CN112529370A - Natural gas system reliability assessment method and system considering dynamic effect - Google Patents
Natural gas system reliability assessment method and system considering dynamic effect Download PDFInfo
- Publication number
- CN112529370A CN112529370A CN202011333595.4A CN202011333595A CN112529370A CN 112529370 A CN112529370 A CN 112529370A CN 202011333595 A CN202011333595 A CN 202011333595A CN 112529370 A CN112529370 A CN 112529370A
- Authority
- CN
- China
- Prior art keywords
- natural gas
- reliability
- gas system
- node
- state
- 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
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 title claims abstract description 378
- 239000003345 natural gas Substances 0.000 title claims abstract description 189
- 238000000034 method Methods 0.000 title claims abstract description 27
- 230000000694 effects Effects 0.000 title claims abstract description 23
- 239000007789 gas Substances 0.000 claims description 59
- 150000001875 compounds Chemical class 0.000 claims description 42
- 238000004364 calculation method Methods 0.000 claims description 12
- 238000011156 evaluation Methods 0.000 claims description 11
- 238000007906 compression Methods 0.000 claims description 8
- 230000006835 compression Effects 0.000 claims description 8
- 230000007246 mechanism Effects 0.000 claims description 8
- 238000004519 manufacturing process Methods 0.000 claims description 6
- 230000005540 biological transmission Effects 0.000 claims description 5
- 238000010438 heat treatment Methods 0.000 claims description 4
- 230000009467 reduction Effects 0.000 claims description 4
- 238000010586 diagram Methods 0.000 description 4
- 238000004458 analytical method Methods 0.000 description 3
- 230000010485 coping Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000003745 diagnosis Methods 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06Q—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
- G06Q10/00—Administration; Management
- G06Q10/06—Resources, workflows, human or project management; Enterprise or organisation planning; Enterprise or organisation modelling
- G06Q10/063—Operations research, analysis or management
- G06Q10/0639—Performance analysis of employees; Performance analysis of enterprise or organisation operations
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06Q—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
- G06Q10/00—Administration; Management
- G06Q10/06—Resources, workflows, human or project management; Enterprise or organisation planning; Enterprise or organisation modelling
- G06Q10/067—Enterprise or organisation modelling
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06Q—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
- G06Q50/00—Information and communication technology [ICT] specially adapted for implementation of business processes of specific business sectors, e.g. utilities or tourism
- G06Q50/06—Energy or water supply
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
- Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
- Y04S10/00—Systems supporting electrical power generation, transmission or distribution
- Y04S10/50—Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications
Landscapes
- Business, Economics & Management (AREA)
- Human Resources & Organizations (AREA)
- Engineering & Computer Science (AREA)
- Economics (AREA)
- Strategic Management (AREA)
- Entrepreneurship & Innovation (AREA)
- Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Marketing (AREA)
- Educational Administration (AREA)
- Development Economics (AREA)
- Tourism & Hospitality (AREA)
- General Physics & Mathematics (AREA)
- General Business, Economics & Management (AREA)
- Health & Medical Sciences (AREA)
- Game Theory and Decision Science (AREA)
- Operations Research (AREA)
- Quality & Reliability (AREA)
- Public Health (AREA)
- General Health & Medical Sciences (AREA)
- Water Supply & Treatment (AREA)
- Primary Health Care (AREA)
- Management, Administration, Business Operations System, And Electronic Commerce (AREA)
- Testing And Monitoring For Control Systems (AREA)
Abstract
The invention discloses a natural gas system reliability assessment method and system considering dynamic effect, wherein the method comprises the following steps: collecting operation data of a natural gas system, and determining the operation state of the natural gas system; establishing an element reliability model for each element according to the running state of the natural gas system; constructing a system reliability model based on the element reliability model; and calculating the reliability parameters of the natural gas system, and judging the reliability of the natural gas system. The method can accurately and effectively calculate the reliability of the natural gas system, and ensures the safe and reliable operation of the natural gas system.
Description
Technical Field
The invention relates to a natural gas system reliability assessment method and system considering dynamic effects, and belongs to the technical field of energy system reliability diagnosis.
Background
At present, with frequent extreme weather such as earthquake, typhoon and tsunami, the problem of reliable operation of a natural gas system is increasingly prominent. In daily operation, factors such as extreme weather can cause a certain element in a natural gas system to break down, and finally, a large-scale gas stopping accident of the natural gas system can be caused. Therefore, the corresponding reliability evaluation and analysis work of the natural gas system needs to be developed urgently, and a foundation is laid for the reliable operation of the system.
