CN113809771A - Black-start subsystem parallel method taking recovery time and success rate into overall consideration - Google Patents
Black-start subsystem parallel method taking recovery time and success rate into overall consideration Download PDFInfo
- Publication number
- CN113809771A CN113809771A CN202111027079.3A CN202111027079A CN113809771A CN 113809771 A CN113809771 A CN 113809771A CN 202111027079 A CN202111027079 A CN 202111027079A CN 113809771 A CN113809771 A CN 113809771A
- Authority
- CN
- China
- Prior art keywords
- parallel
- black
- subsystem
- sides
- point
- 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.)
- Granted
Links
- 241001672018 Cercomela melanura Species 0.000 title claims abstract description 73
- 238000000034 method Methods 0.000 title claims abstract description 42
- 238000011084 recovery Methods 0.000 title claims abstract description 32
- 238000005192 partition Methods 0.000 claims abstract description 72
- 230000008569 process Effects 0.000 claims description 11
- 230000001360 synchronised effect Effects 0.000 claims description 8
- 230000009471 action Effects 0.000 claims description 7
- 239000003990 capacitor Substances 0.000 claims description 3
- 238000012544 monitoring process Methods 0.000 claims description 3
- 238000010586 diagram Methods 0.000 description 4
- 238000010276 construction Methods 0.000 description 2
- 230000000087 stabilizing effect Effects 0.000 description 2
- 238000004804 winding Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007123 defense Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 230000009191 jumping Effects 0.000 description 1
- 235000020281 long black Nutrition 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/24—Arrangements for preventing or reducing oscillations of power in networks
- H02J3/241—The oscillation concerning frequency
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Supply And Distribution Of Alternating Current (AREA)
Abstract
A black-start subsystem parallel method taking recovery time and success rate into overall consideration comprises the following steps: calculating the time required for recovering each subsystem from the black start power supply to each parallel point according to the black start subsystem partition grid structure and the black start power supply position; searching out two adjacent subsystems which are firstly restored to the parallel point according to the calculated time; then, parallel points are selected based on the standards of small impulse voltage and large parallel point short-circuit capacity, the voltage difference of node voltages at two sides of the parallel points, the frequency difference of systems at two sides of the parallel points and the phase angle difference between the tail end of the circuit and the parallel points at the other side of the circuit after the circuit is switched on from one side with large short-circuit capacity are judged, and the circuit opposite side switch is switched after the limit value is met, so that the parallel connection of two adjacent subsystems is completed; and a new subsystem formed after the adjacent subsystems are collocated participates in subsequent juxtaposition until the system is completely recovered. The invention can greatly reduce the black start recovery time and also consider the black start success rate, and reduce the power failure loss caused by overlong black start time.
Description
Technical Field
The invention relates to a black start process of a power grid full stop after a serious fault of a power system, in particular to a black start subsystem parallel method taking recovery time and success rate into overall consideration.
Background
When a large-area power failure occurs to a regional power system due to an accident, the power grid is in a completely black state, and the power grid needs to be immediately subjected to black start in order to quickly recover load power supply, reduce economic loss and ensure social stability. The black start is the last defense line of the safe operation of the power system, and a reasonable black start scheme is formulated, so that the method has important significance for accelerating the recovery process after the system full black accident and reducing the accident loss.
In order to accelerate the recovery of the whole system, each level of scheduling should divide the power grid into a plurality of black-start subsystems which are recovered in parallel, and each subsystem can be recovered simultaneously. Each subsystem should determine a main grid, internal black-start power supply, main power plant, hub substation and critical loads. When the main framework in the subsystems is gradually constructed, the subsystems are considered to be parallel, and the impact current in the parallel process is not more than an allowable value and influences the stability of the system.
At present, the black start research focus focuses on automatic generation of a scheme and comprehensive evaluation of corresponding weights given to indexes such as scheme recovery time, operation times and recovery success rate, and the like, and is focused on the advantages and disadvantages of the whole black start scheme; but little research has been conducted on the parallel aspect of black start subsystems. However, too long black start time or subsystem parallel failure may result in a secondary crash or equipment damage to the subsystem with the established master shelf, which is unacceptable for vulnerable systems in full black post-recovery. Therefore, the research of a subsystem parallel method taking the black start success rate and the recovery time into consideration has important significance for improving the black start success rate and accelerating the whole network recovery process.
