Reliability evaluation method for integrated energy system with dynamic multi-energy coupling and conversion

Abstract

The application discloses a kind of dynamic multi-energy coupling and conversion comprehensive energy system reliability evaluation method.Establish the multi-state reliability model of multi-energy production element considering dynamic multi-energy coupling, establish the multi-state reliability model of multi-energy conversion element considering dynamic multi-energy conversion, establish the multi-state reliability model of multi-energy transmission element considering dynamic multi-energy coupling, according to the multi-state reliability model of three kinds of elements, the multi-state reliability model of three kinds of subsystems is constructed;According to the multi-state reliability model of three kinds of subsystems, the reliability of comprehensive energy system considering multi-energy coupling and conversion is obtained by using improved general production function method, and reliability evaluation is realized.The dynamic characteristics of the comprehensive energy system can be more accurately characterized by using the multi-state model, and the reliability of the comprehensive energy system that meets the accuracy requirements is accurately calculated.

Description

Technical Field

[0001] This invention relates to a system reliability extraction method in the field of integrated energy systems, specifically a reliability assessment method for integrated energy systems that considers dynamic multi-energy coupling and conversion. Background Technology

[0002] An integrated energy system refers to a new type of integrated energy system that utilizes advanced physical information technology and innovative management models within a specific region to integrate various energy sources such as coal, oil, natural gas, electricity, and heat. This system achieves coordinated planning, optimized operation, collaborative management, interactive response, and mutual support among multiple heterogeneous energy subsystems. While meeting the diverse energy needs within the system, it effectively improves energy utilization efficiency and promotes sustainable energy development.

[0003] Reliability technology was first developed in the aerospace and electronics industries after World War II. The task of an integrated energy system is to provide users with a continuous supply of qualified energy, specifically including gas, heat, and electricity. Because various equipment within an integrated energy system, including energy coupling equipment (such as combined heat and power units, natural gas units, and combined cooling, heating, and power units), energy transmission equipment (such as urban management systems), circuit breakers, and other primary and associated secondary equipment, can experience different types of failures, thus affecting the normal operation of the integrated energy system and its ability to supply energy to users. Failures in integrated energy systems can cause varying degrees of economic losses to energy companies, users, and certain sectors of the national economy. With the accelerating pace of modernization, production and daily life are increasingly reliant on various types of gas, heat, cooling, and electricity energy, and the losses caused by the interruption of these energy sources are also growing. Therefore, integrated energy systems are required to have high reliability.

[0004] Reliability assessment involves calculating and analyzing the probabilities and consequences of possible failure states to derive a series of indicators reflecting the system's reliability level. However, in a real-world system with hundreds or even thousands of components, the number of possible failure states is enormous. Due to limitations in computation time and resources, it is impossible to assess all possible failure states in practical evaluations. Therefore, state enumeration methods only select failure states that contribute significantly to system reliability for evaluation. The most commonly used selection method is to cut off the failure severity, i.e., selecting failure states with 2 or fewer severity levels and ignoring those with higher severity levels. The advantage of this method is that the sum of probabilities of the selected states is close to 1, and the number is relatively small. However, in real-world systems, due to the different outage probabilities of components, some high-severity failures have a higher probability of occurrence than low-severity failures. Taking an IEEE-RTS system with 71 components as an example, when the components adopt a 2-state model, the number of system states considering N-3 is 57226, and the sum of probabilities is 0.95110503. In reality, the top 57,226 states with higher probabilities include 16,786 states with 0 to 3 faults and 40,440 states with 4 to 6 faults, with a sum of probabilities of 0.98976138. These high-probability fault states have high probabilities and severe consequences, significantly impacting system reliability. State selection based on the cutoff fault count ignores these high-probability faults. Therefore, in reliability analysis, the number of states selected, whether retained or deleted, greatly affects the final result. This underscores the necessity of researching rapid and accurate reliability analysis for systems.

[0005] Current reliability analysis algorithms primarily focus on power system reliability analysis. However, with the introduction of multiple coupled energy sources, power system reliability analysis that can only assess electrical energy is no longer suitable for the reliability analysis of integrated energy systems with multiple energy couplings. The reliability of multiple energy sources, such as gas, heat, cooling, and electricity, needs to be reflected simultaneously. Therefore, this invention proposes a new reliability analysis algorithm that can be used to calculate the reliability of integrated energy systems considering multiple energy couplings.

[0006] Meanwhile, with the introduction of multiple coupled energy sources, multi-energy conversion is a typical feature of integrated energy systems. Different energy sources can be transformed into other energy sources through multi-energy conversion processes, thus achieving complex coupling between energy sources. Reliability analysis of power systems that can only assess electrical energy is no longer applicable to the reliability analysis of integrated energy systems involving multi-energy conversion processes. The conversion and coupling of multiple energy sources such as gas, heat, cooling, and electricity need to be reflected in the reliability assessment simultaneously. Traditional reliability analysis algorithms cannot evaluate the reliability of integrated energy systems with multi-energy conversion. Therefore, this invention proposes a new reliability analysis algorithm that can be used to calculate the reliability of integrated energy systems considering multi-energy conversion.

