Energy supply recovery decision optimization method for electricity-gas integrated energy system

Abstract

The invention discloses an energy supply recovery decision optimization method for an electricity-gas integrated energy system, and belongs to the field of integrated energy systems. Comprising the following steps: on the basis of comprehensive demand response of a load in the electricity-gas comprehensive energy system, by taking maximum recovery net income in a system energy supply recovery process as a target, constructing an electricity-gas comprehensive energy system energy supply recovery decision target function and corresponding comprehensive demand response constraint, gas turbine gas-electricity conversion constraint, power distribution network constraint and gas distribution network constraint; and carrying out optimization solution on the objective function with the comprehensive demand response constraint, the gas turbine gas-electricity conversion constraint, the power distribution network constraint and the gas distribution network constraint, and determining an energy supply recovery decision scheme of the electricity-gas comprehensive energy system. By optimizing the regulation and control scheme of the load and the operation sequence of the equipment in the electricity-gas comprehensive energy system, energy supply resources in the system are fully utilized, and the method has remarkable help to the reasonability and effectiveness of energy supply recovery of the electricity-gas comprehensive energy system.

Description

Technical Field

[0001] The invention belongs to the field of integrated energy systems and relates to a method for optimizing the decision-making of energy supply restoration in an electric-gas integrated energy system. Background Art

[0002] Currently, the decision-making objectives and objects of power system power supply restoration research only target a single power system. For coupling devices with energy interaction in other energy systems, such as gas turbines and electric drive compressor stations, power supply restoration decisions are made according to their typical or rated operating conditions. Therefore, the supply and demand responses of other energy systems cannot be accurately characterized, and the decision-making results will lose practical significance or cannot be implemented at all.

[0003] In the research on energy supply restoration in electric-gas integrated energy systems, a steady-state model of the gas system is often used. The steady-state model of the gas system is often used in the scheduling process with a large time interval and can only reflect the relationship between the gas flow rate in the pipeline and the gas pressure at both ends of the node. When using this model, it is necessary to determine a suitable decision-making step according to the actual operation of the gas system. If the step is too small, the actual flow rate and pressure of the pipeline will not reach the planned value, while if the step is too large, the system restoration efficiency will be reduced. The situation during the system restoration process is complex and changeable. Using the steady-state model of the gas system to make restoration decisions according to the determined decision-making step will surely not be able to well characterize the changes in pipeline flow rate and pressure during the restoration process.

[0004] Most of the existing restoration control research uses transferable or reducible loads within a single energy system to match the available energy of the system. Its essence is to use the load-load spatio-temporal coupling within a single energy system to increase the energy regulation ability. However, in an electric-gas integrated energy system, the energy demand of user terminals can be obtained from the electric and gas energy systems respectively through redundant energy-consuming devices. Its essence is the load-load spatio-temporal coupling between different energy systems. If the form of load participation in demand response is further increased, and the source-load coupling of the electric and gas systems, the load-load coupling within a single energy system, and the load-load coupling between the electric and gas systems are utilized, it will be able to effectively promote the exertion of the load collaborative regulation ability during the restoration process. Summary of the Invention

[0005] The purpose of the invention is to overcome the deficiencies in the prior art and provide a method for optimizing the decision-making of energy supply restoration in an electric-gas integrated energy system, which can improve the efficiency and rationality of energy supply restoration in the electric-gas integrated energy system.

[0006] To achieve the above purpose, the invention is implemented by the following technical solutions:

[0007] The invention provides a method for optimizing the decision-making of energy supply restoration in an electric-gas integrated energy system, including:

[0008] Based on the integrated demand response of loads in the electric-gas integrated energy system, with the goal of maximizing the net recovery benefit during the system's energy supply restoration process, a decision-making objective function for the energy supply restoration of the electric-gas integrated energy system is constructed.

[0009] The integrated demand response constraints, gas turbine gas-electric conversion constraints, distribution network constraints, and gas distribution network constraints of the decision-making objective function for the energy supply restoration of the electric-gas integrated energy system are established.

[0010] The decision-making objective function for the energy supply restoration of the electric-gas integrated energy system with the integrated demand response constraints, gas turbine gas-electric conversion constraints, distribution network constraints, and gas distribution network constraints is optimized and solved to determine the decision-making plan for the energy supply restoration of the electric-gas integrated energy system.

[0011] Furthermore, the integrated demand response of loads in the electric-gas integrated energy system is: the active response behavior of loads in the electric-gas integrated energy system under the action of incentives or compensations, including:

[0012] Loads that can be curtailed, which are energy-consuming loads that can interrupt the end-use energy demand during a certain period.

[0013] Loads that can be shifted, which are energy-consuming loads that can transfer the end-use energy demand during a certain period to other periods in the same energy system.

[0014] Loads that can be substituted, which are energy-consuming loads that can substitute the end-use energy demand during a certain period by other energy systems through redundant energy-consuming equipment.

[0015] The energy consumption interrupted by the load that can be substituted is the substituted quantity, and the energy increased in supply by other energy systems is the substituted quantity. The calculation formula for the substitution coefficient between the substituted quantity and the substituted quantity is:

[0016]

[0017] Among them, is the substitution coefficient of converting electrical energy to gas energy at node g in time step t; is the substitution coefficient of converting gas energy to electrical energy at node i in time step t; is the electro-thermal efficiency at node i in time step t; is the gas-thermal efficiency at node g in time step t; ρ is the density of natural gas, W G is the calorific value of natural gas;

[0018] In the electric-gas integrated energy system, the quantity of the end-use energy demand of the power system load substituted by the natural gas system is the gas load substitution quantity of the electric load, and the quantity of the end-use energy demand of the natural gas system load substituted by the power system is the electric load substitution quantity of the gas load.

[0019] Furthermore, the decision-making objective function for the energy supply restoration of the integrated electricity-gas energy system is as follows:

[0020] max(F - C int - C shift - C replace )

[0021] where F is the restoration revenue of the integrated electricity-gas energy system; C int is the compensation cost for the integrated electricity-gas energy system to implement load curtailment for participating in the integrated demand response, C shift is the compensation cost for the integrated electricity-gas energy system to implement load transfer for participating in the integrated demand response, C replace is the compensation cost for the integrated electricity-gas energy system to implement load substitution for participating in the integrated demand response;

[0022] The calculation formulas for F, C int , C shift and C replace are as follows:

[0023]

[0024]

[0025] where is the set of electrical load nodes in the distribution network; is the set of load nodes in the gas distribution network; Δt is the step size of the observation time step; T is the total number of observation time steps, and the total number of observation time steps is the ratio of the recovery time required by the system with the longer recovery time in the power system and the natural gas system in the integrated electricity-gas energy system to the step size of the observation time step; is the weight of load node i at time step t; indicates whether the electrical load of node i is restored to power at time step t, taking the value of 1 for restored power supply and 0 for non-restored power supply; is the electricity quantity to be restored at node i at time step t after the load participates in the integrated demand response; is the curtailed electricity quantity in the load of node i at time step t, is the transferred-in electricity quantity in the load of node i at time step t, is the transferred-out electricity quantity in the load of node i at time step t, is the electricity quantity replaced by gas in the load of node i at time step t; is the electrical load substitution quantity of the gas load of node i at time step t; μ E is the electricity price; is the unit compensation price for the curtailed electricity quantity of the electrical load, is the unit compensation price for the transferred-out electricity quantity of the electrical load, is the unit compensation price for the replaced electricity quantity of the electrical load; is the weight of the gas load node i at time step t; is whether the gas load of node g is restored to supply gas at time step t. The value of 1 indicates that the gas supply is restored, and the value of 0 indicates that the gas supply is not restored; is the volume of natural gas to be restored at node i at time step t after the load participates in the integrated demand response; is the volume of the reduced gas load at node g at time step t, is the volume of the transferred-in gas load at node g at time step t, is the volume of the transferred-out gas load at node g at time step t, is the volume of the gas load replaced by electricity at node g at time step t; is the gas load substitution amount of the electric load at node g at time step t; μ G is the gas price; is the unit compensation price for the reduced amount of the gas load, is the unit compensation price for the transferred-out amount of the gas load, is the unit compensation price for the substituted amount of the gas load.

