Multi-park comprehensive energy system energy scheduling method considering heat energy quality

Abstract

The invention discloses a multi-park integrated energy system energy scheduling method considering heat energy quality, which comprises the following steps: forming a high-energy-consumption park by high-energy-consumption equipment, forming a low-energy-consumption park by low-energy-consumption equipment, and establishing an output model and a waste heat interaction device model of the equipment; constructing a high-energy-consumption park model and a low-energy-consumption park model; establishing heat energy income balance between the high-energy-consumption park and the low-energy-consumption park, and interconnecting the high-energy-consumption park and the low-energy-consumption park; establishing a comprehensive energy operator benefit model; establishing a master-slave game model of the integrated energy operator and the park integrated energy system cluster and a cooperative game model among members of the park integrated energy system cluster, and respectively taking benefit maximization of the integrated energy operator and cost minimization of the members of the park integrated energy system cluster as objective functions; and solving the game model to obtain the optimal energy scheduling method of the multi-park integrated energy system. And the matching between different grades of heat energy and heat supply requirements is enhanced, so that the gradient utilization efficiency of the heat energy is further improved.

Description

Technical Field

[0001] The present invention relates to a power system and an integrated energy system, and more particularly to an energy scheduling method for a multi-park integrated energy system considering the quality of thermal energy. Background Art

[0002] A park integrated energy system (PIES) is a system that integrates and coordinates multiple types of energy, and its characteristic is to improve energy efficiency on a large scale. In the optimization scheduling model of the integrated energy system, the reuse of waste heat through energy cascade utilization technology is an effective way for multiple independent energy systems to improve energy utilization efficiency and reduce operating costs. High-energy-consuming park integrated energy systems represented by steel plants generate a large amount of high-quality thermal energy, and recovering this high-quality thermal energy is an effective method to improve energy efficiency and reduce the use of fossil fuels. Low-energy-consuming parks represented by food processing plants have different thermal load users, and require thermal energy with different flow rates and multiple grades of quality. With the increase in the number of park integrated energy systems, adjacent parks are interconnected to form an integrated energy systems cluster (IESC), and the collaborative complementarity and interconnection of various energies are realized through energy sharing between parks. Since each park integrated energy system involves different stakeholders, it is crucial to design an effective trading strategy to achieve the sharing of electric energy and thermal energy between park clusters.

[0003] Existing research mostly adjusts the quality thermal energy at different temperatures by methods such as throttling or cooling to meet the thermal demands corresponding to different loads. In addition, for park integrated energy systems, most research is limited to a single type of electric energy sharing strategy, and in the collaborative optimal scheduling of park integrated energy systems, the optimization objectives of the upper-layer leader model and the lower-layer follower model established by game theory mostly aim to maximize their respective interests.

[0004] The current waste heat interaction methods mainly focus on the recovery methods considering a single user and a single waste heat source. In reality, industrial parks are composed of numerous industrial users, and these users have different waste heat grades and require different grades of quality thermal energy. The point-to-point waste heat utilization method is not sufficient to meet the requirements of the industrial park scenario, which results in a mismatch between waste heat and thermal users in terms of temperature, thereby increasing the grade loss of quality thermal energy.

[0005] The research on multi-park integrated energy systems focuses on the energy interaction between each park as a whole and an integrated energy service provider (IESP), without considering the individual interests of each park itself, which will weaken the potential of demand response of each park and reduce the operating economy of each park. Summary of the Invention

[0006] Objective of the Invention: Aiming at the above-mentioned shortcomings, the present invention provides an energy scheduling method for multi-park integrated energy systems that takes into account the heat energy quality, which makes full use of the heat energy in the park integrated energy system and solves the problem that economy and energy utilization efficiency cannot be taken into account simultaneously during the optimization process of the park integrated energy system.

[0007] Technical Solution: To solve the above problems, the present invention adopts an energy scheduling method for multi-park integrated energy systems that takes into account the heat energy quality, including the following steps:

[0008] (1) According to the heat energy quality of the equipment, the equipment is divided into high-energy-consuming equipment and low-energy-consuming equipment. The high-energy-consuming equipment forms a high-energy-consuming park, and the low-energy-consuming equipment forms a low-energy-consuming park. An output model of the equipment and a waste heat interaction device model are established.

[0009] (2) The high-energy-consuming park and the low-energy-consuming park are interconnected through a waste heat interaction device. According to the output model of the equipment and the waste heat interaction device model, a heat energy revenue balance is established between the high-energy-consuming park and the low-energy-consuming park.

[0010] (3) According to the output model of the high-energy-consuming equipment, the total operating cost of the park integrated energy system is calculated, and a high-energy-consuming park model is constructed; according to the output model of the low-energy-consuming equipment, the total operating cost of the park integrated energy system is calculated, and a low-energy-consuming park model is constructed.

[0011] (4) According to the income from power purchase and power sale between the integrated energy operator and the superior power grid, and the income from power purchase and power sale between the integrated energy operator and the park integrated energy system cluster, an integrated energy operator benefit model is established; the park integrated energy system cluster includes a high-energy-consuming park and a low-energy-consuming park.

[0012] (5) Based on the high-energy-consuming park model, the low-energy-consuming park model, the integrated energy operator benefit model, and the energy transaction between the high-energy-consuming park and the low-energy-consuming park, a master-slave game model of the integrated energy operator and the park integrated energy system cluster and a cooperative game model among the members of the park integrated energy system cluster are established, with the maximization of the integrated energy operator benefit and the minimization of the own cost of the members of the park integrated energy system cluster as the objective functions respectively.

[0013] (6) The bisection method is used to solve the master-slave game model of the integrated energy operator and the park integrated energy system cluster, and the ADMM algorithm is used to solve the cooperative game model among the members of the park integrated energy system cluster to obtain the optimal energy scheduling method for the multi-park integrated energy system.

[0014] Furthermore, the high-energy-consuming equipment includes a cogeneration device. When establishing the output model of the cogeneration device, an organic Rankine cycle is introduced to convert the excess waste heat into electric energy, and an improved cogeneration model is established:

[0015]

[0016] Wherein, is the thermal power output by the gas turbine within time t, and are respectively the thermal powers input into the waste heat boiler and the organic Rankine cycle within time t, and are respectively the output thermal powers of the organic Rankine cycle and the waste heat boiler within time t, δ ORC,i is the conversion efficiency of the organic Rankine cycle, δ WHB,i is the heat loss of the waste heat boiler, and are the upper and lower limits of the input power of the organic Rankine cycle within time t, and are the upper and lower limits of the ramp of the organic Rankine cycle within time t;

[0017] Finally, the thermal and electric output powers of the improved cogeneration are:

[0018]

[0019] Wherein, is the electric output power of the improved cogeneration within time t, and are respectively the electric power outputs of the organic Rankine cycle and the micro gas turbine within time t, is the thermal output power of the improved cogeneration within time t, is the thermal output power of the waste heat boiler within time t.

[0020] Furthermore, the low-energy-consuming equipment includes a heat pump, and the heat pump includes a compression heat pump MHP, a heat amplification absorption heat pump AHP, a temperature-raising absorption heat converter AHT, a high-temperature heat pump HHP, and a gas boiler GB;

[0021] The model of the compression heat pump MHP is:

[0022]

[0023] Wherein, is the electric power input by the MHP within time t, is the low-grade heat energy input by the MHP within time t, μ MHP,i is the efficiency conversion coefficient of the MHP. When α MHP,t = 0.7, βMHP,t = 0.8, are the input temperature of the condenser and the output temperature of the evaporator at time t, respectively, is the coefficient of performance under the actual operating condition of the MHP;

[0024] The model of the heat amplification type absorption heat pump AHP is:

[0025]

[0026] where, is the electric power input to the AHP at time t, is the low-grade heat energy input to the AHP at time t, μ AHP,i is the efficiency conversion coefficient of the AHP, is the coefficient of performance under the actual condition of the AHP, is the coefficient of performance of the AHP under the ideal condition, is the generator temperature at time t, is the evaporator temperature at time t, is the condenser temperature at time t;

[0027] The model of the temperature-raising absorption heat converter AHT is:

[0028]

[0029] where, is the low-grade heat energy input to the AHT at time t, is the operating coefficient under the actual condition of the AHT, μ AHT,i is the efficiency conversion coefficient of the AHT, is the coefficient of performance of the AHT under the ideal condition, generator temperature at time t, is the evaporator temperature at time t, is the condenser temperature at time t, is the absorber temperature at time t;

[0030] The model of the high-temperature heat pump HHP is:

[0031]

[0032] where, is the electric power input to the HHP at time t, is the low-grade heat energy input to the HHP at time t, is the coefficient of performance under the actual operating condition of the HHP, μ HHP,i is the efficiency conversion coefficient of the HHP, is the evaporator temperature at time t, is the temperature of the condenser at time t;

[0033] The model of the gas boiler GB is:

[0034]

[0035] where, is the natural gas consumption of GB within time t, is the thermal energy output power of GB within time t, δ GB,i is the energy conversion efficiency of GB, is the upper and lower limits of the natural gas consumption of GB at time t.

[0036] Further, the model of the waste heat interaction device is:

[0037]

[0038] where, is the thermal energy interaction power between low-energy consumption parks, and are the thermal energy output powers of HR-WHRD and HE-WHRD respectively within time t, and are the thermal energy input powers of HR-WHRD and HE-WHRD respectively within time t, is the high-grade thermal energy obtained by the low-energy consumption park from the high-energy consumption park within time t, δ HR,i and δ HE,i are the energy conversion efficiencies of the heat recovery device and the heat exchanger respectively, and are the upper and lower limits of the thermal energy input power of HE-WHRD at time t.

[0039] Further, the establishment of the thermal energy revenue balance between the high-energy consumption park and the low-energy consumption park is specifically:

[0040]

[0041] where, represents the thermal output power of improving the combined heat and power generation within time t, that is, the high-grade thermal energy generated by the high-energy consumption park within time t, represents the high-grade thermal energy demand of the high-energy consumption park, represents the thermal energy flowing from the high-energy consumption park to the low-energy consumption park within time t.

[0042] Further, the objective function in the model of the high-energy consumption park is:

[0043]

[0044] Among them, is the total operating cost of the high - energy - consumption park, C g,ele,i,t is the cost of purchasing electricity, C g,gas,i,t is the cost of purchasing natural gas, C g,equ,i,t is the component operation and maintenance cost are respectively the prices of purchasing electricity and natural gas by the high - energy - consumption park within time t is the electric power purchased by the high - energy - consumption park within time t is the natural gas purchased by the high - energy - consumption park within time t

[0045] The objective function of the low - energy - consumption park model is:

[0046]

[0047] Among them, is the total operating cost of the low - energy - consumption park, C d,ele,i,t is the cost of purchasing electricity of the low - energy - consumption park, C d,heat,i,t is the cost of purchasing heat from the high - energy - consumption park by the low - energy - consumption park, C d,gas,i,t is the cost of purchasing natural gas of the low - energy - consumption park, C d,equ,i,t is the operation and maintenance cost of the low - energy - consumption park are respectively the prices of purchasing electricity and natural gas by the low - energy - consumption park within time t is the electric power purchased by the low - energy - consumption park within time t is the natural gas purchased by the low - energy - consumption park within time t is the price of purchasing heat energy from the high - energy - consumption park by the low - energy - consumption park within time t is the heat power purchased by the low - energy - consumption park from the high - energy - consumption park within time t

[0048] Furthermore, the comprehensive energy operator's interest model is:

[0049]

[0050] Among them, is the income of the comprehensive energy operator within time t and are respectively the on - grid electricity price and the grid electricity price within time t and are respectively the electricity sold to the superior grid and the electricity purchased within time t and are the electricity purchase and sale prices set by the comprehensive energy operator for the high - and low - energy - consumption parks within time t and are respectively the electricity sold and the electricity purchased by the high - and low - energy - consumption parks within time t

[0051] Furthermore, the master-slave game model between the integrated energy operator and the park integrated energy system cluster is:

[0052]

[0053] in, is the interaction cost between the integrated energy system cluster and the integrated energy operator in time t, C grid,i,t is the electricity purchase cost of the park integrated energy system cluster within time t, C fuel,i,t is the fuel cost consumed in the park integrated energy system cluster within time t, C trade,i,t is the energy sharing cost of the park integrated energy system cluster within time t, C gd,equ,i,t is the equipment maintenance cost of the integrated energy system cluster in the park within time t, including the operation and maintenance cost of equipment in high-energy consumption parks, the operation and maintenance cost of equipment in low-energy consumption parks, and the operation and maintenance cost of waste heat interaction devices. is the total natural gas demand of the park's integrated energy system cluster in period t, is the price paid per unit of electricity when a high-energy consumption park interacts with a low-energy consumption park. is the price paid per unit of thermal energy when a high-energy consumption park interacts with a low-energy consumption park, is the energy transaction volume between the high energy consumption park and the low energy consumption park in time t, is the heat energy trading volume between the high-energy consumption park and the low-energy consumption park in time t.

[0054] Furthermore, the cooperative game model among the members of the park integrated energy system cluster is:

[0055]

[0056] Among them, U i The benefits of participating in the negotiation for the park's integrated energy system cluster, The benefits of participating in the pre-negotiation negotiations for the integrated energy system cluster of the park;

[0057] Maximizing cluster benefits:

[0058]

[0059] Maximizing Energy Trading Profits:

[0060]

[0061] Among them, δ i represents the optimal solution for payment of electricity and heat transactions, C 0 Indicates the base cost.

[0062] Furthermore, the bisection method is adopted to solve the master-slave game between the integrated energy operator and the integrated energy system cluster in the park, which is specifically as follows:

[0063] Let be the energy price within time t in the nth iteration. If is the lower limit at this time, then when

[0064]

[0065] Add the constraint condition:

[0066]

[0067] If

[0068]

[0069] Add the constraint condition:

[0070]

[0071] Each iteration shrinks the iteration interval. At the same time, each iteration will judge whether the result meets the convergence condition. If it converges, the iteration ends;

[0072] The convergence condition is:

[0073]

[0074] Among them, and are the electricity purchase and sale prices set by the integrated energy operator for the integrated energy system cluster in the park at time t in the nth iteration, respectively. δ is the convergence criterion;

[0075] The specific solution steps for solving the cooperative game model among the members of the integrated energy system cluster in the park by using the ADMM algorithm are as follows:

[0076] ① Initialize the iteration number n = 1, the penalty factors ρ e,0 , ρ h,0 , the convergence criteria ε p , ε d , and the Lagrange multiplier Initialize the decision variables of high- and low-energy consumption parks

[0077] ② Obtain the expected transaction heat and the transaction electricity quantity Solve them to obtain the expected transaction heat and the transaction electricity quantity Update the penalty factors ρ e,n+1 , ρ h,n+1 ;

[0078] ③Judge whether the primal residual and the dual residual meet the convergence criteria; if the conditions are met, end the iteration, and the decision variables of the high- and low-energy consumption parks at this time are the minimum adjustable equipment adjustment solutions that meet the operating costs of the high- and low-energy consumption parks; if the conditions are not met, continue to step ④;

[0079]

[0080] Among them, r n+1 , d n+1 are the primal residual and the dual residual respectively;

[0081] ④Set the iteration number n=n+1, update the penalty factors and the decision variables of the high- and low-energy consumption parks. The iterative update formulas for the decision variables of the high- and low-energy consumption parks are as follows:

[0082]

[0083] Update the Lagrange multiplier The iterative update formula for the Lagrange multiplier is:

[0084]

[0085] Among them, are the decision variables of the high- and low-energy consumption parks in the nth iteration, ρ e,n , ρ h,n are the penalty factors of electricity and heat in the nth iteration respectively, are the Lagrange multipliers of electricity and heat in the nth iteration respectively, is the introduced auxiliary variable;

[0086] Return to step ② and continue to execute.

[0087] Advantageous effects: Compared with the prior art, the significant advantage of the present invention is that in order to achieve an efficient matching between different-quality heat energy and load, a new method for integrating the comprehensive energy waste heat utilization network of a park centered on a heat pump is proposed. This system can enhance the matching between different-grade heat energy and heating demand, thereby further improving the efficiency of cascade utilization of heat energy.

[0088] In terms of optimizing the operation strategy of the PIES, the master-slave game between the integrated energy operator and the integrated energy system cluster of the park is nested into the cooperative game between the integrated energy system clusters of the park, realizing the trading of electric energy and heat energy between microgrids, improving the energy utilization efficiency, and balancing the interests of all parties. BRIEF DESCRIPTION OF THE DRAWINGS

[0089] Figure 1 The figure shows the overall flow chart of the energy scheduling method in the present invention. Specific implementation mode

[0090] As Figure 1 shown, an energy scheduling method for a multi-park integrated energy system considering the quality of thermal energy in this embodiment includes the following steps:

[0091] Step 1: Establish an improved combined heat and power model. The combined heat and power equipment forms a high-energy-consuming park. The power generation of the traditional combined heat and power is equivalent to the heat supply. At the same time, an organic Rankine cycle is introduced to convert the excess waste heat into electric energy. The micro gas turbine (MGT), waste heat boiler (WHB), and organic Rankine cycle (ORC) are allocated according to the equivalent heat supply and power supply.

[0092] The corresponding mathematical expression is:

[0093]

[0094] Among them, is the thermal power output by the gas turbine at time t, and are the thermal powers input to the waste heat boiler and the organic Rankine cycle at time t respectively, and are the output thermal powers of the organic Rankine cycle and the waste heat boiler at time t respectively. δ ORC,i is the conversion efficiency of the organic Rankine cycle, and δ WHB,i is the heat loss of the waste heat boiler, and are the upper and lower limits of the input power of the organic Rankine cycle at time t, and are the upper and lower limits of the ramp of the organic Rankine cycle at time t.

[0095] The final thermal and electric output powers of the improved combined heat and power are:

[0096]

[0097] Among them, is the electric output power of the improved combined heat and power at time t, and are the electric power outputs of the organic Rankine cycle and the micro gas turbine at time t respectively, is the thermal output power of the improved combined heat and power at time t, is the thermal output power of the waste heat boiler at time t.

[0098] Low-energy-consuming devices form a low-energy-consuming park. The low-energy-consuming park has different-grade heat load demands. A heat pump network model is established. The heat pump heats or cools the temperature to make the temperature match the heat demand of the load. The heat energy flow of the low-energy-consuming park is reflected through the heat pump network. The mathematical expression for establishing the heat pump network model is as follows:

[0099] 1. Mechanical heat pump (MHP)

[0100]

[0101] Among them, is the electric power input by the MHP at time t, is the low-grade heat energy input by the MHP at time t, μ MHP,i is the MHP efficiency conversion coefficient. When α MHP,t = 0.7, β MHP,t = 0.8, are the input temperature of the condenser and the output temperature of the evaporator at time t respectively, is the coefficient of performance of the MHP under the actual operating condition, which needs to be updated when the input and output temperatures change.

[0102] 2. Heat-amplifying absorption heat pump (AHP)

[0103]

[0104] Among them, is the electric power input by the AHP at time t, is the low-grade heat energy input by the AHP at time t, μ AHP,i is the AHP efficiency conversion coefficient, is the coefficient of performance of the AHP under the actual condition, is the coefficient of performance of the AHP under the ideal condition, is the generator temperature at time t, is the evaporator temperature at time t, is the condenser temperature at time t. It should be noted that the condensation and evaporation temperatures are considered as the output temperatures, while the generator temperature is considered as the input temperature.

[0105] 3. Temperature-lifting absorption heat transformer (AHT)

[0106]

[0107] Among them, is the low-grade thermal energy input by AHT within time t, is the operation coefficient of AHT in the actual state, μ AHT,i is the efficiency conversion coefficient of AHT, is the coefficient of performance of AHT in the ideal state, is the temperature of the generator within time t, is the temperature of the evaporator within time t, is the temperature of the condenser within time t, is the temperature of the absorption tower within time t.

[0108] 4. High temperature heat pump (HHP)

[0109]

[0110] Among them, is the electric power input by MHP within time t, is the low-grade thermal energy input by HHP within time t, is the coefficient of performance of HHP in the actual operation state, β HHP,i is the efficiency conversion coefficient of HHP, is the temperature of the evaporator within time t, is the temperature of the condenser within time t.

[0111] 5. Gas boiler (GB)

[0112]

[0113] Among them, is the natural gas consumption of GB within time t, is the thermal energy output power of GB within time t, δ GB,i is the energy conversion efficiency of GB, is the upper and lower limits of the natural gas consumption of GB within time t.

[0114] Step 2: Connect the high-energy-consuming park and the low-energy-consuming park through the waste heat interaction device. The waste heat interaction device (WHRD) mainly consists of a heat recovery device (HR-WHRD) and a heat exchanger (HE-WHRD) in the WHRD. The low-energy-consuming park can recover the waste heat of the high-energy-consuming park through the heat exchanger and transfer its own remaining waste heat to other low-energy-consuming parks through the heat recovery device.

[0115] Establish a waste heat interaction device model:

[0116]

[0117] Without considering heat energy loss, the waste heat interaction device is expressed as

[0118]

[0119] where is the heat energy interaction power between the parks, and are the heat energy output powers of HR-WHRD and HE-WHRD respectively within time t, is the high-grade heat energy obtained by the low-energy consumption park from the high-energy consumption park within time t, and are the heat energy input powers of HR-WHRD and HE-WHRD respectively within time t, δ HR,i and δ HE,i are the energy conversion efficiencies of HR-WHRD and HE-WHRD respectively, and are the upper and lower limits of the heat energy output power of HE-WHRD within time t.

[0120] Establish a heat energy revenue balance model between high and low energy consumption parks. Connect the high energy consumption park and the low energy consumption park to realize the cascade utilization of heat energy.

[0121]

[0122] where represents the heat output power of improving cogeneration within time t, that is, the high-grade heat energy generated by the high energy consumption park within time t, represents the high-grade heat energy demand of the high energy consumption park, represents the heat energy flowing from the high energy consumption park to the low energy consumption park within time t.

[0123] Step 3: Establish a high energy consumption park model. The high energy consumption park purchases electricity and natural gas to supply the cogeneration equipment to generate high-grade heat energy. According to the output model of the high energy consumption equipment, calculate the total operating cost of the park's integrated energy system, and construct a high energy consumption park model so that the total operating cost of PIES represented by the high energy consumption park includes the cost of purchasing electricity, the cost of purchasing natural gas, and the component operation and maintenance costs. The objective function formula of the high energy consumption park is:

[0124]

[0125] where is the total operating cost of the high energy consumption park, Cg,ele,i,t is the cost of the power grid purchasing electricity, C g,gas,i,t is the cost of purchasing natural gas from the natural gas network, C g,equ,i,t is the component operation and maintenance cost are the prices of purchasing electricity and natural gas by the high-energy consumption park within time t respectively is the electric power purchased by the high-energy consumption park within time t is the natural gas purchased by the high-energy consumption park within time t

[0126] Establish a low-energy consumption park model. The low-energy consumption park supplies a heat pump device by purchasing electricity and natural gas to generate low-grade heat energy with the heat pump device. According to the output model of the low-energy consumption device, calculate the total operating cost of the park's integrated energy system. Construct a low-energy consumption park operating cost model so that the total daily operating cost of the PIES represented by the low-energy consumption park. The mathematical model is expressed as:

[0127]

[0128] Among them, is the total operating cost of the low-energy consumption park, C d,ele,i,t is the cost of the low-energy consumption park purchasing electricity, C d,heat,i,t is the cost of the low-energy consumption park purchasing heat from the high-energy consumption park, C d,gas,i,t is the cost of the low-energy consumption park purchasing natural gas, C d,equ,i,t is the operation and maintenance cost of the low-energy consumption park are the prices of purchasing electricity and natural gas by the low-energy consumption park within time t respectively is the electric power purchased by the low-energy consumption park within time t is the natural gas purchased by the low-energy consumption park within time t is the price of the low-energy consumption park purchasing heat energy from the high-energy consumption park within time t is the heat power purchased by the low-energy consumption park from the high-energy consumption park within time t

[0129] Step 4: Establish an electric energy interaction model between the integrated energy operator and the park. It includes the income from power purchase and sale between the integrated energy operator and the superior power grid, as well as the income from power purchase and sale between the integrated energy operator and the park integrated energy system cluster. The park integrated energy system cluster includes high-energy consumption parks and low-energy consumption parks

[0130]

[0131] Among them, is the income of the integrated energy operator within time t and are the on-grid electricity price and the grid electricity price within time t respectively and are the electricity sales volume and electricity purchase volume from the superior power grid within time t respectively, and are the electricity purchase and sales prices set by the integrated energy operator for the integrated energy system cluster in the park at time t, and are the electricity sales volume and electricity purchase volume of the integrated energy system cluster in the park within time t respectively.

[0132] The electricity purchase and sales prices formulated by the integrated energy operator should be within a certain limit range, that is:

[0133]

[0134] Among them, and are the upper and lower limits of the electricity purchase price of the integrated energy operator from the integrated energy system cluster in the park respectively, and are the upper and lower limits of the electricity sales price of the integrated energy operator to the integrated energy system cluster in the park respectively.

[0135] Step 5: Establish a master-slave game model for the integrated energy operator and the integrated energy system cluster in the park. As the leader of the master-slave game, IESP formulates the energy sales price and energy sales strategy to the integrated energy system cluster in the park according to the energy purchase strategy reported by the integrated energy system cluster in the park.

[0136]

[0137] Among them, is the interaction cost between the integrated energy system cluster in the park and the integrated energy operator within time t, C grid,i,t is the electricity purchase cost in the integrated energy system cluster in the park within time t, C fuel,i,t is the fuel cost consumed in the integrated energy system cluster in the park within time t, C trade,i,t is the energy sharing cost in the integrated energy system cluster in the park within time t, C gd,equ,i,t is the equipment maintenance cost in the integrated energy system cluster in the park within time t, including the operation and maintenance costs of equipment in high-energy-consuming parks, the operation and maintenance costs of equipment in low-energy-consuming parks, and the operation and maintenance costs of waste heat interaction devices, is the total natural gas demand of the integrated energy system cluster in the park in the t-th period, is the payment price per unit of electric energy when high-energy-consuming parks and low-energy-consuming parks interact, is the payment price per unit of thermal energy when high-energy-consuming parks and low-energy-consuming parks interact, is the energy trading volume between high-energy-consuming parks and low-energy-consuming parks within time t, is the thermal energy trading volume between the high - energy - consumption park and the low - energy - consumption park within time t.

[0138] Step 6: Establish a cooperative game model for the high - energy - consumption park and the low - energy - consumption park. As the followers of the leader - follower game, the high - energy - consumption park and the low - energy - consumption park optimize their energy procurement strategies, their own equipment production volumes, and the energy interaction value between IESs according to the energy sales strategies formulated by the integrated energy operator, and feedback the energy procurement strategies to the integrated energy operator. The high - energy - consumption park and the low - energy - consumption park establish a shared - cost optimization model for the multi - park integrated energy system with the goal of minimizing their own costs, as follows:

[0139]

[0140] where U i is the revenue after the high - energy - consumption park and the low - energy - consumption park participate in the negotiation, is the revenue before the high - energy - consumption park and the low - energy - consumption park participate in the negotiation, that is, the breakdown point C of the negotiation.

[0141] Sub - problem 1: Maximize the benefits of the high - energy - consumption park and the low - energy - consumption park

[0142]

[0143] In the formula, by minimizing to achieve the maximization of the benefits of the high - energy - consumption park and the low - energy - consumption park, indicating that the goal is to minimize the cost of each park as much as possible.

[0144] Sub - problem 2: Maximize the energy trading revenue

[0145]

[0146] In sub - problem 2, δ i represents the optimal solution of the payment cost for the electric - heat trading; C 0 represents the benchmark cost. When the high - energy - consumption park and the low - energy - consumption park conduct electric - heat sharing, in order to ensure maximum benefits, the high - energy - consumption park and the low - energy - consumption park will report cost information during the negotiation process and solve the above - mentioned model.

[0147] Step 7: The upper - layer model uses the bisection method to solve the leader - follower game between the integrated energy operator and the high - energy - consumption park and the low - energy - consumption park, and the lower - layer model uses the ADMM algorithm to solve the cooperative game between the high - energy - consumption park and the low - energy - consumption park to find the optimal energy management strategy.

[0148] Using the bisection method to solve the leader - follower game between the integrated energy operator and the high - energy - consumption park and the low - energy - consumption park is specifically as follows:

[0149] ① Let be the energy price within time t in the n - th iteration. If is the lower limit at this time, then when

[0150]

[0151] Add the constraint condition:

[0152]

[0153] If

[0154]

[0155] Add the constraint condition:

[0156]

[0157] ② Due to the constraint of ①, the iteration interval can be reduced in each iteration. At the same time, it is judged whether the result meets the convergence condition in each iteration. If it converges, the iteration ends.

[0158]

[0159] Among them, and are the electricity purchase and sale prices set by the integrated energy operator for the high - energy - consuming park and the low - energy - consuming park at time t in the nth iteration respectively, and δ is the convergence criterion.

[0160] The specific solution steps for solving the cooperative game model among the members of the integrated energy system cluster of the park using the ADMM algorithm are as follows:

[0161] ① Initialize the iteration number n = 1, the penalty factors ρ e,0 、ρ h,0 ,the convergence criteria ε p 、ε d ,and the Lagrange multiplier Initialize the decision variables of the high - and low - energy - consuming parks

[0162] ② Obtain the expected trading heat and trading electricity quantity Solve them to obtain the expected trading heat and trading electricity quantity Update the penalty factors ρ e,n+1 、ρ h,N+1 ;

[0163] ③ Judge whether the primal residual and dual residual meet the convergence criteria; if the conditions are met, end the iteration, and the decision variables of the high - and low - energy - consuming parks at this time The minimum adjustable device mediation solution to meet the operating costs of high- and low-energy consumption parks; if the conditions are not met, proceed to step ④;

[0164]

[0165] where r n+1 and d n+1 are the original residual and the dual residual respectively;

[0166] ④ Set the number of iterations n = n + 1, update the penalty factors and decision variables of high- and low-energy consumption parks. The iterative update formulas for the decision variables of high- and low-energy consumption parks are:

[0167]

[0168] Update the Lagrange multipliers The iterative update formula for the Lagrange multipliers is:

[0169]

[0170] where are the decision variables of high- and low-energy consumption parks at the nth iteration, ρ e,n and ρ h,n are the penalty factors of electricity and heat at the nth iteration respectively, are the Lagrange multipliers of electricity and heat at the nth iteration respectively, is the introduced auxiliary variable;

[0171] Return to step ② and continue to execute.

Claims

1. A multi-park integrated energy system energy scheduling method considering thermal energy quality, characterized in that: The following steps are involved: (1) According to the thermal energy quality of the equipment, the equipment is divided into high-energy consumption equipment and low-energy consumption equipment. High-energy consumption equipment forms a high-energy consumption park, and low-energy consumption equipment forms a low-energy consumption park. The output model of the equipment and the waste heat interaction device model are established; (2) The high-energy consumption park is interconnected with the low-energy consumption park through the waste heat interaction device, and the heat energy benefit balance between the high-energy consumption park and the low-energy consumption park is established based on the output model of the equipment and the waste heat interaction device model; (3) Based on the output model of high-energy consumption equipment, the total operating cost of the park's comprehensive energy system is calculated, and a high-energy consumption park model is constructed; based on the output model of low-energy consumption equipment, the total operating cost of the park's comprehensive energy system is calculated, and a low-energy consumption park model is constructed; (4) Establishing a profit model for integrated energy operators based on the revenue from electricity purchase and sales between integrated energy operators and upper-level power grids, and the revenue from electricity purchase and sales between integrated energy operators and integrated energy system clusters in the park; the integrated energy system clusters in the park include high-energy consumption parks and low-energy consumption parks; (5) Based on the high-energy consumption park model, the low-energy consumption park model, the integrated energy operator interest model, and the energy transaction between the high-energy consumption park and the low-energy consumption park, a master-slave game model between the integrated energy operator and the park integrated energy system cluster and a cooperative game model between the members of the park integrated energy system cluster are established, with the maximization of the interests of the integrated energy operator and the minimization of the costs of the members of the park integrated energy system cluster as the objective functions respectively; (6) The binary search method is used to solve the master-slave game model between the integrated energy operator and the park integrated energy system cluster, and the ADMM algorithm is used to solve the cooperative game model between the members of the park integrated energy system cluster, and the optimal energy scheduling method for the multi-park integrated energy system is obtained.

2. The energy dispatching method for a multi-park integrated energy system considering thermal energy quality according to claim 1 is characterized in that: The high energy consumption equipment includes cogeneration equipment. When establishing the output model of the cogeneration equipment, an organic Rankine cycle is introduced to convert the excess waste heat into electrical energy, and an improved cogeneration model is established: in, is the thermal power output of the gas turbine in time t, and are the thermal powers input to the waste heat boiler and the organic Rankine cycle during time t, and are the output thermal power of the organic Rankine cycle and the waste heat boiler in time t, δ ORC,i is the conversion efficiency of the organic Rankine cycle, δ WHB,i is the heat loss of the waste heat boiler, and are the upper and lower limits of the organic Rankine cycle input power within time t, and are the upper and lower limits of the ramp rate of the organic Rankine cycle in time t; The final improved thermal and electrical output power of cogeneration is: in, is the electrical output power of the improved CHP in time t, and are the electrical power outputs of the organic Rankine cycle and the micro gas turbine in time t, is the thermal output power of the improved CHP in time t, is the heat output power of the waste heat boiler during time t.

3. The energy dispatching method for a multi-park integrated energy system considering thermal energy quality according to claim 2 is characterized in that: The low-energy consumption equipment includes heat pumps, which include compression heat pumps MHP, heat-releasing absorption heat pumps AHP, temperature-raising absorption heat converters AHT, high-temperature heat pumps HHP, and gas boilers GB; The model of the compression heat pump MHP is: in, is the electrical power input by the MHP in time t, is the low-grade thermal energy input by MHP in time t, μ MHP,i is the MHP efficiency conversion coefficient, when α MHP,t =0.7, β MHP,t =0.8, are the input temperature of the condenser in time t and the output temperature of the evaporator in time t, is the coefficient of performance of the MHP under actual operating conditions; The model of the heat release type absorption heat pump AHP is: in, is the electrical power input by AHP in time t, is the low-grade heat energy input by AHP in time t, μ AHP,i is the AHP efficiency conversion coefficient, is the performance coefficient of AHP under actual conditions, is the performance coefficient under the ideal state of AHP, is the generator temperature during time t, is the evaporator temperature during time t, is the condenser temperature during time t; The model of the temperature raising absorption heat converter AHT is: in, is the low-grade thermal energy input by AHT during time t, is the operating coefficient of AHT in actual state, μ AHT,i is the AHT efficiency conversion coefficient, is the performance coefficient of AHT under ideal conditions, The temperature of the generator during time t, is the temperature of the evaporator during time t, is the temperature of the condenser during time t, is the temperature of the absorption tower during time t; The model of the high temperature heat pump HHP is: in, is the electrical power input by HHP in time t, is the low-grade heat energy input by HHP in time t, is the performance coefficient of HHP under actual operating conditions, μ HHP,i is the efficiency conversion coefficient of HHP, is the temperature of the evaporator during time t, is the temperature of the condenser during time t; The model of the gas boiler GB is: in, is the natural gas consumption of GB in time t, is the thermal output power of GB in time t, δ GB,i is the energy conversion efficiency of GB, are the upper and lower limits of GB’s natural gas consumption in time t.

4. The energy dispatching method for a multi-park integrated energy system considering thermal energy quality according to claim 3 is characterized in that: The model of the waste heat interaction device is: in, is the thermal energy exchange power between low-energy consumption parks, and The heat output power of the heat recovery device HR-WHRD and the heat exchanger HE-WHRD in time t, and The heat energy input power of the heat recovery device HR-WHRD and the heat exchanger HE-WHRD in time t, is the high-quality thermal energy obtained by the low-energy consumption park from the high-energy consumption park during time t, δ HR,i and δ HE,i are the energy conversion efficiencies of the heat recovery device HR-WHRD and the heat exchanger HE-WHRD, and It is the upper and lower limits of the heat energy input power of the heat exchanger HE-WHRD within time t.

5. The energy dispatching method for a multi-park integrated energy system considering thermal energy quality according to claim 4 is characterized in that: The specific aspects of establishing a balance between the heat energy benefits of high-energy consumption parks and low-energy consumption parks are as follows: in, It represents the thermal output power of the improved cogeneration within time t, that is, the high-quality thermal energy generated by the high-energy consumption park within time t. Indicates the high-quality thermal energy demand of high-energy consumption parks, It is expressed as the heat energy flowing from the high-energy consumption park to the low-energy consumption park within time t.

6. The energy dispatching method for a multi-park integrated energy system considering thermal energy quality according to claim 5 is characterized in that: The objective function in the high energy consumption park model is: in, is the total operating cost of the high energy consumption park, C g,ele,i,t is the cost of purchasing electricity, C g,gas,i,t is the cost of purchasing natural gas, C g,equ,i,t is the component operation and maintenance cost, are the prices of electricity and natural gas purchased by the high energy consumption park in time t, is the electric power purchased by the high energy consumption park in time t, is the natural gas purchased by the high energy consumption park within time t; The objective function of the low energy consumption park model is: in, is the total operating cost of the low-energy park, C d,ele,i,t is the cost of purchasing electricity for the low-energy consumption park, C d,heat,i,t is the cost of low-energy consumption parks purchasing heat from high-energy consumption parks, C d,gas,i,t is the cost of purchasing natural gas for the low-energy consumption park, C d,equ,i,t is the operation and maintenance cost of the low-energy park, are the prices of electricity and natural gas purchased by the low-energy consumption park in time t, is the electric power purchased by the low energy consumption park in time t, is the natural gas purchased by the low-energy consumption park within time t, The price at which the low-energy consumption park purchases heat energy from the high-energy consumption park within time t, It is the thermal power purchased by the low-energy consumption park from the high-energy consumption park within time t.

7. The energy dispatching method for a multi-park integrated energy system considering thermal energy quality according to claim 6 is characterized in that: The comprehensive energy operator benefit model is: in, is the revenue of the integrated energy operator in time t, and are the on-grid electricity price and the grid electricity price within time t, and are the electricity sold to and purchased from the upper power grid within time t, and is the electricity purchase and sales price set by the integrated energy operator to the high and low energy consumption parks at time t, and They are the electricity sales and electricity purchases of high and low energy consumption parks within time t respectively.

8. The energy dispatching method for a multi-park integrated energy system considering thermal energy quality according to claim 7 is characterized in that: The master-slave game model between the integrated energy operator and the park integrated energy system cluster is: in, is the interaction cost between the integrated energy system cluster and the integrated energy operator in time t, C grid,i,t is the electricity purchase cost of the park integrated energy system cluster within time t, C fuel,i,t is the fuel cost consumed in the park integrated energy system cluster within time t, C trade,i,t is the energy sharing cost of the park integrated energy system cluster within time t, C gd,equ,i,t is the equipment maintenance cost of the integrated energy system cluster in the park within time t, including the operation and maintenance cost of equipment in high-energy consumption parks, the operation and maintenance cost of equipment in low-energy consumption parks, and the operation and maintenance cost of waste heat interaction devices. is the total natural gas demand of the park's integrated energy system cluster in period t, is the price paid per unit of electricity when a high-energy consumption park interacts with a low-energy consumption park. is the price paid per unit of thermal energy when a high-energy consumption park interacts with a low-energy consumption park, is the energy transaction volume between the high energy consumption park and the low energy consumption park in time t, is the heat energy trading volume between the high-energy consumption park and the low-energy consumption park in time t.

9. The energy dispatching method for a multi-park integrated energy system considering thermal energy quality according to claim 8 is characterized in that: The cooperative game model among the members of the park integrated energy system cluster is: Among them, U i The benefits of participating in the negotiation for the park's integrated energy system cluster, The benefits of participating in the pre-negotiation negotiations for the integrated energy system cluster of the park; Maximizing cluster benefits: Maximizing Energy Trading Profits: Among them, δ i Represents the optimal solution for payment of electricity and heat transactions, and C0 represents the benchmark cost.

10. The multi-park integrated energy system energy scheduling method considering thermal energy quality according to claim 9, characterized in that: The dichotomy method is used to solve the master-slave game between integrated energy operators and park integrated energy system clusters: set up is the energy price at time t in the nth iteration, if is the lower limit at this time, then when Add constraints: like Add constraints: Each iteration reduces the iteration interval, and each iteration determines whether the result meets the convergence condition. If convergence occurs, the iteration ends. The convergence conditions are: in, and are the electricity purchase and sales prices set by the integrated energy operator to the park integrated energy system cluster at time t in the nth iteration, and δ is the convergence criterion; The ADMM algorithm is used to solve the cooperative game model between cluster members of the park's integrated energy system. The specific solution steps are as follows: ① Initialize the number of iterations n = 1, the penalty factor ρ e,0 , h,0 , convergence criterion ε p , ε d , the Lagrange multiplier Initialize high and low energy consumption park decision variables ② Obtain the transaction heat expected by the members of the park's integrated energy system cluster and transaction volume Solving it, we can get the expected transaction heat of the park: and transaction volume Update the penalty factor ρ e,n+1 , h,n+1 ; ③ Determine whether the original residual and the dual residual meet the convergence criteria; if the conditions are met, the iteration ends, and the decision variables of the high and low energy consumption parks are The lowest adjustable equipment adjustment plan to meet the operating costs of high and low energy consumption parks; if the conditions are not met, proceed to step ④; Among them, r n+1 ,d n+1 are the primal residual and the dual residual respectively; ④ Set the number of iterations n = n + 1, update the decision variables of high and low energy consumption parks with penalty factors, and the iterative update formula of the decision variables of high and low energy consumption parks is: Update Lagrange multipliers The iterative update formula of the Lagrange multiplier is: in, is the decision variable of high and low energy consumption parks in the nth iteration, ρ e,n , h,n are the penalty factors for electricity and heat at the nth iteration, are the Lagrange multipliers of the nth iteration electric power and thermal power, respectively, is the auxiliary variable introduced; Return to step ② and continue.

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