Transformer substation full-stop and full-transfer model construction method based on distribution network main net rack

Abstract

The invention discloses a transformer substation full-stop and full-transfer model construction method based on a distribution network main network frame, and relates to the technical field of power grids. Compared with a previous transformer substation full-stop and full-transfer strategy, the problem of how to quickly, safely and reliably transfer the load to other transformer substations or power supplies is solved; on the basis of a distribution network main network frame model, a transformer substation to which a feeder belongs is taken as a unit, a transformer substation full-stop and full-transfer analysis model is built and generated through topology analysis, on the basis of an improved eagle optimization algorithm, full-stop and full-transfer of the transformer substation are quickly realized by taking operation cost reduction as a target, and under the condition that the transformer substation breaks down or emergencies, the operation efficiency is improved. The model can also quickly formulate a full-stop full-turn scheme, thereby improving the emergency response speed and processing capability, reducing the power failure time and range, and improving the power supply reliability.

Description

Technical Field

[0001] The present invention relates to the field of power grid technology, and in particular to a method for constructing a full stop and full rotation model of a substation based on a distribution network main grid. Background Art

[0002] The substation full shutdown and full transfer model is a specific model in power system simulation, which is used to analyze the impact and response strategies when all substations in the power grid are shut down at the same time or all loads are transferred. This model is usually used to evaluate the resilience and stability of the power grid, especially in the face of challenges that may arise when large-scale substations are shut down or loads are transferred. It is an important method for evaluating the grid structure and reliability of the distribution network. The research focus of the existing technology is on the construction of the topological model of the power grid, and the load transfer after the substation is completely shut down in the later stage is not considered. In addition, the dynamic changes of the substation can easily affect the later operation status of the power grid. Therefore, how to quickly, safely and reliably transfer the load to other substations or power sources has become a problem that needs to be solved urgently. In order to solve the above problems, the present invention proposes a method for constructing a full stop and full rotation model of a substation based on the main grid of a distribution network. Summary of the invention

[0003] The purpose of the present invention is to propose a method for constructing a full stop and full turn model of a substation based on a distribution network main grid to solve the problems raised in the background technology: How to transfer loads to other substations or power sources quickly, safely and reliably.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions: The method for constructing a full stop and full rotation model of a substation based on the main grid of the distribution network includes the following steps: S1: Collect the topological structure of the distribution network and the main network and the grid data related to the substation; S2: pre-process and analyze the data collected by S1 and use it to build a power grid model; S3: defines a total power outage state; S4: Formulate a full stop and full turn strategy; S5: Simulate a full power outage scenario and adjust the operating state of the power grid model accordingly to obtain a full power outage and full operation model of the substation; S6: Analyze and evaluate the response capability of the substation full stop and full rotation model.

[0005] Preferably, in said S2, a substation model and a main grid model are constructed; The substation model is constructed as follows: P 1= V 1 I 1 cosθ 1 P2= V 2 I 2 cosθ 2 p=P+jQ = V 1 I 1 * = V 2 I 2 * in, P 1. P 2 are the active power of the primary and secondary sides of the transformer respectively; V 1. V 2 is the corresponding voltage; I 1. I 2 is the current; i 1. i 2 is the power factor angle; p is the complex power; P is the transformer active power; Q is the reactive power; j is an imaginary number; I 1 * , I 2 * For current I 1. I plural form of 2; Compensation amount of reactive power compensation device Q c It is expressed as: Q c =CV 2 in, C is the capacitance value of the compensation capacitor; V is the bus voltage; The main network model is constructed as follows: P ij = U i 2 G ij -U i U j ( G ij cosθ ij +B ij sinth ij ) Q ij =-U i 2 B ij +U i U j ( G ij sinth ij -B ij cosθ ij ) in, P ij and Q ij Slave nodes i To Node j The active power and reactive power of U i and U j Is a node i and j The voltage amplitude, i ij Is a node i and j The voltage phase difference between G ij and B ij are the conductance and susceptance of the line respectively; Power balance constraints: Σ kϵL(i) P ik -P if = 0 Σ kϵL(i) Q ik -Q if = 0 Among them, L(i) is the node i The set of adjacent nodes; P if and Q if Is a node i Active and reactive loads; P ik and Q ik Slave nodes i To Node k Active power and reactive power; Voltage Constraints: U min ≤U i ≤U max in, U max and U min are the maximum and minimum values ​​of the node voltage respectively; Line capacity constraints: | S ij | ≤S max,ij in, S ij For slave nodes i To Node j The power transmitted by the line; S max,ij For slave nodes i To Node j The maximum permissible value of line transmission power; Logical constraints: The line input and substation operation status conform to the actual logic; At the same time, the load model is built as follows: P i = P i0 ( α P +β P U i +g P U i 2 ) Q i = Q i0 ( α Q +β Q U i +g Q U i 2 ) in, P i and Q i Node i Active and reactive loads;P i0 and Q i0 Node i Initial active and reactive loads; α P , β P , c P , α Q , β Q , c Q is the coefficient of the load model.