The invention provides a black-start subsystem parallel method taking recovery time and success rate into consideration comprehensively, aiming at improving the time consumption and the success rate of forming a complete system by parallel subsystems of established main network frames, shortening the power failure loss caused by overlong black-start process time of a power grid and playing an important role in national economy stability.
Disclosure of Invention
In view of the above, the invention provides a black-start subsystem parallel method taking recovery time and success rate into consideration, and the parallel process of subsystems is accelerated as much as possible on the premise of ensuring the parallel success rate of the subsystems. The method has important significance for accelerating the recovery speed of the power grid after the power grid is completely blacked, shortens the power failure loss and equipment damage caused by overlong black start time or black start failure of the power grid, and plays an important role in stabilizing national economy.
The invention is realized by adopting the following technical scheme:
a black start subsystem parallel method taking recovery time and success rate into overall consideration comprises the following steps: firstly, calculating the time required by each subsystem to recover from a black start power supply to each parallel point according to the partition grid structure of the black start subsystem and the position of the black start power supply; then searching out two adjacent subsystems which are firstly restored to the parallel point according to the calculated time; then, parallel points are selected based on the standards of small impulse voltage and large parallel point short-circuit capacity, the voltage difference of node voltages at two sides of the parallel points, the frequency difference of systems at two sides of the parallel points and the phase angle difference between the tail end of the circuit and the parallel points at the other side of the circuit after the circuit is switched on from one side with large short-circuit capacity are judged, and the circuit opposite side switch is switched after the limit value is met, so that the parallel connection of two adjacent subsystems is completed; and finally, a new subsystem formed after the adjacent subsystems are parallel participates in subsequent parallel operation until the system is completely recovered.
Further, the method comprises the following specific implementation steps:
step 1: firstly, calculating the time required for recovering each subsystem from the black start power supply to each parallel point according to the grid structure of each subsystem and the position of the black start power supply;
step 2: judging whether the number of the current subsystems is larger than 1, if so, turning to a step 3, and if not, turning to a step 12;
and step 3: searching two adjacent subsystems which are recovered to a parallel point most quickly according to the time calculated in the step 1;
and 4, step 4: judging whether only one point capable of being paralleled exists at present, if so, turning to the step 6, and if not, turning to the step 5;
and 5: selecting an optimal parallelable point according to the line length and the short circuit capacity of the parallelable point;
step 6: judging whether the voltage difference of the node voltages at two sides of the parallel points meets a limiting value, namely delta U is less than 0.2p.u, if so, turning to a step 8, and if not, turning to a step 7;
and 7: adjusting the voltage difference of the node voltages at two sides of the parallel points to meet a limiting value;
and 8: judging whether the frequency difference of the systems at two sides of the parallel points meets a limit value, namely 0.1< DELTAf <0.5Hz, if so, turning to the step 10, and if not, turning to the step 9;
and step 9: increasing the unit output or adjusting the load until the frequency difference of the systems at the two sides of the parallel point meets the limit value;
step 10: switching on the line from one side with large short-circuit capacity, monitoring phase angle difference at two sides of a parallel point by adopting a synchronous device to be as close to 0 degree as possible, and then switching on the opposite side of the line to complete the parallel connection of the two subsystems;
step 11: a new subsystem is formed to continue participating in the subsequent parallel process;
step 12: the system is fully recovered.
Further, step 1 specifically includes: and setting all the nodes of the same station and the same voltage grade in each independent node, taking the nodes of the same station and different voltage grades as another node, setting the time from one node to the other node as a constant value T, enabling each node to reach several different nodes of the next stage at the same time, and calculating the total time required by any node in the black-start power supply recovery subsystem, namely the time required by each subsystem to recover from the black-start power supply to each parallel point.
