method according to an embodiment of the present invention;
FIG. 2 is a block diagram of a DG-containing and energy storage distribution network in accordance with one embodiment of the present invention;
FIG. 3 shows the fault current and setting value of the protection device S3 when the tail end of L3 has a fault;
fig. 4 shows fault current and setting value of the protection device S1 when the end of L1 fails.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the scope of the invention.
The following detailed description of the principles of the invention is provided in connection with the accompanying drawings.
Example 1
The embodiment of the invention provides a self-adaptive current protection method which is applicable to a system comprising a distributed power supply and an energy storage power distribution network, and specifically comprises the following steps:
(1) calculating the equivalent impedance of the system in real time by using an STF algorithm based on the acquired voltage and current of the cycle before the fault of the power distribution system;
in a specific implementation manner of the embodiment of the present invention, the method for calculating the equivalent impedance of the system includes the following steps:
(1.1) extracting a current fundamental component i (t) and a voltage fundamental component u (t) of a cycle before a system fault, wherein,
in the formula: u. ofs(t) is the voltage of the power supply,
Asis the supply voltage amplitude, w is the system angular frequency,
to an initial phase, RsFor protection of the system equivalent resistance at the back side of the device, LsEquivalent inductance for protecting a system at the back side of the equipment;
in the process of the specific embodiment, the FFT algorithm may be used to extract the current fundamental component i (t) and the voltage fundamental component u (t) of the cycle before the system fault, and the extraction process may be implemented by using the prior art, which is not described in detail herein;
(1.2) adding RsAnd LsAs state quantities us(t) is a known parameter, i (t), u (t) are input quantities, and equation (1) is discretized into the STF standard form:
in the formula, x1Corresponding protection equipment back system equivalent resistance Rs，x2Equivalent inductance L of corresponding protection equipment back side systems，x1(k +1) represents the equivalent resistance R of the system on the back side of the protection devicesThe (k +1) th sampling value; x is the number of2(k +1) represents the equivalent inductance L of the system on the backside of the protection devicesSample value of (k +1) < th > time, TsIs a sampling period;
(1.3) if the state quantity is not changed, the following are provided:
(1.4) combining the formula (2) and the formula (3) to obtain a mathematical model of the STF algorithm, realizing state estimation and obtaining RsAnd LsFinally, the equivalent impedance Z of the system is obtainedS＝RS+jwLS。
(2) Acquiring fault current, and judging the fault type based on the fault current;
in a specific implementation manner of the embodiment of the present invention, the method for determining the fault type includes:
the self-adaptive current protection provided by the invention can self-adaptively adjust the protection setting value according to the system operation mode and the fault type, thereby improving the protection performance. The self-adaptive current protection real-time monitoring short-circuit fault type and the calculation of system impedance are carried out, and the judgment of the short-circuit fault type is as follows:
in the formula Iaf、IcfRespectively phase A and C currents, KfIs a constant coefficient.
And substituting the fault current into a set criterion formula to obtain the fault type.
(3) Calculating a protection setting value based on the system equivalent impedance and the fault type;
in a specific implementation manner of the embodiment of the present invention, the calculation formula of the protection setting value is as follows:
in the formula Iz,setTo protect the setting value, KrelIs a reliability factor; kkThe fault type coefficient is obtained, and different fault types correspond to different fault type coefficients; e is the system equivalent potential; zLFor protecting the line where the equipment is located; zSIs the equivalent impedance of the system.
In the specific implementation process, the following settings can be made: when the fault type is three-phase short circuit, the fault type coefficient is 1; when the fault type is a two-phase short circuit, the fault type system is selected
(4) And when a fault occurs, comparing the protection setting value with a fault sampling value, sending a control instruction to protect equipment based on a comparison result, controlling the running state of the protection equipment, and completing self-adaptive current protection.