[0006] Preferably, in S3, the full power outage state is defined as follows: Defining decision variables x ij , indicating that from the substation i To the substation j Whether the line is put into use, x ij = 1 means investment, x ij = 0 means no investment.

[0007] Preferably, the full stop and full start strategy is formulated as follows: When the substation is completely shut down, the backup power supply is put into use, or the load supplied by the substation is transferred to the adjacent substation in proportion. The transfer ratio is determined based on the remaining capacity and load importance of each substation based on the improved Tianying optimization algorithm; the improved Tianying optimization algorithm is as follows: Taking minimizing power outage losses as the objective function H : H = minutes Σ i oh i f i t i + Σ i,j cost ij x ij in, oh i is the load point i Importance weight of f i is the load point i of power outage load; t i is the load point i The power outage time; cost ij Is the input line i arrive j Costs; The position of the eagle, that is, the initial value of the parameter value, is obtained by the following formula: X m =( dU m -dL m )× rand+dL m in, X m For the m The initial value of the parameter value; dU m and dL m For the m upper and lower limits for parameter values; rand is a random number between (0,1); At the iteration number t ≤ 2 T / At 3, the parameter values ​​are updated by predation mode 1 and mode 2; Tianying updates the parameter values ​​at the iteration number t > 2 T / At 3, the current parameter values ​​are updated by predation methods 3 and 4; Predation method 1: X 1,t+1 = X b,t ×( 1-t / T )+( X a,t -X b,t )× rand

[0008] in, X 1,t+1 For predation method 1 t+ Parameter values ​​updated in 1 iteration; X b,t is the current optimal parameter value; T is the maximum number of iterations; X a,t is the average value of the solution; M is the number of candidate values ​​for the parameter; X i,t Load point i No.t The parameter value updated in the iteration; Predation method 2: X 2,t+1 = X b,t ×{ s ×[( s×s ) / ( n 1 / μ )]}+ X b,t +( x )× l ×( 1-t / T ) σ= [G(1 +m )×sin(π m / 2)] / [Г((1 +m ) / 2)× m ×2 (μ-1) / 2 ] y=l ×( 1-t / T )× cosφ x = l ×( 1-t / T )× sinφ f = rand ×π / 2 in, X 2,t+1 For the second method of predation t+ Parameter values ​​updated in 1 iteration; s is the step size scaling factor; e Normal distribution N (0, s 2 ); n Normal distribution N (0,1); m is an adjustable parameter; y and x is the spiral shape parameter during the search process; l is the spiral radius; f is the spiral angle; Г(·) is the gamma function; Predation method 3: X 3,t+1 =( X b,t - X a,t )× x - rand +(( dU-dL )× rand+dL )× or in, X 3,t+1 For the third method of predation t+ Parameter values ​​updated in 1 iteration; x and or Adjustment value for mining; dU and dL are the upper and lower limits of the parameter value; Predation method 4: X 4,t+1 = Z × X b,t - (2× rand- 1)× X t × rand- 2×(1- t / T )× {s×[( s×s ) / ( n 1 / μ )]}+ rand ×(2× rand- 1) Z=t (2×rand-1) / (1-T)2 in, X 4,t+1 For the fourth method of predation t+ Parameter values ​​updated in 1 iteration; Z is the mass function; X t For the t The parameter value for the iteration.

