CN108092242B - Multi-voltage-level power grid inverse time-limit current protection method and device - Google Patents
Multi-voltage-level power grid inverse time-limit current protection method and device Download PDFInfo
- Publication number
- CN108092242B CN108092242B CN201711232504.6A CN201711232504A CN108092242B CN 108092242 B CN108092242 B CN 108092242B CN 201711232504 A CN201711232504 A CN 201711232504A CN 108092242 B CN108092242 B CN 108092242B
- Authority
- CN
- China
- Prior art keywords
- protection device
- protection
- voltage
- time
- inverse
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 28
- 230000009471 action Effects 0.000 claims abstract description 96
- 230000005540 biological transmission Effects 0.000 claims description 17
- 230000001681 protective effect Effects 0.000 claims description 16
- 238000010586 diagram Methods 0.000 description 11
- 238000004590 computer program Methods 0.000 description 7
- 230000008569 process Effects 0.000 description 7
- 230000006870 function Effects 0.000 description 5
- 230000004048 modification Effects 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- 238000003860 storage Methods 0.000 description 3
- 230000008859 change Effects 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000007123 defense Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- 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
- H02H7/26—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/08—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess current
- H02H3/093—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess current with timing means
-
- H—ELECTRICITY
- 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
- H02H7/04—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 for transformers
-
- H—ELECTRICITY
- 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
- H02H7/22—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 for distribution gear, e.g. bus-bar systems; for switching devices
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H1/00—Details of emergency protective circuit arrangements
- H02H1/0092—Details of emergency protective circuit arrangements concerning the data processing means, e.g. expert systems, neural networks
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Emergency Protection Circuit Devices (AREA)
Abstract
The invention provides an inverse time-lag current protection method and device for a multi-voltage-level power grid, which comprises the steps of firstly determining respective inverse time-lag current protection action curve equations of a first protection device, a second protection device and a third protection device; then determining the respective action time of the first protection device, the second protection device and the third protection device; finally, inverse time limit current protection is carried out on the multi-voltage-level power grid, so that the inverse time limit protection of the multi-voltage-level power grid is realized, and the fault removal time is shortened; according to the invention, the inverse time-limited current protection action curve equations of the first protection device, the second protection device and the third protection device are corrected through the voltage correction coefficients of the first protection device, the second protection device and the third protection device, so that the action time of inverse time-limited current protection can be effectively improved, and the adaptability of the inverse time-limited current protection to a multi-voltage-level power grid is enhanced.
Description
Technical Field
The invention relates to the technical field of relay protection, in particular to an inverse time-limited current protection method and device for a multi-voltage-level power grid.
Background
The relay protection is a first line of defense of the power system in China, and plays an important role in ensuring the safety, economy, stable operation and the like of the power system. The current relay protection has a timing over-current protection and an inverse time-limited current protection, wherein the timing over-current protection is widely applied to a power grid in China, has fixed action time and is irrelevant to the size of short-circuit current. In order to meet the requirement of protection selectivity, the action time of a protection device is increased step by step from a user to a power supply, so that in a circuit with multi-stage protection, the action time limit of overcurrent protection close to a power supply end is too long, when the circuit has a serious fault, short-circuit current is very large, stable operation of power equipment and a system is influenced, the fault needs to be protected and rapidly removed, but the fault cannot be rapidly removed due to fixed action time of the timed overcurrent protection.
The action time of the inverse time limit current protection is in inverse proportion relation with the magnitude of the fault current, the larger the fault current is, the shorter the action time is, the smaller the fault current is, the longer the action time is, and the action performance is better than the timing time limit current protection. The inverse time limit current protection in the prior art adopts zero sequence current, is greatly influenced by fault positions, a transformer can block a zero sequence current path, fixed inverse time limit current protection can only be applied to a power grid with the same voltage level, and the cooperation between backup protection of power grids with different voltage levels mainly depends on overcurrent protection with fixed time limits. And when the fault point is far away from the protection installation position, the zero sequence current is small, and the inverse time limit current protection time is long.
Disclosure of Invention
In order to overcome the defects that the inverse time limit current protection time is long and the inverse time limit current protection method is not suitable for power grids with different voltage levels in the prior art, the invention provides the inverse time limit current protection method for the power grids with multiple voltage levels, which comprises the steps of firstly determining respective inverse time limit current protection action curve equations of a first protection device, a second protection device and a third protection device; then determining the action time of the first protection device, the second protection device and the third protection device according to the inverse time limit current protection action curve equation of the first protection device, the second protection device and the third protection device; and finally, performing inverse time-lag current protection on the multi-voltage-class power grid according to the respective action time of the first protection device, the second protection device and the third protection device, so that inverse time-lag protection of the multi-voltage-class power grid is realized, and the fault removal time is shortened.
