An optimal scheduling method for coal-fired unit coupled with compressed air energy storage system

Abstract

The application discloses a kind of optimization scheduling methods of coal-fired unit coupling compressed air energy storage system, make up the problem of lack of coal-fired unit and compressed air energy storage coupling system operation management method in prior art, including the mathematical modeling of operating income to all working conditions of coupling system;According to the relationship between power grid scheduling demand and coal-fired unit rated power supply, the relationship between compressed air energy storage power and rated capacity, determine the selectable operating mode of coupling system, obtain the initial screening working condition set;With satisfying power grid scheduling demand as the first principle, the maximum of coupling system unit power supply income as the second principle, screening is carried out in initial screening working condition set, obtain final working condition;Get the corresponding coupling system income, coal-fired unit load rate and compressed air energy storage charge / discharge load rate when unit power supply income is maximum under final working condition, realize coupling system operation scheduling.Coupling system income maximization is realized, and the reasonable operation of each equipment of coupling system is guaranteed.

Description

Technical Field

[0001] This invention relates to the field of energy storage system optimization scheduling technology, and in particular to an optimization scheduling method for a coal-fired unit coupled with compressed air energy storage system. Background Technology

[0002] With the continuous increase in the installed capacity of renewable energy, the pressure on traditional thermal power, as the main peak-shaving power source of the power grid, is increasing. Long-term low-load operation not only increases fuel consumption and affects the economic efficiency of operation, but also damages thermal power equipment and affects the overall life of the unit.

[0003] Compressed-air energy storage (CAES) is a technology that uses the compression and expansion of air to store and release energy. It works by using electricity to compress and store air during periods of low electricity demand, and then releasing the high-pressure air to drive a turbine to generate electricity during periods of peak demand. As a large-scale energy storage technology with large storage capacity, long storage period, environmental friendliness, flexibility, and high efficiency, CAES, when coupled with traditional coal-fired power units, can significantly improve the deep peak-shaving capacity of traditional coal-fired units, reduce carbon emissions per unit of electricity generated, and improve the economic efficiency of unit operation.

[0004] Existing research on the optimal scheduling of compressed air energy storage (CSP) systems mostly considers CSP's independent participation in power system optimal scheduling. A few studies involve optimizing the thermodynamic performance and techno-economic aspects of coupled power plants and CSP systems, but few address the operational scheduling modes of such systems, lacking direct guidance for their operation and management. For example, the Chinese Patent Office published patent CN113067353A on May 28, 2021: "A System Optimization Scheduling Method Considering CSP Power Plant Coupled with AA-CAES Power Plant," which can rationally select energy storage types and scientifically configure energy storage capacity based on economic benefits, significantly reducing power generation costs. However, this study focuses more on the thermodynamic performance and techno-economic aspects of the coupled system to configure the optimal energy storage capacity, but it doesn't clarify how the coupled system operates and is scheduled, nor does it understand the load factors of coal-fired power plants and the charging and discharging load factors of compressed air energy storage. Summary of the Invention

[0005] The purpose of this invention is to address the lack of guidance methods in the existing technology for the operation and management of coal-fired power unit coupled with compressed air energy storage systems, which fails to reasonably determine the operating conditions of each device in the coupled system to maximize operational benefits. This invention provides an optimized scheduling method for coal-fired power unit coupled with compressed air energy storage systems. Under the premise of prioritizing grid dispatch needs, and based on user-defined boundary conditions such as coal-fired power unit, compressed air energy storage installed capacity, performance parameters, and electricity prices, this method determines the load factor of the coal-fired power unit and the charge / discharge load factor of the compressed air energy storage system to maximize unit power supply revenue, thus guiding the operation and management of the coal-fired power unit coupled with compressed air energy storage systems.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: An optimized scheduling method for a coal-fired power unit coupled with a compressed air energy storage system includes the following steps: S1: Mathematical modeling of the operational benefits of the coal-fired power unit coupled with the compressed air energy storage system under all operating conditions; S2: Based on the relationship between the grid dispatch demand N and the rated power z of the coal-fired unit, and the relationship between the compressed air energy storage capacity r and the rated capacity R, determine the selectable operating modes of the coupled system and obtain the set of initial screening conditions. S3: The first principle is to meet the grid dispatch demand N, and the second principle is to maximize the unit power supply revenue Q of the coupled system. The final operating condition is obtained by screening from the initial set of operating conditions. S4: Obtain the coupled system revenue W, coal-fired unit load rate δ1, and compressed air energy storage charging / discharging load rate (δ3 or δ2) corresponding to the maximum unit power supply revenue Q under the final operating condition, and realize the operation scheduling of the coupled system.