[0009] Preferably, in S5, when the substation stops operating, the corresponding node injects power P i and Q i changes, causing the node voltage U i Redistribute, so the power flow calculation model is as follows: P ij = U i Σ jϵL(i) U j ( G ij cosθ ij +Bij sinth ij ) Q ij = U i Σ jϵL(i) U j ( G ij sinth ij -B ij cosθ ij ) The above power flow calculation model is used to calculate the power flow distribution of the power grid during the full stop and full rotation process.

[0010] Preferably, in S6, grid stability, transmission capacity, equipment overload, fault and emergency response, recovery and emergency capability, and safety margin are analyzed and evaluated based on the full stop and full rotation model of the substation.

[0011] Compared with the prior art, the present invention provides a method for constructing a full stop and full rotation model of a substation based on the main grid of a distribution network, which has the following beneficial effects: The present invention is based on the distribution network main grid model, takes the substation to which the feeder belongs as the unit, and through topological analysis, builds and generates a substation full stop and full transfer analysis model. Based on the improved Tianying optimization algorithm, with the goal of reducing operating costs, the full stop and full transfer of the substation can be quickly realized. In the event of a substation failure or emergency, the model can also quickly formulate a full stop and full transfer plan, improve the emergency response speed and processing capabilities, reduce the time and scope of power outages, and improve power supply reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a flow chart of the method mentioned in Example 1 of the present invention. DETAILED DESCRIPTION

[0013] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0014] The present invention is based on the distribution network main grid model, takes the substation to which the feeder belongs as the unit, builds and generates a substation full stop and full transfer analysis model through topological analysis, and based on the improved Tianying optimization algorithm, aims to reduce the operating cost, and quickly realizes the full stop and full transfer of the substation. In the event of a substation failure or emergency, the model can also quickly formulate a full stop and full transfer plan, improve the emergency response speed and processing capability, reduce the power outage time and scope, and improve the power supply reliability. Specifically include the following contents.

[0015] Embodiment 1: See also Figure 1 The present invention provides a method for constructing a full stop and full rotation model of a substation based on a distribution network main grid, comprising: S1: Collect the topological structure of the distribution network and the main network and the grid data related to the substation; the details are as follows: First, it is necessary to collect relevant data of the distribution network main grid, including the location, capacity, load conditions, line connection relationship of the substation, etc. At the same time, it is also necessary to obtain historical power outage data, load forecast data, and constraints on power grid operation.

[0016] For example, for a distribution network in a certain area, the following data is collected: Substation A, capacity 100MVA, current load 80MVA.

[0017] Substation B, capacity 120MVA, current load 90MVA.

[0018] S2: Preprocess and analyze the data collected by S1 and use it to establish a power grid model; the details are as follows: Build substation model and main grid model; The substation model includes: transformer: Types: including autotransformer, double-winding transformer, etc.

[0019] Capacity: Determines its maximum transmission power.

[0020] Transformation ratio: The ratio of input and output voltage.

[0021] Switchgear: Circuit breaker: used to cut off fault current.

[0022] Isolating switch: used to isolate equipment for maintenance.

[0023] Busbar: Type: such as hard busbar and soft busbar.

[0024] Ampacity: Determines its ability to transmit current.

[0025] Reactive power compensation device: Capacitor bank: provides reactive power compensation.

[0026] Reactor: Limit short-circuit current and regulate reactive power.

[0027] The mainnet model includes: Distribution Transformer: Distribution location and capacity: set according to load distribution.

[0028] Connection group: such as Dyn11, etc.

[0029] Distribution lines: Branch lines and connecting lines.

[0030] The type and size of the incoming user load.

[0031] Switching Station and Ring Main Unit: Location and Function: Used to distribute and control electrical energy.

[0032] Distributed power supply: Such as rooftop solar energy, small wind turbines, etc.

[0033] Access location and output characteristics.