In order to achieve the purpose of the invention, the invention adopts the following technical scheme:
on one hand, the invention provides an inverse time-lag current protection method for a multi-voltage-class power grid, wherein the multi-voltage-class power grid comprises a first equivalent power source, a transformer and a second equivalent power source, the first equivalent power source is connected with the transformer through a first bus, the transformer is connected with the second equivalent power source through a second bus, a power transmission line and a third bus in sequence, a first protection device is installed on one side of the power transmission line close to the second bus, a second protection device is installed on a line between the transformer and the second bus, and a third protection device is installed on a line between the transformer and the first bus, the method comprises the following steps:
determining respective inverse time limit current protection action curve equations of the first protection device, the second protection device and the third protection device;
determining the action time of the first protection device, the second protection device and the third protection device according to the inverse time limit current protection action curve equations of the first protection device, the second protection device and the third protection device;
and performing inverse time-limited current protection on the multi-voltage-class power grid according to the respective action time of the first protection device, the second protection device and the third protection device.
The determining the action time of the first protection device, the second protection device and the third protection device according to the inverse time limit current protection action curve equation of the first protection device, the second protection device and the third protection device comprises the following steps:
determining a voltage parameter and a current parameter according to respective inverse time limit current protection action curve equations of the first protection device, the second protection device and the third protection device;
and determining the action time of each of the first protection device, the second protection device and the third protection device according to the voltage parameter and the current parameter.
The inverse time limit current protection action curve equation of the first protection device is determined according to the formula (1):
wherein, t 1 Indicating the time of operation of the first protection device, I 1 Representing the measured current at the first protection device, I p Denotes the starting current, K 1 Represents a voltage correction coefficient of the first protection device, and
U e1 indicating the rated voltage, U, of the first protection means 1 Representing the measured voltage at the first protection device, m 1 The voltage margin of the first protection device is indicated, a represents a current parameter, and r represents a voltage parameter.
The inverse time limit current protection action curve equation of the second protection device is determined according to the formula (2):
wherein, t 2 Indicating the time of operation of the second protection device, I 2 Representing the measured current at the second protection device, K 2 Voltage correction factor representing second protection deviceAnd is made of
U e2 Denotes the rated voltage, m, of the second protective device 2 Denotes a voltage margin, U 'of the second protection device' 2 Denotes the compensation voltage at the second protection device, and U' 2 ＝U 2 -I 2 ×kZ T ，U 2 Indicating the measured voltage at the second protection device, Z T Represents the impedance of the transformer and k represents the compensation factor.
The inverse time limit current protection action curve equation of the second protection device is determined according to the formula (3):
wherein, t 3 Represents the operating time of the third protection device, I 3 Representing the measured current at the third protection device, K 3 A voltage correction coefficient of the third protection device, and
U e3 denotes the rated voltage, m, of the third protective device 3 Indicating the voltage margin, U, of the third protection means 3 Representing the measured voltage at the third protection device.
Determining a voltage parameter and a current parameter according to respective inverse time-limit current protection action curve equations of a first protection device, a second protection device and a third protection device, wherein the voltage parameter and the current parameter comprise the following steps:
based on t 2 -t 1 ＝Δt 21 ，t 3 -t 2 ＝Δt 32 And obtaining A and r according to respective inverse time limit current protection action curve equations of the first protection device, the second protection device and the third protection device, wherein delta t 21 Representing the difference in level, Δ t, between the second and the first protection means 32 Indicating the level difference between the third protection device and the second protection device.
The inverse time limit current protection of the multi-voltage-class power grid according to the respective action time of the first protection device, the second protection device and the third protection device comprises the following steps:
if the tail end of the power transmission line fails, t passes 1 Then, the first protection device acts, and the second protection device and the third protection device do not act;
if the second bus fails, t passes 2 Then, the second protection device acts, and the first protection device and the third protection device do not act;
if the transformer fails, t is passed 3 Then, the third protection device is activated, and the first protection device and the second protection device are deactivated.
On the other hand, the invention also provides a multi-voltage-class power grid inverse time-lag current protection device, the multi-voltage-class power grid comprises a first equivalue power supply, a transformer and a second equivalue power supply, the first equivalue power supply is connected with the transformer through a first bus, the transformer is connected with the second equivalue power supply through a second bus, a power transmission line and a third bus in sequence, the first protection device is installed on one side of the power transmission line close to the second bus, the second protection device is installed on a line between the transformer and the second bus, and the third protection device is installed on a line between the transformer and the first bus, and the multi-voltage-class power grid inverse time-lag current protection device comprises:
the first determining module is used for determining the inverse time limit current protection action curve equations of the first protection device, the second protection device and the third protection device respectively;
the second determining module is used for determining the action time of the first protection device, the second protection device and the third protection device according to the inverse time limit current protection action curve equation of the first protection device, the second protection device and the third protection device;
and the protection module is used for carrying out inverse time limit current protection on the multi-voltage-class power grid according to the respective action time of the first protection device, the second protection device and the third protection device.