Further, the pressure difference of the systems at two sides of the parallel point in the step 6 must meet the instantaneous maximum value of the impact current at the closing moment
Should not make the current of the line near the parallel point quickly break protection action, in the formula, U1And U2Respectively, the voltage, X, across the parallel points1And X2Respectively, the equivalent impedances looking into the system from the parallel points.
Furthermore, in step 8, considering that the closing phase angle must be smaller than the maximum allowable error phase angle within the error time of the breaker action, the maximum value of the frequency difference of the systems at two sides of the parallel point should be equal to
Meanwhile, in order to capture the closing opportunity quickly, the minimum value of the frequency difference should meet the requirement
Considering typical parameters of the current circuit breaker, the frequency difference value range is preferably 0.1-0.5 Hz, wherein: deltaeyMaximum allowable error phase angle, Δ t, that must be satisfied for the closing phase anglecAnd Δ tQFRespectively are the error time of the closing of the synchronizing device and the breaker.
Further, in step 10, the phase angle difference between the systems at the two sides of the parallel point should satisfy the instantaneous maximum value of the impact current at the moment of closing
The current quick-break protection action of the line near the parallel point is not required; in order to ensure that the impact current is as small as possible, the parallel points should select a line connected to a synchronous device, and automatically capture parallel time, so that the phase angle difference of the parallel time is close to 0 DEG, wherein: u is the electromotive force of parallel points, X1And X2Respectively, the equivalent impedance, delta, looking into the system from the parallel points0Is the phase angle difference between the two sides of the parallel point.
Further, in step 7, a reactor or a capacitor is used to adjust the voltage difference of the node voltages at the two sides of the parallel point.
Further, in step 6, it is determined whether the voltage difference between the node voltages at the two sides of the parallel point satisfies the limit value, i.e. it is determined that Δ U is less than 0.2 p.u.
Further, in step 8, it is determined whether the frequency difference between the systems on both sides of the parallel point satisfies the limit value, that is, it is determined that 0.1Hz <. DELTA.f <0.5 Hz.
The invention has the advantages that:
1. compared with the prior black start scheme which generally adopts a system with larger installed capacity and a subsystem with smaller installed capacity in parallel, the method considers that the system with small installed capacity is small in scale and the main framework is high in construction speed, and adopts a strategy that adjacent subsystems which are restored to parallel points firstly are preferentially parallel, so that the time for restoring the whole network is reduced;
2. according to the invention, while the black start recovery rate is improved, factors such as pressure difference, frequency difference and phase angle difference are considered comprehensively, and a unit needs to be started for supporting when a parallel point is far away from a black start power supply, so that the impact current in the parallel process is ensured to be small, the frequency difference of systems on two sides is small, the two subsystems after switching on can quickly enter a synchronous transient process, and the parallel success rate of the black start is improved;
3. the invention provides an optimization strategy for a power grid dispatching operation mechanism to recover the whole power grid after the power grid is totally black, is beneficial to reducing the operation risk of a large power grid, and has important social and economic stability.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and those skilled in the art can also obtain other drawings according to the drawings without creative efforts.
FIG. 1 is a flow diagram of one embodiment of a black start subsystem parallelization method that orchestrates the consideration of recovery time and success rate;
FIG. 2 is a schematic diagram of Huazhong power grid black start partitions and parallel points;
fig. 3 is a sequence diagram of parallel operations of the Huazhong power grid overall considering recovery time and success rate.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.
The embodiment of the invention provides a black-start subsystem parallel method taking recovery time and success rate into overall consideration, which comprises the following steps: firstly, calculating the time required by each subsystem to recover from a black start power supply to each parallel point according to the partition grid structure of the black start subsystem and the position of the black start power supply; then searching out two adjacent subsystems which are firstly restored to the parallel point according to the calculated time; then, judging the voltage difference of node voltages at two sides of the parallel point, the frequency difference of systems at two sides of the parallel point and the phase angle difference between the tail end of the circuit and the parallel point at the other side after the circuit is closed from one side with large short circuit capacity, and connecting a circuit opposite side switch after the limit value is met to complete the parallel connection of the two subsystems; and the finally formed new subsystem participates in the subsequent parallel operation until the system is completely recovered.