[0026] Furthermore, the integrated demand response constraint includes an electric load demand response constraint and a gas load demand response constraint;

[0027] The electric load demand response constraint includes:

[0028]

[0029] where H is an infinitely large positive number; P i,t is the planned demand power of node i at time step t; is the proportion of the transferable electric load contracted by node i at time step t to the planned demand power, is the proportion of the reducible electric load contracted by node i at time step t to the planned demand power, is the proportion of the substitutable electric load contracted by node i at time step t to the planned demand power; is the reduced amount of the reducible electric load of node i at time step t; is the substituted amount of the substitutable electric load of node i at time step t; is the substituted amount of the substitutable gas load of node g at time step t; is the transferred amount of the transferable electric load of node i at time step t, When it is greater than 0, it indicates the transferred-out amount, When it is less than 0, it indicates the transferred-in amount; is the electric load substitution amount of the gas load of node i at time step t; is the power demand of node i at time step t after the load participates in the integrated demand response; It is the flag bit for the transfer in and out of the electrical load. A value of 1 indicates the transfer out of the electrical load, and a value of 0 indicates the transfer in of the electrical load; Etype = {shift, int, replace, GL2PL};

[0030] The gas load demand response constraints include:

[0031]

[0032] Among them, M g,t is the planned demand flow of node g at time step t; is the proportion of the transferable gas load contracted by node g at time step t to the planned demand power, is the proportion of the reducible gas load contracted by node g at time step t to the planned demand power, is the proportion of the substitutable gas load contracted by node g at time step t to the planned demand power; is the reduced amount of the reducible gas load of node g at time step t; is the transfer amount of the transferable gas load of node g at time step t, When it is greater than 0, it represents the transferred out amount, When it is less than 0, it represents the transferred in amount; is the gas load substitution amount of the electrical load of node g at time step t; is the flow demand of node g at time step t after adjustment through integrated demand response; is the flag bit for the transfer in and out of the gas load. A value of 1 indicates the transfer out of the gas load, and a value of 0 indicates the transfer in of the gas load; Gtype = {shift, int, replace, PL2GL}.

[0033] Furthermore, the gas-electric conversion constraints of the gas turbine are:

[0034]

[0035] Among them, is the set of nodes equipped with gas turbines in the distribution network; is the set of gas distribution network nodes connected to the intake port of the gas turbine, is the active power output by the gas turbine of node i at time step t; k i is the energy conversion parameter output by the gas turbine of node i at time step t; is the start-stop state of the gas turbine; is the upper limit of the gas intake flow of the gas turbine configured at node g, is the lower limit of the gas intake flow of the gas turbine configured at node g.

[0036] Further, when the power supply of the distribution network in the integrated electricity-gas energy system is restored, the power supply is restored step by step starting from the energized area or a power source with self-starting ability, and finally one or more energized areas that can operate independently are formed;

[0037] The energized area division model is as follows:

[0038]

[0039]

[0040] Among them, is the set of energized areas; is the set of distribution network nodes; is the set of distribution network branches; is the restoration status of node i at time step t in energized area m, is the restoration status of the load carried by node i at time step t in energized area m, is the restoration status of branch ij at time step t in energized area m; and both take the value of 1 indicating restored and 0 indicating not restored;

[0041] Suppose in the distribution network, the node set Among them, is the set of nodes configured with power sources; is the set of nodes configured with power sources with self-starting ability; is the set of nodes configured with power sources without self-starting ability;

[0042] The topological structure model of the distribution network in the integrated electricity-gas energy system is as follows:

[0043]

[0044] In the formula, is the restoration status of branch ij at time step t, taking the value of 1 indicating the branch is restored and 0 indicating not restored; is the restoration status of the node configured with a power source at time step t; is the set of injection branches of node i; is the set of outflow branches of node i; H is an infinitely large positive number; is the virtual output of the power source with self-starting ability, The value of is a positive integer; is the virtual power flow of the injection branch of node i, The value of is an integer; is the virtual power flow of the outflow branch of node i, The value of is an integer.

[0045] Furthermore, the distribution network constraints include one or more of the power source constraints with self-starting ability, the power source constraints without self-starting ability, the power flow constraints, the load power supply state constraints, the transient frequency constraints, and the branch restoration time constraints.

[0046] Furthermore, the power source constraints with self-starting ability include:

[0047]

[0048] Among them, P i B,max The upper limit of the active power output of the power source with self-starting ability configured for node i; P i B,min The lower limit of the active power output of the power source with self-starting ability configured for node i; The upper limit of the reactive power output of the power source with self-starting ability configured for node i; The lower limit of the active power output of the power source with self-starting ability configured for node i; The active power output of the power source with self-starting ability configured for node i at time step t; The reactive power output of the power source with self-starting ability configured for node i at time step t; ΔP i B,down And ΔP i B,up The ramp constraint of the power source with self-starting ability configured for node i;

[0049] The power source constraints without self-starting ability include:

[0050]

[0051] Among them, The restoration state of the power source without self-starting ability configured for node i at time step t within the energized domain m; The restoration state of the power source without self-starting ability configured for node i at time step t in the distribution network; And Both take a value of 1 indicating the restoration of the power source without self-starting ability and a value of 0 indicating the non-restoration of the power source without self-starting ability; P i NB,max The upper limit of the active power output of the power source without self-starting ability configured for node i; P i NB,min The lower limit of the active power output of the power source without self-starting ability configured for node i; The upper limit of the reactive power output of the power source without self-starting ability configured for node i; The lower limit of the reactive power output of the power source without self-starting ability configured for node i; ΔP i NB,downand ΔP i NB,up Ramp constraint of the non-self-starting power supply configured for node i;

[0052] The power flow constraints include:

[0053]

[0054] where P ij,t is the active power of branch ij at time step t; Q ij,t is the active power of branch ij at time step t; is the active power obtained by the object to be restored at node i at time step t; is the active power obtained by the object to be restored at node i at time step t; is the active power injected into node i at time step t; is the reactive power injected into node i at time step t; r ij is the resistance of branch ij x ij is the reactance of branch ij; l ij,t is the square of the current of branch ij at time step t; U i,t is the square of the voltage of node i at time step t; is the maximum apparent power that can pass through branch ij; is the square of the maximum voltage of node i; is the square of the minimum voltage of node i; is the square of the maximum current that can pass through branch ij; is the starting power required for the non-self-starting power supply of node i at time step t; σ i,t is the reactive power demand factor of node i at time step t;

[0055] The load power supply state constraint is:

[0056]

[0057] The transient frequency constraint is:

[0058]

[0059] where ξ is the proportion of the load that allows single-time connection or disconnection;

[0060] The branch restoration time constraint is:

[0061] Let the observation time step required for branch restoration be Then the sum of the observation time steps required for branch restoration within the energized area i needs to be less than or equal to the current observation time step:

[0062]

[0063] Furthermore, the gas distribution network constraint includes dynamic power flow constraint and / or gas source output constraint.