In a specific implementation manner of the embodiment of the present invention, when a fault occurs, comparing the protection setting value with a fault sampling value, and sending a control instruction to protect a device based on a comparison result, to control an operating state of the protection device, includes:
and when the system has a short-circuit fault, comparing the protection setting value with the short-circuit current, and if the short-circuit current is greater than or equal to the protection setting value, sending a tripping instruction of the protection equipment to the protection equipment, controlling the protection equipment to execute a tripping action, so as to realize fault isolation.
The calculation formula of the short-circuit current is as follows:
in the formula, KkIs a fault type coefficient, different fault types correspond to different fault type coefficients, E is a system equivalent potential, ZSIs the equivalent impedance of the system, ZLAnd beta is the ratio of the distance from the protection equipment to the fault point to the total length of the line.
Further, in a specific implementation manner of the embodiment of the present invention, after the step of sending the trip instruction of the protection device to the protection device, the method further includes:
and calculating the trip protection range, wherein the calculation formula is as follows:
wherein, KrelFor the reliability factor, αzIs the trip protection range.
In conclusion, compared with the traditional current quick-break protection, under a similar operation mode, the self-adaptive current protection provided by the invention can meet the requirement of current quick-break action and is in an optimal state, so that the line protection range is effectively prolonged.
Example 2
Based on the same inventive concept as embodiment 1, the embodiment of the present invention provides an adaptive current protection system, including a processor and a storage medium;
the storage medium is used for storing instructions;
the processor is configured to operate in accordance with the instructions to perform the steps of the method according to any of embodiment 1.
Example 3
Based on the same inventive concept as embodiment 1, an embodiment of the present invention provides a computer-readable storage medium on which a computer program is stored, which, when executed by a processor, implements the steps of the method of any one of embodiments 1.
The following is a specific case of adopting the self-adaptive current protection method provided by the invention:
taking a 10kV power distribution network as an example, the basic network topology structure of the system is shown in fig. 2, an energy storage device is connected to a bus B, and distributed wind power is connected to a bus C. And in order to prevent the DG from self-protecting and quitting the operation under the fault condition, a protective device S6 is additionally arranged on the back side of the bus C to isolate the upstream fault and improve the reliability of the DG for supplying power to the downstream load.
The system parameters are set as follows: the reference capacity is 100MV & A, and the reference voltage is 10.5 kV; the line is a uniform line, the line resistance is 0.236 omega/km, the line inductance is 2.55mH/km, L1 is 5km, L2 is 7km, L3 is 5km, L4 is 7km, and L5 is 8 km; loads on the bus B, C, D are respectively 1.50+ j0.49MV & A, 3.69+ j1.22MV & A and 1.82+ j0.61MV & A, and loads at the tail ends of the lines L2 and L5 are respectively 1.62+ j0.51MV & A and 1.93+ j0.65MV & A; the DG capacity is 3 MV.A, and the energy storage capacity is 200 kW.
A simulation system is built based on a PSCAD/EMTDC platform, and an Intel quad-core 2.5GHz processor and a 4GB memory are configured in a computer.
In order to reflect the protection action condition when different positions of the same line have faults, the short-circuit fault condition is set as follows: in 0-0.5 s, no fault exists; in the time period of 0.5 s-0.8 s, a short-circuit fault occurs at the line 1/3; in the time interval of 1.0 s-1.3 s, a short-circuit fault occurs at the line 2/3; and in the time period of 1.5 s-1.8 s, the tail end of the line has short-circuit fault.
Firstly, setting L3 to generate three-phase short circuit, and obtaining fault current flowing through each key protection device and protection setting values of the self-adaptive current method adopted by the invention as shown in Table 1, wherein FIG. 3 is the fault current and the setting values of the protection device S3 when the L3 tail end is in fault.
As can be seen from Table 1:
1) when three-phase short-circuit faults occur at the positions of lines 1/3 and 2/3 and at the tail end of the L3, fault currents flowing through the protection devices S1 and S4 are always smaller than the setting value of the fault currents, so that the protection devices S1 and S4 can not act reliably.