[0034] Also consider component connections: Connection between substation and main grid: connected to the upper grid through high-voltage transmission lines.

[0035] Connection between the main grid and the distribution grid: High voltage electric energy is converted into medium voltage electric energy through a step-down transformer and transmitted to the distribution grid.

[0036] Connections within the distribution network: forming ring networks, radial networks or hand-in-hand structures to improve power supply reliability.

[0037] For example, in an actual power grid model, there is a 220kV substation connected to the upper power grid through two 220kV transmission lines, and there are two 180MVA main transformers in the substation. In the main grid, the transmission line uses an overhead line of model LGJ-400, with a resistance of 0.08Ω / km and a reactance of 0.4Ω / km. In the distribution network, there are multiple 10kV ring main cabinets distributed in different areas to supply power to various users.

[0038] By establishing such a complete power grid model, the operating status, power quality, reliability, etc. of the power grid can be analyzed and evaluated, providing an important reference for the planning, operation and maintenance of the power grid.

[0039] The substation model is built as follows: P 1= V 1 I 1 cosθ 1 P 2= V 2 I 2 cosθ 2 p=P+jQ = V 1 I 1 * = V 2 I 2 * in, P 1. P 2 are the active power of the primary and secondary sides of the transformer respectively; V 1. V 2 is the corresponding voltage; I 1. I 2 is the current; i 1. i 2 is the power factor angle; p is the complex power; P is the transformer active power; Q is the reactive power; j is an imaginary number; I 1 * , I 2 * For current I 1. I plural form of 2; Compensation amount of reactive power compensation device Q c It is expressed as: Q c =CV 2 in, C is the capacitance value of the compensation capacitor; V is the bus voltage; The main network model is built as follows: P ij = U i 2 G ij -U i U j ( G ij cosθ ij +B ij sinth ij ) Q ij =- U i 2 B ij +U i U j ( G ij sinthij -B ij cosθ ij ) in, P ij and Q ij Slave nodes i To Node j The active power and reactive power of U i and U j Is a node i and j The voltage amplitude, i ij Is a node i and j The voltage phase difference between G ij and B ij are the conductance and susceptance of the line respectively; Power balance constraints: Σ kϵL(i) P ik -P if = 0 Σ kϵL(i) Q ik -Q if = 0 Among them, L(i) is the node i The set of adjacent nodes; P if and Q if Is a node i Active and reactive loads; P ik and Q ik Slave nodes i To Node k Active power and reactive power; Voltage Constraints: U min ≤U i ≤U max in, U max and Umin are the maximum and minimum values ​​of the node voltage respectively; Line capacity constraints: | S ij | ≤S max,ij in, S ij For slave nodes i To Node j The power transmitted by the line; S max,ij For slave nodes i To Node j The maximum permissible value of line transmission power; Logical constraints: The line input and substation operation status conform to the actual logic; At the same time, the load model is built as follows: P i = P i0 ( α P +β P U i +g P U i 2 ) Q i = Q i0 ( α Q +β Q U i +g Q U i 2 ) in, P i and Q i Node i Active and reactive loads; P i0 and Q i0 Node i Initial active and reactive loads; α P , β P , cP , α Q , β Q , c Q is the coefficient of the load model.

[0040] S3: defines the total power outage state; the details are as follows: Defining decision variables x ij , indicating that from the substation i To the substation j Whether the line is put into use, x ij = 1 means investment, x ij = 0 means not in use. A total blackout can be defined as one or more key substations in the power grid losing power input, causing them to be unable to supply power normally, and this blackout has a wide impact, causing a large-scale power outage.