The second determining module includes:
the parameter determining unit is used for determining a voltage parameter and a current parameter according to the inverse time limit current protection action curve equations of the first protection device, the second protection device and the third protection device;
and the time determining unit is used for determining the action time of each of the first protection device, the second protection device and the third protection device according to the voltage parameter and the current parameter.
The first determination module comprises a first equation determination unit which determines an inverse time-limited current protection action curve equation of the first protection device according to equation (1):
wherein, t 1 Represents the operating time of the first protection device, I 1 Representing the measured current at the first protection device, I p Denotes the starting current, K 1 Represents a voltage correction coefficient of the first protection device, and
U e1 indicating the rated voltage, U, of the first protection means 1 Representing the measured voltage at the first protection device, m 1 The voltage margin of the first protection device is indicated, a represents a current parameter, and r represents a voltage parameter.
The first determination module further includes a second equation determination unit that determines an inverse time-limit current protection action curve equation of the second protection device according to equation (2):
wherein, t 2 Indicating the time of operation of the second protection device, I 2 Representing the measured current at the second protection device, K 2 Represents a voltage correction coefficient of the second protection device, and
U e2 indicating a second protective deviceRated voltage, m 2 Denotes a voltage margin, U 'of the second protection device' 2 Denotes the compensation voltage at the second protection device, and U' 2 ＝U 2 -I 2 ×kZ T ，U 2 Indicating the measured voltage at the second protection device, Z T Represents the impedance of the transformer and k represents the compensation factor.
The first determination module comprises a third equation determination unit, and the third equation determination unit determines an inverse time limit current protection action curve equation of the second protection device according to equation (3):
wherein, t 3 Represents the operating time of the third protection device, I 3 Denotes the measured current at the third protective device, K 3 A voltage correction coefficient of the third protection device, and
U e3 denotes the rated voltage, m, of the third protective device 3 Indicating the voltage margin of the third protection device, U 3 Representing the measured voltage at the third protection device.
The parameter determining unit is specifically configured to:
based on t 2 -t 1 ＝Δt 21 ，t 3 -t 2 ＝Δt 32 And obtaining A and r according to respective inverse time limit current protection action curve equations of the first protection device, the second protection device and the third protection device, wherein delta t 21 Representing the difference in level, Δ t, between the second protection device and the first protection device 32 Indicating the level difference between the third protection device and the second protection device.
The protection module is specifically configured to:
if the tail end of the power transmission line fails, t passes 1 Then, the first protection device acts, and the second protection device and the third protection device do not act;
if a failure of the second bus bar occurs,passing through t 2 Then, the second protection device acts, and the first protection device and the third protection device do not act;
if the transformer fails, t is passed 3 Then, the third protection device is activated, and the first protection device and the second protection device are deactivated.
Compared with the closest prior art, the technical scheme provided by the invention has the following beneficial effects:
the invention provides an inverse time limit current protection method for a multi-voltage-level power grid, which comprises the steps of firstly determining respective inverse time limit current protection action curve equations of a first protection device, a second protection device and a third protection device; then determining the action time of the first protection device, the second protection device and the third protection device according to the inverse time limit current protection action curve equation of the first protection device, the second protection device and the third protection device; finally, inverse time limit current protection is carried out on the multi-voltage-level power grid according to the respective action time of the first protection device, the second protection device and the third protection device, so that the inverse time limit protection of the multi-voltage-level power grid is realized, and the fault removal time is shortened;
the invention provides an inverse time-lag current protection device for a multi-voltage-class power grid, which comprises a first determination module, a second determination module and a protection module, wherein the first determination module is used for determining respective inverse time-lag current protection action curve equations of a first protection device, a second protection device and a third protection device, and the second determination module is used for determining respective action time of the first protection device, the second protection device and the third protection device according to the respective inverse time-lag current protection action curve equations of the first protection device, the second protection device and the third protection device; the protection module is used for carrying out inverse time limit current protection on the multi-voltage-class power grid according to the action time of the first protection device, the second protection device and the third protection device, so that the inverse time limit protection of the multi-voltage-class power grid is realized, and the fault removal time is shortened;
according to the technical scheme provided by the invention, the natural distribution of the grid voltage under the fault and the change rule of the measured voltage moving along with the fault position are utilized, and the respective inverse time-limited current protection action curve equations of the first protection device, the second protection device and the third protection device are corrected through respective voltage correction coefficients of the first protection device, the second protection device and the third protection device, so that the action time of inverse time-limited current protection can be effectively improved, and the adaptability of the inverse time-limited current protection to a multi-voltage-level grid is enhanced.