The existing natural gas system reliability evaluation method only considers the steady-state operation process of the natural gas system, namely after a fault occurs, the system is supposed to be transited from one operation state to another operation state instantly. In fact, due to the fact that a natural gas system can store natural gas (hereinafter referred to as "storage in pipe") and has a low movement rate, transition between operation states is slow, and therefore, the traditional analysis method is difficult to effectively reflect the actual operation state of the system. Therefore, a reasonable and correct analysis method is still lacked at the present stage, and the reliability of the natural gas system can be accurately and effectively evaluated, so that the formulation of measures for improving the reliability of the natural gas system is also blind.
Disclosure of Invention
Aiming at the defects of the method, the invention provides the natural gas system reliability assessment method and system considering the dynamic effect, which can accurately and effectively calculate the reliability of the natural gas system and ensure the safe and reliable operation of the natural gas system.
The technical scheme adopted for solving the technical problems is as follows:
on one hand, the natural gas system reliability assessment method considering the dynamic effect provided by the embodiment of the invention comprises the following steps:
collecting operation data of a natural gas system, and determining the operation state of the natural gas system;
establishing an element reliability model for each element according to the running state of the natural gas system;
constructing a system reliability model based on the element reliability model;
and calculating the reliability parameters of the natural gas system, and judging the reliability of the natural gas system.
As a possible implementation manner of this embodiment, the operation data of the natural gas system includes the capacity of the pipeline, the upper limit of the production of the gas source, and the natural gas load of the node.
As a possible implementation manner of this embodiment, the element reliability model includes a reliability model of the gas source and a reliability model of the gas storage device,
reliability model u of the gas sourceih(z, t) is:
in the formula (I), the compound is shown in the specification,
and
respectively represent states lihThe upper limit of the output of the air source h at the lower node i and the corresponding probability, the air source h has K in totalihA state; z is used for distinguishing the values and probabilities of the variables; t is used to refer to time;
reliability model u of the gas storage deviceiq(z, t) is:
in the formula (I), the compound is shown in the specification,
and
respectively represent states liqThe upper limit of the output of the gas storage device q at the lower node i and the corresponding probability, the gas source q is K in totaliqAnd (4) a state.
As a possible implementation manner of this embodiment, the building a system reliability model based on the element reliability model specifically includes: introducing a natural gas dynamic power flow calculation operator omega based on an element reliability modelφOTGFAggregating different element reliability models to construct a system reliability model
In the formula (I), the compound is shown in the specification,
and pl(t) respectively representing the load shedding amount and the corresponding probability of the node i under the state l and the moment t; k represents the total state number of the system; phi represents a functional relation; OTGF is used to refer to natural gas system dynamic load flow calculations.
As a possible implementation manner of this embodiment, the objective function of the system reliability model is:
in the formula (I), the compound is shown in the specification,
representing the load shedding amount of the node i under the state l and the time t + delta t; n represents the total number of nodes in the natural gas system;
the constraints of the system reliability model include:
pipeline continuity equation:
in the formula (I), the compound is shown in the specification,
indicating the inventory of the pipeline D at state l and time t; Δ x represents the length of the pipe; d represents the diameter of the pipe; r represents the heating value of natural gas; psi denotes the coefficient of friction of the pipe; z represents a compression factor; rhonRepresents the density of natural gas;
and
respectively representing the pressure intensity of a node j and a node i at two ends of the pipeline D at the state l and the moment t;
the continuity equation for the pipeline is:
in the formula (I), the compound is shown in the specification,
and
respectively representing the natural gas flow of a node i and a node j at two ends of the pipeline D at the state l and the moment t + delta t;
the pipeline power equation:
in the formula (I), the compound is shown in the specification,
represents the average flow on the pipe D at state i and at time t + Δ t; v represents the flow rate of natural gas; f represents the transmission coefficient of the pipeline;
node gas flow balance equation:
in the formula (I), the compound is shown in the specification,
and
respectively representing the state l and the time t + delta t at the node iqAnd the output of gas source h;
representing the natural gas load of the node i at the state l and the time t; n is a radical ofDRepresenting the total number of natural gas pipelines;
the constraints of the compressor are as follows:
in the formula (I), the compound is shown in the specification, cijξand
respectively representing the minimum value and the maximum value of the compression coefficient of the compressor c;
the constraint conditions of the node air pressure are as follows:
in the formula (I), the compound is shown in the specification,
and
respectively representing the minimum value and the maximum value of the air pressure of the node i under the state l;
the constraint conditions of the pipeline flow are as follows:
in the formula (I), the compound is shown in the specification,
and
respectively representing the lower limit and the upper limit of the natural gas flow of the pipeline D under the state l;
the output constraint conditions of the gas source are as follows:
the output constraint conditions of gas storage are as follows:
the natural gas load reduction constraint conditions are as follows:
as a possible implementation manner of this embodiment, the calculating a reliability parameter of the natural gas system and performing reliability judgment on the natural gas system specifically includes:
calculating the average load shedding amount of the natural gas system:
wherein EGNS (T) represents the average load shedding of the natural gas system over a total time T;
if the average load shedding amount of the system in the total time T is less than the threshold EGNSlimitWhen the EGNS (T) is less than or equal to EGNSlimitIf the natural gas system is in the normal state, the reliability of the natural gas system is considered to meet the requirement, and adjustment is not needed; if the system does not meet the requirements, the scheduling mechanism is required to adjust the operation mode, so that the safe and reliable operation of the system is ensured.