[0041] S4: Formulate a full stop and full rotation strategy; the details are as follows: When all substations are shut down, backup power is used, or the load supplied by the substation is transferred to the adjacent substation in proportion. The transfer ratio is determined based on the remaining capacity and load importance of each substation and the improved Tianying optimization algorithm. The improved Tianying optimization algorithm is as follows: Taking minimizing power outage losses as the objective function H : H = minutes Σ i oh i f i t i + Σ i,j cost ij x ij in, oh i is the load point i Importance weight of f i is the load point i of power outage load; t i is the load point i The power outage time; cost ij Is the input line i arrivej Costs; The position of the eagle, that is, the initial value of the parameter value, is obtained by the following formula: X m =( dU m -dL m )× rand+dL m in, X m For the m The initial value of the parameter value; dU m and dL m For the m upper and lower limits for parameter values; rand is a random number between (0,1); At the iteration number t ≤ 2 T / At 3, the parameter values ​​are updated by predation mode 1 and mode 2; Tianying updates the parameter values ​​at the iteration number t > 2 T / At 3, the current parameter values ​​are updated by predation methods 3 and 4; Predation method 1: X 1,t+1 = X b,t ×( 1-t / T )+( X a,t -X b,t )× rand

[0042] in, X 1,t+1 For predation method 1 t+ Parameter values ​​updated in 1 iteration; X b,t is the current optimal parameter value; T is the maximum number of iterations; X a,t is the average value of the solution; M is the number of candidate values ​​for the parameter; X i,t Load point i No. t The parameter value updated in the iteration; Predation method 2: X 2,t+1 = Xb,t ×{ s ×[( s×s ) / ( n 1 / μ )]}+ X b,t +( x )× l ×( 1-t / T ) σ= [G(1 +m )×sin(π m / 2)] / [Г((1 +m ) / 2)× m ×2 (μ-1) / 2 ] y=l ×( 1-t / T )× cosφ x = l ×( 1-t / T )× sinφ f = rand ×π / 2 in, X 2,t+1 For the second method of predation t+ Parameter values ​​updated in 1 iteration; s is the step size scaling factor; e Normal distribution N (0, s 2 ); n Normal distribution N (0,1); m is an adjustable parameter; y and x is the spiral shape parameter during the search process; l is the spiral radius; f is the spiral angle; Г(·) is the gamma function; Predation method 3: X 3,t+1 =( X b,t - X a,t )× x - rand +(( dU-dL )× rand+dL )× or in, X 3,t+1 For the third method of predation t+Parameter values ​​updated in 1 iteration; x and or Adjustment value for mining; dU and dL are the upper and lower limits of the parameter value; Predation method 4: X 4,t+1 = Z × X b,t - (2× rand- 1)× X t × rand- 2×(1- t / T )× {s×[( s×s ) / ( n 1 / μ )]}+ rand ×(2× rand- 1) Z=t (2×rand-1) / (1-T)2 in, X 4,t+1 For the fourth method of predation t+ Parameter values ​​updated in 1 iteration; Z is the mass function; X t For the t The parameter value for the iteration.

[0043] S5: Simulate a full power outage scenario and adjust the operating state of the power grid model accordingly to obtain a full power outage and full operation model of the substation; the details are as follows: When the substation stops operating, the corresponding nodes inject power P i and Q i changes, causing the node voltage U i Redistribute, so the power flow calculation model is as follows: P ij = U i Σ jϵL(i) U j ( G ij cosθ ij +B ij sinth ij ) Qij = U i Σ jϵL(i) U j ( G ij sinth ij -B ij cosθ ij ) The above power flow calculation model is used to calculate the power flow distribution of the power grid during the full stop and full rotation process.

[0044] Specifically, the power flow equation can be solved based on the Newton-Raphson method: Δ P i = P wi - U i Σ jϵL(i) U j ( G ij cosθ ij +B ij sinth ij ) Δ Q i = Q wi - U i Σ jϵL(i) U j ( G ij sinth ij -B ij cosθ ij ) Among them, Δ P i , Δ Q i is the unbalanced amount of active and reactive power; P wi , Q wi For a given injection power; Assume that there are three substations in a simple power grid model, namely D 1. D 2. D 3. In a total power outage scenario, define D1 and D 2 Stop running, that is D 1= D 2=0, D 3=1. Originally D 1 and D The injection power of 2 is P 1,n and Q 1,n and P 2,n and Q 2,n , becomes 0 after power outage. By resolving the above power flow equation, the new node voltage can be obtained U 1. U 2 and U The value of 3 reflects the voltage change after the power outage.