Referring to fig. 1, the specific implementation steps include:
step 1: firstly, the time required for recovering each subsystem from the black start power supply to each parallel point is calculated according to the grid structure of each subsystem and the position of the black start power supply.
Specifically, each independent node is set to include all nodes of the same station and the same voltage level, the station and the voltage level are regarded as another node, the time from one node to another node is a constant value T, each node reaches different nodes of the next level at the same time, and the total time required by any node in the black-start power recovery subsystem is calculated.
When time is calculated, the end winding of the generator is easy to generate heat or the generator generates self-excitation due to impact current when the parallel point is switched on, and generally, a line with power plants on two sides is not selected as the parallel point. When the time is calculated, if the parallel point is far away from the black start power supply, the units near the parallel point are started first and then parallel.
Step 2: judging whether the number of the current subsystems is larger than 1, if so, turning to a step 3, and if not, turning to a step 12;
and step 3: searching two adjacent subsystems which are recovered to a parallel point most quickly according to the time calculated in the step 1;
and 4, step 4: judging whether only one point capable of being paralleled exists at present, if so, turning to the step 6, and if not, turning to the step 5;
and 5: selecting an optimal parallelable point according to the line length and the short circuit capacity of the parallelable point;
step 6; judging whether the voltage difference of the node voltages at two sides of the parallel points meets a limiting value, for example, delta U is less than 0.2p.u, if so, turning to a step 8, and if not, turning to a step 7;
in the step 6, the pressure difference of the systems at two sides of the parallel point must meet the instantaneous maximum value of the impact current at the closing moment
The current quick-break protection operation of the line near the parallel point should not be performed. Generally, the voltage difference between the two sides of the parallel points should not exceed 20%, and the voltage on the first closing side of the first parallel point should be lower than the voltage on the second closing side. In the formula of U1And U2Respectively, the voltage, X, across the parallel points1And X2Respectively, the equivalent impedances looking into the system from the parallel points.
And 7: adopting modes of reactor and capacitor to regulate the voltage difference of node voltages at two sides of parallel points to meet the limit value;
and 8: judging whether the frequency difference of the systems at two sides of the parallel point meets a limit value, for example, 0.1< DELTAf <0.5Hz, if so, turning to the step 10, and if not, turning to the step 9;
in step 8, considering that the closing phase angle must be smaller than the maximum allowable error phase angle within the error time of the breaker action, the maximum value of the frequency difference of the systems at two sides of the parallel point should be equal to
Simultaneously: in order to capture the closing time quickly, the minimum frequency difference value should also satisfy
Considering typical parameters of the current circuit breaker, the frequency difference value range is preferably 0.1-0.5 Hz. In the formula: deltaeyMaximum allowable error phase angle, Δ t, that must be satisfied for the closing phase anglecAnd Δ tQFThe error time of closing the synchronous device and the breaker.
And step 9: increasing the output of the unit or adjusting the load until the frequency difference of the systems at the two sides of the parallel point meets the limit value;
step 10: switching on the line from one side with large short-circuit capacity, monitoring phase angle difference at two sides of a parallel point by adopting a synchronous device to be as close to 0 degree as possible, and then switching on the opposite side of the line to complete the parallel connection of the two subsystems;
in step 10, the phase angle difference between the systems at the two sides of the parallel point should satisfy the requirement of the instantaneous maximum value of the impact current at the closing moment
The current quick-break protection operation of the line near the parallel point should not be performed. In order to ensure that the impact current is as small as possible, the parallel points should select a line connected to a synchronous device, and automatically capture parallel time, so that the phase angle difference of the parallel time is close to 0 degree. In the formula: u is the electromotive force of parallel points, X1And X2Respectively, the equivalent impedance, delta, looking into the system from the parallel points0Is the phase angle difference between the two sides of the parallel point.
Step 11: a new subsystem is formed to continue participating in the subsequent parallel process;
step 12: the system is fully recovered.
The above steps are described in detail in the examples.