[0064] Furthermore, in the integrated electricity-gas energy system, the gas distribution network is composed of natural gas pipelines, and the dynamic power flow constraint includes: air pressure and gas flow rate constraints in the natural gas pipelines, node flow balance constraints of the natural gas pipelines, and node air pressure constraints of the natural gas pipelines;

[0065] The mathematical model of the isothermal flow of natural gas along the pipeline is:

[0066]

[0067] p = c 2 ρ

[0068] where p is the pipeline pressure; λ is the pipeline friction coefficient; ρ is the natural gas density; A is the pipeline cross-sectional area; c is the speed of sound of the gas;

[0069] The mathematical model is converted into a system of linear equations by using the Wendroff difference scheme to obtain the air pressure and gas flow rate constraints in the natural gas pipeline:

[0070]

[0071] where is the set of pipelines of the gas distribution network; is the set of nodes of the gas distribution network; A gh is the cross-sectional area of pipeline gh; L gh is the pipeline length; is the average flow velocity of natural gas in pipeline gh; D gh is the inner diameter of pipeline gh; ρ g,t is the natural gas density at node g at time step t; M g,t is the natural gas pressure at node g at time step t; p g,t is the natural gas mass flow rate at node g at time step t;

[0072] Assuming that the cross-sectional areas of all natural gas pipelines are equal, the node flow balance constraint of the natural gas pipeline is:

[0073]

[0074] where is the injection flow rate at node g at time step t; is the gas acquisition flow rate of the object to be restored at node g at time step t; is the gas acquisition flow rate of the gas turbine configured at node g;

[0075] The node air pressure constraint of the natural gas pipeline is:

[0076]

[0077] The gas source output constraint includes:

[0078]

[0079] wherein, is the set of nodes where the gas distribution network obtains gas from the superior gas network; is the gas acquisition flow rate of node g at time step t; is the maximum value of the gas acquisition flow rate of node g; is the minimum value of the gas acquisition flow rate of node g; is the set value of the outlet pressure of node g.

[0080] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0081] (1) The power supply restoration decision optimization method for the integrated electricity-gas energy system provided by the present invention comprehensively considers the multi-energy spatio-temporal coupling characteristics between the power system and the natural gas system to establish the comprehensive demand response constraint and the gas-electricity conversion constraint in the system power supply restoration process. It comprehensively considers the parallel restoration process of the power system to establish a charged domain division model and a topological structure model of the distribution network. In view of the energy transmission rate difference between the power system and the natural gas system, a steady-state model is respectively used to model the power system to establish the distribution network constraint, and a transient model is used to model the natural gas system to establish the gas distribution network constraint. Finally, the power supply restoration decision model of the integrated electricity-gas energy system is converted into a mixed integer linear programming model, and a commercial solver is used for solving to obtain the regulation scheme of the load and the operation sequence of the equipment in the optimized integrated electricity-gas energy system, which can make full use of the energy supply resources in the integrated electricity-gas energy system and is significantly helpful for the rationality and effectiveness of the power supply restoration of the integrated electricity-gas energy system.

[0082] (2) The comprehensive demand response proposed by the present invention expands the load demand interval from the spatio-temporal dimension through the curtailable load, shiftable load and substitutable load, and increases the solution space of the power supply restoration decision of the integrated electricity-gas energy system.

[0083] (3) The dynamic power flow constraint of natural gas proposed by the present invention can depict the changes in the gas flow rate and gas pressure in the natural gas system during the restoration process of the integrated electricity-gas energy system, and realize the multi-energy collaborative restoration of the integrated electricity-gas energy system. Description of the Drawings

[0084] Figure 1 is a schematic flow chart of a power supply restoration decision optimization method for an integrated electricity-gas energy system provided by an embodiment of the present invention;

[0085] Figure 2 is a schematic structural diagram of a power supply restoration decision optimization device for an integrated electricity-gas energy system provided by an embodiment of the present invention;

[0086] Figure 3 This is the internal structure diagram of the computer device provided by the embodiment of the present invention. Specific implementation manners

[0087] The technical solution of the present invention will be described in detail below through the accompanying drawings and specific embodiments. The same reference numerals in the drawings denote the same or similar components or parts. Those skilled in the art should understand that these drawings are not necessarily drawn to scale. The embodiments of the present application and the specific features in the embodiments are detailed descriptions of the technical solution of the present application, rather than limitations on the technical solution of the present application. Without conflict, the technical features in the embodiments of the present application and the embodiments can be combined with each other.

[0088] The term "and / or" in this article is merely a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this article generally represents an "or" relationship between the associated objects before and after.

[0089] Embodiment 1:

[0090] As Figure 1 shown, the embodiment of the present invention provides a method for optimizing the decision-making of the energy supply restoration of an electric-gas integrated energy system. Figure 1 This is the flow chart of the method for optimizing the decision-making of the energy supply restoration of the electric-gas integrated energy system. This flow chart only shows the logical sequence of the method described in this embodiment. On the premise of not conflicting with each other, in other possible embodiments of the present invention, the steps shown or described can be completed in a different Figure 1 sequence from that shown.

[0091] The method for optimizing the decision-making of the energy supply restoration of the electric-gas integrated energy system provided in this embodiment can be applied to a terminal and can be executed by a device for optimizing the decision-making of the energy supply restoration of the electric-gas integrated energy system. This device can be implemented in a software and / or hardware manner and can be integrated in the terminal.

[0092] See Figure 1 , the method of the embodiment of the present invention specifically includes the following steps:

[0093] Step 1: Based on the comprehensive demand response of the loads in the electric-gas integrated energy system, with the goal of maximizing the net restoration benefit during the system's energy supply restoration process, construct an objective function for the decision-making of the energy supply restoration of the electric-gas integrated energy system.

[0094] The demand response of a single - energy system usually manifests as the flexible regulation ability of the load for the reduction and transfer of the energy demand of this energy, corresponding to the curtailable load and the shiftable load respectively. The demand response presents spatio - temporal coupling characteristics under the condition of limited total energy supply. The same end - user energy demand can be satisfied by different energy systems through redundant energy - using devices. For example, the user's heat energy demand can be independently obtained from the power supply or gas supply system by an induction cooker or a gas stove, which provides conditions for the load to participate in the demand response of other energy systems. The present invention proposes integrated demand response (IDR) to describe the active response behavior of the load in the electric - gas integrated energy system under the action of incentives or compensations, and classifies it as:

[0095] Curtailable load, which is an energy - using load that can interrupt the end - user energy demand during a certain period;

[0096] Shiftable load, which is an energy - using load that can transfer the end - user energy demand during a certain period to other periods of the same energy system;

[0097] Substitutable load, which is an energy - using load that can replace the end - user energy demand during a certain period by other energy systems through redundant energy - using devices.