Drawings
FIG. 1 is a diagram of a multi-voltage class power grid configuration in an embodiment of the present invention;
fig. 2 is a flow chart of an inverse time-limited current protection method for a multi-voltage class power grid in the embodiment of the invention.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
In one aspect, an embodiment of the present invention provides an inverse time-limited current protection method for a multi-voltage-class power grid, where a structure diagram of the multi-voltage-class power grid is shown in fig. 1, and in fig. 1, G 1 Representing a first equivalent power supply, T representing a transformer, G 2 Representing a second, equal value source, B representing a first busbar, C representing a second busbar, D representing a third busbar, R 1 Denotes a first protective means, R 2 Denotes a second protective device, R 3 Indicating a third protection device and F a point of failure. In particular, the multi-voltage class grid comprises a first equivalent power source G 1 Transformer T and second equivalent power source G 2 First equivalent power source G 1 Is connected with a transformer T through a first bus B, and the transformer T is connected with a second equivalent power supply G 2 The first protection device R is arranged on one side of the power transmission line close to the second bus C 1 A second protection device R is arranged on the line between the transformer T and the second bus C 2 A third protection device R is arranged on the line between the transformer T and the first bus B 3 The specific flow chart of the inverse time-limited current protection method for the multi-voltage-class power grid provided by the embodiment of the invention is shown in fig. 2, and the specific process is as follows:
s101: determining respective inverse time limit current protection action curve equations of a first protection device, a second protection device and a third protection device;
s102: determining the action time of the first protection device, the second protection device and the third protection device according to the inverse time limit current protection action curve equations of the first protection device, the second protection device and the third protection device;
s103: and performing inverse time-limited current protection on the multi-voltage-class power grid according to the respective action time of the first protection device, the second protection device and the third protection device.
In S101, the inverse time-lag current protection operation curve equation of the first protection device is determined according to equation (1):
wherein, t 1 Represents the operating time of the first protection device, I 1 Representing the measured current at the first protection device, I p Denotes the starting current, I p Taking 300A; k 1 Represents a voltage correction coefficient of the first protection device, and
U e1 indicating the rated voltage, U, of the first protection means e1 Is removable
U 1 Representing the measured voltage at the first protection device, m 1 Denotes the voltage margin of the first protection means, m 1 1.1 can be taken; a denotes a current parameter and r denotes a voltage parameter.
In S101, the inverse time-limited current protection operation curve equation of the second protection device is determined according to equation (2):
wherein, t 2 Indicating the time of operation of the second protection device, I 2 Indicating at a second protective deviceMeasuring current, K 2 Represents a voltage correction coefficient of the second protection device, and
U e2 indicating the rated voltage, U, of the second protection device e2 Is convenient to use
m 2 Denotes the voltage margin of the second protection means, m 2 1.1 can be taken; u' 2 Denotes the compensation voltage at the second protection device, and U' 2 ＝U 2 -I 2 ×kZ T ，U 2 Representing the measured voltage at the second protection device, Z T Represents the impedance of the transformer, k represents the compensation factor, and k may be 0.3.
In S101, the inverse time-limited current protection operation curve equation of the second protection device is determined according to equation (3):
wherein, t 3 Represents the operating time of the third protection device, I 3 Representing the measured current at the third protection device, K 3 A voltage correction coefficient of the third protection device, and
U e3 indicating the rated voltage of the third protection device, preferably
m 3 Denotes the voltage margin of the third protection means, m 3 1.1 can be taken; u shape 3 Representing the measured voltage at the third protection device.
In the step S101, the natural distribution of the grid voltage under the fault and the change rule of the measured voltage moving along with the fault position are utilized, and the inverse time-limited current protection action curve equations of the first protection device, the second protection device and the third protection device are modified through the respective voltage modification coefficients of the first protection device, the second protection device and the third protection device, so that the fault current decreases and the measured voltage increases as the distance between the fault point and the protection installation position increases, and compared with before modification, the action time of inverse time-limited current protection can be effectively improved, and the adaptability of the inverse time-limited current protection to the multi-voltage-class grid is enhanced.
In the above S102, the action time of each of the first protection device, the second protection device, and the third protection device is determined according to the inverse time-limited current protection action curve equation of each of the first protection device, the second protection device, and the third protection device, and the specific process is as follows:
1. determining a voltage parameter and a current parameter according to respective inverse time limit current protection action curve equations of the first protection device, the second protection device and the third protection device, wherein the specific process is as follows:
based on
And is
And obtaining A and r according to respective inverse time limit current protection action curve equations of the first protection device, the second protection device and the third protection device, wherein delta t 21 Representing the difference in level, Δ t, between the second protection device and the first protection device 32 Representing the step difference between the third protection device and the second protection device, at the end of the transmission line (i.e. point F in fig. 1) when a two-phase short-circuit fault occurs 21 And Δ t 32 The time can be 0.5 s;
2. and determining the action time of each of the first protection device, the second protection device and the third protection device according to the voltage parameter and the current parameter.
In the above step S103, inverse time-limited current protection is performed on the multi-voltage-class power grid according to the respective operation time of the first protection device, the second protection device, and the third protection device, and the specific process includes the following three cases:
1) if the tail end of the power transmission line fails, t passes 1 Then, firstThe protection device acts, and the second protection device and the third protection device do not act;
2) if the second bus fails, t passes 2 Then, the second protection device acts, and the first protection device and the third protection device do not act;
3) if the transformer fails, t is passed 3 Then, the third protection device is activated, and the first protection device and the second protection device are not activated.