[0007] Preferably, S2 includes: the relationship between the grid dispatch demand N and the rated power supply z of the coal-fired unit includes: the grid dispatch demand N is greater than or equal to the rated power supply z of the coal-fired unit; the grid dispatch demand N is greater than or equal to 30% of the rated power supply z of the coal-fired unit and less than the rated power supply z of the coal-fired unit; the grid dispatch demand N is less than 30% of the rated power supply z of the coal-fired unit; the relationship between the compressed air energy storage capacity r and the rated capacity R includes: the compressed air energy storage capacity r is equal to the rated capacity R; the compressed air energy storage capacity r is 0; the compressed air energy storage capacity r is less than the rated capacity R and greater than 0; the compressed air energy storage cannot be charged or discharged; combining the relationship between the grid dispatch demand N and the rated power supply z of the coal-fired unit and the relationship between the compressed air energy storage capacity r and the rated capacity R yields a set of initial screening conditions under 12 operating states.

[0008] Preferably, S3 includes: the screening principle for screening in the initial screening condition set is: (1) Prioritize the operating conditions that meet the grid dispatching requirements N; (2) If there is a working condition that satisfies (1), select the working condition corresponding to the maximum unit power supply revenue Q of the coupled system as the operating condition; if there is no working condition that satisfies (1), select the working condition corresponding to the maximum unit power supply revenue Q of the coupled system as the operating condition among the working conditions that do not meet the grid dispatch requirements.

[0009] As a preferred option, it is determined whether to switch operating conditions based on whether the compressed air energy storage is fully discharged or fully charged under the current operating conditions.

[0010] As a preferred option, if the coal-fired unit is supplied with its own power, then there is no need to switch operating conditions.

[0011] Preferably, if there is a change in operating conditions within the operating time t, and the current operating condition is that the grid dispatch demand N is greater than or equal to 30% of the rated power z of the coal-fired unit but less than the rated power z of the coal-fired unit, or the grid dispatch demand N is less than 30% of the rated power z of the coal-fired unit and a joint power supply mode of coal-fired unit and compressed air energy storage is adopted, then this operating condition will last for t hours. j After a certain period of time, switch to the initial screening condition set where the compressed air energy storage capacity r equals the rated capacity R; under other conditions, continue operating under the current condition for t. j After a certain period of time, the system switches to the initial screening condition set where the compressed air energy storage capacity r is 0; the screening principle of the initial screening condition remains unchanged after the condition switch.

[0012] As a preferred approach, the initial energy quantity r0 of compressed air energy storage and the charging energy quantity and charging cost obtained under different load rates of coal-fired units are classified into tiers. The energy quantity and cost of the tiers are uniformly measured by the discharge energy quantity r that can be released by compressed air energy storage and the unit discharge cost u, and are arranged from low to high according to the unit discharge cost u. During the discharge process of compressed air energy storage, the energy quantity with the lower unit discharge cost u is released first, until the grid dispatch command is completed or all tiers of energy quantity are released.

[0013] Preferably, the final operating conditions include: whether the power supply mode of the coupled system and the power supply under the current power supply mode meet the grid dispatch requirements N, the load rate of the coal-fired unit δ1, the charge / discharge load rate of the compressed air energy storage (δ3 or δ2), and the revenue of the coupled system W.

[0014] Preferably, the power supply modes of the coupling system include: joint power supply of coal-fired power unit and compressed air energy storage, power supply of coal-fired power unit alone, and power supply of compressed air energy storage alone.

[0015] As a preferred approach, when there are multiple scheduling instructions or a single scheduling instruction involves multiple operating conditions, an optimal combination of operating conditions is formed, and the operating conditions, coupled system benefits, and other relevant information are described in different time periods.