[0007] Existing algorithms can be used to calculate the reliability of integrated energy systems, but these algorithms treat the operation of the integrated energy system as having two states: complete failure or perfect operation, without considering the intermediate states of the integrated energy system's operation. Therefore, due to insufficient modeling of the integrated energy system's operation, the resulting reliability model cannot accurately reflect the dynamic characteristics of the integrated energy system. This invention proposes a multi-state reliability model for integrated energy systems that considers dynamic multi-energy coupling and conversion, incorporating multiple intermediate states of the integrated energy system's operation into the system's reliability.

[0008] The shortcomings of existing technologies are summarized as follows:

[0009] Disadvantage of existing technology 1: Traditional reliability calculation algorithms mainly focus on power system reliability analysis. However, with the introduction of multiple coupled energy sources, power system reliability analysis that can only evaluate electrical energy is no longer applicable to the reliability analysis of integrated energy systems containing multiple energy conversions.

[0010] Disadvantage 2 of existing technology: Traditional reliability calculation algorithms mainly focus on power system reliability analysis. However, with the increasing complexity of the conversion process of multiple coupled energy sources, power system reliability analysis that can only evaluate electrical energy is no longer applicable to the reliability analysis of integrated energy systems containing multiple energy conversion processes.

[0011] Disadvantage 3 of existing technology: Existing technology treats the operation of integrated energy system as two states, namely complete failure or perfect operation, without considering the intermediate state of operation of integrated energy system. As a result, due to insufficient modeling of integrated energy system operation, the obtained reliability model cannot accurately reflect the dynamic characteristics of integrated energy system. Summary of the Invention

[0012] To address the shortcomings of existing technologies, this invention proposes a reliability assessment method for integrated energy systems that considers dynamic multi-energy coupling and conversion. By establishing a multi-state model, the dynamic characteristics of the integrated energy system can be more accurately characterized, and the reliability of the integrated energy system that meets the reliability accuracy requirements can be precisely obtained.

[0013] like Figure 1 As shown, the technical solution of the present invention is as follows:

[0014] Step 1: Establish a multi-state reliability model of the multi-energy production components of the integrated energy system that considers dynamic multi-energy coupling, and characterize it in the form of a vector general generating function;

[0015] Step 2: Establish a multi-state reliability model of multi-energy conversion components for a comprehensive energy system that considers dynamic multi-energy conversion, and characterize it using a matrix-based general generating function.

[0016] Step 3: Establish a multi-state reliability model of the multi-energy transmission components of the integrated energy system that considers dynamic multi-energy coupling, and characterize it in the form of a vector general generating function;

[0017] Step 4: Based on the multi-state reliability model of multi-energy production components, multi-energy transmission components, and multi-energy conversion components, construct a multi-state reliability model of the multi-energy production subsystem, multi-energy conversion subsystem, and multi-energy transmission subsystem of the integrated energy system that considers dynamic multi-energy coupling and conversion.

[0018] Step 5: Based on the multi-state reliability model of the multi-energy production subsystem, multi-energy conversion subsystem, and multi-energy transmission subsystem, the improved general production function method is used to obtain the reliability of the integrated energy system considering multi-energy coupling and conversion under different multi-energy load requirements, thus achieving reliability assessment.

[0019] In practice, reliability can be further utilized to establish reliability constraints for the structural planning and backup optimization scheduling of integrated energy systems, thereby improving the reliability of integrated energy systems.

[0020] The integrated energy system of the present invention is a multi-state system. A multi-state system is defined as a system and its components that may exhibit multiple operating levels.

[0021] In this invention, the bolded letter variables all represent vectors. The multi-energy coupling element takes into account multi-energy coupling, and the output of the integrated energy system is extended from one-dimensional output to multi-dimensional output, ensuring that multiple energy sources can be universally represented through a single output form.

[0022] Meanwhile, the multi-energy conversion element also considers multi-energy conversion, and the variables of the integrated energy system are expanded from one-dimensional variables to matrix variables, ensuring that multiple energy sources can be universally represented through matrix elements.

[0023] The integrated energy system is equivalent to a structure composed of a series connection of a multi-energy conversion subsystem and a multi-energy coupling subsystem. The multi-energy conversion subsystem is composed of multi-energy conversion elements connected in parallel, and the multi-energy coupling subsystem is composed of multi-energy coupling elements connected in parallel. The multi-energy coupling subsystem is divided into a multi-energy production subsystem and a multi-energy transmission subsystem. The multi-energy coupling elements are divided into multi-energy production elements and multi-energy transmission elements. The multi-energy production subsystem is composed of multi-energy production elements, and the multi-energy transmission subsystem is composed of multi-energy transmission elements.