[0098] Among them, the substitutable load in the integrated demand response and the gas - to - power (G2P) of the gas turbine and the power - to - gas (P2G) of the fuel cell both show cross - energy coupling of the electrical system. The electrical coupling of G2P and P2G shows the source - load conversion in different spaces between electrical systems, while the electrical coupling of the substitutable load shows the electrical demand switching of the load in the same space.

[0099] The energy consumption interrupted by the substitutable load is the substituted quantity, and the energy increased in supply by other energy systems is the substituted - in quantity. There is a conversion relationship between the substituted quantity and the substituted - in quantity, and the conversion relationship depends on the energy - consumption efficiency of the relevant redundant energy - using devices. The present invention uses a substitution coefficient to characterize the conversion relationship between the substituted quantity and the substituted - in quantity.

[0100] The calculation formula for the substitution coefficient between the substituted quantity and the substituted - in quantity is:

[0101]

[0102] Where, is the substitution coefficient of converting electrical energy to gas energy at node g in time step t; is the substitution coefficient of converting gas energy to electrical energy at node i in time step t; is the electro - thermal efficiency at node i in time step t; is the gas - thermal efficiency at node g in time step t; ρ is the density of natural gas, W Gis the calorific value of natural gas.

[0103] In the integrated electricity-gas energy system, the amount of terminal energy demand of the power system load replaced by the natural gas system is the power load to gas load (PL2GL), and the amount of terminal energy demand of the natural gas system load replaced by the power system is the gas load to power load (GL2PL).

[0104] The objective function of the energy supply restoration decision for the integrated electricity-gas energy system is:

[0105] max(F - C int - C shift - C replace )(2)

[0106] where F is the restoration revenue of the integrated electricity-gas energy system; C int is the compensation cost for the integrated electricity-gas energy system to implement curtailment for the load participating in the integrated demand response, C shift is the compensation cost for the integrated electricity-gas energy system to implement transfer for the load participating in the integrated demand response, C replace is the compensation cost for the integrated electricity-gas energy system to implement substitution for the load participating in the integrated demand response;

[0107] The calculation formulas for the above-mentioned F, C int , C shift and C replace are respectively:

[0108]

[0109]

[0110] where is the set of power load nodes in the distribution network; is the set of load nodes in the gas distribution network; Δt is the time step length of observation; T is the total number of observation time steps, and the total number of observation time steps is the ratio of the recovery time required by the system with the longer recovery time in the power system and the natural gas system in the integrated electricity-gas energy system to the time step length of observation; is the weight of load node i at time step t; is whether the power supply of load node i is restored at time step t, with a value of 1 indicating power supply restoration and a value of 0 indicating non-restoration of power supply; is the electricity to be restored for load node i at time step t after the load participates in the integrated demand response; is the curtailed electricity in the load of load node i at time step t, is the transferred electricity in the load of load node i at time step t, The electricity volume transferred out from the load at node i at time step t. The electricity volume replaced by gas in the load at node i at time step t. The electrical load replacement amount of the gas load at node i at time step t; μ E The electricity price. The unit compensation price for the reduced amount of electrical load. The unit compensation price for the transferred-out amount of electrical load. The unit compensation price for the replaced amount of electrical load. The weight of the gas load node i at time step t. Whether the gas supply of the gas load at node g at time step t is restored. The value is 1 for restored gas supply and 0 for non-restored gas supply. The volume of natural gas to be restored at node i after the load participates in the integrated demand response at time step t. The volume of the reduced gas load at node g at time step t. The volume of the transferred-in gas load at node g at time step t. The volume of the transferred-out gas load at node g at time step t. The volume of the gas load replaced by electricity at node g at time step t. The gas load replacement amount of the electrical load at node g at time step t; μ G The gas price. The unit compensation price for the reduced amount of gas load. The unit compensation price for the transferred-out amount of gas load. The unit compensation price for the replaced amount of gas load.

[0111] Step 2: Establish the integrated demand response constraints, gas turbine gas-electricity conversion constraints, distribution network constraints, and gas distribution network constraints for the energy supply restoration decision-making objective function of the electricity-gas integrated energy system.

[0112] Considering that the nodes where the loads are located in the electricity-gas integrated energy system during the restoration process may be in an out-of-service state waiting to be restored. Only the nodes in the operating state can transfer in and out loads, reduce loads, or replace loads with other energy forms. The replaced amount is independent of the load operating state. Therefore, the integrated demand response constraints of the present invention consist of electrical load demand response constraints and gas load demand response constraints.

[0113] The electrical load demand response constraints include:

[0114]

[0115] Among them, H is theoretically an infinitely large positive number. In actual engineering, it can take values such as 1000 or 10000, etc.; P i,t The planned demand power at node i at time step t. The proportion of transferable electrical load contracted at time step \(t\) and node \(i\) to the planned demand power The proportion of curtailable electrical load contracted at time step \(t\) and node \(i\) to the planned demand power The proportion of substitutable electrical load contracted at time step \(t\) and node \(i\) to the planned demand power The amount of curtailed curtailable electrical load at node \(i\) at time step \(t\) The amount of substituted substitutable electrical load at node \(i\) at time step \(t\) The amount of substituted substitutable gas load at node \(g\) at time step \(t\) The amount of transferred transferable electrical load at node \(i\) at time step \(t\) When it is greater than 0, it represents the amount of transferred out; When it is less than 0, it represents the amount of transferred in; The electrical load substitution amount of the gas load at node \(i\) at time step \(t\) The power demand of node \(i\) at time step \(t\) after the load participates in the integrated demand response The electrical load transfer in and out flag bit, with a value of 1 indicating transferring out the electrical load and a value of 0 indicating transferring in the electrical load; Etype = {shift, int, replace, GL2PL}

[0116] Under the condition of limited total energy supply, the integrated demand response presents the characteristics of multi - energy spatio - temporal coupling. The coupling degree is restricted by the shortage degree of the total energy supply, redundant energy - using equipment and user willingness. During the restoration process of the electricity - gas integrated energy system, the operating conditions are complex and changeable, and the coupling characteristics of the integrated demand response will also be affected by the restoration state of the load nodes. The transferable electrical load is divided into two situations: transferring in and transferring out, and it can only be transferred in when the load is restored, as shown in Equation (7); the curtailable electrical load can only be curtailed when the load is restored, as shown in Equation (8); the amount of substituted substitutable electrical load needs to meet Equation (9); the transferred - out electrical load during the restoration period should be equal to the transferred - in electrical load, as shown in Equation (10), and the gas load can only be substituted by the electrical load at the current time step, as shown in Equation (11); the gas load cannot be substituted when the electrical load node is not restored, as shown in Equation (12); Equations (11), (12) and (22) jointly constitute the constraints for the substitutable electrical load to participate in the integrated demand response; after participating in the integrated demand response, the electrical load demand of the node is shown in Equation (13); the calculation of the transferred - out and transferred - in electrical load of the node is shown in Equations (14) to (18); the unit conversion relationship is shown in Equation (19).