[0016] Therefore, the present invention has the following beneficial effects: taking the grid dispatch demand, coal-fired power units, compressed air energy storage capacity, performance parameters and electricity prices as boundary conditions as input objects, it constructs an optimized dispatch mode of "power source + energy storage" under a new power system. It can optimize the operation mode of the coal-fired power unit and compressed air energy storage coupling system for different grid dispatch demand commands, and maximize the operating benefits of the coupling system. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating the overall steps of the optimized scheduling method for a coal-fired unit coupled with a compressed air energy storage system in an embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of the working condition switching process in an embodiment of the present invention.

[0019] Figure 3 This is a schematic diagram of the fitting function relationship between the actual power generation of the coal-fired unit and the standard coal consumption rate in Embodiment 2 of the present invention. Detailed Implementation

[0020] The technical solution and technical effects of the present invention will be described below with reference to the accompanying drawings and specific embodiments. The following embodiments are explanations of the present invention, but the present invention is not limited to the following embodiments.

[0021] Example 1: This embodiment provides an optimized scheduling method for a coal-fired power unit coupled with a compressed air energy storage system, such as... Figure 1 As shown, the operation process is as follows: Step 1, mathematical modeling of the operating benefits of all operating conditions of the coal-fired unit and compressed air energy storage coupling system; Step 2, based on the relationship between the grid dispatch demand N and the rated power supply z of the coal-fired unit, and the relationship between the compressed air energy storage capacity r and the rated capacity R, determining the selectable operating modes of the coupling system to obtain a preliminary set of operating conditions; Step 3, with satisfying the grid dispatch demand N as the first principle and maximizing the unit power supply benefit Q of the coupling system as the second principle, filtering from the preliminary set of operating conditions to obtain the final operating conditions; Step 4, obtaining the coupling system benefit W, coal-fired unit load rate δ1, and compressed air energy storage charging / discharging load rate (δ3 or δ2) corresponding to the maximum unit power supply benefit Q under the final operating conditions, and realizing the operation scheduling of the coupling system.

[0022] The following is a further explanation of the specific steps involved: Step 1: Perform mathematical modeling of the operational benefits of the coal-fired power unit and compressed air energy storage coupling system under all operating conditions.

[0023] This embodiment includes 14 operating conditions: operating condition 1 (1-1-1), operating condition 2 (1-1-2), operating condition 3 (1-2), operating condition 4 (1-3-1), operating condition 5 (1-3-2), operating condition 6 (2-1), operating condition 7 (2-2), operating condition 8 (2-3-1), operating condition 9 (2-3-2), operating condition 10 (3-1-1), operating condition 11 (3-1-2), operating condition 12 (3-2), operating condition 13 (3-3-1), and operating condition 14 (3-3-2). The coupled system benefit W and the unit power supply benefit Q for these 14 operating conditions are calculated below.

[0024] Specifically: First operating condition (1-1-1): This operating condition requires that the compressed air energy storage can be discharged, and the grid dispatch demand N is greater than or equal to the rated power supply z of the coal-fired unit and less than or equal to the sum of the rated power supply z of the coal-fired unit and the rated discharge power c of the compressed air energy storage.

[0025] This operating condition adopts a power supply mode that combines coal-fired power units and compressed air energy storage, and the output of the coupled system meets the grid dispatching requirements N.

[0026] Under this operating condition, the revenue W of the coupled system equals the revenue from the coal-fired power generation unit minus the corresponding power generation cost (variable cost) plus the revenue from compressed air energy storage discharge minus the corresponding charging cost; the unit power supply revenue Q of the coupled system equals the ratio of the coupled system revenue W to the power supply S, where the power supply S is equal to the operating time t under this condition. j The product of the power grid dispatch demand N.

[0027] Second operating condition (1-1-2): This operating condition requires that the compressed air energy storage can be discharged, and the grid dispatch demand N is greater than the sum of the rated power supply z of the coal-fired unit and the rated discharge power c of the compressed air energy storage.