By taking a certain black start partition scheme of the power grid in China as an example, the method is applied to research subsystem parallel strategies, and plays an important role in ensuring that the black start success rate is shortened and the power failure loss caused by overlong black start process time of the power grid is reduced, and in stabilizing national economy.
The implementation process of the method comprises the following steps:
step 1 in fig. 1 is executed first, and the time required for the black start power supply in each partition to recover to the parallel point is calculated for the Huazhong power grid partition diagram shown in fig. 2 (as shown in table 1). Wherein the parallel point of C1-C2 is a 220kV standby connecting line, generally, because the 220kV lines are more, the 500kV main line is not considered to be started from 220 kV.
Since the impulse current at the closing of the parallel points is likely to cause the end winding of the generator to generate heat or the generator to generate self-excitation, the lines with power plants on both sides are generally not selected as the parallel points. When the time is calculated, if the parallel point is far away from the black start power supply, the unit near the parallel point is started first, and then parallel operation is performed.
TABLE 1
Considering that the oscillation of the system occurs in two partitions in parallel and is in an unstable state, the same subsystem only performs parallel operation at the parallel point in the same time window T and is not parallel to other two subsystems simultaneously.
According to the mainstream recovery method for grid connection in the Huazhong power grid according to the system with large capacity, because the number of lines in the subsystem with large capacity is large, the recovery is required to be started from 4T, and only one subsystem can be connected to the grid at one time, and for 14 subsystem branch Huazhong power grids, the time for completing the construction of a main grid is 17T. The method has the advantages that the stability of the net rack is high, but the time consumption is too long, and the method is not favorable for the social and economic stability of the blackish power grid.
The order of parallel operation of Huazhong power grid overall consideration of recovery time and success rate is as follows, and the flow chart is shown in FIG. 3:
step 2 in fig. 1 is executed, and the number of subsystems is judged to be greater than 1.
2T: executing steps 3-9 in the figure, forming a partition 15 by juxtaposing the partition 8 and the partition 9 through B36-B35, and returning to step 2;
3T: steps 3-9 of the figure are performed, partition 15 may be juxtaposed with partitions 7, 11, and partition 10 may be juxtaposed with partition 11. Considering that more subsystems participate in parallel connection in the same time period, the line length and the short-circuit capacity, the subarea 15 and the subarea 7 are connected in parallel through B28-B29 to form a subarea 16, the subarea 10 and the subarea 11 are connected in parallel through B37-B39 to form a subarea 17, and the step 2 is returned;
4T: in steps 3-9 of the figure, partition 1 may be collocated with partition 2, partition 2 may be collocated with partition 3, partition 3 may be collocated with partition 4, partition 4 may be collocated with partition 6, and partition 16 may be collocated with partition 17. Partition 12 may be juxtaposed with partition 13; partition 13 may be juxtaposed with partition 17; partition 14 may be juxtaposed with partition 16. Considering that more subsystems participate in parallel connection in the same time period, the line length and the short-circuit capacity, the partition 1 and the partition 2 are connected in parallel through B1-B2 to form a partition 18, and the partition 3 and the partition 4 are connected in parallel through B13-B24 to form a partition 19; partition 16 and partition 17 are juxtaposed to form partition 20 by B31-B32; the partition 12 and the partition 13 are parallelly formed into a partition 21 through B45-B52, and the step 2 is returned;
5T: in steps 3-9 of the figure, partition 6 may be juxtaposed with partitions 19, 20, and partition 20 may be juxtaposed with partition 21. Overall consideration should be given to the fact that more subsystems participate in the parallel connection in the same time period, and the line length and short circuit capacity, partition 6 and partition 19 are connected in parallel through B16-B17 to form partition 22, and partition 20 and partition 21 are connected in parallel through B41-B42 to form partition 23. At this time, partitions 18, 22, 23 and 5 are arranged in the system, and the step 2 is returned;
6T: steps 3-9 of the figure are performed, partition 18 may be aligned with partition 22, and partition 22 may be aligned with partition 23. Considering the line length and the short-circuit capacity, the subarea 22 and the subarea 23 form a subarea 24 in parallel through B26-B27 or B23-B29, and the step 2 is returned;
7T: executing steps 3-9 in the figure, and enabling the partition 24 and the partition 18 to be juxtaposed to form a partition 25 through B5-B6, and returning to step 2; .