On the other hand, the embodiment of the invention also provides an inverse time-limited current protection device for a multi-voltage-class power grid, wherein the structure diagram of the multi-voltage-class power grid is shown in fig. 1, and in fig. 1, G 1 Representing a first equivalent power supply, T representing a transformer, G 2 Representing a second, equal value source, B representing a first busbar, C representing a second busbar, D representing a third busbar, R 1 Denotes a first protective device, R 2 Denotes a second protective device, R 3 Indicating a third protection device and F a point of failure. In particular, the multi-voltage class grid comprises a first equivalent power source G 1 Transformer T and second equivalent power source G 2 First equivalent power source G 1 Connected with a transformer T through a first bus B, and the transformer T is connected with a second equivalent power supply G 2 The first protection device R is arranged on one side of the power transmission line close to the second bus C 1 A second protection device R is arranged on the line between the transformer T and the second bus C 2 A third protection device R is arranged on the line between the transformer T and the first bus B 3 The inverse time-limited current protection device for the multi-voltage-class power grid comprises a first determining module, a second determining module and a protection module, and the specific functions of the 3 modules are respectively described as follows:
the first determining module is used for determining inverse time limit current protection action curve equations of the first protection device, the second protection device and the third protection device respectively;
the second determining module is used for determining the action time of each of the first protection device, the second protection device and the third protection device according to the inverse time limit current protection action curve equation of each of the first protection device, the second protection device and the third protection device;
the protection module is used for carrying out inverse time limit current protection on the multi-voltage-class power grid according to the respective action time of the first protection device, the second protection device and the third protection device.
The first determining module comprises a first equation determining unit, and the first equation determining unit determines an inverse time limit current protection action curve equation of the first protection device according to the equation (1):
wherein, t 1 Represents the operating time of the first protection device, I 1 Representing the measured current at the first protection device, I p Denotes the starting current, K 1 Represents a voltage correction coefficient of the first protection device, and
U e1 indicating the rated voltage, U, of the first protection means 1 Representing the measured voltage at the first protection device, m 1 The voltage margin of the first protection device is indicated, a indicates a current parameter, and r indicates a voltage parameter.
The first determination module described above includes, in addition to the first equation determination unit, a second equation determination unit that determines an inverse time-limited current protection action curve equation of the second protection device according to equation (2):
wherein, t 2 Indicating the time of operation of the second protection device, I 2 Representing the measured current at the second protection device, K 2 Represents a voltage correction coefficient of the second protection device, and
U e2 indicating a second protective deviceNominal voltage of 2 Denotes a voltage margin, U 'of the second protection device' 2 Denotes the compensation voltage at the second protection device, and U' 2 ＝U 2 -I 2 ×kZ T ，U 2 Indicating the measured voltage at the second protection device, Z T Represents the impedance of the transformer and k represents the compensation factor.
The first determining module comprises a first equation determining unit and a second equation determining unit, and further comprises a third equation determining unit, wherein the third equation determining unit determines an inverse time limit current protection action curve equation of the second protection device according to the equation (3):
wherein, t 3 Represents the operating time of the third protection device, I 3 Representing the measured current at the third protection device, K 3 A voltage correction coefficient of the third protection device, and
U e3 denotes the rated voltage, m, of the third protective device 3 Indicating the voltage margin, U, of the third protection means 3 Representing the measured voltage at the third protection device.
The second determining module specifically includes:
1) the parameter determining unit determines a voltage parameter and a current parameter according to inverse time limit current protection action curve equations of the first protection device, the second protection device and the third protection device, and the specific process is as follows:
based on t 2 -t 1 ＝Δt 21 ，t 3 -t 2 ＝Δt 32 And obtaining A and r according to respective inverse time limit current protection action curve equations of the first protection device, the second protection device and the third protection device, wherein delta t 21 Representing the difference in level, Δ t, between the second and the first protection means 32 Representing a level difference between the third protection device and the second protection device;
2) and the time determining unit is used for determining the action time of each of the first protection device, the second protection device and the third protection device according to the voltage parameter and the current parameter.
The protection module carries out inverse time limit current protection on the multi-voltage-class power grid according to the respective action time of the first protection device, the second protection device and the third protection device, and the specific process comprises the following three conditions:
1) if the tail end of the power transmission line fails, t passes 1 Then, the first protection device acts, and the second protection device and the third protection device do not act;
2) if the second bus fails, t passes 2 Then, the second protection device acts, and the first protection device and the third protection device do not act;
3) if the transformer fails, t is passed 3 Then, the third protection device is activated, and the first protection device and the second protection device are not activated.