[0028] This operating condition adopts a power supply mode jointly powered by coal-fired units and compressed air energy storage, and the output of the coupled system is lower than the grid dispatch demand N.

[0029] Under this operating condition, the revenue W of the coupled system equals the revenue from the coal-fired power generation unit minus the corresponding power generation cost (variable cost) plus the revenue from compressed air energy storage discharge minus the corresponding charging cost; the unit power supply revenue Q of the coupled system equals the ratio of the coupled system revenue W to the power supply S, where the power supply S is equal to the operating time t under this condition. j The product of the maximum power supply of the coupled system (the sum of the rated power generation of the coal-fired unit a and the rated discharge power of the compressed air energy storage c).

[0030] Third operating condition (1-2): This operating condition requires that the grid dispatch demand N be greater than or equal to the rated power supply power z of the coal-fired unit.

[0031] In this operating condition, the coal-fired unit is supplied with power independently, and the output of the coupled system is lower than the grid dispatch demand N.

[0032] Under this operating condition, the revenue W of the coupled system equals the revenue from power generation by the coal-fired unit minus the corresponding power generation cost (variable cost); the unit power supply revenue Q of the coupled system equals the ratio of the coupled system revenue W to the power supply S. At this point, the power supply S is equal to the operating time t under this condition. j The product of the rated power output 'a' of the coal-fired unit.

[0033] Fourth operating condition (1-3-1): This operating condition requires that the compressed air energy storage can be discharged, and the grid dispatch demand N is greater than or equal to the rated power supply z of the coal-fired unit and less than or equal to the rated discharge power c of the compressed air energy storage.

[0034] In this operating condition, a compressed air energy storage independent power supply mode is adopted, and the output of the coupling system meets the grid dispatching requirements N.

[0035] Under this operating condition, the revenue W of the coupled system equals the revenue from compressed air energy storage discharge minus the corresponding charging cost; the unit power supply revenue Q of the coupled system equals the ratio of the coupled system revenue W to the power supply S, where the power supply S is equal to the operating time t under this condition. j The product of the power grid dispatch demand N.

[0036] Fifth operating condition (1-3-2): This operating condition requires that the compressed air energy storage can be discharged, and the grid dispatch demand N is greater than or equal to the rated power supply z of the coal-fired unit and greater than the rated discharge power c of the compressed air energy storage.

[0037] In this operating condition, compressed air energy storage is used as the stand-alone power supply mode, and the output of the coupled system is lower than the grid dispatch demand N.

[0038] Under this operating condition, the revenue W of the coupled system equals the revenue from compressed air energy storage and discharge minus the corresponding electricity cost; the unit power supply revenue Q of the coupled system equals the ratio of the coupled system revenue W to the power supply S. At this point, the power supply S is equal to the operating time t under this condition. j The product of the rated discharge power c of the compressed air energy storage.

[0039] Sixth operating condition (2-1): This operating condition requires that the compressed air energy storage is rechargeable, and the grid dispatch demand N is greater than or equal to 30% of the rated power supply z of the coal-fired unit and less than the rated power supply z of the coal-fired unit.

[0040] This operating condition adopts a power supply mode jointly powered by coal-fired units and compressed air energy storage. The excess output of the coal-fired units charges the compressed air energy storage, and the output of the coupled system meets the grid dispatching requirements N.

[0041] Under this operating condition, the coupled system revenue W equals the revenue generated by the coal-fired power unit to meet the grid dispatch demand N minus the generation cost (variable cost) of the coal-fired power unit to meet the grid dispatch demand N plus the deep peak-shaving subsidy for the coal-fired power unit (if any). When the ratio of the grid dispatch demand N to the rated power supply of the coal-fired power unit is less than the base load rate δ0 for the deep peak-shaving subsidy, there is a deep peak-shaving subsidy; otherwise, there is none. The unit power supply revenue Q of the coupled system equals the ratio of the coupled system revenue W to the power supply S. In this case, the power supply S is equal to the operating time t under this condition. j The product of the power grid dispatch demand N.

[0042] Under this operating condition, the unit discharge cost u of the compressed air energy storage charging capacity is... i It equals the ratio of the power generation cost of the coal-fired unit corresponding to the energy stored in compressed air to the amount of electricity that can be discharged afterward.