8T: executing steps 3-9 in the figure, forming a partition 26 by juxtaposing the partition 25 and the partition 5 through B20-B21, and returning to step 2; .
9T: and (3) executing the steps 3-9 in the figure, connecting the subareas 26 and 14 in a grid mode, returning to the step 2, judging that the number of the subsystems is 1, completely connecting the main racks of the system in parallel, and jumping out of the parallel flow of the subsystems.
In the parallel flow of fig. 1, the grid-connected condition with the partition 6 is already met due to the simple framework in the partition 5, but the parallel points B20-B21 are far from the black-start power supply in the partition 6, so that the partition 5 cannot be incorporated into the main grid at a later time. Therefore, after recovery in the partition 5 is finished, the station in the partition 6 is recovered directly through two parallel columns of B20-B21 and B19-B22, and at 4T, the partitions 5 and 6 can be directly connected to the grid. At this time, the system main framework rebuilds the total time of 8T.
By adopting the subsystem parallel method taking the recovery time and the success rate into overall consideration, the parallel success rate of the subsystems is considered, meanwhile, the time for reconstructing the net rack is increased from 17T to 8T, and the time for reconstructing the main network is saved by more than half.
The invention avoids the current mainstream method of starting the first parallel by adopting a subsystem with larger capacity, can greatly reduce the black start recovery time and give consideration to the black start success rate, reduces the power failure loss caused by overlong black start time, and has important significance for national social economy stability after the power grid is completely black.
The above description is only an embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (9)
1. A black-start subsystem parallel method taking recovery time and success rate into overall consideration is characterized by comprising the following steps: firstly, calculating the time required by each subsystem to recover from a black start power supply to each parallel point according to the partition grid structure of the black start subsystem and the position of the black start power supply; then searching out two adjacent subsystems which are firstly restored to the parallel point according to the calculated time; then, parallel points are selected based on the standards of small impulse voltage and large parallel point short-circuit capacity, the voltage difference of node voltages at two sides of the parallel points, the frequency difference of systems at two sides of the parallel points and the phase angle difference between the tail end of the circuit and the parallel points at the other side of the circuit after the circuit is switched on from one side with large short-circuit capacity are judged, and the circuit opposite side switch is switched after the limit value is met, so that the parallel connection of two adjacent subsystems is completed; and finally, a new subsystem formed after the adjacent subsystems are parallel participates in subsequent parallel operation until the system is completely recovered.
2. The black promoter system parallelization method for comprehensively considering the recovery time and the success rate according to claim 1, comprising the following steps:
step 1: firstly, calculating the time required for recovering each subsystem from the black start power supply to each parallel point according to the grid structure of each subsystem and the position of the black start power supply;
step 2: judging whether the number of the current subsystems is larger than 1, if so, turning to a step 3, and if not, turning to a step 12;
and step 3: searching two adjacent subsystems which are recovered to a parallel point most quickly according to the time calculated in the step 1;
and 4, step 4: judging whether only one point capable of being paralleled exists at present, if so, turning to the step 6, and if not, turning to the step 5;
and 5: selecting an optimal parallelable point according to the line length and the short circuit capacity of the parallelable point;
step 6: judging whether the voltage difference of the node voltages at two sides of the parallel points meets a limiting value, namely delta U is less than 0.2p.u, if so, turning to a step 8, and if not, turning to a step 7;
and 7: adjusting the voltage difference of the node voltages at two sides of the parallel points to meet a limiting value;
and 8: judging whether the frequency difference of the systems at two sides of the parallel points meets a limit value, namely 0.1< DELTAf <0.5Hz, if so, turning to the step 10, and if not, turning to the step 9;
and step 9: increasing the unit output or adjusting the load until the frequency difference of the systems at the two sides of the parallel point meets the limit value;
step 10: switching on the line from one side with large short-circuit capacity, monitoring phase angle difference at two sides of a parallel point by adopting a synchronous device to be as close to 0 degree as possible, and then switching on the opposite side of the line to complete the parallel connection of the two subsystems;
step 11: a new subsystem is formed to continue participating in the subsequent parallel process;
step 12: the system is fully recovered.