[0117] Similar to the above - mentioned electrical load demand response constraints, the gas load demand response constraints include:

[0118]

[0119]

[0120] Among them, Mg,t The planned demand flow of node g at time step t; The proportion of the transferable gas load contracted at node g at time step t to the planned demand power, The proportion of the curtailable gas load contracted at node g at time step t to the planned demand power, The proportion of the substitutable gas load contracted at node g at time step t to the planned demand power; The curtailed amount of the curtailable gas load of node g at time step t; The transferred amount of the transferable gas load of node g at time step t, When it is greater than 0, it represents the transferred-out amount, When it is less than 0, it represents the transferred-in amount; The gas load substitution amount of the electrical load of node g at time step t; The flow demand of node g at time step t after being adjusted by integrated demand response; The gas load transfer-in and transfer-out flag bit, with a value of 1 indicating the transfer-out of gas load and a value of 0 indicating the transfer-in of gas load; Gtype = {shift, int, replace, PL2GL}.

[0121] All gas turbines in the present invention have self-starting capabilities, and the gas-electric conversion constraints of the gas turbines are:

[0122]

[0123] Among them, is the set of nodes in the distribution network where gas turbines are configured; is the set of gas distribution network nodes connected to the intake ports of gas turbines, is the active power output by the gas turbine of node i at time step t; k i is the energy conversion parameter output by the gas turbine of node i at time step t; is the start-stop state of the gas turbine; is the upper limit of the gas intake flow of the gas turbine configured at node g, is the lower limit of the gas intake flow of the gas turbine configured at node g.

[0124] In view of the difference in the energy transmission rates between the power system and the natural gas system in the electric-gas integrated energy system, the present invention uses a steady-state model to model the power system and a transient model to model the natural gas system. And based on the constructed power system model, the distribution network constraints of the power supply restoration decision objective function of the electric-gas integrated energy system are established, and based on the constructed natural gas system model, the gas distribution network constraints of the power supply restoration decision objective function of the electric-gas integrated energy system are established.

[0125] When the power supply of the distribution network in the integrated electrical and gas energy system is restored, it usually starts from the energized area or a power source with self-starting ability and gradually restores power outward, and finally forms one or more energized areas that can operate independently. In order to describe the constraint conditions that the restoration state variables of the nodes and branches in the energized area of the distribution network need to satisfy, the present invention constructs a division model of the energized area in the distribution network and a topological structure model of the distribution network.

[0126] The division model of the energized area is as follows:

[0127]

[0128]

[0129] Among them, is the set of energized areas; is the set of nodes in the distribution network; is the set of branches in the distribution network; is the restoration state of node i at time step t in energized area m, is the restoration state of the load carried by node i at time step t in energized area m, is the restoration state of branch ij at time step t in energized area m; and both take a value of 1 indicating restored and 0 indicating not restored.

[0130] Equation (35) means that a node can belong to at most one energized area at any time step; Equation (36) means that the nodes in the energized area need to maintain the restored state; Equation (37) means that the necessary condition for load restoration is the restoration of its connected node; Equation (38) means that the restored load in the energized area needs to maintain the restored state; Equations (39) to (41) mean that if branch ij belongs to a certain energized area, its two end nodes i and j also belong to the same energized area; Equation (42) means that the branches in the energized area need to maintain the restored state; Equation (43) means that at most one branch can be newly added to the energized area in one observation time step.

[0131] Suppose in the distribution network, the node set Among them, is the set of nodes configured with power supplies; is the set of nodes configured with power supplies with self-starting ability; is the set of nodes configured with power supplies without self-starting ability.

[0132] The topological structure model of the distribution network is as follows:

[0133]

[0134] In the formula, is the restoration state of branch ij at time step t, taking a value of 1 indicating that the branch is restored and 0 indicating not restored; The node restoration status for configuring the power supply at time step t; The set of injection branches for node i; The set of outflow branches for node i; H is a positive infinity. The virtual output of the power supply with self-starting ability, The value of is a positive integer; The virtual power flow of the injection branch for node i, The value of is an integer; The virtual power flow of the outflow branch for node i, The value of is an integer.

[0135] Equation (44) constrains the radial topology of the energized area in the distribution network; Equation (45) is the virtual output of the restored power supply with self-starting ability; Equations (45) to (46) represent setting a virtual demand of 1 unit for the restored nodes. Therefore, in this patent, the node restoration status is used to represent the node virtual demand; Equation (47) is the virtual power flow of the restored branch; Equations (48) to (49) are the consistency constraints for the restoration status of the nodes and branches in the energized area.

[0136] The distribution network constraints include one or more of the power supply with self-starting ability constraint, power supply without self-starting ability constraint, power flow constraint, load power supply status constraint, transient frequency constraint, and branch restoration time constraint.

[0137] The power supply with self-starting ability constraint includes:

[0138]

[0139] Among them, P i B,max The upper limit of the active power output by the power supply with self-starting ability configured for node i; P i B,min The lower limit of the active power output by the power supply with self-starting ability configured for node i; The upper limit of the reactive power output by the power supply with self-starting ability configured for node i; The lower limit of the active power output by the power supply with self-starting ability configured for node i; The active power output by the power supply with self-starting ability configured for node i at time step t; The reactive power output by the power supply with self-starting ability configured for node i at time step t; ΔP i B,down and ΔP i B,up are the ramp constraints of the power supply with self-starting ability configured for node i.

[0140] Equations (50) to (51) provide the output constraints of the power supply with self-starting ability; Equation (52) is the ramp constraint of the power supply with self-starting ability.

[0141] Only after meeting the start-up conditions can the power supply without self-starting ability be restored. The constraints of the power supply without self-starting ability include:

[0142]

[0143] Among them, The restoration status of the power supply without self-starting ability configured for node i at time step t in the energized area m; The restoration status of the power supply without self-starting ability configured for node i at time step t in the distribution network; and Both take values of 1 indicating the restoration of the power supply without self-starting ability and 0 indicating the non-restoration of the power supply without self-starting ability; P i NB,max The upper limit of the active power output by the power supply without self-starting ability configured for node i; P i NB,min The lower limit of the active power output by the power supply without self-starting ability configured for node i; The upper limit of the reactive power output by the power supply without self-starting ability configured for node i; The lower limit of the reactive power output by the power supply without self-starting ability configured for node i; ΔP i NB,down and ΔP i NB,up Are the ramp constraints of the power supply without self-starting ability configured for node i.

[0144] Equation (53) states that the necessary condition for the restoration of the power supply without self-starting ability is the restoration of its connected node; Equation (54) is the consistency constraint of the restoration status of the power supply without self-starting ability; Equations (55) to (56) provide the output constraints of the power supply without self-starting ability; Equation (57) is the ramp constraint of the power supply without self-starting ability.

[0145] The present invention uses the Distflow power flow calculation to restore the power flow distribution in the distribution network during the restoration process. The relaxed Distflow power flow constraints include:

[0146]

[0147]

[0148] Among them, P ij,t Is the active power of branch ij at time step t; Q ij,t Is the active power of branch ij at time step t; Is the active power obtained by the object to be restored at node i at time step t; The active power obtained for the object to be restored at node i at time step t; The active power injected into node i at time step t; The reactive power injected into node i at time step t; r ij The resistance of branch ij x ij The reactance of branch ij; l ij,t The square of the current in branch ij at time step t; U i,t The square of the voltage at node i at time step t; The maximum apparent power that can pass through branch ij; The square of the maximum voltage of node i; The square of the minimum voltage of node i; The square of the maximum current that can pass through branch ij; The starting power required for the non-self-starting power source at node i at time step t; σ i,t The reactive power demand factor of node i at time step t.