[0043] Seventh operating condition (2-2): This operating condition requires that the grid dispatch demand N is greater than or equal to 30% of the rated power supply z of the coal-fired unit and less than the rated power supply z of the coal-fired unit.

[0044] In this operating condition, the coal-fired unit is supplied with power independently, and the output of the coupling system meets the grid dispatching requirements N.

[0045] Under this operating condition, the coupled system revenue W equals the coal-fired unit's power generation revenue minus the corresponding power generation cost (variable cost) plus the coal-fired unit's deep peak-shaving subsidy (if any). When the coal-fired unit's load rate δ1 is less than the coal-fired unit's deep peak-shaving subsidy benchmark load rate δ0, there is a deep peak-shaving subsidy; otherwise, there is none. The coupled system's unit power supply revenue Q equals the ratio of the coupled system revenue W to the power supply volume S. At this point, the power supply volume S equals the operating time t under this condition. j The product of the power grid dispatch demand N.

[0046] Eighth operating condition (2-3-1): This operating condition requires that the compressed air energy storage can be discharged, and the grid dispatch demand N is greater than or equal to 30% of the rated power supply z of the coal-fired unit and less than or equal to the rated power supply z of the coal-fired unit and less than or equal to the rated discharge power c of the compressed air energy storage.

[0047] In this operating condition, a compressed air energy storage independent power supply mode is adopted, and the output of the coupling system meets the grid dispatching requirements N.

[0048] Under this operating condition, the revenue W of the coupled system equals the revenue from compressed air energy storage discharge minus the corresponding charging cost plus the deep peak-shaving subsidy for coal-fired power units (if applicable). When the ratio of grid dispatch demand N to the rated power supply z of the coal-fired power units is less than the base load rate δ0 for the deep peak-shaving subsidy, there is a deep peak-shaving subsidy; otherwise, there is none. The unit power supply revenue Q of the coupled system equals the ratio of the coupled system revenue W to the power supply S. At this time, the power supply S is equal to the operating time t under this condition.j The product of the power grid dispatch demand N.

[0049] Ninth Operating Condition (2-3-2): This operating condition requires that the compressed air energy storage can be discharged, and the grid dispatch demand N is greater than or equal to 30% of the rated power supply z of the coal-fired unit and less than the rated power supply z of the coal-fired unit and greater than the rated discharge power c of the compressed air energy storage.

[0050] In this operating condition, compressed air energy storage is used as the stand-alone power supply mode, and the output of the coupled system is lower than the grid dispatch demand N.

[0051] Under this operating condition, the revenue W of the coupled system equals the revenue from compressed air energy storage discharge minus the corresponding charging cost plus the deep peak-shaving subsidy for coal-fired power units (if applicable). When the ratio of grid dispatch demand N to the rated power supply z of the coal-fired power units is less than the base load rate δ0 for the deep peak-shaving subsidy, there is a deep peak-shaving subsidy; otherwise, there is none. The unit power supply revenue Q of the coupled system equals the ratio of the coupled system revenue W to the power supply S. At this time, the power supply S is equal to the operating time t under this condition. j The product of the rated discharge power c of the compressed air energy storage.

[0052] The tenth operating condition (3-1-1): This operating condition requires that the compressed air energy storage be rechargeable, the grid dispatch demand N be less than 30% of the rated power z of the coal-fired unit and less than the minimum output of the coupled system.

[0053] This operating condition adopts a power supply mode jointly powered by coal-fired units and compressed air energy storage. The excess output of the coal-fired units charges the compressed air energy storage, and the output of the coupled system is higher than the grid dispatch demand N.

[0054] Under this operating condition, the coupled system revenue W equals the revenue from the coal-fired power unit meeting the grid dispatch demand N minus the power generation cost of the coal-fired power unit excluding charging the compressed air energy storage, plus the deep peak-shaving subsidy for the coal-fired power unit (if any). When the ratio of the actual power supply of the coupled system to the rated power supply z of the coal-fired power unit is less than the base load rate δ0 for the deep peak-shaving subsidy, there is a deep peak-shaving subsidy; otherwise, there is none. The unit power supply revenue Q of the coupled system equals the ratio of the coupled system revenue W to the power supply S. In this case, the power supply S is equal to the operating time t under this condition. j The product of the power grid dispatch demand N.

[0055] Under this operating condition, the unit discharge cost u of the compressed air energy storage charging capacity is... i It equals the ratio of the power generation cost of the coal-fired unit corresponding to the energy stored in compressed air to the amount of electricity that can be discharged afterward.

[0056] Eleventh Operating Condition (3-1-2): This operating condition requires that the compressed air energy storage be rechargeable, the grid dispatch demand N be less than 30% of the rated power z of the coal-fired unit and greater than or equal to the minimum output of the coupled system.

[0057] This operating condition adopts a power supply mode jointly powered by coal-fired units and compressed air energy storage. The excess output of the coal-fired units charges the compressed air energy storage, and the output of the coupled system meets the grid dispatching requirements N.

[0058] Under this operating condition, the coupled system revenue W equals the revenue generated by the coal-fired power unit to meet the grid dispatch demand N minus the generation cost (variable cost) of the coal-fired power unit to meet the grid dispatch demand N plus the deep peak-shaving subsidy for the coal-fired power unit (if any). When the ratio of the grid dispatch demand N to the rated power supply z of the coal-fired power unit is less than the base load rate δ0 for the deep peak-shaving subsidy, there is a deep peak-shaving subsidy; otherwise, there is none. The unit power supply revenue Q of the coupled system equals the ratio of the coupled system revenue W to the power supply S. At this time, the power supply S is equal to the operating time t under this condition. j The product of the power grid dispatch demand N.

[0059] Under this operating condition, the unit discharge cost u of the compressed air energy storage charging capacity is... i It equals the ratio of the power generation cost of the coal-fired unit corresponding to the energy stored in compressed air to the amount of electricity that can be discharged afterward.

[0060] Operating Condition 12 (3-2): This operating condition requires that the rated power supply power z of the coal-fired power unit be less than 30% of the grid dispatch demand N.

[0061] In this operating condition, the coal-fired unit is supplied with power independently, and the output of the coupled system is higher than the grid dispatch demand N.

[0062] Under this operating condition, the coupled system revenue W equals the revenue from the coal-fired power unit meeting the grid dispatch demand N minus the actual power generation cost (variable cost) of the coal-fired power unit plus the deep peak-shaving subsidy for the coal-fired power unit (if any). When the load factor δ1 of the coal-fired power unit is less than the benchmark load factor δ0 for the deep peak-shaving subsidy, there is a deep peak-shaving subsidy; otherwise, there is none. The unit power supply revenue Q of the coupled system equals the ratio of the coupled system revenue W to the power supply S. In this case, the power supply S is equal to the operating time t under this condition. j The product of the power grid dispatch demand N.

[0063] Operating condition 13 (3-3-1): This operating condition requires that the compressed air energy storage can be discharged, and the grid dispatch demand N is less than 30% of the rated power supply z of the coal-fired unit and less than or equal to the rated discharge power c of the compressed air energy storage.

[0064] In this operating condition, a compressed air energy storage independent power supply mode is adopted, and the output of the coupling system meets the grid dispatching requirements N.

[0065] Under this operating condition, the revenue W of the coupled system equals the revenue from compressed air energy storage discharge minus the corresponding charging cost plus the deep peak-shaving subsidy for coal-fired power units (if applicable). When the ratio of grid dispatch demand N to the rated power supply z of the coal-fired power units is less than the base load rate δ0 for the deep peak-shaving subsidy, there is a deep peak-shaving subsidy; otherwise, there is none. The unit power supply revenue Q of the coupled system equals the ratio of the coupled system revenue W to the power supply S. At this time, the power supply S is equal to the operating time t under this condition. j The product of the power grid dispatch demand N.

[0066] Operating Condition 14 (3-3-2): This operating condition requires that the compressed air energy storage can be discharged, and the grid dispatch demand N is less than 30% of the rated power supply z of the coal-fired unit and greater than the rated discharge power c of the compressed air energy storage.