2) When three-phase short circuit occurs at the positions of lines 1/3 and 2/3 of L3, fault currents flowing through protection equipment S3 and S6 are both larger than protection setting values, and therefore both the fault currents can reliably act, faults are isolated, DG can continuously supply power to a bus C and loads of a downstream line, and renewable energy consumption is guaranteed. When the end of the L3 line has a fault, the fault current flowing through the protection device S3 is smaller than the setting value thereof, and the fault current flowing through the protection device S6 is larger than the setting value thereof, so that the protection device S3 does not operate, and the protection device S6 operates. It can be seen that due to the protection matching requirement, the self-adaptive instantaneous current quick-break cannot protect the whole length of the line, so that the protection device S3 cannot instantaneously remove the fault and needs to rely on the current II section to protect the signaling action.
In addition, as can be seen from fig. 3, when the L3 line end fails, the instantaneous quick-break protection range can be extended from 78.8% to 86.5% by using the adaptive current protection method of the present invention, which indicates the advantage of the adaptive protection method in increasing the protection range.
The L1 is set to generate a three-phase short circuit, and the fault current flowing through each key protection device and the protection setting value of the adaptive current protection method adopted by the invention are shown in table 2, and fig. 4 shows the fault current and the setting value of the protection device S1 when the L1 tail end fails.
As can be seen from table 2 and fig. 4:
1) when three-phase short circuit occurs at the positions of lines 1/3 and 2/3 of the L1, fault current flowing through the protection equipment S1 is larger than a protection setting value, and therefore both the fault current and the fault current can reliably act; when the L1 line end fails, the fault current flowing through the protection device S1 is less than its setting value, and thus the protection device does not operate. As can be seen from fig. 4, if the instantaneous current snap strategy setting before the DG and the energy storage device are connected is adopted, the instantaneous snap protection range of the protection device S1 exceeds the entire length of the line, and the selectivity is lost. Under the same condition, the adaptive current protection method can protect the first 92.3 percent of the circuit, and shows good protection performance.
2) When three-phase short-circuit faults occur at the positions of lines 1/3 and 2/3 and at the tail end of the L1, fault currents flowing through the protection devices S3 and S4 are always smaller than the setting value of the fault currents, so that the protection devices S3 and S4 can both be prevented from acting, and reliable operation of non-fault feeder lines is guaranteed.
The simulation fault setting is three-phase short-circuit fault, when the two-phase short-circuit fault is set, the self-adaptive current protection method has similar performance, can ensure selectivity and reliable action/non-action, prolongs the protection range in the circuit range, and does not need to be repeated about simulation results and analysis.
Therefore, the adaptive current protection strategy of the invention adopts the STF algorithm to calculate the equivalent impedance of the system in real time, and realizes the setting of the adaptive instantaneous current quick-break protection by judging the fault type. The strategy can change the protection setting value in real time according to the system fault type and the operation mode change, and the protection range is extended in the range of the line, so that the system can rapidly remove faults in a larger range, the action performance of protection is improved, and the promotion effect on ensuring the safe and stable operation of the system is achieved.
As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
While the present invention has been described with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, which are illustrative and not restrictive, and it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention as defined in the appended claims.
The foregoing shows and describes the general principles and broad features of the present invention and advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (10)
1. An adaptive current protection method, comprising:
calculating the equivalent impedance of the system in real time by using an STF algorithm based on the acquired voltage and current of the cycle before the fault of the power distribution system;
acquiring fault current, and judging the fault type based on the fault current;
calculating a protection setting value based on the system equivalent impedance and the fault type;
and when a fault occurs, comparing the protection setting value with a fault sampling value, sending a control instruction to protect equipment based on a comparison result, controlling the running state of the protection equipment in the power distribution system, and finishing self-adaptive current protection.