[0149] Equations (58) and (59) are the active and reactive power balance constraints of the node; Equations (60) to (63) are the voltage-current relationship constraints of the restored branch ij; Equation (64) is the apparent power constraint of the branch; Equations (65) and (66) are the node voltage and branch current constraints; Equation (67) is the active power constraint flowing out of the node; Equation (68) is the reactive power constraint flowing out of the node.

[0150] The load power supply state constraint is:

[0151] The load restoration state of node i in the live zone m is consistent with its restoration state in the distribution network, and it needs to satisfy Equation (69):

[0152]

[0153] The transient frequency constraint is:

[0154] To avoid the system transient frequency exceeding the limit caused by load switching, the constraint on the single load switching amount of the present invention is shown in Equation (70):

[0155]

[0156] Among them, ξ is the proportion of the allowed single-time input or interrupted load.

[0157] The branch restoration time constraint is:

[0158] Let the observation time step required for branch restoration be Then the sum of the observation time steps required for branch restoration in the live zone i needs to be less than or equal to the current observation time step, as shown in Equation (71):

[0159]

[0160] The gas distribution network constraints include dynamic power flow constraints and / or gas source output constraints.

[0161] Considering that compressors are usually not configured in the gas distribution network, the gas distribution network in the integrated electricity-gas energy system of the present invention mainly consists of natural gas pipelines. The dynamic power flow constraints include: air pressure and gas flow constraints in the natural gas pipeline, node flow balance constraints of the natural gas pipeline, and node air pressure constraints of the natural gas pipeline.

[0162] Assume that parameters such as pressure and flow velocity are evenly distributed across the cross-section of the natural gas pipeline, the temperature change along the pipeline is small, and at the same time, the convection term and gravity term in the dynamic equation are ignored. A mathematical model of isothermal flow of natural gas along the pipeline is established, as shown in Equations (72) to (74):

[0163]

[0164] p = c 2 ρ (74)

[0165] Among them, p is the pipeline pressure; λ is the pipeline friction coefficient; ρ is the density of natural gas; A is the cross-sectional area of the pipeline; c is the speed of sound of the gas;

[0166] The partial differential equations shown in Equations (72) to (74) are converted into a system of linear equations using the Wendroff difference format to obtain the air pressure and gas flow constraints in the natural gas pipeline, as shown in Equations (75) to (77):

[0167]

[0168] Among them, is the set of pipelines in the gas distribution network; is the set of nodes in the gas distribution network; A gh is the cross-sectional area of pipeline gh; L gh is the pipeline length; is the average flow velocity of natural gas in pipeline gh; D gh is the inner diameter of pipeline gh; ρ g,t is the density of natural gas at node g at time step t; M g,t is the gas pressure at node g at time step t; p g,t is the mass flow rate of natural gas at node g at time step t;

[0169] At the pipeline node, the flow balance needs to be satisfied. Assume that the cross-sectional areas of all natural gas pipelines in the gas distribution network are equal. The node flow balance constraints of the natural gas pipeline are shown in Equations (78) and (79):

[0170]

[0171] Among them, is the injection flow rate of node g at time step t; is the gas acquisition flow rate of the object to be restored at node g at time step t; is the gas acquisition flow rate of the gas turbine configured for node g;

[0172] The node air pressure constraint of the natural gas pipeline is shown in Equation (80):

[0173]

[0174] The gas source output constraint describes the constraints that the gas flow rate obtained by the gas distribution network from the upper-level gas network and the pressure at the gas acquisition node should satisfy.

[0175] The gas source output constraint is shown in Equations (81) and (82):

[0176]

[0177]

[0178] Among them, is the set of nodes where the gas distribution network obtains gas from the upper-level gas network; is the gas acquisition flow rate of node g at time step t; is the maximum value of the gas acquisition flow rate of node g; is the minimum value of the gas acquisition flow rate of node g; is the set value of the outlet pressure of node g.

[0179] Step 3: Optimize and solve the power supply restoration decision objective function of the electric-gas integrated energy system with the comprehensive demand response constraint, gas turbine gas-electric conversion constraint, power distribution network constraint, and gas distribution network constraint, and determine the power supply restoration decision plan for the electric-gas integrated energy system.

[0180] The power supply restoration decision objective function of the electric-gas integrated energy system and the power supply restoration decision model composed of its various constraint conditions (comprehensive demand response constraint, gas turbine gas-electric conversion constraint, power distribution network constraint, and gas distribution network constraint) are as follows:

[0181]

[0182] Use the big M method to process the non-linear terms of the multiplication of 0-1 variables and continuous variables in the decision model, and at the same time use two square constraint equations with a 45-degree angle to approximate the capacity limit constraint equation (64) of the branch. Then the above decision model is converted into a mixed integer second-order cone model, and commercial solvers such as Gurobi can be used for solving.

[0183] Example 2:

[0184] Based on the same inventive concept as in Embodiment 1, an embodiment of the present invention further provides an electrical-gas integrated energy system power supply restoration decision optimization device for implementing the above-mentioned electrical-gas integrated energy system power supply restoration decision optimization method. The solution provided by this device for solving problems is similar to the solution described in the above method. Therefore, the specific limitations in the embodiment of the electrical-gas integrated energy system power supply restoration decision optimization device provided below can refer to the limitations on the electrical-gas integrated energy system power supply restoration decision optimization method in the above text, and will not be elaborated here.

[0185] As Figure 2 shown, an embodiment of the present invention provides an electrical-gas integrated energy system power supply restoration decision optimization device, including:

[0186] A power supply restoration decision objective function construction module, configured to construct an electrical-gas integrated energy system power supply restoration decision objective function based on the comprehensive demand response of the load in the electrical-gas integrated energy system, with the goal of maximizing the net restoration benefit during the system's power supply restoration process;

[0187] A constraint condition establishment module, configured to establish the comprehensive demand response constraint, gas-electric conversion constraint of the gas turbine, distribution network constraint, and gas distribution network constraint of the electrical-gas integrated energy system power supply restoration decision objective function;

[0188] A power supply restoration decision plan determination module, configured to perform optimization solution on the electrical-gas integrated energy system power supply restoration decision objective function with the comprehensive demand response constraint, gas-electric conversion constraint of the gas turbine, distribution network constraint, and gas distribution network constraint, and determine the electrical-gas integrated energy system power supply restoration decision plan.

[0189] Embodiment 3:

[0190] An embodiment of the present invention further provides a computer device, which can be a server, and its internal structure diagram can be as Figure 3As shown in the figure. The computer device includes a processor, a memory, an input / output interface (Input / Output, abbreviated as I / O), and a communication interface. Among them, the processor, the memory, and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program, and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and external devices. The communication interface of the computer device is used to communicate with external terminals through a network connection. When the computer program is executed by the processor, it realizes the power supply recovery decision optimization method of the electro-gas integrated energy system in the foregoing embodiments.

[0191] Those skilled in the art can understand that Figure 3 the structure shown in the figure is only a block diagram of some structures related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine some components, or have different component arrangements.