In another aspect, a natural gas system reliability evaluation system considering dynamic effects provided in an embodiment of the present invention includes:
the data acquisition module is used for acquiring the operation data of the natural gas system and determining the operation state of the natural gas system;
the component model establishing module is used for establishing a component reliability model aiming at each component according to the running state of the natural gas system;
the system model building module is used for building a system reliability model based on the element reliability model;
and the reliability judgment module is used for calculating the reliability parameters of the natural gas system and judging the reliability of the natural gas system.
As a possible implementation manner of this embodiment, the operation data of the natural gas system includes the capacity of the pipeline, the upper limit of the production of the gas source, and the natural gas load of the node.
As a possible implementation manner of this embodiment, the element reliability model includes a reliability model of the gas source and a reliability model of the gas storage device.
As a possible implementation manner of this embodiment, the reliability parameter of the natural gas system is an average load shedding amount of the natural gas system.
The technical scheme of the embodiment of the invention has the following beneficial effects:
according to the method, firstly, the running data of the system is collected through a sensor of the natural gas system, the running state of the system is determined according to the collected data, and on the basis of the current running state, a reliability model of an element is firstly established according to the parameters of the element, then, the models of different elements are aggregated by using a natural gas dynamic power flow calculation operator, the reliability model of the natural gas system is established, and the reliability parameters of the system are calculated. The method can accurately and effectively calculate the reliability of the natural gas system, and when the reliability of the system has problems, the method can issue early warning signals to the scheduling mechanism to assist the scheduling mechanism to arrange corresponding coping strategies, and has important significance for ensuring the safe and reliable operation of the natural gas system.
Description of the drawings:
FIG. 1 is a flow diagram illustrating a method for natural gas system reliability assessment that accounts for dynamic effects in accordance with an exemplary embodiment;
FIG. 2 is a schematic block diagram of a natural gas system according to an exemplary embodiment;
FIG. 3 is a schematic diagram illustrating the structure of a natural gas system reliability evaluation system that accounts for dynamic effects in accordance with an exemplary embodiment.
Detailed Description
The invention is further illustrated by the following examples in conjunction with the accompanying drawings:
in order to clearly explain the technical features of the present invention, the following detailed description of the present invention is provided with reference to the accompanying drawings. The following disclosure provides many different embodiments, or examples, for implementing different features of the invention. To simplify the disclosure of the present invention, the components and arrangements of specific examples are described below. Furthermore, the present invention may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. It should be noted that the components illustrated in the figures are not necessarily drawn to scale. Descriptions of well-known components and processing techniques and procedures are omitted so as to not unnecessarily limit the invention.
FIG. 1 is a flow diagram illustrating a method for natural gas system reliability assessment that accounts for dynamic effects in accordance with an exemplary embodiment. As shown in fig. 1, a method for evaluating reliability of a natural gas system considering dynamic effects according to an embodiment of the present invention includes the following steps:
collecting operation data of a natural gas system, and determining the operation state of the natural gas system;
establishing an element reliability model for each element according to the running state of the natural gas system;
constructing a system reliability model based on the element reliability model;
and calculating the reliability parameters of the natural gas system, and judging the reliability of the natural gas system.
As shown in fig. 2, the natural gas system mainly includes four parts, namely a gas source, a gas pipeline, a compressor and a natural gas load. Wherein, the natural gas node may have air supply and natural gas load, and the natural gas node is connected through gas transmission pipeline or compressor.
As a possible implementation manner of this embodiment, the operation data of the natural gas system includes the capacity of the pipeline, the upper limit of the production of the gas source, and the natural gas load of the node.
As a possible implementation manner of this embodiment, the element reliability model includes a reliability model of the gas source and a reliability model of the gas storage device,
reliability model u of the gas sourceih(z, t) is:
in the formula (I), the compound is shown in the specification,
and
respectively represent states lihThe upper limit of the output of the air source h at the lower node i and the corresponding probability, the air source h has K in totalihA state; z is used for distinguishing the values and probabilities of the variables; t is used to refer to time;
reliability model u of the gas storage deviceiq(z, t) is:
in the formula (I), the compound is shown in the specification,
and
respectively represent states liqThe upper limit of the output of the gas storage device q at the lower node i and the corresponding probability, the gas source q is K in totaliqAnd (4) a state.
As a possible implementation manner of this embodiment, the building a system reliability model based on the element reliability model specifically includes: introducing a natural gas dynamic power flow calculation operator omega based on an element reliability modelφOTGFAggregating different element reliability models to construct a system reliability model
In the formula (I), the compound is shown in the specification,
and pl(t) respectively representing the load shedding amount and the corresponding probability of the node i under the state l and the moment t; k represents the total state number of the system; phi represents a functional relation; OTGF is used to refer to natural gas system dynamic load flow calculations.
As a possible implementation manner of this embodiment, the objective function of the system reliability model is:
in the formula (I), the compound is shown in the specification,
representing the load shedding amount of the node i under the state l and the time t + delta t; n represents the total number of nodes in the natural gas system;
the constraints of the system reliability model include:
pipeline continuity equation:
in the formula (I), the compound is shown in the specification,
indicating the inventory of the pipeline D at state l and time t; Δ x represents the length of the pipe; d represents the diameter of the pipe; r represents the heating value of natural gas; psi denotes the coefficient of friction of the pipe; z represents a compression factor; rhonRepresents the density of natural gas;
and
respectively representing the pressure intensity of a node j and a node i at two ends of the pipeline D at the state l and the moment t;
the continuity equation for the pipeline is:
in the formula (I), the compound is shown in the specification,
and
respectively representing the natural gas flow of a node i and a node j at two ends of the pipeline D at the state l and the moment t + delta t;
the pipeline power equation:
in the formula (I), the compound is shown in the specification,
represents the average flow on the pipe D at state i and at time t + Δ t; v represents the flow rate of natural gas; f represents the transmission coefficient of the pipeline;
node gas flow balance equation:
in the formula (I), the compound is shown in the specification,
and
respectively representing the state l and the time t + delta t at the node iqAnd the output of gas source h;
representing the natural gas load of the node i at the state l and the time t; ND represents the total number of natural gas pipelines;
the constraints of the compressor are as follows:
in the formula (I), the compound is shown in the specification, cijξand
respectively representing the minimum value and the maximum value of the compression coefficient of the compressor c;
the constraint conditions of the node air pressure are as follows:
in the formula (I), the compound is shown in the specification,
and
respectively representing the minimum value and the maximum value of the air pressure of the node i under the state l;
the constraint conditions of the pipeline flow are as follows:
in the formula (I), the compound is shown in the specification,
and
respectively representing the lower limit and the upper limit of the natural gas flow of the pipeline D under the state l;
the output constraint conditions of the gas source are as follows:
the output constraint conditions of gas storage are as follows:
the natural gas load reduction constraint conditions are as follows:
as a possible implementation manner of this embodiment, the calculating a reliability parameter of the natural gas system and performing reliability judgment on the natural gas system specifically includes:
calculating the average load shedding amount of the natural gas system:
wherein EGNS (T) represents the average load shedding of the natural gas system over a total time T;
if the average load shedding amount of the system in the total time T is less than the threshold EGNSlimitWhen the EGNS (T) is less than or equal to EGNSlimitIf the natural gas system is in the normal state, the reliability of the natural gas system is considered to meet the requirement, and adjustment is not needed; if the system does not meet the requirements, the scheduling mechanism is required to adjust the operation mode, so that the safe and reliable operation of the system is ensured.
As shown in fig. 3, a system for evaluating reliability of a natural gas system considering dynamic effects according to an embodiment of the present invention includes:
the data acquisition module is used for acquiring the operation data of the natural gas system and determining the operation state of the natural gas system;
the component model establishing module is used for establishing a component reliability model aiming at each component according to the running state of the natural gas system;
the system model building module is used for building a system reliability model based on the element reliability model;
and the reliability judgment module is used for calculating the reliability parameters of the natural gas system and judging the reliability of the natural gas system.
As a possible implementation manner of this embodiment, the operation data of the natural gas system includes the capacity of the pipeline, the upper limit of the production of the gas source, and the natural gas load of the node.
As a possible implementation manner of this embodiment, the element reliability model includes a reliability model of the gas source and a reliability model of the gas storage device.
As a possible implementation manner of this embodiment, the reliability parameter of the natural gas system is an average load shedding amount of the natural gas system.
The method for evaluating the reliability of the natural gas system by the natural gas system reliability evaluation system considering the dynamic effect comprises the following steps:
1) collecting natural gas system data through a sensor before reliability calculation, and determining the running state of the system, wherein the method comprises the following steps: the capacity of the pipeline, the upper limit of the yield of the gas source, the natural gas load of the node and the like.
2) Based on the determined operating condition of the natural gas system, reliability modeling is sequentially carried out on the elements by using a general generating function in combination with the operating characteristics of the elements:
2.1) reliability model of gas Source
Reliability model u of gas sourceih(z, t) can be generally expressed as a multi-state model as follows:
in the formula (I), the compound is shown in the specification,
and
respectively represent states lihThe upper limit of the output of the air source h at the lower node i and the corresponding probability, the air source h has K in totalihA state; z is used for distinguishing the values and probabilities of the variables; t is used to refer to time.
2.2) reliability model of gas storage device
Reliability model u of gas storage deviceiq(z, t) can be generally expressed as a multi-state model as follows:
in the formula (I), the compound is shown in the specification,
and
respectively represent states liqThe upper limit of the output of the gas storage device q at the lower node i and the corresponding probability, the gas source q is K in totaliqAnd (4) a state.
3) Introducing a natural gas dynamic power flow calculation operator omega based on the determined reliability model of each elementφOTGFAggregating models of different elements to construct a reliability model of a natural gas system
In the formula (I), the compound is shown in the specification,
and pl(t) respectively representing the load shedding amount and the corresponding probability of the node i under the state l and the moment t; k represents the total state number of the system; phi represents a functional relation; OTGF is used to refer to natural gas system dynamic load flow calculations.
ΩφOTGFThe natural gas dynamic load flow calculation operator is mainly used for calculating the natural gas load shedding amount of the system at the t + delta t moment according to the running state of the system at the t moment under the state l, and a solved model can be expressed as follows:
a) the objective function of the model is:
in the formula (I), the compound is shown in the specification,
representing the load shedding amount of the node i under the state l and the time t + delta t; n represents the total number of nodes in the natural gas system.
The constraints of the model include:
b) equation of continuity for pipeline
In consideration of the storage characteristics of the natural gas system, a part of the natural gas may be stored in the pipeline, and thus the injection amount and the outflow amount of the natural gas in the pipeline D are different. In the states of l andpipeline D's pipe deposit when moment t
Can be expressed as:
wherein Δ x represents the length of the pipe; d represents the diameter of the pipe; r represents the heating value of natural gas; psi denotes the coefficient of friction of the pipe; z represents a compression factor; rhonRepresents the density of natural gas;
and
and respectively representing the pressure of the node j and the node i at two ends of the pipeline D at the state l and the moment t.
Based on the obtained inventory, the continuity equation of the pipeline can be expressed as:
in the formula (I), the compound is shown in the specification,
and
and respectively representing the natural gas flow of the node i and the node j at two ends of the pipeline D at the state l and the moment t + delta t.
c) Equation of pipe dynamics
The power equation of the pipeline is mainly used for describing the change situation of the natural gas flow in the pipeline along with the time, and can be specifically expressed as follows:
in the formula (I), the compound is shown in the specification,
represents the average flow on the pipe D at state i and at time t + Δ t; v represents the flow rate of natural gas; and F represents the transmission coefficient of the pipeline.