[0045] S6: Analyze and evaluate the response capability of the substation full stop and full rotation model. The details are as follows: The response capability assessment of the substation full shutdown and full transfer model involves several key aspects, mainly to understand the stability and reliability of the power grid when all substations are shut down or all loads are transferred. The details are as follows: Grid stability analysis: Voltage stability: Assess whether voltage levels at all points on the grid are within safe ranges after all substations have been out of service or loads have been transferred. Pay attention to the low and high points of voltage to ensure that they do not cause equipment damage or service interruptions.

[0046] Frequency response: Analyze the frequency response capability of the power grid when the load changes to ensure that the power system can maintain a stable grid frequency and avoid system collapse or equipment failure.

[0047] Transmission Capacity Assessment: Determine the maximum transmission capacity and limitations of the grid when all substations are shut down or loads are fully transferred. Consider the grid topology, line capacity, and possible bottlenecks to ensure that the safe load of any line or equipment is not exceeded.

[0048] Equipment overload analysis: Assess the risk of overloading of substation equipment after full load transfer or outage. In particular, transformers, switchgear and protection devices should be checked for thermal load and rated capacity to ensure that critical equipment will not be damaged during load changes.

[0049] Failure and emergency response: Analyze the possible faults that may occur in the power grid under simulated conditions and evaluate the ability to cope with these faults, including measures such as rapid isolation and repair of equipment, and dispatch and start-up of backup generation capacity.

[0050] Resilience and Contingency Planning: Develop and evaluate emergency response plans, including the steps and time required to restore the grid to normal operation. Consider various factors that may be involved in grid restoration, such as human resources, availability of spare parts, etc.

[0051] Model Validation and Simulation: The model is verified and simulated using power system simulation software to ensure that the model can accurately reflect the actual operating characteristics and response capabilities of the power grid. The robustness and reliability of the model are verified through different load scenarios and substation states.

[0052] Safety margin and improvement strategies: Determine the safety margin of the power grid under extreme conditions and propose improvement strategies to enhance the power grid's ability to respond to emergencies, including equipment upgrades, new equipment investments, and network planning optimization.

[0053] Combining the above steps and considerations, evaluating the responsiveness of the substation full shutdown and full rotation model not only helps identify the weaknesses and risks of the power grid, but also provides power system operators with optimized decisions and emergency plans to ensure that the power grid can maintain safe, stable and reliable operation under various conditions.

[0054] Embodiment 2: Assume that there is a distribution network consisting of three substations (A, B, C), each of which has a transformer, a busbar, and several outgoing lines.

[0055] Substation parameters can be found in Table 1: Table 1 Parameters of different substations

[0056] The line parameters can be found in Table 2: Table 2 Parameters of different lines

[0057] The load distribution in different areas can be found in Table 3: Table 3 Load distribution in different areas

[0058] All-stop and all-transfer strategy: Assume that substation A is completely shut down due to a fault.

[0059] First, the load in area 1, which was originally supplied by substation A, is transferred to substations B and C through lines BC and AC.

[0060] Make sure that substations B and C have sufficient capacity to accommodate the transferred load.

[0061] Power flow calculation: Under different conditions before and after the complete shutdown of substation A, power flow calculation is performed to determine the power distribution of each line and the voltage of the substation bus.

[0062] During normal operation, the power flow distribution meets the power supply needs of each substation, the power on the line is within the allowable range, and the bus voltage also meets the standards.

[0063] When substation A is completely shut down, a new power flow distribution is obtained through power flow calculation. For example, the power on lines BC and AC will increase, and the transformer loads of substations B and C will also change accordingly.

[0064] Assume that after all substation A stops, a certain degree of voltage fluctuation occurs on line BC, causing the actual power of some constant power loads connected to substation C to change. The original load with a power of 50MW and 25Mvar may become 48MW and 24Mvar due to voltage fluctuation. When calculating the flow, the corrected load value is used to calculate and redetermine the power distribution of each line and the voltage of the substation bus.