For convenience of description, each part of the above-described apparatus is separately described as being functionally divided into various modules or units. Of course, the functionality of the various modules or units may be implemented in the same one or more pieces of software or hardware when implementing the present application.
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.
Finally, it should be noted that: the above embodiments are only intended to illustrate the technical solution of the present invention and not to limit the same, and a person of ordinary skill in the art can make modifications or equivalents to the specific embodiments of the present invention with reference to the above embodiments, and such modifications or equivalents without departing from the spirit and scope of the present invention are within the scope of the claims of the present invention as set forth in the claims.
Claims (14)
1. The utility model provides a multi-voltage level electric wire netting inverse time limit current protection method, the multi-voltage level electric wire netting includes first equivalence power, transformer and second equivalence power, pass through first generating line connection between first equivalence power and the transformer, loop through second generating line, transmission line and third generating line connection between transformer and the second equivalence power, transmission line installs first protection device near second generating line one side, install the second protection device on the circuit between transformer and the second generating line, install the third protection device on the circuit between transformer and the first generating line, its characterized in that includes:
determining respective inverse time limit current protection action curve equations of the first protection device, the second protection device and the third protection device;
determining the action time of the first protection device, the second protection device and the third protection device according to the inverse time limit current protection action curve equation of the first protection device, the second protection device and the third protection device;
and performing inverse time-limited current protection on the multi-voltage-class power grid according to the respective action time of the first protection device, the second protection device and the third protection device.
2. The inverse-time-limited current protection method for the multi-voltage-class power grid according to claim 1, wherein the determining of the action time of each of the first protection device, the second protection device and the third protection device according to the inverse-time-limited current protection action curve equation of each of the first protection device, the second protection device and the third protection device comprises:
determining a voltage parameter and a current parameter according to respective inverse time limit current protection action curve equations of a first protection device, a second protection device and a third protection device;
and determining the action time of each of the first protection device, the second protection device and the third protection device according to the voltage parameter and the current parameter.
3. The inverse-time-limited current protection method for a multi-voltage-class power grid according to claim 2, wherein an inverse-time-limited current protection action curve equation of the first protection device is determined according to the formula (1):
wherein,t 1 represents the operating time of the first protection device, I 1 Representing the measured current at the first protection device, I p Denotes the starting current, K 1 Represents a voltage correction coefficient of the first protection device, and
U e1 indicating the rated voltage, U, of the first protection means 1 Representing the measured voltage at the first protection device, m 1 The voltage margin of the first protection device is indicated, a represents a current parameter, and r represents a voltage parameter.
4. The inverse-time-limited current protection method for multi-voltage-class power grid according to claim 3, wherein the inverse-time-limited current protection action curve equation of the second protection device is determined according to the formula (2):
wherein, t 2 Indicating the time of actuation of the second protection device, I 2 Representing the measured current at the second protection device, K 2 Represents a voltage correction coefficient of the second protection device, and
U e2 denotes the rated voltage, m, of the second protective device 2 Indicating the voltage margin, U, of the second protection means 2 ' denotes a compensation voltage at the second protection device, and U 2 ′＝U 2 -I 2 ×kZ T ，U 2 Representing the measured voltage at the second protection device, Z T Represents the impedance of the transformer and k represents the compensation factor.
5. The inverse-time-limit current protection method for the multi-voltage-class power grid according to claim 4, wherein an inverse-time-limit current protection action curve equation of the third protection device is determined according to equation (3):
wherein, t 3 Represents the operating time of the third protection device, I 3 Representing the measured current at the third protection device, K 3 A voltage correction coefficient of the third protection device, and
U e3 denotes the rated voltage, m, of the third protective device 3 Indicating the voltage margin, U, of the third protection means 3 Representing the measured voltage at the third protection device.
6. The inverse-time-limited current protection method for the multi-voltage-class power grid according to claim 5, wherein the determining of the voltage parameter and the current parameter according to the inverse-time-limited current protection action curve equation of each of the first protection device, the second protection device and the third protection device comprises:
based on t 2 -t 1 ＝Δt 21 ，t 3 -t 2 ＝Δt 32 And obtaining A and r according to respective inverse time limit current protection action curve equations of the first protection device, the second protection device and the third protection device, wherein delta t 21 Representing the difference in level, Δ t, between the second and the first protection means 32 Indicating the level difference between the third protection device and the second protection device.
7. The multi-voltage class power grid inverse-time-limit current protection method according to claim 5 or 6, wherein the inverse-time-limit current protection of the multi-voltage class power grid according to the respective action time of the first protection device, the second protection device and the third protection device comprises the following steps:
if the tail end of the transmission line fails, t is passed 1 Then, the first protection device acts, and the second protection device and the third protection device do not act;
if the second bus fails, t passes 2 Then, the second protection device acts, and the first protection device and the third protection device do not act;
if the transformer fails, t passes 3 Then, the third protection device is activated, and the first protection device and the second protection device are deactivated.