d) Nodal gas flow balance equation
For any natural gas node, the natural gas inflow is equal to the outflow, which is specifically expressed as:
in the formula (I), the compound is shown in the specification,
and
respectively representing the state l and the time t + delta t at the node iqAnd the output of gas source h;
representing the natural gas load of the node i at the state l and the time t; n is a radical ofDRepresenting the total number of natural gas pipelines.
e) Compressor restraint
The constraints of the compressor can be expressed as:
in the formula, xicijAnd
respectively representing the minimum and maximum values of the compression factor of the compressor c.
f) Node air pressure restraint
The air pressure of each node is within a certain range, which is specifically represented as:
in the formula (I), the compound is shown in the specification,
and
respectively representing the minimum value and the maximum value of the air pressure of the node i under the state l.
g) Pipe flow restraint
The constraint of the flow of each pipeline is within a certain range, which is specifically expressed as:
in the formula (I), the compound is shown in the specification,
and
respectively representing the lower limit and the upper limit of the natural gas flow rate of the pipeline D under the state l.
h) Output constraint of gas source and gas storage device
The output constraint of the gas source is expressed as:
the output constraint of gas storage is expressed as:
i) natural gas load shedding constraints
The reduction of the natural gas load of each node meets the following constraint:
the natural gas dynamic load flow model can be solved by adopting an interior point method, and the removal amount of the natural gas load of each node in different states is obtained through calculation.
4) Based on the determined removal amount of the natural gas load of each node in different states, the reliability parameter of the natural gas system can be calculated, and is expressed as:
where egns (T) represents the average load cut of the natural gas system over the total time T, obtained by integration.
Based on this, if the average load shedding amount of the system in the total time T is smaller than the threshold value, namely the formula (16) is met, the reliability of the natural gas system is considered to meet the requirement, and adjustment is not needed; if the system does not meet the requirements, the scheduling mechanism is required to adjust the operation mode, so that the safe and reliable operation of the system is ensured.
EGNS(T)≤EGNSlimit (16)
In the formula, EGNSlimitA threshold value representing the average load shedding amount.
Because the dynamic characteristic of the natural gas system is coupled to the system reliability modeling, the evaluation method provided by the invention can more accurately and effectively calculate the reliability of the natural gas system and judge whether the system can safely and reliably operate. When the system has a reliability problem, the early warning signal can be rapidly issued to the scheduling mechanism to help the scheduling mechanism to arrange a coping strategy, and the method has important significance for ensuring the reliable operation of the natural gas system.
The reliability evaluation method and the model provided by the invention can be coupled to a regulation and control platform of a natural gas system, the reliability of the natural gas system is monitored and visually displayed in real time, a dynamic reliability monitoring means is provided for the natural gas system, and the safety and the reliability of the system can be improved.
The foregoing is only a preferred embodiment of the present invention, and it will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the principle of the present invention, and these modifications and improvements are also considered to be within the scope of the present invention.
Claims (10)
1. A natural gas system reliability assessment method considering dynamic effects is characterized by comprising the following steps:
collecting operation data of a natural gas system, and determining the operation state of the natural gas system;
establishing an element reliability model for each element according to the running state of the natural gas system;
constructing a system reliability model based on the element reliability model;
and calculating the reliability parameters of the natural gas system, and judging the reliability of the natural gas system.
2. The natural gas system reliability assessment method considering dynamic effect according to claim 1, wherein the operation data of the natural gas system comprises the capacity of the pipeline, the upper limit of the production of the gas source and the natural gas load of the node.
3. The natural gas system reliability evaluation method considering dynamic effects as claimed in claim 2, wherein the element reliability model includes a reliability model of a gas source and a reliability model of a gas storage device,
reliability model u of the gas sourceih(z, t) is:
in the formula (I), the compound is shown in the specification,
and
respectively represent states lihThe upper limit of the output of the air source h at the lower node i and the corresponding probability, the air source h has K in totalihA state; z is used for distinguishing the values and probabilities of the variables; t is used to refer to time;
reliability model u of the gas storage deviceiq(z, t) is:
in the formula (I), the compound is shown in the specification,
and
respectively represent states liqThe upper limit of the output of the gas storage device q at the lower node i and the corresponding probability, the gas source q is K in totaliqAnd (4) a state.
4. The natural gas system reliability assessment method considering dynamic effects as claimed in claim 3, wherein said component reliability model-based system reliability model is constructed by: introducing a natural gas dynamic power flow calculation operator omega based on an element reliability modelφOTGFAggregating different element reliability models to construct a system reliability model
In the formula (I), the compound is shown in the specification,
and pl(t) respectively representing the load shedding amount and the corresponding probability of the node i under the state l and the moment t; k represents the total state number of the system; phi represents a functional relation; OTGF is used to refer to natural gas system dynamic load flow calculations.
5. The natural gas system reliability assessment method considering dynamic effects according to claim 4, wherein the objective function of the system reliability model is:
in the formula (I), the compound is shown in the specification,
representing the load shedding amount of the node i under the state l and the time t + delta t; n represents the total number of nodes in the natural gas system;
the constraints of the system reliability model include:
pipeline continuity equation:
in the formula (I), the compound is shown in the specification,
indicating the inventory of the pipeline D at state l and time t; Δ x represents the length of the pipe; d represents the diameter of the pipe; r represents the heating value of natural gas; psi denotes the coefficient of friction of the pipe; z represents a compression factor; rhonRepresents the density of natural gas;
and
respectively representing the state l and the time t of the pipelineThe pressure intensity of a node j and a node i at two ends of the D;
the continuity equation for the pipeline is:
in the formula (I), the compound is shown in the specification,
and
respectively representing the natural gas flow of a node i and a node j at two ends of the pipeline D at the state l and the moment t + delta t;
the pipeline power equation:
in the formula (I), the compound is shown in the specification,
represents the average flow on the pipe D at state i and at time t + Δ t; v represents the flow rate of natural gas; f represents the transmission coefficient of the pipeline;
node gas flow balance equation:
in the formula (I), the compound is shown in the specification,
and
respectively representing the state l and the time t + delta t at the node iqAnd the output of gas source h;
representing the natural gas load of the node i at the state l and the time t; n is a radical ofDRepresenting the total number of natural gas pipelines;
the constraints of the compressor are as follows:
in the formula (I), the compound is shown in the specification, cijξand
respectively representing the minimum value and the maximum value of the compression coefficient of the compressor c;
the constraint conditions of the node air pressure are as follows:
in the formula (I), the compound is shown in the specification,
and
respectively representing the minimum value and the maximum value of the air pressure of the node i under the state l;
the constraint conditions of the pipeline flow are as follows:
in the formula (I), the compound is shown in the specification,
and
respectively represent statesl lower and upper limits of natural gas flow in the pipeline D;
the output constraint conditions of the gas source are as follows:
the output constraint conditions of gas storage are as follows:
the natural gas load reduction constraint conditions are as follows:
6. the natural gas system reliability assessment method considering dynamic effect as claimed in claim 5, wherein said calculating the natural gas system reliability parameter and making the natural gas system reliability judgment specifically comprises:
calculating the average load shedding amount of the natural gas system:
wherein EGNS (T) represents the average load shedding of the natural gas system over a total time T;
if the average load shedding amount of the system in the total time T is less than the threshold EGNSlimitWhen the EGNS (T) is less than or equal to EGNSlimitIf the natural gas system is in the normal state, the reliability of the natural gas system is considered to meet the requirement, and adjustment is not needed; if the system does not meet the requirements, the scheduling mechanism is required to adjust the operation mode, so that the safe and reliable operation of the system is ensured.
7. A natural gas system reliability assessment system that considers dynamic effects, comprising:
the data acquisition module is used for acquiring the operation data of the natural gas system and determining the operation state of the natural gas system;
the component model establishing module is used for establishing a component reliability model aiming at each component according to the running state of the natural gas system;
the system model building module is used for building a system reliability model based on the element reliability model;
and the reliability judgment module is used for calculating the reliability parameters of the natural gas system and judging the reliability of the natural gas system.
8. The natural gas system reliability evaluation system considering dynamic effect according to claim 7, wherein the operation data of the natural gas system includes capacity of a pipeline, an upper limit of production of a gas source, and a natural gas load of a node.
9. The natural gas system reliability evaluation system considering dynamic effects of claim 7 wherein the element reliability model includes a reliability model of a gas source and a reliability model of a gas storage device.