[0024] Multi-energy coupling elements, the most common energy coupling devices are various multi-energy production equipment and multi-energy transmission lines. Among multi-energy coupling elements, multi-energy production elements specifically refer to multi-energy production equipment (e.g., natural gas sources), and multi-energy transmission elements specifically refer to multi-energy transmission lines (e.g., urban integrated utility tunnels). Multi-energy conversion elements specifically refer to multi-energy conversion equipment (i.e., multi-energy conversion components, the most common of which are various multi-energy conversion units, such as combined heat and power units, natural gas units, and combined cooling, heating and power units).

[0025] The functional relationships between the multi-energy production subsystem, multi-energy conversion subsystem, and multi-energy transmission subsystem follow a sequential order, equivalent to a series structure: the multi-energy production subsystem first generates various energy sources, which are then converted by the multi-energy conversion subsystem, and finally transmitted to users by the multi-energy transmission subsystem. Energy sources include electrical energy parameters, thermal energy, cooling energy, natural gas energy, etc.

[0026] The integrated energy system has multiple multi-energy coupled units operating simultaneously to generate output power. The multi-energy coupled units are connected in parallel to form a unit subsystem. Because the output power of the multi-energy coupled units is too large, the transmission capacity of a single multi-energy coupled transmission line is limited. Therefore, multiple multi-energy coupled transmission lines are set up to transmit the output power of the units simultaneously, so that the multi-energy coupled transmission lines are connected in parallel to form a line subsystem.

[0027] Within an integrated energy system, multiple multi-energy production devices must operate simultaneously to generate sufficient energy output. These multi-energy production devices are multiple multi-energy conversion devices connected in parallel to form a multi-energy production subsystem, operating simultaneously to produce output power. If the output power of a single multi-energy conversion element within the multi-energy conversion subsystem is too large, and the transmission capacity of a single multi-energy conversion element is limited, multiple multi-energy conversion elements are needed to transmit the output power simultaneously. Therefore, these multiple multi-energy conversion elements are connected in parallel to form a multi-energy transmission subsystem.

[0028] The first step is specifically as follows:

[0029] The multi-energy production equipment (including natural gas sources, etc.) in an integrated energy system are collectively referred to as multi-energy production elements. Multi-energy production elements are often used to generate various types of energy output, which is then converted into other types of energy output by multi-energy conversion equipment and transmitted to users to meet load demands.

[0030] As multi-energy production components age, their output power will dynamically decline, exhibiting a multi-state dynamic operation. The state of a multi-energy production component characterizes its operational features, and its output power has k states. For example, a natural gas source state with an ordinal number of 1 indicates that the natural gas source is completely inoperable, with an output power of 0; a natural gas source state with an ordinal number of k indicates that the natural gas source is in perfect operation, with an output power of 100% of its rated output; and a natural gas source state with an ordinal number x, x = 1 to k, indicates that the natural gas source is partially inoperable, with an output power of (x / k)% of its rated output.

[0031] The status of each multi-energy production element is defined by parameters. and w i,j This indicates that i represents the sequence number of the multi-energy production element, and j represents the state sequence number. w represents the probability that multi-energy production element i is in state j. i,j Let w represent the output power of multi-energy production element i when it is in state j; and the output power of each multi-energy production element is characterized by multiple energy parameters. The output power of any multi-energy production element can be completely characterized by V energy parameters. i,j Characterized as in This represents the output power corresponding to energy parameter v when the multi-energy production element i is in state j, where v represents the sequence number of the energy parameter; the output power of a multi-energy production element i is formed by the superposition of multiple energy parameters.

[0032] In practice, the energy parameters are specifically divided into electrical energy parameters, thermal energy parameters, and natural gas energy parameters, but are not limited to these.

[0033] The multi-state reliability model for multi-energy production components is represented by a vector general generating function, including:

[0034] Reliability of a single multi-energy production element i:

[0035]

[0036] In the formula, This represents a multi-state reliability function characterized by a general generating function for multi-energy production element i. Let i represent the probability that multi-energy production element i is in state j. The output power of multi-energy production element i in state j is represented by the z-transformation form, w i,jrepresents the output power of multi-energy production element i when it is in state j, and z represents the z transformation parameter;

[0037] The reliability of a single multi-energy production element i under the output power corresponding to a single energy parameter v is transformed from a multi-dimensional variable to a one-dimensional variable:

[0038]

[0039] In the formula, This represents the multi-state reliability function characterized by a general generating function for the multi-energy production element i under the output power corresponding to energy parameter v. This represents the output power corresponding to the energy parameter v when the multi-energy production element i is in state j.

[0040] The second step is as follows:

[0041] The multi-energy conversion equipment in an integrated energy system (including combined heat and power units, natural gas units, and combined cooling, heating and power units) is collectively referred to as multi-energy conversion elements. Multi-energy conversion elements involve multi-energy conversion processes, which refer to the conversion of one type of input energy capacity into other forms of energy. For example, in a combined heat and power unit, natural gas energy, as the input energy, undergoes a multi-energy conversion process to become both electrical energy and heat energy as output energy.