8. The utility model provides a multi-voltage level electric wire netting inverse time limit current protection device, multi-voltage level electric wire netting includes first equivalence power, transformer and second equivalence power, be connected through first generating line between first equivalence power and the transformer, loop through second generating line, transmission line and third generating line between transformer and the second equivalence power and be connected, transmission line installs first protection device near second generating line one side, install the second protection device on the circuit between transformer and the second generating line, install the third protection device on the circuit between transformer and the first generating line, its characterized in that includes:
the first determining module is used for determining the inverse time limit current protection action curve equations of the first protection device, the second protection device and the third protection device respectively;
the second determining module is used for determining the action time of the first protection device, the second protection device and the third protection device according to the inverse time limit current protection action curve equation of the first protection device, the second protection device and the third protection device;
and the protection module is used for carrying out inverse time limit current protection on the multi-voltage-class power grid according to the action time of each of the first protection device, the second protection device and the third protection device.
9. The multi-voltage class grid inverse-time-limited current protection device according to claim 8, wherein the second determining module comprises:
the parameter determining unit is used for determining a voltage parameter and a current parameter according to the inverse time limit current protection action curve equations of the first protection device, the second protection device and the third protection device;
and the time determining unit is used for determining the action time of each of the first protection device, the second protection device and the third protection device according to the voltage parameter and the current parameter.
10. The multi-voltage-class grid inverse-time-current protection device according to claim 9, wherein the first determination module comprises a first equation determination unit that determines an inverse-time-current protection action curve equation of the first protection device according to equation (1):
wherein, t 1 Represents the operating time of the first protection device, I 1 Representing the measured current at the first protection device, I p Denotes the starting current, K 1 Represents a voltage correction coefficient of the first protection device, and
U e1 indicating the rated voltage, U, of the first protection means 1 Representing the measured voltage at the first protection device, m 1 The voltage margin of the first protection device is indicated, a indicates a current parameter, and r indicates a voltage parameter.
11. The multi-voltage class grid inverse-time-current protection device according to claim 10, wherein the first determination module further comprises a second equation determination unit that determines an inverse-time-current protection action curve equation of the second protection device according to equation (2):
wherein, t 2 Indicating the time of operation of the second protection device, I 2 Indicating a second protection deviceMeasured current of, K 2 Represents a voltage correction coefficient of the second protection device, and
U e2 denotes the rated voltage, m, of the second protective device 2 Indicating the voltage margin, U, of the second protection means 2 ' denotes a compensation voltage at the second protection device, and U 2 ′＝U 2 -I 2 ×kZ T ，U 2 Representing the measured voltage at the second protection device, Z T Represents the impedance of the transformer and k represents the compensation factor.
12. The inverse-time-limit current protection device for a multi-voltage-class power grid according to claim 11, wherein the first determining module comprises a third equation determining unit, and the third equation determining unit determines an inverse-time-limit current protection action curve equation of the third protection device according to equation (3):
wherein, t 3 Represents the operating time of the third protection device, I 3 Representing the measured current at the third protection device, K 3 A voltage correction coefficient of the third protection device is expressed, and
U e3 denotes the rated voltage, m, of the third protective device 3 Indicating the voltage margin, U, of the third protection means 3 Representing the measured voltage at the third protection device.
13. The multi-voltage-class power grid inverse-time-limited current protection device according to claim 10, wherein the parameter determination unit is specifically configured to:
based on t 2 -t 1 ＝Δt 21 ，t 3 -t 2 ＝Δt 32 And is combined withObtaining A and r according to respective inverse time limit current protection action curve equations of the first protection device, the second protection device and the third protection device, wherein delta t 21 Representing the difference in level, Δ t, between the second and the first protection means 32 Indicating the level difference between the third protection device and the second protection device.