3. The black-start subsystem parallelization method for orchestrating recovery time and success rate as recited in claim 2, wherein: the step 1 specifically comprises the following steps: and setting all the nodes of the same station and the same voltage grade in each independent node, taking the nodes of the same station and different voltage grades as another node, setting the time from one node to the other node as a constant value T, enabling each node to reach several different nodes of the next stage at the same time, and calculating the total time required by any node in the black-start power supply recovery subsystem, namely the time required by each subsystem to recover from the black-start power supply to each parallel point.
4. A method as claimed in claim 2The quick search method for the initial starting path of the black start of the power grid is characterized by comprising the following steps of: in the step 6, the pressure difference of the systems at two sides of the parallel point must meet the instantaneous maximum value of the impact current at the closing moment
Should not make the current of the line near the parallel point quickly break protection action, in the formula, U1And U2Respectively, the voltage, X, across the parallel points1And X2Respectively, the equivalent impedances looking into the system from the parallel points.
5. The fast search method for the black start initial start path of the power grid according to claim 2, wherein: in step 8, considering that the closing phase angle must be smaller than the maximum allowable error phase angle within the error time of the breaker action, the maximum value of the frequency difference of the systems at two sides of the parallel point should be equal to
Meanwhile, in order to capture the closing opportunity quickly, the minimum value of the frequency difference should meet the requirement
Considering typical parameters of the current circuit breaker, the frequency difference value range is preferably 0.1-0.5 Hz, wherein: deltaeyMaximum allowable error phase angle, Δ t, that must be satisfied for the closing phase anglecAnd Δ tQFRespectively are the error time of the closing of the synchronizing device and the breaker.
6. The fast search method for the black start initial start path of the power grid according to claim 2, wherein: in step 10, the phase angle difference between the systems at the two sides of the parallel point should satisfy the instantaneous maximum value of the impact current at the moment of closing
The current quick-break protection action of the line near the parallel point is not required; in order to ensure that the rush current is as small as possible,the parallel point should select the line connected to the synchronous device, automatically capture the parallel time, and make the phase angle difference of the parallel time close to 0 degree, in the formula: u is the electromotive force of parallel points, X1And X2Respectively, the equivalent impedance, delta, looking into the system from the parallel points0Is the phase angle difference between the two sides of the parallel point.
7. The fast search method for the black start initial start path of the power grid according to claim 1, wherein: and 7, adopting a mode of putting a reactor or a capacitor to adjust the voltage difference of the node voltages at two sides of the parallel point.
8. The fast search method for the black start initial start path of the power grid according to claim 1, wherein: and 6, judging whether the voltage difference of the node voltages at two sides of the parallel point meets a limit value, namely judging that delta U is less than 0.2 p.u.