[0042] As multi-energy conversion elements age, their energy conversion capacity also decreases, and their operating state becomes multi-state. The state of a multi-energy conversion element characterizes its operating features, and its dynamic energy conversion capacity has h states. For example, a state number of 1 indicates that the multi-energy conversion element is in a completely failed state, unable to operate at all, with an output of 0; a state number of h indicates that the multi-energy conversion element is in a perfect operating state, with an output of 100% of its rated output; and a state number of x, x = 1 to h, indicates that the multi-energy conversion element is in a partially failed state, with an output of (x / h)% of its rated output.

[0043] The state of each multi-energy conversion element is represented by parameters. and C i,j This indicates that i represents the serial number of the multi-energy conversion element, and j represents the state serial number. C represents the probability that the multi-energy conversion element i is in state j. i,j The energy conversion matrix represents the energy conversion capability between the input and output energy parameters of the multi-energy conversion element i when it is in state j.

[0044] The input energy capacity of each multi-energy conversion element is characterized by V energy parameters, and the output energy output is also characterized by V energy parameters. The energy parameters represent the type of energy, such as natural gas, cold energy, heat energy, and electrical energy. For example, the input energy capacity of a multi-energy conversion element is characterized by two energy parameters, natural gas and electricity, indicating that the element inputs natural gas energy and electrical energy.

[0045] The states of multiple energy conversion elements are represented by a matrix-based energy conversion matrix. The general generating function is extended from a one-dimensional function to a matrix-represented function. The multi-state reliability model of multiple energy conversion element i is represented by a matrix-based general generating function, namely:

[0046]

[0047] In the formula, This indicates that the multi-state reliability function is characterized by a matrix-based general generating function for the multi-energy conversion element i.

[0048] The third step is as follows:

[0049] The multi-energy transmission lines (including urban integrated utility tunnels) of a comprehensive energy system are collectively referred to as multi-energy transmission elements. Multi-energy transmission elements often take the output energy from multi-energy conversion elements as their input transmission capacity, and after passing through the multi-energy transmission element, it becomes the output transmission capacity of the multi-energy transmission element and is transmitted to a distant location.

[0050] As multi-energy transmission components age, their energy transmission capacity also undergoes a dynamic decay process, exhibiting a multi-state dynamic operating state. The state of a multi-energy transmission component characterizes its operational features, and its energy transmission capacity has q states. For example, if the state ordinal number of a city integrated utility tunnel is 1, it indicates that the tunnel is in a completely failed state, unable to operate, with an output power of 0; if the state ordinal number is q, it indicates that the tunnel is in a perfect operating state, with an output power of 100% of its rated output; if the state ordinal number is x, x = 1 to q, it indicates that the tunnel is in a partially failed state, with an output power of (x / q)% of its rated output.

[0051] The status of each multi-energy transmission element is defined by parameters. and q i,j This indicates that i represents the sequence number of the multi-energy transmission element, and j represents the state sequence number. q represents the probability that the multi-energy transmission element i is in state j. i,jLet q represent the output power of multi-energy transmission element i when it is in state j; and the output power of each multi-energy transmission element is characterized by multiple energy parameters. The output power of any multi-energy transmission element can be completely characterized by V energy parameters. i,j Characterized as in This represents the output power corresponding to energy parameter v when the multi-energy transmission element i is in state j, where v represents the sequence number of the energy parameter; the output power of a multi-energy transmission element i is formed by the superposition of multiple energy parameters.

[0052] In practice, the energy parameters are specifically divided into electrical energy parameters, thermal energy parameters, and natural gas energy parameters, but are not limited to these.

[0053] The multi-state reliability model of multiple energy transmission elements is represented by a vector general generating function, including:

[0054] Reliability of a single multi-energy transmission element i:

[0055]

[0056] In the formula, This represents a multi-state reliability function characterized by a general generating function for the multi-energy transmission element i. Let i represent the probability that the multi-energy transmission element i is in state j. The output power of the multi-energy transmission element i in state j is represented by the z-transformation form, q. i,j represents the output power of multi-energy transmission element i when it is in state j, and z represents the z transformation parameter;

[0057] The reliability of a single multi-energy transmission element i under the output power corresponding to a single energy parameter v is transformed from a multi-dimensional variable to a one-dimensional variable:

[0058]

[0059] In the formula, This represents the multi-state reliability function of multiple energy transmission elements i under the output power corresponding to energy parameter v, characterized by a general generating function. This indicates the output power corresponding to the energy parameter v when the multi-energy transmission element i is in state j.

[0060] In the prior art, a one-dimensional variable is used to represent the state of a comprehensive energy system. However, in the processing of comprehensive energy systems in this invention, the state of the comprehensive energy system is represented by V energy parameters, using multi-dimensional variables. The general generating function is extended from the existing one-dimensional function to a multi-dimensional function.