14. The multi-voltage-class power grid inverse-time-limit current protection device according to claim 12 or 13, wherein the protection module is specifically configured to:
if the tail end of the power transmission line fails, t passes 1 Then, the first protection device acts, and the second protection device and the third protection device do not act;
if the second bus fails, t passes 2 Then, the second protection device acts, and the first protection device and the third protection device do not act;
if the transformer fails, t passes 3 Then, the third protection device is activated, and the first protection device and the second protection device are not activated.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711232504.6A CN108092242B (en) | 2017-11-30 | 2017-11-30 | Multi-voltage-level power grid inverse time-limit current protection method and device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711232504.6A CN108092242B (en) | 2017-11-30 | 2017-11-30 | Multi-voltage-level power grid inverse time-limit current protection method and device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108092242A CN108092242A (en) | 2018-05-29 |
| CN108092242B true CN108092242B (en) | 2022-09-20 |
Family
ID=62173352
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711232504.6A Active CN108092242B (en) | 2017-11-30 | 2017-11-30 | Multi-voltage-level power grid inverse time-limit current protection method and device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108092242B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110333422B (en) * | 2019-06-17 | 2022-06-07 | 国网上海市电力公司 | Fault indicator ground fault judgment method for inverse time limit characteristics of relay protection device |
| CN110739669B (en) * | 2019-10-30 | 2021-06-29 | 三峡大学 | Inverse time limit overcurrent protection method based on impedance correction |
| CN111740379B (en) * | 2020-07-01 | 2022-09-30 | 北京四方继保自动化股份有限公司 | Method for automatically adjusting zero sequence protection two-segment and three-segment time constant values on line |
| CN113725829B (en) * | 2021-07-22 | 2022-06-28 | 西安交通大学 | Power distribution network backup protection method and system with automatic matching relationship |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4642724A (en) * | 1982-06-22 | 1987-02-10 | S&C Electric Company | Trip signal generator for a circuit interrupter |
| JP2010067514A (en) * | 2008-09-11 | 2010-03-25 | Mitsubishi Electric Corp | Circuit breaker unit |
| CN201440569U (en) * | 2009-04-28 | 2010-04-21 | 北京中煤电气有限公司 | Multi-voltage power supply whole-set device |
| CN102255294A (en) * | 2011-07-26 | 2011-11-23 | 天津大学 | Voltage acceleration inverse time-delay over-current protection method used for micro power grid |
| CN103094888A (en) * | 2013-01-08 | 2013-05-08 | 华北电力大学（保定） | Matching method of complex distribution network over-current protection timing sequence based on novel directional element |
| CN103840424A (en) * | 2014-03-20 | 2014-06-04 | 国家电网公司 | Automatic constant value setting microcomputer-based line protection implementation method |
-
2017
- 2017-11-30 CN CN201711232504.6A patent/CN108092242B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4642724A (en) * | 1982-06-22 | 1987-02-10 | S&C Electric Company | Trip signal generator for a circuit interrupter |
| JP2010067514A (en) * | 2008-09-11 | 2010-03-25 | Mitsubishi Electric Corp | Circuit breaker unit |
| CN201440569U (en) * | 2009-04-28 | 2010-04-21 | 北京中煤电气有限公司 | Multi-voltage power supply whole-set device |
| CN102255294A (en) * | 2011-07-26 | 2011-11-23 | 天津大学 | Voltage acceleration inverse time-delay over-current protection method used for micro power grid |
| CN103094888A (en) * | 2013-01-08 | 2013-05-08 | 华北电力大学（保定） | Matching method of complex distribution network over-current protection timing sequence based on novel directional element |
| CN103840424A (en) * | 2014-03-20 | 2014-06-04 | 国家电网公司 | Automatic constant value setting microcomputer-based line protection implementation method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108092242A (en) | 2018-05-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108092242B (en) | Multi-voltage-level power grid inverse time-limit current protection method and device | |
| CN108199349B (en) | Series transformer valve side winding turn-to-turn zero sequence differential protection method and device | |
| CN103278711B (en) | The early detection of a kind of short trouble and series arc faults and discrimination method | |
| CN106711968B (en) | Setting method and system for inverse time limit zero sequence current protection | |
| KR101438041B1 (en) | Control circuit for electric power circuit switch | |
| CN105140893A (en) | Differential protection current transformer (CT) saturation recognition method | |
| CN110571769B (en) | Differential protection method and device for power transmission line | |
| CN109617029B (en) | Power grid protection method and system based on harmonic protection device | |
| CN109193705B (en) | Method and device for inhibiting subsynchronous resonance of doubly-fed wind turbine generator | |
| CN103795074B (en) | According to the method that current phase angle and range-adjusting transmission line wire phase sequence arrange | |
| CN116632770B (en) | Series resonance judgment and suppression method and device for automatic tracking compensation arc suppression coil | |
| CN108539716B (en) | A kind of protection starting method and apparatus based on transient | |
| CN103633660B (en) | A kind of segmented suppresses the method for AC overvoltage and overfrequency | |
| CN107968384B (en) | Same-pole multi-loop zero-sequence current protection method and device | |
| CN107994550B (en) | Coordination method and system for current collection line protection and fan box transformer fuse | |
| CN109038471B (en) | Intelligent switch controller quick tripping algorithm based on curve fitting | |
| Le Blond et al. | High frequency protection scheme for multi-terminal HVDC overhead lines | |
| CN110289625B (en) | Regional power grid switching method and device | |
| CN110940890A (en) | Method and device for positioning series grounding fault of power distribution network | |
| Wang et al. | Long transmission lines fault location based on parameter identification using one-terminal data | |
| CN111049111A (en) | Sectional type fault protection criterion method for active distribution line | |
| CN110867828B (en) | Method and device for positioning turn-to-turn fault of energy-pumping reactor | |
| CN103762573A (en) | Self-adaptive zero-sequence current protecting method for electric transmission line | |
| CN110580366A (en) | Method and device for optimizing electrical parameters of current-limiting reactor of direct-current power grid | |
| CN109521358B (en) | Impedance matching calculation method and system for protection device outlet relay circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |