Low-carbon economic dispatch method for integrated energy system considering variable operating characteristics of energy conversion equipment

Abstract

This invention relates to a low-carbon economic dispatch method for integrated energy systems that considers the variable operating conditions of energy conversion equipment, belonging to the field of power systems. The method includes the following steps: S1: Combining the variable operating conditions of energy conversion equipment in the integrated energy system with static energy hubs to construct a dynamic energy hub state transition model for the integrated energy system; S2: Combining a full life-cycle analysis method with a carbon quota trading mechanism to construct a carbon trading model for the integrated energy system; S3: Based on the dynamic energy hub state transition model and the carbon trading model, constructing a low-carbon economic dispatch model for the integrated energy system that considers the variable operating conditions of energy conversion equipment, and solving for the low-carbon economic dispatch strategy that considers the variable operating conditions of energy conversion equipment. This method can provide technical support for the operation and dispatch of integrated energy systems, and has advantages such as low system operating costs, low carbon emissions, and flexible and reliable operation.

Description

Technical Field

[0001] This invention belongs to the field of power systems and relates to a low-carbon economic dispatch method for integrated energy systems that takes into account the variable operating conditions of energy conversion equipment. Background Technology

[0002] With the development of the social economy, the relationship between global energy utilization patterns and environmental protection has become increasingly severe, and carbon emissions have attracted much attention. Integrated energy systems (IES) have the technical advantages of realizing the coupling and coordinated control of heterogeneous energy consumption structures of multiple energy systems, and provide a feasible way to solve the high energy consumption, low efficiency and insufficient renewable energy absorption of the energy structure. Its optimized scheduling has become a research hotspot.

[0003] In an Energy System (IES), there are numerous heterogeneous energy sources that are closely coupled. As coupling nodes within these networks, the energy conversion equipment exhibits significant nonlinear characteristics in its operation due to varying actual conditions, particularly differences in load rates. Therefore, the accuracy of the variable operating condition characteristics of the IES model directly impacts the economic operation of the actual system. Against this backdrop, this paper analyzes the variable operating condition characteristics of the IES energy conversion equipment, obtains the state process of the IES energy hub under these conditions, and enables dynamic correction of the actual operating efficiency of the IES energy conversion equipment.

[0004] In the context of low-carbon power systems, it is necessary to rationally quantify the carbon emission coefficients in energy activities. By combining life cycle assessment (LCA) with a carbon quota trading mechanism, the carbon emission coefficients of energy-integrated systems (IES) are quantitatively analyzed, and an IES economic dispatch model aimed at optimizing the low-carbon economy is established. This effectively improves the rationality of IES dispatch schemes, reduces system operating costs and carbon emissions, and facilitates optimized IES dispatch and the realization of low-carbon pathways. Summary of the Invention

[0005] In view of this, the purpose of this invention is to provide a low-carbon economic dispatch method for a comprehensive energy system that takes into account the variable operating conditions of energy conversion equipment. Based on a static energy hub, a dynamic energy hub variable operating condition model is constructed by combining the variable operating conditions of IES energy conversion equipment, and the LCA energy chain analysis method is combined with the carbon quota trading mechanism.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A low-carbon economic dispatch method for a comprehensive energy system that takes into account the variable operating conditions of energy conversion equipment includes the following steps:

[0008] S1: Combine the variable operating condition characteristics of energy conversion equipment in the integrated energy system with the static energy hub to construct a dynamic energy hub state transition model for the integrated energy system.

[0009] S2: Combine the whole life cycle analysis method with the carbon quota trading mechanism to construct a comprehensive energy system carbon trading model;

[0010] S3: Based on the dynamic energy hub state transition model of the integrated energy system and the carbon trading model of the integrated energy system, construct a low-carbon economic dispatch model of the integrated energy system that takes into account the variable operating conditions of energy conversion equipment, and solve for the low-carbon economic dispatch strategy that takes into account the variable operating conditions of energy conversion equipment.

[0011] Furthermore, the energy conversion equipment in the integrated energy system includes a combined heat and power unit, a gas boiler, an absorption chiller, and an electric chiller. The combined heat and power unit consists of a gas turbine and a waste heat boiler. The multiple energy storage devices in the integrated energy system include a power storage unit and a thermal storage unit.

[0012] Furthermore, step S1, which involves constructing the dynamic energy hub state transition model for the integrated energy system, includes:

[0013] S11: Modeling the variable operating condition characteristics of energy conversion equipment in an integrated energy system, represented as:

[0014]

[0015]

[0016]

[0017]

[0018] In the formula: For CHP variable operating condition electrical efficiency. For the CHP variable operating condition thermoelectric ratio, η GB For GB variable operating condition efficiency, η AC For AC variable operating condition efficiency; These are the fitting coefficients for the CHP variable operating condition electrical efficiency. The fitting coefficients for the thermoelectric ratio under CHP variable operating conditions are: The fitting coefficients for GB variable operating condition efficiency are... Fitting coefficients for AC variable operating condition efficiency; p chp p represents the electrical load factor of CHP. gb For a load factor of GB, p ac The load factor of the AC;

[0019] S12: Based on the static energy hub model of the integrated energy system, establish the dynamic energy hub state transition model of the integrated energy system:

[0020]

[0021] In the formula: L e L g L h L c For load demand; Input power to the energy source; These are the power conversion efficiency and the heat-to-power ratio of the CHP unit, respectively; η GB η EC η AC The energy conversion efficiencies are GB, EC, and AC, respectively. These represent the input power of the energy conversion equipment CHP, GB, EC, and AC, respectively; ΔS e ΔS g ΔS h ΔS c These are the dispatch power of the energy storage device;

[0022]

[0023] In the formula: The system uses externally purchased energy; P PV P WT These represent the power output of photovoltaic power generation and wind power generation, respectively.

[0024] S13: The state transition model of the dynamic energy hub of the integrated energy system is simplified as follows:

[0025] L = P in +CP tr +S (7)

[0026] In the formula: L is the energy load vector; P in C is the energy injection vector; P is the energy coupling matrix; tr S is the energy coupling vector; S is the energy storage power vector.

[0027] Furthermore, the integrated energy system carbon trading model described in step S2 is as follows:

[0028]

[0029] In the formula: the positive or negative value of f2 represents the purchase and sale of carbon emission credits; the former represents the additional cost, and the latter represents the revenue gained. For unit carbon cost, K 1,i K represents the total carbon dioxide emissions of equipment i during actual operation. 2,iFor a given object i, the carbon emission allowance;

[0030] The carbon emission coefficient is quantified and characterized using formula (9):

[0031] K 1,i =K 1,pi +K 1,ti +K 1,gi (9)

[0032] In the formula: K 1,i K represents the total carbon emission coefficient of the energy chain for energy device i and its corresponding energy type; 1,pi K represents the total carbon emission coefficient of the corresponding energy type production process for energy equipment i; 1,ti K represents the total carbon emission coefficient of the energy storage stage for the corresponding energy type of energy equipment i; 1,gi This refers to the total carbon emissions from the use of energy equipment i for the corresponding energy type.

[0033] Further, step S3, based on the dynamic energy hub state transition model of the integrated energy system and the carbon trading model of the integrated energy system, constructs a low-carbon economic optimization scheduling model for the integrated energy system, and solves for a low-carbon economic scheduling strategy considering the variable operating characteristics of energy conversion equipment, including:

[0034] The integrated energy system low-carbon economic dispatch model, which takes into account the variable operating conditions of energy conversion equipment, aims to minimize the sum of the conventional operating costs, carbon emission costs, and variable operating condition correction costs of the integrated energy system.

[0035] min f=f1+f2+f3 (10)

[0036] In the formula: f is the total cost of IES; f1 is the conventional operating cost; f2 is the carbon emission cost; f3 is the cost of adjusting for different operating conditions;

[0037]

[0038] In the formula: C(t) is the unit energy purchase cost at time t, including the unit electricity purchase cost C. grid (t), Unit gas purchase cost C gas (t); P b (t) represents the energy purchased during time period t, including the purchased power P. buy (t), Gas purchasing power G buy (t); Δt is the duration of the scheduling period; N w The number of maintenance equipment; Unit equipment maintenance cost; P i (t) represents the operating power of device i during time period t;

[0039]

[0040] In the formula: L n The required response load for the IES is denoted by n, which includes four energy sources: electricity, gas, heat, and cooling, and L represents the time period t. n The unit correction cost includes the unit energy correction cost C. e (t), Unit additional carbon emission cost For time period t, due to L n The corrective power resulting from the difference between the scheduled power and the actual power.

[0041] Furthermore, the integrated energy system low-carbon economic dispatch model that takes into account the variable operating conditions of energy conversion equipment has the following constraints:

[0042] Constraints of energy storage devices:

[0043]

[0044] SOC min ≤SOC0≤SOC max (14)

[0045] SOC min ≤SOC t ≤SOC max (15)

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052] Where: SOC t The energy state at time t is the energy stored; δ ES The self-discharge rate of the energy storage device; SOC0, SOC max SOC min These are the initial, upper, and lower limits of the energy storage state, respectively. η represents the charging and discharging power of the energy storage device at time t, respectively; ES,s η ES,r These represent the charging and discharging efficiencies of energy storage devices, respectively; S es This refers to the rated capacity of the energy storage device. All are binary variables, when releasing energy When the value is 1, energy is stored. A value of 1 is used to limit the operating state of energy storage devices, P ES The rated power of the energy storage t represents the energy storage charging and discharging power during time period t; n represents the maximum number of charging and discharging cycles for the energy storage device per day.

[0053] Constraints of energy conversion equipment:

[0054] For the operating boundaries of all energy conversion devices in the system, the output constraints are as shown in equation (22):

[0055]

[0056] In the formula: P α,t The set representing the energy output of device α at time t includes CHP, GB, EC, and AC. and These represent the upper and lower limits of the energy output of device α, respectively.

[0057] Energy supply and demand balance constraints:

[0058] The matrix form of the energy hub variable operating condition model is expanded into the energy supply and demand balance constraint shown in equation (23):

[0059]

[0060] In the formula: L e,t L g,t L h,t L c,t These represent the electrical load, gas load, heat load, and cooling load at time t, respectively. Let t be the input power of the energy conversion device at time t.

[0061] The beneficial effects of this invention are as follows: The method analyzes the variable operating characteristics of IES energy conversion equipment, obtains the variable operating characteristic state process of the IES energy hub, and realizes dynamic correction of the actual operating efficiency of the IES energy conversion equipment. By combining the life cycle assessment (LCA) method with the carbon quota trading mechanism, the quantitative analysis of the IES carbon emission coefficient is achieved, and an IES economic scheduling model with the goal of optimizing the low-carbon economy is established. Finally, a case study analysis is conducted for typical day-ahead IES. The results show that considering the variable operating characteristics of energy conversion equipment and carbon emission costs improves the rationality of the scheduling scheme, reduces system operating costs and carbon emissions, and is conducive to the optimized scheduling of IES and the realization of low-carbon pathways.

[0062] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0063] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein:

[0064] Figure 1 This is a schematic diagram of the overall process of the present invention;

[0065] Figure 2 This is a busbar structure diagram of an integrated energy system;

[0066] Figure 3 The diagram shows the optimal power scheduling strategy.

[0067] Figure 4 The diagram shows the optimal thermal power scheduling strategy.

[0068] Figure 5 The diagram shows the optimal scheduling strategy for cooling power.

[0069] Figure 6 This is a status diagram of the energy storage device;

[0070] Figure 7 This is a status diagram of the thermal storage equipment. Detailed Implementation

[0071] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0072] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0073] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0074] This invention provides a low-carbon economic dispatch method for integrated energy systems that takes into account the variable operating conditions of energy conversion equipment, such as... Figure 1 As shown, the implementation process includes the following detailed steps:

[0075] Step 1: Combine the variable operating condition characteristics of the source conversion equipment in the integrated energy system with the static energy hub to construct a state transition model for the dynamic energy hub of the integrated energy system.

[0076] Modeling the variable operating condition characteristics of energy conversion equipment in an integrated energy system, the variable operating condition efficiency characteristics of energy conversion in the integrated energy system include the variable operating condition electrical efficiency of cogeneration units, the variable operating condition heat-to-power ratio of cogeneration units, the variable operating condition efficiency of gas boilers, and the variable operating condition efficiency of absorption chillers, which can be expressed as follows:

[0077]

[0078]

[0079]

[0080]

[0081] In the formula: For CHP variable operating condition electrical efficiency, For the CHP variable operating condition thermoelectric ratio, η GB For GB variable operating condition efficiency, η AC For AC variable operating condition efficiency; These are the fitting coefficients for CHP variable operating condition electrical efficiency, CHP variable operating condition thermoelectric ratio, GB variable operating condition efficiency, and AC variable operating condition efficiency, respectively; p chp p gb p ac These are the electrical load rates of CHP, GB, and AC, respectively.

[0082] Based on the static energy hub model of the integrated energy system, a dynamic energy hub state transition model of the integrated energy system is established:

[0083]

[0084] In the formula: L e L g L h L c For load demand; Input power to the energy source; These are the power conversion efficiency and the heat-to-power ratio of the CHP unit, respectively; η GB η EC η AC The energy conversion efficiencies are GB, EC, and AC, respectively. The input power of the energy conversion equipment (CHP, GB, EC, AC); ΔS e ΔS g ΔS h ΔS c This refers to the dispatch power of the energy storage device.

[0085]

[0086] In the formula: The system uses externally purchased energy; P PV P WT These represent the power output of photovoltaic power generation and wind power generation, respectively.

[0087] The above model can be simplified as follows:

[0088] L = P in +CP tr +S (7)

[0089] In the formula: L is the energy load vector; P in C is the energy injection vector; P is the energy coupling matrix; tr S is the energy coupling vector; S is the energy storage power vector.

[0090] Step 2: Combine the whole life cycle analysis method with the carbon quota trading mechanism to construct a carbon trading model for the integrated energy system.

[0091]

[0092] In the formula: the positive and negative values ​​of f2 represent the buying and selling of carbon emission credits, the former being the additional cost and the latter being the profit. Cost per unit of carbon; K 1,i K represents the total carbon dioxide emissions of equipment i during actual operation. 2,i The carbon emission allowance for a given object i.

[0093] The LCA energy chain of the IES reflects the carbon emissions of corresponding operating equipment at each stage of different energy production, transportation, and use environments. The carbon emission coefficients of the main links in the system are represented by formula (9):

[0094] K 1,i =K 1,pi +K 1,ti +K 1,gi (9)

[0095] In the formula: K 1,i K represents the total carbon emission coefficient of the energy chain for energy device i and its corresponding energy type, in g / (kW·h); 1,pi K represents the total carbon emission coefficient of the corresponding energy type production process for energy equipment i; 1,ti The total carbon emission coefficient of energy equipment i for the corresponding energy type storage stage, in g / (kW·h); K 1,gi The total carbon emissions of energy equipment i at the corresponding energy type usage stage, in g / (kW·h).

[0096] Step 3: Based on the dynamic energy hub state transition model of the integrated energy system and the carbon trading model of the integrated energy system, construct a low-carbon economic optimization scheduling model for the integrated energy system, and solve for the low-carbon economic scheduling strategy considering the variable operating conditions of the energy conversion equipment.

[0097] The integrated energy system scheduling model, which takes into account the variable operating conditions of energy conversion equipment, aims to minimize the sum of the conventional operating cost, carbon emission cost, and variable operating condition correction cost of the integrated energy system.

[0098] min f=f1+f2+f3 (10)

[0099] In the formula: f is the total cost of IES; f1 is the conventional operating cost; f2 is the carbon emission cost; and f3 is the cost of adjusting for different operating conditions.

[0100]

[0101] In the formula: C(t) is the unit energy purchase cost at time t, including the unit electricity purchase cost C. grid (t), Unit gas purchase cost C gas (t); P b (t) represents the energy purchased during time period t, including the purchased power P. buy (t), Gas purchasing power G buy (t); Δt is the duration of the scheduling period; N w The number of maintenance equipment; Unit equipment maintenance cost; P i (t) represents the operating power of device i during time period t.

[0102]

[0103] In the formula: L n The required response load for the IES is denoted by n, which includes four energy sources: electricity, gas, heat, and cooling, and L represents the time period t. n The unit correction cost includes the unit energy correction cost C. e (t), Unit additional carbon emission cost For time period t, due to L n The corrective power resulting from the difference between the scheduled power and the actual power.

[0104] The integrated energy system low-carbon economic dispatch model considering the variable operating conditions of energy conversion equipment has the following constraints:

[0105] 1) Constraints of energy storage devices:

[0106] Energy storage devices mainly include electrical storage devices and thermal storage devices. The operating status of energy storage devices mainly considers two states: charging and discharging. The state of charge (SOC) adopts a general mathematical model, as shown in equation (13-21), and sets the boundary of the number of energy storage charge and discharge cycles to alleviate the energy interaction pressure of energy storage devices.

[0107]

[0108] SOC min ≤SOC0≤SOC max (14)

[0109] SOC min ≤SOC t ≤SOC max (15)

[0110]

[0111]

[0112]

[0113]

[0114]

[0115]

[0116] Where: SOC t The energy state at time t is the energy stored; δ ES The self-discharge rate of the energy storage device; SOC0, SOC max SOCmin These are the initial, upper, and lower limits of the energy storage state, respectively. η represents the charging and discharging power of the energy storage device at time t, respectively; ES,s η ES,r These represent the charging and discharging efficiencies of energy storage devices, respectively; S es This refers to the rated capacity of the energy storage device. All are binary variables, when releasing energy When the value is 1, energy is stored. A value of 1 is used to limit the operating state of energy storage devices, P ES The rated power of the energy storage Let t represent the energy storage charging / discharging power during time period t. n represents the maximum number of charging / discharging cycles for the energy storage device per day.

[0117] 2) Constraints on energy conversion equipment:

[0118] The output constraints for the operating boundaries of all energy conversion devices in the system are shown in equation (22).

[0119]

[0120] In the formula: P α,t The set representing the energy output of device α at time t includes CHP, GB, EC, and AC. and These represent the upper and lower limits of the energy output of device α.

[0121] 3) Constraints on energy supply and demand balance:

[0122] Based on the matrix form of the energy hub variable operating condition model in equation (5), it can be expanded into the energy supply and demand balance constraint shown in equation (23).

[0123]

[0124] In the formula: L e,t L g,t L h,t L c,t These represent the electrical load, gas load, heat load, and cooling load at time t, respectively. Let t be the input power of the energy conversion device at time t.

[0125] Thus, a low-carbon economic dispatch method for integrated energy systems, taking into account the variable operating conditions of energy conversion equipment, has been established. The low-carbon economic dispatch scheme for the integrated energy system can then be obtained by solving the model using the Gurobi solver on the PyCharm platform.

[0126] Application Example 1:

[0127] To further understand the present invention, the following uses a day-ahead integrated energy system incorporating new energy sources as an example to explain the practical application of the present invention.

[0128] The integrated energy system structure includes electricity, gas, heat, and cooling, with these four energy sources interconnected and including renewable energy (wind power and photovoltaic power). The distribution network, natural gas network, heating network, and cooling network are connected via a combined heat and power (CHP) unit, a gas-fired boiler (GB), an electric chiller (EC), and an absorption chiller (AC) within the energy hub. Energy storage devices include electrical storage and thermal storage devices. A detailed integrated energy structure diagram is shown below. Figure 2 As shown.

[0129] The optimal scheduling strategies for power networks, hot networks, and cold networks in IES are as follows: Figures 3-5 As shown. First, there's the heating network. Due to the multi-energy coupling characteristics of CHP, its comprehensive energy utilization capacity is superior to GB. Consequently, CHP operates at almost full capacity throughout the energy production period, while GB handles the low electricity price range. When CHP is not at full capacity, GB assists in supplying heat energy to the heating network. Second, there's the cooling network. From 10:00 to 12:00, the overall cooling load demand is not high compared to the rated capacity of the AC cooling energy supply equipment, resulting in lower AC variable operating efficiency. Therefore, EC becomes the main supplier of cooling energy. However, at 13:00, the electricity price is much higher than the gas price, and with the increased participation of CHP units, the heating network has surplus heat energy. AC has better energy utilization efficiency than EC. The introduction of carbon quotas has increased the participation of CHP units in energy production, reducing the carbon emissions generated by system operation.

[0130] Table 1 presents the optimization results for three scenarios: one without considering the variable operating conditions of the energy conversion equipment in the IES and without considering the carbon emission cost of the system; one considering the variable operating conditions of the energy conversion equipment in the IES but without considering the carbon emission cost of the system; and one considering the carbon emission cost based on Scenario II and introducing a carbon quota system to settle the carbon emission cost. Energy correction costs are included in the regular operating costs, and variable operating condition correction costs are included in the total cost. As shown in Table 1, in Scenario I, the optimized operating costs considering the variable operating condition efficiency model and the constant parameter efficiency model of the energy conversion equipment are RMB 39,995.165 and RMB 43,062.149, respectively, with carbon emissions of 103.349t and 107.464t, respectively. The latter is significantly better than the former in terms of both economic and environmental benefits. However, in actual operating conditions, the operating efficiency of the equipment cannot always remain at the rated value, and the nonlinear operating characteristics of the energy conversion equipment need to be fully considered. Therefore, variable operating condition corrections are applied to the optimization results of Scenario I. Insufficient electrical energy is supplemented by purchasing electricity from the external grid, and other insufficient energy is supplemented by external equipment. Table 1 also shows that, based on Scenario II and further considering carbon costs, the system operating cost in Scenario III increased from RMB 43,062.149 to RMB 43,063.913, an increase of 0.004%; carbon emissions decreased from 107.464t to 107.386t, a decrease of 0.0725%; and the total cost decreased from RMB 66,704.389 to RMB 53,403.125, a decrease of 19.94%, due to the provision of free carbon allowances. Given the free carbon allowance coefficients for various types of equipment within the system, among the energy-consuming equipment in the heating network, CHP units obtained more additional carbon allowances compared to GB units, making them more motivated to participate in IES energy interaction.

[0131] Table 1

[0132]

[0133] Figures 6-7 This displays the state diagrams of energy storage and thermal storage devices in a low-carbon economic dispatch model for an integrated energy system that takes into account the variable operating conditions of energy conversion equipment. From... Figure 6It can be seen that due to the existence of time-of-use energy pricing, the activity of each energy storage device in the system participating in energy response is enhanced. Energy storage devices are highly sensitive to peak electricity prices. Before the peak electricity price arrives, the energy storage devices begin to gradually store energy, thereby discharging it during the peak electricity price period, alleviating peak loads, achieving spatiotemporal energy shifting, reducing energy costs, and playing a role in peak shaving and valley filling. Although the heating network is more affected by gas prices, there is a clear following behavior between thermal energy storage devices and electrical energy storage devices. This is mainly because the increase in output of CHP units leads to a thermal energy surplus in the system. However, as the electrical energy in the network is consumed by the energy storage devices, more space is provided for the production of CHP units, while the thermal energy storage devices take on the task of consuming the surplus thermal energy.

[0134] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A low-carbon economic dispatch method for a comprehensive energy system considering variable operating characteristics of energy conversion equipment, characterized in that: Includes the following steps: S1: Combining the variable operating condition characteristics of energy conversion equipment in the integrated energy system with the static energy hub, a dynamic energy hub state transition model for the integrated energy system is constructed; step S1, constructing the dynamic energy hub state transition model for the integrated energy system, includes: S11: Modeling the variable operating condition characteristics of energy conversion equipment in an integrated energy system, represented as: In the formula: For CHP variable operating condition electrical efficiency. For CHP variable operating condition thermoelectric ratio, For GB variable operating condition efficiency. For AC variable operating condition efficiency; These are the fitting coefficients for the CHP variable operating condition electrical efficiency. The fitting coefficients for the thermoelectric ratio under CHP variable operating conditions are: The fitting coefficients for GB variable operating condition efficiency are... Fitting coefficients for AC variable operating condition efficiency; p chp The electrical load factor of CHP. p gb The load rate is in GB. p ac The load factor of the AC; S12: Based on the static energy hub model of the integrated energy system, establish the dynamic energy hub state transition model of the integrated energy system: In the formula: L e , L g , L h , L c For load demand; , , , Input power to the energy source; , These are the CHP unit's power conversion efficiency and the CHP unit's heat-to-power ratio, respectively. , , The energy conversion efficiencies are GB, EC, and AC, respectively. , , , These are the input power of the energy conversion equipment CHP, GB, EC, and AC, respectively. , , , These are the dispatch power of the energy storage device; In the formula: , The system uses externally sourced energy. P PV , P WT These represent the power output of photovoltaic power generation and wind power generation, respectively. S13: The state transition model of the dynamic energy hub of the integrated energy system is simplified as follows: In the formula: L This is the energy load vector; P in Inject energy into vectors; C This is the energy coupling relationship matrix; P tr This is the energy coupling vector; S For energy storage power vector; S2: Combine the whole life cycle analysis method with the carbon quota trading mechanism to construct a comprehensive energy system carbon trading model; S3: Based on the dynamic energy hub state transition model and the carbon trading model of the integrated energy system, a low-carbon economic dispatch model for the integrated energy system considering the variable operating conditions of energy conversion equipment is constructed, and the low-carbon economic dispatch strategy considering the variable operating conditions of energy conversion equipment is solved; the low-carbon economic dispatch model for the integrated energy system considering the variable operating conditions of energy conversion equipment has the following constraints: Constraints of energy storage devices: Where: SOC t For energy storage t Energy state at any given moment; The self-discharge rate of the energy storage device; SOC0, SOC max SOC min These are the initial, upper, and lower limits of the energy storage state, respectively. , For energy storage devices t The charging and discharging power at any given moment; , These refer to the charging and discharging efficiencies of energy storage devices, respectively. S es This refers to the rated capacity of the energy storage device. , All are binary variables, when releasing energy When the value is 1, energy is stored. A value of 1 is used to limit the operating status of energy storage devices. P ES The rated power of the energy storage for t Energy storage charging and discharging power during specific time periods; n This is the maximum number of times an energy storage device can be charged and discharged in a single day. Constraints of energy conversion equipment: For the operating boundaries of all energy conversion devices in the system, the output constraints are as shown in equation (22): In the formula: For equipment In t The energy output at any given time includes CHP, GB, EC, and AC. and respectively equipment The upper and lower limits of energy output; Energy supply and demand balance constraints: The matrix form of the energy hub variable operating condition model is expanded into the energy supply and demand balance constraint shown in equation (23): In the formula: , , , They are respectively t Real-time electrical load, gas load, heat load, and cooling load; , , , for t The input power of the energy conversion device at any given time.

2. The low-carbon economic dispatch method for integrated energy systems considering the variable operating conditions of energy conversion equipment as described in claim 1, characterized in that: The energy conversion equipment in the integrated energy system includes a combined heat and power unit, a gas boiler, an absorption chiller, and an electric chiller. The combined heat and power unit consists of a gas turbine and a waste heat boiler. The multiple energy storage devices in the integrated energy system include a storage generator set and a thermal storage unit.

3. The low-carbon economic dispatch method for integrated energy systems considering the variable operating conditions of energy conversion equipment as described in claim 1, characterized in that: The integrated energy system carbon trading model described in step S2 is as follows: In the formula: f The positive and negative values ​​of the two numbers represent the buying and selling of carbon emission credits; the former represents additional costs, while the latter represents the gains. Cost per unit of carbon K 1,i For equipment i Total carbon dioxide emissions during actual operation; K 2,i For a given object i Carbon emission allowance for the equipment; The carbon emission coefficient is quantified and characterized using formula (9): In the formula: K 1,i Indicates energy equipment i Total carbon emission coefficients of the energy chain for the corresponding energy type; K 1,pi For energy equipment i Total carbon emission coefficients for the corresponding energy type production process; K 1,ti For energy equipment i The total carbon emission coefficient of the corresponding energy type storage process; K 1,gi For energy equipment i Total carbon emissions at each stage of energy use.

4. The low-carbon economic dispatch method for integrated energy systems considering the variable operating conditions of energy conversion equipment according to claim 1, characterized in that: Step S3, based on the dynamic energy hub state transition model and the carbon trading model of the integrated energy system, constructs a low-carbon economic optimization scheduling model for the integrated energy system, and solves for a low-carbon economic scheduling strategy considering the variable operating characteristics of energy conversion equipment, including: The integrated energy system low-carbon economic dispatch model, which takes into account the variable operating conditions of energy conversion equipment, aims to minimize the sum of the conventional operating costs, carbon emission costs, and variable operating condition correction costs of the integrated energy system. In the formula: f This represents the total cost of IES; f 1 represents the standard operating cost; f 2 represents the cost of carbon emissions; f 3 represents the cost of adjusting for varying operating conditions; In the formula: C ( t )for t The unit energy purchase cost at any given time includes the unit electricity purchase cost. C grid ( t Unit gas purchase cost C gas ( t ); P b ( t )for t Time-based energy purchase capacity, including electricity purchase capacity P buy ( t ), gas purchasing power G buy ( t ); The duration of the scheduling period; N w The number of maintenance equipment; Unit equipment operation and maintenance cost; P i ( t )for t Time-of-use equipment i Operating power; In the formula: L n Set up the required response load for IES n It includes four energy sources: electricity, gas, heat, and cooling. t Time period L n The unit correction cost includes the unit energy correction cost C. e ( t Unit additional carbon emission cost , for t Time period due to L n The corrective power resulting from the difference between the scheduled power and the actual power.

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