[0061] The fourth step is as follows:

[0062] The multiple energy production components are connected in parallel. The sum of the output energy of each component is taken as the output energy of the multi-energy production subsystem. A multi-state reliability model of the multi-energy production subsystem considering multi-energy coupling is established as follows:

[0063]

[0064] In the formula, u s (z) represents the multi-state reliability function of a multi-energy production subsystem considering multi-energy coupling, characterized by a vector general generating function, where K represents the number of states of the multi-energy production subsystem after processing, p s,j W represents the probability that the multi-energy production subsystem is in state j. s,j This indicates that the multi-energy production subsystem is in state j, and its output energy is being produced. This represents the output energy of a multi-energy production subsystem considering energy parameter v; j i This represents the state number of the i-th multi-energy production element, where i is the number of n elements contained in the multi-energy production subsystem. s The serial number of each multi-energy production component, i.e. n s w represents the number of multi-energy production components contained in the multi-energy production subsystem. i,ji This indicates that the i-th multi-energy production element is in state j. i Energy output at that time This indicates that the i-th multi-energy production element is in state j. i The probability of;

[0065] The multiple energy conversion elements are connected in parallel. The sum of the energy conversion capabilities of each element is taken as the energy conversion capability of the multi-energy conversion subsystem. A multi-state reliability model for the multi-energy conversion subsystem considering multiple energy conversion is established as follows:

[0066]

[0067] In the formula, u L (z) represents the multi-state reliability function of a multi-energy conversion subsystem considering multi-energy conversion, characterized by a matrix general generating function, where H represents the number of states of the multi-energy conversion subsystem after simplification, and p L,j C represents the probability that the multi-energy conversion subsystem is in state j. L,j The energy conversion matrix represents the energy conversion matrix of the multi-energy conversion subsystem in state j; j i This represents the state number of the i-th multi-energy conversion element, where i is the number of n elements contained in the multi-energy conversion subsystem. L The serial number of each energy conversion element, i.e. n L C represents the number of multi-energy conversion elements contained in the multi-energy conversion subsystem. i,ji This indicates that the i-th multi-energy conversion element is in state j. i Energy conversion matrix at time, This indicates that the i-th multi-energy conversion element is in state j. i The probability of.

[0068] The multiple energy transmission elements are connected in parallel. The sum of the energy transmission capabilities of each element is taken as the output power of the multi-energy conversion subsystem. A multi-state reliability model of the multi-energy transmission subsystem considering multi-energy coupling is established as follows:

[0069]

[0070] In the formula, u c (z) represents the multi-state reliability function of a multi-energy conversion subsystem considering multi-energy coupling, characterized by a vector general generating function. Q represents the number of states of the multi-energy transmission subsystem after processing. p c,j Q represents the probability that the multi-energy transmission subsystem is in state j. c,j This indicates that the multi-energy transmission subsystem is in state j, and its output transmission capacity is... This represents the output energy of a multi-energy transmission subsystem considering energy parameter v; j i This represents the state number of the i-th multi-energy transmission element, where i is the number of n elements contained in the multi-energy transmission subsystem. c The serial number of each energy transmission element, i.e. n c q represents the number of multi-energy conversion elements contained in the multi-energy transmission subsystem. i,ji This indicates that the i-th multi-energy transmission element is in state j. i Output transmission power at that time This indicates that the i-th multi-energy transmission element is in state j. i The probability of.

[0071] The fifth step is as follows:

[0072] The first four steps yield multi-state reliability models for the multi-energy production subsystem and the multi-energy conversion subsystem. Since the multi-energy conversion process refers to the conversion of one type of input energy capacity into other output energy output through the multi-energy conversion process, the input energy capacity of the entire multi-energy conversion subsystem is obtained based on the energy conversion capability of the multi-energy conversion subsystem, and then the output energy output after passing through the multi-energy production subsystem and the multi-energy conversion subsystem is calculated.

[0073] S51. Based on the series connection of the multi-energy production subsystem and the multi-energy conversion subsystem, establish the following output energy model after passing through the multi-energy production subsystem and the multi-energy conversion subsystem:

[0074]

[0075] In the formula, u outz (z) represents the multi-state reliability function, characterized by a vector general generating function, representing the output energy after passing through the multi-energy production subsystem and the multi-energy conversion subsystem. W outz,j This represents the output energy output in state j after passing through the multi-energy production subsystem and the multi-energy conversion subsystem, characterized by V energy parameters, p outz,j Indicates the output energy (W) outz,j The corresponding probability is p o u,tz ; G represents the output energy power corresponding to energy parameter v in state j, and G represents the number of states contained in the multi-energy production subsystem and multi-energy conversion subsystem after the sorting.

[0076] S52. Based on the fact that the multi-energy conversion subsystem and the multi-energy transmission subsystem are connected in series, and the output energy of the multi-energy conversion subsystem is equal to the input transmission capacity of the multi-energy transmission subsystem, the following multi-state reliability model of the integrated energy system considering the multi-energy transmission subsystem is established on the basis of the output energy model:

[0077]

[0078] In the formula, This represents the multi-state reliability function of the integrated energy system considering three subsystems, characterized by a vector general generating function. M represents the total number of states in the integrated energy system after the fusion and rearrangement of the three subsystems. p sys,j W represents the probability that the integrated energy system is in state j. sys,j This represents the output energy of a comprehensive energy system characterized by V energy parameters in state j. This indicates the output energy of the integrated energy system in state j under only energy parameter v.