10. The natural gas system reliability evaluation system considering dynamic effect according to claim 7 wherein the natural gas system reliability parameter is an average load shedding amount of the natural gas system.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011333595.4A CN112529370B (en) | 2020-11-24 | 2020-11-24 | Natural gas system reliability assessment method and system considering dynamic effect |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011333595.4A CN112529370B (en) | 2020-11-24 | 2020-11-24 | Natural gas system reliability assessment method and system considering dynamic effect |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112529370A true CN112529370A (en) | 2021-03-19 |
| CN112529370B CN112529370B (en) | 2022-09-13 |
Family
ID=74993163
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011333595.4A Active CN112529370B (en) | 2020-11-24 | 2020-11-24 | Natural gas system reliability assessment method and system considering dynamic effect |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112529370B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112783676A (en) * | 2020-12-31 | 2021-05-11 | 南京航空航天大学 | Storage system soft error resistance reliability modeling and evaluating method based on Z language |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108767852A (en) * | 2018-06-15 | 2018-11-06 | 浙江大学 | A kind of electric-gas coupled system node reliability estimation method |
| CN108921727A (en) * | 2018-06-30 | 2018-11-30 | 天津大学 | Consider the regional complex energy resource system reliability estimation method of thermic load dynamic characteristic |
| CN108921404A (en) * | 2018-06-15 | 2018-11-30 | 浙江大学 | A kind of reliability estimation method of the electric-gas coupled system based on general generating function |
-
2020
- 2020-11-24 CN CN202011333595.4A patent/CN112529370B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108767852A (en) * | 2018-06-15 | 2018-11-06 | 浙江大学 | A kind of electric-gas coupled system node reliability estimation method |
| CN108921404A (en) * | 2018-06-15 | 2018-11-30 | 浙江大学 | A kind of reliability estimation method of the electric-gas coupled system based on general generating function |
| CN108921727A (en) * | 2018-06-30 | 2018-11-30 | 天津大学 | Consider the regional complex energy resource system reliability estimation method of thermic load dynamic characteristic |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112783676A (en) * | 2020-12-31 | 2021-05-11 | 南京航空航天大学 | Storage system soft error resistance reliability modeling and evaluating method based on Z language |
| CN112783676B (en) * | 2020-12-31 | 2022-09-20 | 南京航空航天大学 | Storage system soft error resistance reliability modeling and evaluating method based on Z language |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112529370B (en) | 2022-09-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US11922335B2 (en) | Method and system for evaluating macro resilience of offshore oil well control equipment | |
| CN108051211B (en) | A kind of wind generator set main shaft holds temperature pre-warning diagnostic method | |
| CN114559819B (en) | Electric automobile battery safety early warning method based on signal processing | |
| CN108376298B (en) | Early warning and diagnosing method for temperature faults of engine of wind turbine generator | |
| CN103323772B (en) | Based on the running status of wind generator analytical approach of neural network model | |
| CN106662072A (en) | Wind turbine condition monitoring method and system | |
| CN108360608B (en) | Pipe burst identification and positioning method for water delivery pipe of water supply system | |
| CN110619587B (en) | Method and system for foundation pit monitoring intelligent early warning and data evidence storage | |
| CN103925155B (en) | The self-adapting detecting method that a kind of Wind turbines output is abnormal | |
| CN111823952A (en) | Battery cell temperature diagnosis method, storage medium and electronic equipment | |
| CN109458296B (en) | Wind vane fault-tolerant control method and device, controller and wind generating set | |
| CN113177646B (en) | Power distribution equipment online monitoring method and system based on self-adaptive edge proxy | |
| CN108830335A (en) | Photovoltaic plant fault early warning method and system | |
| CN104976139A (en) | Mechanical equipment state diagnosis method based on Gaussian model | |
| CN115437344A (en) | Digital twin comprehensive energy fault diagnosis system, method, device and medium | |
| CN112529370B (en) | Natural gas system reliability assessment method and system considering dynamic effect | |
| CN112288298B (en) | On-line data-based health condition evaluation method for desulfurization system | |
| Liu et al. | Reliability evaluation of a wind-diesel hybrid power system with battery bank using discrete wind speed frame analysis | |
| CN108506171B (en) | A kind of large-scale half direct-drive unit cooling system for gear box fault early warning method | |
| CN103617105B (en) | A kind of adaptive multi-layer flow model facility diagnosis method based on data-driven | |
| CN112994101A (en) | Neural network-based wind power plant generated power post-evaluation and monitoring method | |
| CN114442543A (en) | Computer monitoring method suitable for early warning of hydropower station fault | |
| CN106325258A (en) | Relay protection device state assessment method based on online monitoring information | |
| CN111765052B (en) | Wind speed correction method, device and system of wind generating set and storage medium | |
| CN111312415A (en) | Fault diagnosis method and device |
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 |