2. The adaptive current protection method according to claim 1, wherein the calculation method of the system equivalent impedance comprises the following steps:
extracting a current fundamental component i (t) and a voltage fundamental component u (t) of a cycle wave before the fault of the power distribution system, wherein,
in the formula: u. ofs(t) is the voltage of the power supply,
Asis the supply voltage amplitude, w is the system angular frequency,
to an initial phase, RsFor protection of the system equivalent resistance at the back side of the device, LsEquivalent inductance for protecting a system at the back side of the equipment;
r is to besAnd LsAs state quantities us(t) is a known parameter, i (t), u (t) are input quantities, and equation (1) is discretized into the STF standard form:
in the formula, x1Corresponding protection equipment back system equivalent resistance Rs，x2Equivalent inductance L of corresponding protection equipment back side systems，x1(k +1) represents the equivalent resistance R of the system on the back side of the protection devicesThe (k +1) th sampling value; x is the number of2(k +1) represents the equivalent inductance L of the system on the backside of the protection devicesSample value of (k +1) < th > time, TsIs a sampling period;
if the state quantity is not changed, the following are:
combining the formula (2) and the formula (3) to obtain a mathematical model of the STF algorithm, realizing state estimation and obtaining RsAnd LsFinally, the equivalent impedance Z of the system is obtainedS＝RS+jwLS。
3. An adaptive current protection method according to claim 1, characterized in that: the method for judging the fault type comprises the following steps:
and substituting the fault current into a set criterion formula to obtain a fault type, wherein the criterion formula is as follows:
in the formula Iaf、IcfRespectively phase A and C currents, KfIs a constant coefficient.
4. The adaptive current protection method according to claim 1, wherein the calculation formula of the protection setting value is as follows:
in the formula Iz,setTo protect the setting value, KrelIs a reliability factor; kkThe fault type coefficient is obtained, and different fault types correspond to different fault type coefficients; e is the system equivalent potential; zLFor protecting the line where the equipment is located; zSIs the equivalent impedance of the system.
5. An adaptive current protection method according to claim 4, characterized in that: when the fault type is three-phase short circuit, the fault type coefficient is 1; when the fault type is a two-phase short circuit, the fault type system is selected
6. The adaptive current protection method according to claim 1, wherein the comparing the protection setting value with the fault sampling value when the fault occurs, and sending a control instruction to protect equipment based on the comparison result, and controlling the operation state of the protection equipment comprises:
and when the system has a short-circuit fault, comparing the protection setting value with the short-circuit current, and if the short-circuit current is greater than or equal to the protection setting value, sending a tripping instruction of the protection equipment to the protection equipment, controlling the protection equipment to execute a tripping action, so as to realize fault isolation.
7. The adaptive current protection method according to claim 6, wherein the short-circuit current is calculated by the formula:
in the formula, KkIs a fault type coefficient, different fault types correspond to different fault type coefficients, E is a system equivalent potential, ZSIs the equivalent impedance of the system, ZLAnd beta is the ratio of the distance from the protection equipment to the fault point to the total length of the line.
8. The adaptive current protection method of claim 6, wherein said step of sending a protection device trip command to a protection device further comprises, after said step of sending a protection device trip command to a protection device:
and calculating the trip protection range, wherein the calculation formula is as follows:
wherein, KrelFor the reliability factor, αzIs the trip protection range.
9. An adaptive current protection system, characterized by: comprising a processor and a storage medium;
the storage medium is used for storing instructions;
the processor is configured to operate in accordance with the instructions to perform the steps of the method according to any one of claims 1 to 8.
10. A computer-readable storage medium having stored thereon a computer program, characterized in that: the program when executed by a processor implements the steps of the method of any one of claims 1 to 8.
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| CN115469175A (en) * | 2022-07-12 | 2022-12-13 | 国网四川省电力公司绵阳供电公司 | Power distribution network fault interval detection method and system based on quick-break protection |
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Non-Patent Citations (1)
| Title |
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| 孙长如: "含分布式电源配电网自适应保护研究", 《中国优秀博硕士学位论文全文数据库(硕士)工程科技Ⅱ辑》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN115469175A (en) * | 2022-07-12 | 2022-12-13 | 国网四川省电力公司绵阳供电公司 | Power distribution network fault interval detection method and system based on quick-break protection |
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Application publication date: 20210507 |