[0079] S53. Using the multi-state reliability model of the integrated energy system, the following relationship is obtained, and then the probability p is calculated. sys,j and output energy W sys,j :

[0080]

[0081]

[0082] S54, According to probability p sys,j and output energy W sys,j The output of the integrated energy system to meet the multi-energy load demand is calculated using the following formula. The sum of probabilities corresponding to the system states Reliability of a comprehensive energy system that considers multiple energy conversions and couplings:

[0083]

[0084]

[0085] In the formula, Given the known multi-energy load demand, w *v This represents the load demand under the output power corresponding to the energy parameter v; The function representing the comparison between multi-energy load demand and output power is given if and only if the output power W under each energy parameter is given. sys,j All greater than or equal to When, function Select 1, otherwise function All values ​​are set to 0.

[0086] The multi-energy load demand and output comparison function Represented as:

[0087]

[0088] In the formula, ∧ represents the logical operation and sum.

[0089] This invention is applied to the reliability calculation of integrated energy systems considering multi-energy coupling and conversion. First, a multi-state reliability model for integrated energy systems considering dynamic multi-energy coupling is proposed. Second, a multi-state reliability model for integrated energy systems considering dynamic multi-energy conversion is proposed. Then, an improved general generating function method is used to perform reliability analysis on the multi-state reliability model of integrated energy systems considering dynamic multi-energy coupling and multi-energy conversion.

[0090] The beneficial effects of this invention are:

[0091] The integrated energy system multi-state reliability model of the present invention integrates multi-energy conversion into the system state, corrects the one-dimensional state into a matrix state, and also integrates multi-energy coupling into the system state, correcting the one-dimensional state into a multi-dimensional state.

[0092] The multi-state reliability assessment method for integrated energy systems of the present invention takes into account multiple intermediate states of the integrated energy system operation into the system reliability, so that the obtained reliability model accurately reflects the dynamic characteristics of the integrated energy system, and thus accurately characterizes and calculates the reliability of the integrated energy system considering dynamic multi-energy conversion and coupling. Attached Figure Description

[0093] Figure 1 This is a flowchart of the present invention.

[0094] Figure 2 This is a schematic diagram of the equivalent system structure of an embodiment. Detailed Implementation

[0095] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0096] The embodiments of the present invention are as follows:

[0097] Step 1: Establish a multi-state reliability model of the multi-energy production components of the integrated energy system that considers dynamic multi-energy coupling, and represent the multi-state reliability model of the multi-energy production components in the form of a vector general generating function.

[0098] In the integrated energy system of this embodiment, its multi-energy production subsystem comprises 10 identical natural gas sources. The entire integrated energy system is characterized by three energy parameters: natural gas (gas), heat (heat), and electricity (elec), with the unit being megawatts (MW).

[0099] A single natural gas source has three states. The multi-state reliability model of a single natural gas source, characterized by a vector general generating function, is as follows:

[0100]

[0101] Step 2: Establish a multi-state reliability model of the multi-energy conversion components of the integrated energy system that considers dynamic multi-energy conversion, and characterize the multi-state reliability model of the multi-energy conversion components in the form of a matrix-based general generating function.

[0102] In the integrated energy system of this embodiment, its multi-energy conversion subsystem comprises 10 identical combined heat and power (CHP) units. The entire integrated energy system is characterized by three energy parameters: natural gas (gas), heat (heat), and electricity (elec), with the unit being megawatts (MW).

[0103] A single cogeneration unit has three states. The multi-state reliability model of a single cogeneration unit, characterized by a matrix general generating function, is as follows:

[0104]

[0105] Step 3: Establish a multi-state reliability model of the multi-energy transmission components of the integrated energy system that considers dynamic multi-energy coupling, and characterize the multi-state reliability model of the multi-energy transmission components in the form of a vector general generating function.

[0106] In the integrated energy system of this embodiment, its multi-energy transmission subsystem includes 10 identical urban integrated utility tunnels. The entire integrated energy system is characterized by three energy parameters: natural gas (gas), heat (heat), and electricity (elec), with the unit being megawatts (MW).

[0107] A single integrated energy system has three states. The multi-state reliability model of a single integrated energy system, characterized by a vector universal generating function, is as follows:

[0108]

[0109] Step 4: Construct a multi-state reliability model for the multi-energy production, multi-energy conversion, and multi-energy production and transmission subsystems of an integrated energy system that considers dynamic multi-energy coupling and conversion;

[0110] Since the components of each subsystem are connected in parallel, the multi-state model of each subsystem is as follows:

[0111] Reliability model of multi-energy production subsystem:

[0112]

[0113] Model of multi-energy conversion subsystem:

[0114]

[0115] Reliability model of multi-energy transmission subsystem:

[0116]

[0117] Step 5: Calculate the reliability of the integrated energy system considering multi-energy coupling and conversion to meet different multi-energy load demands using the improved general production function method.

[0118] Multi-energy load demand is That is, at least 5MW of thermal energy and 5MW of electrical energy are required for the system to operate reliably. Based on the multi-state reliability model of the integrated energy system considering dynamic multi-energy conversion and coupling, the following is provided:

[0119]

[0120] Based on the multi-energy load demand, the reliability of the integrated energy system can be calculated to be 0.9984.

Claims

1. A reliability assessment method for a dynamic multi-energy coupling and conversion integrated energy system, characterized in that: Step 1: Establish a multi-state reliability model of the multi-energy production components of the integrated energy system that considers dynamic multi-energy coupling, and characterize it in the form of a vector general generating function; Step 2: Establish a multi-state reliability model of multi-energy conversion components for a comprehensive energy system that considers dynamic multi-energy conversion, and characterize it using a matrix-based general generating function. Step 3: Establish a multi-state reliability model of the multi-energy transmission components of the integrated energy system that considers dynamic multi-energy coupling, and characterize it in the form of a vector general generating function; Step 4: Based on the multi-state reliability models of multi-energy production components, multi-energy transmission components, and multi-energy conversion components, construct multi-state reliability models for the multi-energy production subsystem, multi-energy conversion subsystem, and multi-energy transmission subsystem. Step 5: Based on the multi-state reliability models of the multi-energy production subsystem, multi-energy conversion subsystem, and multi-energy transmission subsystem, the improved general production function method is used to obtain the reliability of the integrated energy system considering multi-energy coupling and conversion under different multi-energy load requirements, thereby achieving reliability assessment; The integrated energy system is equivalent to a structure consisting of a series connection of a multi-energy conversion subsystem and a multi-energy coupling subsystem. The multi-energy conversion subsystem is composed of multiple energy conversion elements connected in parallel, and the multi-energy coupling subsystem is composed of multiple energy coupling elements connected in parallel. The multi-energy coupling subsystem is divided into a multi-energy production subsystem and a multi-energy transmission subsystem. The multi-energy coupling element is divided into a multi-energy production element and a multi-energy transmission element. The multi-energy production subsystem is composed of multi-energy production elements, and the multi-energy transmission subsystem is composed of multi-energy transmission elements. The first step is specifically as follows: The status of each multi-energy production element is defined by parameters. and express, Let i represent the probability that multi-energy production element i is in state j. This indicates the output power of multi-energy production element i when it is in state j; Furthermore, the output power of each multi-energy production element is characterized by multiple energy parameters, and the output power of multi-energy production element i when it is in state j is... Characterized as ,in This indicates the output power corresponding to energy parameter v when the multi-energy production element i is in state j, where v represents the sequence number of the energy parameter. The multi-state reliability model for multi-energy production components is represented by a vector general generating function, including: Reliability of a single multi-energy production element i: ； In the formula, This represents a multi-state reliability function characterized by a general generating function for multi-energy production element i. Let i represent the probability that multi-energy production element i is in state j. This represents the output force of the multi-energy production element i in state j, expressed using the z-transformation. represents the output power of multi-energy production element i when it is in state j, and z represents the z transformation parameter; Reliability of a single multi-energy production element i under the output power corresponding to a single energy parameter v: ； In the formula, This represents the multi-state reliability function characterized by a general generating function for the multi-energy production element i under the output power corresponding to energy parameter v. This indicates the output power corresponding to energy parameter v when the multi-energy production element i is in state j; The second step is as follows: The state of each multi-energy conversion element is represented by parameters. and express, Let i represent the probability that the multi-energy conversion element i is in state j. The energy conversion matrix represents the energy conversion capability between the input and output energy parameters of the multi-energy conversion element i when it is in state j. The multi-state reliability model of the multi-energy conversion element i is characterized by a matrix-based general generating function, namely: ； In the formula, This indicates that the multi-energy conversion element i is characterized by a multi-state reliability function based on a matrix-based general generating function; The third step is as follows: The status of each multi-energy transmission element is defined by parameters. and express, Let i represent the probability that the multi-energy transmission element i is in state j. This represents the output power of multi-energy transmission element i when it is in state j; and the output power of each multi-energy transmission element is characterized by multiple energy parameters. Characterized as ,in This indicates the output power corresponding to energy parameter v when the multi-energy transmission element i is in state j, where v represents the sequence number of the energy parameter. The multi-state reliability model of multiple energy transmission elements is represented by a vector general generating function, including: Reliability of a single multi-energy transmission element i: ； In the formula, This represents a multi-state reliability function characterized by a general generating function for the multi-energy transmission element i. Let i represent the probability that the multi-energy transmission element i is in state j. This represents the output power of the multi-energy transmission element i in state j, expressed as a z-transformation. represents the output power of multi-energy transmission element i when it is in state j, and z represents the z transformation parameter; Reliability of a single multi-energy transmission element i under the output power corresponding to a single energy parameter v: ； In the formula, This represents the multi-state reliability function of multiple energy transmission elements i under the output power corresponding to energy parameter v, characterized by a general generating function. This indicates the output power corresponding to energy parameter v when the multi-energy transmission element i is in state j; The fourth step is as follows: Using the sum of the output energy of each multi-energy production element as the output energy of the multi-energy production subsystem, a multi-state reliability model of the multi-energy production subsystem considering multi-energy coupling is established as follows: ； In the formula, This represents a multi-state reliability function for a multi-energy production subsystem considering multi-energy coupling, characterized by a vector general generating function, where K represents the number of states in the streamlined multi-energy production subsystem. Let represent the probability that the multi-energy production subsystem is in state j. This indicates that the multi-energy production subsystem is in state j, and its output energy is being produced. , This represents the output energy of a multi-energy production subsystem considering energy parameter v. This represents the state number of the i-th multi-energy production element, where i is the number of elements contained in the multi-energy production subsystem. The serial number of each multi-energy production component, i.e. , This indicates the number of multi-energy production components contained in the multi-energy production subsystem. This indicates that the i-th multi-energy production element is in state i. Energy output at that time This indicates that the i-th multi-energy production element is in a certain state. The probability of; Using the sum of the energy conversion capabilities of each multi-energy conversion element as the energy conversion capability of the multi-energy conversion subsystem, a multi-state reliability model for the multi-energy conversion subsystem considering multi-energy conversion is established as follows: ； In the formula, This represents the multi-state reliability function of a multi-energy conversion subsystem considering multiple energy conversions, characterized by a matrix general generating function, where H represents the number of states of the multi-energy conversion subsystem after simplification. Let represent the probability that the multi-energy conversion subsystem is in state j. The energy conversion matrix represents the energy conversion matrix of the multi-energy conversion subsystem in state j; This represents the state number of the i-th multi-energy conversion element, where i is the number of elements contained in the multi-energy conversion subsystem. The serial number of each energy conversion element, i.e. , This indicates the number of multi-energy conversion elements contained in the multi-energy conversion subsystem. This indicates that the i-th multi-energy conversion element is in state i. Energy conversion matrix at time, This indicates that the i-th multi-energy conversion element is in a certain state. The probability of; Using the sum of the energy transmission capabilities of each multi-energy transmission element as the output transmission capacity of the multi-energy conversion subsystem, a multi-state reliability model of the multi-energy transmission subsystem considering multi-energy coupling is established as follows: ； In the formula, This represents the multi-state reliability function of a multi-energy conversion subsystem considering multi-energy coupling, characterized by a vector general generating function, where Q represents the number of states of the multi-energy transmission subsystem after processing. Let represent the probability that the multi-energy transmission subsystem is in state j. This indicates that the multi-energy transmission subsystem is in state j, and its output transmission capacity is... , This represents the output energy of a multi-energy transmission subsystem considering energy parameter v. This represents the state number of the i-th multi-energy transmission element, where i is the number of elements included in the multi-energy transmission subsystem. The serial number of each energy transmission element, i.e. , This indicates the number of multi-energy conversion elements contained in the multi-energy transmission subsystem. This indicates that the i-th multi-energy transmission element is in state i. Output transmission power at that time This indicates that the i-th multi-energy transmission element is in a certain state. The probability of; The fifth step is as follows: S51. Based on the series connection of the multi-energy production subsystem and the multi-energy conversion subsystem, establish the following output energy model after passing through the multi-energy production subsystem and the multi-energy conversion subsystem: ； In the formula, This represents a multi-state reliability function characterized by a vector general generating function, representing the output energy after passing through multiple energy production subsystems and multiple energy conversion subsystems. This represents the output energy output in state j after passing through the multi-energy production subsystem and the multi-energy conversion subsystem, characterized by V energy parameters. Indicates the output of energy and power. The corresponding probability; , G represents the output energy output corresponding to energy parameter v in state j, and G represents the number of states contained in the multi-energy production subsystem and the multi-energy conversion subsystem. S52. Based on the fact that the multi-energy conversion subsystem and the multi-energy transmission subsystem are connected in series, and the output energy of the multi-energy conversion subsystem is equal to the input transmission capacity of the multi-energy transmission subsystem, the following multi-state reliability model of the integrated energy system considering the multi-energy transmission subsystem is established on the basis of the output energy model: ； In the formula, Let M represent the multi-state reliability function of the integrated energy system considering three subsystems, characterized by a vector general generating function, where M represents the total number of states of the integrated energy system after processing. Let represent the probability that the integrated energy system is in state j. This represents the output energy of a comprehensive energy system characterized by V energy parameters in state j. , This indicates the output energy of the integrated energy system in state j under only energy parameter v. S53. Using the multi-state reliability model of the integrated energy system, the following relationships are obtained, and then the probabilities are calculated. and output energy : ； S54, According to probability and output energy The output of the integrated energy system to meet the multi-energy load demand is calculated using the following formula. The sum of probabilities corresponding to the system states As a measure of the reliability of an integrated energy system: ； ； In the formula, To meet the needs of multi-energy loads, This represents the load demand under the output power corresponding to the energy parameter v; This function represents a comparison between demand and output of multi-energy loads. The multi-energy load demand and output comparison function Represented as: ； In the formula, This represents logical operations and.

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