[0192] Embodiment 4:

[0193] The embodiment of the present invention also provides a computer-readable storage medium, on which a computer program is stored. When the program is executed by a processor, it realizes the steps of the following method:

[0194] Based on the comprehensive demand response of the load in the electro-gas integrated energy system, with the goal of maximizing the net recovery benefit during the system's energy supply recovery process, construct an electro-gas integrated energy system energy supply recovery decision objective function;

[0195] Establish the comprehensive demand response constraint, gas turbine gas-electric conversion constraint, distribution network constraint, and gas distribution network constraint of the electro-gas integrated energy system energy supply recovery decision objective function;

[0196] Optimize and solve the electro-gas integrated energy system energy supply recovery decision objective function with the comprehensive demand response constraint, gas turbine gas-electric conversion constraint, distribution network constraint, and gas distribution network constraint to determine the electro-gas integrated energy system energy supply recovery decision plan.

[0197] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0198] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowchart and / or block diagram, as well as the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate means for implementing the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0199] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing devices to work in a specific manner, so that the instructions stored in the computer-readable memory generate a manufactured article including instruction means, and the instruction means implement the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0200] These computer program instructions can also be loaded onto a computer or other programmable data processing devices, so that a series of operation steps are executed on the computer or other programmable devices to generate a computer-implemented process. Thus, the instructions executed on the computer or other programmable devices provide steps for implementing the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0201] The embodiments of the present invention have been described above in conjunction with the accompanying drawings. However, the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make many forms without departing from the spirit and scope of the present invention as protected by the claims. All of these are within the protection scope of the present invention.

Claims

1. A method for optimizing energy supply recovery decision of an electric-gas integrated energy system, characterized in that: include: Based on the comprehensive demand response of loads in the electricity-gas integrated energy system, the objective function of energy supply restoration decision-making of the electricity-gas integrated energy system is constructed with the goal of maximizing the net recovery benefit during the system energy restoration process. Establishing the comprehensive demand response constraints, gas turbine gas-to-electricity conversion constraints, distribution network constraints and gas distribution network constraints of the energy supply recovery decision objective function of the electricity-gas integrated energy system; The energy supply recovery decision objective function of the electricity-gas integrated energy system with the comprehensive demand response constraints, gas turbine gas-to-electricity conversion constraints, distribution network constraints and gas distribution network constraints is optimized and solved to determine the energy supply recovery decision plan of the electricity-gas integrated energy system.

2. The method for optimizing energy supply recovery decision of an electric-gas integrated energy system according to claim 1 is characterized in that: The comprehensive demand response of the load in the electricity-gas integrated energy system is: the active response behavior of the load in the electricity-gas integrated energy system under the action of incentives or compensation, including: Load reduction means the energy load that can interrupt the terminal energy demand during a certain period of time; Transferable loads are loads that can transfer the terminal energy demand in a certain period to the energy demand in other periods of the same energy system; Replaceable load refers to the energy load that can replace the terminal energy demand in a certain period of time with energy supply from other energy systems through redundant energy equipment; The energy consumption of the replaceable load interruption is the replaced amount, and the energy supplied by other energy systems is the replaced amount. The calculation formula of the replacement coefficient between the replaced amount and the replaced amount is: in, is the conversion coefficient of electrical energy into gas energy at node g at time step t; is the conversion coefficient of gas energy into electric energy at node i at time step t; is the electrothermal efficiency of node i at time step; is the gas thermal efficiency at the time step node g; ρ is the density of natural gas, W G is the calorific value of natural gas; In the electricity-gas integrated energy system, the amount of terminal energy demand of the power system load that is replaced by the natural gas system is the gas load replacement amount of the electric load, and the amount of terminal energy demand of the natural gas system load that is replaced by the power system is the electric load replacement amount of the gas load.

3. The method for optimizing energy supply recovery decision of an electric-gas integrated energy system according to claim 2 is characterized in that: The energy supply recovery decision objective function of the electricity-gas integrated energy system is: max(F-C int -C shift -C replace ) Where F is the recovery benefit of the electricity-gas integrated energy system; C int The compensation cost for the electricity-gas integrated energy system to implement load reduction for participating in integrated demand response, C shift The compensation cost for the electricity-gas integrated energy system to transfer the load to participate in the integrated demand response, C replace Compensation costs for implementing alternatives for the electric-gas integrated energy system to participate in integrated demand response for loads; The F, C int , C shift and C replace The calculation formulas are: in, is the set of electrical load nodes in the distribution network; is the set of load nodes in the gas distribution network; Δt is the observation time step length; T is the total number of observation time steps, which is the ratio of the required recovery time of the power system and the natural gas system in the electric-gas integrated energy system that require longer recovery time to the observation time step length; is the weight of load node i at time step t; Whether the power supply of the electric load of node i is restored at time step t, the value is 1 for restoration of power supply, and the value is 0 for non-restoration of power supply; is the amount of electricity to be restored at node i at time step t after the load participates in the comprehensive demand response; is the amount of power that has been cut in the load of node i at time step t, is the amount of electricity transferred into the load of node i at time step t, is the amount of electricity transferred out of the load at node i at time step t, is the amount of electricity in the load of node i at time step t that has been replaced by gas; is the replacement of the gas load of node i by the electric load at time step t; μ E For electricity prices; is the unit compensation price for the amount of electricity load reduction, is the unit compensation price for the transferred electricity load. The unit compensation price for the amount of electricity load replaced; is the weight of the step load node i at time t; Whether the gas load of node g at time step t has been restored to supply gas, a value of 1 indicates that the gas supply has been restored, and a value of 0 indicates that the gas supply has not been restored; is the volume of natural gas to be restored at node i at time step t after the load participates in the comprehensive demand response; is the reduced gas load volume of node g at time step t, is the gas load volume transferred to node g at time step t, is the gas load volume transferred out of node g at time step t, is the gas load volume of node g that has been replaced by electricity at time step t; is the gas load replacement of the electric load of node g at time step t; μ G For gas price; is the unit compensation price for the amount of gas load reduction, is the unit compensation price for the transferred gas load. It is the unit compensation price for the amount of gas load replaced.

4. The method for optimizing energy supply recovery decision of an electric-gas integrated energy system according to claim 3 is characterized in that: The comprehensive demand response constraint includes an electric load demand response constraint and a gas load demand response constraint; The electric load demand response constraints include: Among them, H is an infinite positive number; P i,t is the planned required power of node i at time step t; is the proportion of the transferable load contracted by node i at time step t to the planned power demand, is the proportion of the reduced electric load contracted by node i at time step t to the planned power demand, The proportion of the alternative electric load contracted by node i at time step t to the planned power demand; is the amount of load reduction that can be achieved at node i at time step t; is the replaced amount of replaceable electric load of node i at time step t; is the replaced amount of replaceable gas load at node g at time step t; is the transferred amount of transferable load of node i at time step t, When it is greater than 0, it indicates the amount has been transferred out. When it is less than 0, it means the amount has been transferred in; is the replacement of the gas load of node i by the electric load at time step t; is the power demand of node i at time step t after the load participates in the integrated demand response; It is the flag bit for transferring in and out of electric load. The value of 1 indicates transferring out of electric load, and the value of 0 indicates transferring in of electric load. Etype = {shift, int, replace, GL2PL}; The gas load demand response constraints include: Among them, M g,t is the planned demand flow of node g at time step t; is the proportion of the transferable gas load contracted by node g at time step t to the planned power demand, is the ratio of the contracted gas load that can be reduced at node g in time step t to the planned power demand, The proportion of the alternative gas load contracted for node g at time step t to the planned power demand; is the amount of gas load reduction that can be achieved at node g at time step t; is the transfer amount of transferable gas load at node g at time step t, When it is greater than 0, it indicates the amount has been transferred out. When it is less than 0, it means the amount has been transferred in; is the gas load replacement of the electric load of node g at time step t; is the flow demand of node g at time step t after adjustment through comprehensive demand response; It is the gas load transfer-in and transfer-out flag. The value of 1 indicates transfer-out gas load, and the value of 0 indicates transfer-in gas load. Gtype = {shift, int, replace, PL2GL}.