9. The fast search method for the black start initial start path of the power grid according to claim 1, wherein: and 8, judging whether the frequency difference of the systems at two sides of the parallel point meets a limit value, namely judging that 0.1Hz < Deltafis less than 0.5 Hz.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111027079.3A CN113809771B (en) | 2021-09-02 | 2021-09-02 | Black-start subsystem parallel method comprehensively considering recovery time and success rate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111027079.3A CN113809771B (en) | 2021-09-02 | 2021-09-02 | Black-start subsystem parallel method comprehensively considering recovery time and success rate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113809771A true CN113809771A (en) | 2021-12-17 |
| CN113809771B CN113809771B (en) | 2023-11-10 |
Family
ID=78894616
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111027079.3A Active CN113809771B (en) | 2021-09-02 | 2021-09-02 | Black-start subsystem parallel method comprehensively considering recovery time and success rate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113809771B (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102035256A (en) * | 2010-11-26 | 2011-04-27 | 山东电力研究院 | Auxiliary decision method for recovering group multiattitude of power system |
| CN103248127A (en) * | 2013-05-23 | 2013-08-14 | 山东大学 | Multi-space-time navigating power system restoration decision support system and restoration decision method |
| CN103792924A (en) * | 2014-02-14 | 2014-05-14 | 暨南大学 | Black-start method for expansion of electric power system with micro-grids |
-
2021
- 2021-09-02 CN CN202111027079.3A patent/CN113809771B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102035256A (en) * | 2010-11-26 | 2011-04-27 | 山东电力研究院 | Auxiliary decision method for recovering group multiattitude of power system |
| CN103248127A (en) * | 2013-05-23 | 2013-08-14 | 山东大学 | Multi-space-time navigating power system restoration decision support system and restoration decision method |
| CN103792924A (en) * | 2014-02-14 | 2014-05-14 | 暨南大学 | Black-start method for expansion of electric power system with micro-grids |
Non-Patent Citations (2)
| Title |
|---|
| LI TONGGE 等: "The Research on Black Start Strategy of Distributed Photovoltaic-Battery Energy Storage Systems Based on Cluster Division", 《SUSTAINABLE POWER AND ENERGY CONFERENCE》, pages 337 - 342 * |
| 刘艳 等: "用于网架重构方案运行风险评估的线路投运模型", 《中国电机工程学报》, vol. 34, no. 7, pages 1124 - 1131 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113809771B (en) | 2023-11-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Islam et al. | Coordinated decentralized emergency voltage and reactive power control to prevent long-term voltage instability in a power system | |
| CN108988322B (en) | Microgrid operation strategy optimization method considering system time-varying property | |
| CN107910887B (en) | Black start method considering participation of high-voltage direct-current power transmission system | |
| CN109066753B (en) | Control method and system based on charge state of energy storage battery | |
| CN110676839A (en) | Method and system for evaluating reliability of alternating current-direct current hybrid power distribution network | |
| CN103746366A (en) | Electric power system recovery method based on node importance degree | |
| CN112085275B (en) | Cascading failure prediction method of electric power information physical system based on multiple time scales | |
| CN107612021B (en) | Regional spare power automatic switching control method suitable for large number of small power supplies to access local power grid | |
| CN106711925B (en) | self-adaptive three-phase reclosing lock for single loop outgoing line of wind power plant and method thereof | |
| Zhou et al. | A multi-level coordinated DC overcurrent suppression scheme for symmetrical bipolar MMC-HVDC integrated offshore wind farms | |
| CN107179688B (en) | Power system reliability analysis method considering Monte Carlo state sampling truncation | |
| CN113809771A (en) | Black-start subsystem parallel method taking recovery time and success rate into overall consideration | |
| Patil et al. | A novel protection scheme for DC microgrid with hierarchical control | |
| CN217388240U (en) | Black start system and power supply system of microgrid | |
| CN103532520A (en) | Reactive power compensation device control method for preventing large-scale chain offline of wind generation sets | |
| CN111934367A (en) | Active defense method for key area power grid in typhoon mode | |
| Aluthge et al. | Battery Energy Storage System to Improve Reliability Due to under Frequency Load Shedding | |
| CN113541132A (en) | Coordination stability control method used after transformation of alternating current and direct current power grid | |
| CN112234644A (en) | Method and system for controlling re-grid connection of photovoltaic grid-connected power generation system | |
| Deng et al. | Optimal defense strategy for AC/DC hybrid power grid cascading failures based on game theory and deep reinforcement learning | |
| CN111106622A (en) | Active power distribution network power supply recovery method based on RMPC | |
| Khezri et al. | An Intelligent Fuzzy Control Approach for a Back-Pressure Autonomous Industrial Microgrid | |
| CN115115220B (en) | New energy cascading failure risk assessment method and system for Direct Current (DC) transmitting end system | |
| CN112531777B (en) | Water-light complementary system emergency cutting machine control method based on equal-area rule | |
| Ma et al. | Renewable Energy Integrated HVDC Power System Modeling for Transient Frequency Stability Online Assessment |
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 |