[0065] Model evaluation metrics: Check whether the line is overloaded, that is, whether the power on the line exceeds its maximum allowed transmission power.

[0066] Ensure that the transformer loads at substations B and C do not exceed their rated capacity.

[0067] Observe whether the bus voltage is within the acceptable range to ensure the power supply quality.

[0068] If problems are found in the simulation, such as the voltage fluctuation mentioned above, in addition to checking whether the line is overloaded and whether the bus voltage is normal, attention should also be paid to whether the voltage stability of sensitive loads meets the requirements. If the voltage fluctuation is too large and affects the normal operation of some equipment, it may be necessary to adjust the load transfer path or take other measures to reduce the impact of voltage fluctuations to ensure that full transfer can be achieved safely and reliably in the case of a full shutdown of the substation and maintain normal power supply to users.

[0069] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for constructing a full stop and full rotation model of a substation based on the main grid of a distribution network, characterized in that: The steps include: S1: Collect the topological structure of the distribution network and the main network and the grid data related to the substation; S2: pre-process and analyze the data collected by S1 and use it to build a power grid model; S3: defines a total power outage state; S4: Formulate a full stop and full turn strategy; S5: Simulate a full power outage scenario and adjust the operating state of the power grid model accordingly to obtain a full power outage and full operation model of the substation; S6: Analyze and evaluate the response capability of the substation full stop and full rotation model.

2. The method for constructing a full stop and full rotation model of a substation based on a distribution network main grid according to claim 1 is characterized in that: In S2, a substation model and a main grid model are constructed; The substation model is constructed as follows: P 1= V 1 I 1 cosθ 1 P 2= V 2 I 2 cosθ 2 p=P+jQ = V 1 I 1 * = V 2 I 2 * in, P 1. P 2 are the active power of the primary and secondary sides of the transformer respectively; V 1. V 2 is the corresponding voltage; I 1. I 2 is the current; θ 1. θ 2 is the power factor angle; p is the complex power; P is the transformer active power; Q is the reactive power; j is an imaginary number; I 1 * , I 2 * For current I 1. I plural form of 2; Compensation amount of reactive power compensation device Q c It is expressed as: Q c =CV 2 in, C is the capacitance value of the compensation capacitor; V is the bus voltage; The main network model is constructed as follows: P ij = U i 2 G ij -U i U j ( G ij cosθ ij +B ij sinθ ij ) Q ij =- U i 2 B ij +U i U j ( G ij sinθ ij -B ij cosθ ij ) in, P ij and Q ij Slave nodes i To Node j The active power and reactive power of U i and U j Is a node i and j The voltage amplitude, θ ij Is a node i and j The voltage phase difference between G ij and B ij are the conductance and susceptance of the line respectively; Power balance constraints: S kϵL(i) P ik -P if = 0 S kϵL(i) Q ik -Q if = 0 Among them, L(i) is the node i The set of adjacent nodes; P if and Q if Is a node i Active and reactive loads; P ik and Q ik Slave nodes i To Node k Active power and reactive power; Voltage Constraints: U min ≤U i ≤U max in, U max and U min are the maximum and minimum values ​​of the node voltage respectively; Line capacity constraints: | S ij | ≤S max,ij in, S ij For slave nodes i To Node j The power transmitted by the line; S max,ij For slave nodes i To Node j The maximum permissible value of line transmission power; Logical constraints: The line input and substation operation status conform to the actual logic; At the same time, the load model is built as follows: P i = P i0 ( α P +β P U i +γ P U i 2 ) Q i = Q i0 ( α Q +β Q U i +γ Q U i 2 ) in, P i and Q i Node i Active and reactive loads; P i0 and Q i0 Node i Initial active and reactive loads; α P , β P , γ P , α Q , β Q , γ Q is the coefficient of the load model.

3. The method for constructing a full stop and full rotation model of a substation based on a distribution network main grid according to claim 1, characterized in that: In S3, the full power outage state is defined as follows: Defining decision variables x ij , indicating that from the substation i To the substation j Whether the line is put into use, x ij = 1 means investment, x ij = 0 means no investment.