5. The method for optimizing energy supply recovery decision of an electric-gas integrated energy system according to claim 3 is characterized in that: The gas turbine gas-to-electricity conversion constraint is: in, A set of nodes configured with gas turbines in a distribution network; is the set of gas distribution network nodes connected to the gas turbine air inlet, is the active power output of the gas turbine at node i at time step t; k i is the energy conversion parameter of the gas turbine output at node i at time step t; The start and stop status of the gas turbine; The upper limit of the gas flow rate of the gas turbine configured for node g, The lower limit of the gas flow rate of the gas turbine configured for node g.

6. The method for optimizing energy supply recovery decision of an electric-gas integrated energy system according to claim 3 is characterized in that: When the power distribution network in the electric-gas integrated energy system is restored, the powered domain or the power source with self-starting capability is used as the starting point to gradually restore power to the outside, and eventually one or more powered domains capable of independent operation are formed; The charged domain partition model is: in, is a collection of charged domains; is a set of distribution network nodes; It is a collection of distribution network branches; is the restored state of node i at time step t in the charged domain m, is the recovery state of the load carried by node i in the charged domain m at time step t, is the recovery state of branch ij at time t in charged domain m; and The value is 1 for restored, and 0 for unrestored. Assume that in the distribution network, the node set in, A collection of nodes for configuring power supplies; A collection of nodes configured with a power supply having self-start capability; A collection of nodes that are configured with power supplies without self-start capability; The topological structure model of the distribution network in the electricity-gas integrated energy system is: In the formula, is the recovery state of branch ij at time step t, with a value of 1 indicating that the branch is recovered and 0 indicating that it is not recovered; The node with power configured for time step t is restored to state; is the set of injection branches of node i; is the outflow branch set of node i; H is an infinite positive number; It is the virtual output of the power supply with self-starting capability. The value of is a positive integer; The virtual power flow injected into the branch for node i, The value of is an integer; is the virtual power flow of the outflow branch of node i, The value of is an integer.

7. The method for optimizing energy supply recovery decision of an electric-gas integrated energy system according to claim 6 is characterized in that: The distribution network constraints include one or more of power supply constraints with self-starting capability, power supply constraints without self-starting capability, power flow constraints, load power supply status constraints, transient frequency constraints, and branch recovery time constraints.

8. The method for optimizing energy supply recovery decision of an electric-gas integrated energy system according to claim 7 is characterized in that: The power supply constraints with self-start capability include: Among them, P i B,max The upper limit of active power output of the power supply with self-starting capability configured for node i; P i B,min The lower limit of the active power output of the power supply with self-starting capability configured for node i; Q i B,max The reactive power upper limit of the power supply with self-starting capability configured for node i; Q i B,min The lower limit of the active power output of the power supply with self-start capability configured for node i; The active power output at time step t of the power source with self-starting capability configured for node i; The reactive power output of the power supply with self-starting capability configured for node i at time step t; ΔP i B,down and ΔP i B,up The ramp constraint of the power supply with self-starting capability configured for node i; The power supply constraints without self-starting capability include: in, The recovery state of the power supply without self-starting capability configured for node i in the powered domain m at time step t; The recovery state of the power supply without self-starting capability configured for node i in the distribution network at time step t; and The value of 1 indicates that the power supply has been restored without self-start capability, and the value of 0 indicates that the power supply has not been restored without self-start capability; P i NB,max The upper limit of active power output of the power supply without self-starting capability configured for node i; P i NB,min The lower limit of the active power output of the power supply without self-starting capability configured for node i; Q i NB,max The reactive power upper limit of the power supply without self-starting capability configured for node i; Q i NB,min The lower limit of reactive power output of the power supply without self-starting capability configured for node i; ΔP i NB,down and ΔP i NB,up The ramp constraint of the power supply without self-starting capability configured for node i; The power flow constraints include: Among them, P ij,t is the active power of branch ij at time step t; Q ij,t is the active power of branch ij at time step t; is the active power obtained by the object to be restored at node i at time step t; is the active power obtained by the object to be restored at node i at time step t; is the active power injected into node i at time step t; is the reactive power injected into node i at time step t; r ij is the resistance x of branch ij ij is the reactance of branch ij; l ij,t is the square of the current in branch ij at time t; U i,t is the square of the voltage at node i at time step t; is the maximum apparent power that can pass through branch ij; is the square of the maximum voltage at node i; is the square of the minimum voltage at node i; is the square of the maximum current that can pass through branch ij; is the starting power required by the power supply without self-starting capability at node i at time step t; i,t is the reactive power demand factor of node i at time step t; The load power supply state constraint is: The transient frequency constraint is: Among them, ξ is the proportion of load that can be put into operation or interrupted at a single time; The branch restoration time constraint is: Assume that the observation time step required for branch recovery is Then the sum of the observation time steps required for branch recovery in the charged domain i needs to be less than or equal to the current observation time step:

9. The method for optimizing energy supply recovery decision of an electric-gas integrated energy system according to claim 3 is characterized in that: The gas distribution network constraints include dynamic flow constraints and / or gas source output constraints.

10. The method for optimizing energy supply recovery decision of an electric-gas integrated energy system according to claim 9, characterized in that: The gas distribution network in the electricity-gas integrated energy system is composed of natural gas pipelines, and the dynamic flow constraints include: gas pressure and gas flow constraints in the natural gas pipelines, node flow balance constraints of the natural gas pipelines, and node gas pressure constraints of the natural gas pipelines; The mathematical model of isothermal flow of natural gas along the pipeline is: p6c 2 ρ Where, p is the pipeline pressure; λ is the pipeline friction coefficient; ρ is the natural gas density; A is the pipeline cross-sectional area; c is the sound velocity of the gas; The mathematical model is converted into a linear equation system using the Wendroff difference format to obtain the gas pressure and gas flow constraints in the natural gas pipeline: in, It is a collection of pipelines for the gas distribution network; A is the node set of the gas distribution network; gh is the cross-sectional area of ​​the pipe gh; .L gh . is the length of the pipeline; is the average flow rate of natural gas in pipeline gh; D gh is the inner diameter of the pipe gh; ρ g,t is the natural gas density at node g at time step t; M g,t is the natural gas pressure at node g at time step t; p g,t is the natural gas mass flow rate at node g at time step t; Assuming that the cross-sectional areas of the natural gas pipelines are equal, the node flow balance constraint of the natural gas pipeline is: in, is the injection flow of node g at time step t; is the gas flow of the object to be restored at the node g at time step t; The gas flow rate of the gas turbine configured for node g; The node pressure constraint of the natural gas pipeline is: The gas source output constraints include: in, It is a set of nodes that the gas distribution network obtains gas from the upper gas network; is the gas flow rate of node g at time step t; Get the maximum value of airflow for node g; Get the minimum value of airflow for node g; Set the outlet pressure of node g.

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