4. The method for constructing a full stop and full rotation model of a substation based on a distribution network main grid according to claim 1 is characterized in that: The full stop and full rotation strategy is formulated as follows: When the substation is completely shut down, the backup power supply is put into use, or the load supplied by the substation is transferred to the adjacent substation in proportion. The transfer ratio is determined based on the remaining capacity and load importance of each substation based on the improved Tianying optimization algorithm; the improved Tianying optimization algorithm is as follows: Taking the minimization of power outage losses as the objective function H : H = min S i ω i f i τ i + S i,j cost ij x ij in, ω i is the load point i The importance weight of f i is the load point i of power outage load; τ i is the load point i The power outage time; cost ij Is the input line i arrive j Costs; The position of the eagle, that is, the initial value of the parameter value, is obtained by the following formula: X m =( Ud m -dL m )× rand+dL m in, X m For the m The initial value of the parameter value; Ud m and dL m For the m upper and lower limits for parameter values; rand is a random number between (0,1); At the iteration number t ≤ 2 T / At 3, the parameter values ​​are updated by predation mode 1 and mode 2; Tianying updates the parameter values ​​at the iteration number t > 2 T / At 3, the current parameter values ​​are updated by predation methods 3 and 4; Predation method 1: X 1,t+1 = X b,t ×( 1-t / T )+( X a,t -X b,t )× rand in, X 1,t+1 For predation method 1 t+ Parameter values ​​updated in 1 iteration; X b,t is the current optimal parameter value; T is the maximum number of iterations; X a,t is the average value of the solution; M is the number of candidate values ​​for the parameter; X i,t Load point i No. t The parameter value updated in the iteration; Predation method 2: X 2,t+1 = X b,t ×{ s ×[( ε×σ ) / ( ν 1 / μ )]}+ X b,t +( yx )× l ×( 1-t / T ) σ = [Г(1 +μ )×sin(π μ / 2)] / [G((1 +μ ) / 2)× μ ×2 (μ-1) / 2 ] y=l ×( 1-t / T )× cosφ x = l ×( 1-t / T )× sinφ φ = rand ×π / 2 in, X 2,t+1 For the second method of predation t+ Parameter values ​​updated in 1 iteration; s is the step size scaling factor; ε Normal distribution N (0, σ 2 ); ν Normal distribution N (0,1); μ is an adjustable parameter; y and x is the spiral shape parameter during the search process; l is the spiral radius; φ is the spiral angle; Г(·) is the gamma function; Predation method 3: X 3,t+1 =( X b,t - X a,t )× ξ - rand +(( dU )× rand+dL )× η in, X 3,t+1 For the third method of predation t+ Parameter values ​​updated in 1 iteration; ξ and η Adjustment value for mining; Ud and dL are the upper and lower limits of the parameter value; Predation method 4: X 4,t+1 = Z × X b,t - (2× rand- 1)× X t × rand- 2×(1- t / T )× {s×[( ε×σ ) / ( ν 1 / μ )]}+ rand ×(2× rand- 1) Z=t (2×rand-1) / (1-T)2 in, X 4,t+1 For predation method 4 t+ Parameter values ​​updated in 1 iteration; Z is the mass function; X t For the t The parameter value for the iteration.

5. The method for constructing a full stop and full rotation model of a substation based on a distribution network main grid according to claim 1, characterized in that: In S5, when the substation stops operating, the corresponding node injects power P i and Q i changes, causing the node voltage U i Redistribute, so the power flow calculation model is as follows: P ij = U i S jϵL(i) U j ( G ij cosθ ij +B ij sinθ ij ) Q ij = U i S jϵL(i) U j ( G ij sinθ ij -B ij cosθ ij ) The above power flow calculation model is used to calculate the power flow distribution of the power grid during the full stop and full rotation process.

6. The method for constructing a full stop and full rotation model of a substation based on a distribution network main grid according to claim 1, characterized in that: In S6, the grid stability, transmission capacity, equipment overload, fault and emergency response, recovery and emergency response capability, and safety margin are analyzed and evaluated based on the full stop and full rotation model of the substation.

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