[0067] In this operating condition, compressed air energy storage is used as the stand-alone power supply mode, and the output of the coupled system is lower than the grid dispatch demand N.

[0068] Under this operating condition, the revenue W of the coupled system equals the revenue from compressed air energy storage discharge minus the corresponding charging cost plus the deep peak-shaving subsidy for coal-fired power units (if applicable). When the ratio of grid dispatch demand N to the rated power supply z of the coal-fired power units is less than the base load rate δ0 for the deep peak-shaving subsidy, there is a deep peak-shaving subsidy; otherwise, there is none. The unit power supply revenue Q of the coupled system equals the ratio of the coupled system revenue W to the power supply S. At this time, the power supply S is equal to the operating time t under this condition. j The product of the rated discharge power c of the compressed air energy storage.

[0069] Step 2: Based on the relationship between the grid dispatch demand N and the rated power z of the coal-fired unit, and the relationship between the compressed air energy storage capacity r and the rated capacity R, determine the selectable operating modes of the coupled system and obtain the initial screening operating condition set.

[0070] The relationship between grid dispatch demand N and the rated power supply z of coal-fired units includes: grid dispatch demand N is greater than or equal to the rated power supply z of coal-fired units; grid demand is greater than or equal to 30% of the rated power supply z of coal-fired units and less than the rated power supply z of coal-fired units; grid dispatch demand N is less than 30% of the rated power supply z of coal-fired units. The relationship between the compressed air energy storage capacity r and the rated capacity R includes: compressed air energy storage capacity r is equal to the rated capacity R; compressed air energy storage capacity is 0; compressed air energy storage capacity r is less than the rated capacity R and greater than 0; compressed air energy storage cannot be charged or discharged. Combining the relationship between grid dispatch demand N and the rated power supply z of coal-fired units with the relationship between compressed air energy storage capacity r and the rated capacity R yields a set of initial screening conditions under 12 operating states.

[0071] Specifically: When the grid dispatch demand N is greater than or equal to the rated power z of the coal-fired power unit: if the compressed air energy storage capacity r is equal to the rated capacity R, then it enters the first preliminary screening condition set; if the compressed air energy storage capacity is 0, then it enters the second preliminary screening condition set; if the compressed air energy storage capacity r is less than the rated capacity R but greater than 0, then it enters the third preliminary screening condition set; if the compressed air energy storage cannot be charged or discharged, then it enters the fourth preliminary screening condition set. When the grid dispatch demand N is greater than or equal to 30% of the rated power z of the coal-fired power unit but less than the rated power z of the coal-fired power unit: if the compressed air energy storage capacity r is equal to the rated capacity R, then it enters the fifth preliminary screening condition set; if the compressed air energy storage capacity is 0, then it enters the sixth preliminary screening condition set; if the compressed air energy storage capacity r is less than the rated capacity R but greater than 0, then it enters the seventh preliminary screening condition set; if the compressed air energy storage cannot be charged or discharged, then it enters the eighth preliminary screening condition set. When the grid dispatch demand N is less than 30% of the rated power z of the coal-fired power unit: if the compressed air energy storage capacity r is equal to the rated capacity R, then enter the ninth initial screening condition set; if the compressed air energy storage capacity is 0, then enter the tenth initial screening condition set; if the compressed air energy storage capacity r is less than the rated capacity R but greater than 0, then enter the eleventh initial screening condition set; if the compressed air energy storage cannot be charged or discharged, then enter the twelfth initial screening condition set.

[0072] Specifically: (a) The grid dispatch demand N is greater than or equal to the rated power supply z of the coal-fired power unit.

[0073] In this case, the relationship between the energy storage capacity r of compressed air and the rated capacity R can take four forms: 1. The energy stored in compressed air, r, is equal to the rated capacity, R, meaning that compressed air energy storage can only discharge.

[0074] At this point, the 14 operating conditions are screened to obtain the first set of initial operating conditions, including: operating condition 1-1-1, operating condition 1-1-2 (the output of the coupled system under this operating condition is lower than the grid dispatch demand N), operating condition 1-2 (the output of the coupled system under this operating condition is lower than the grid dispatch demand N), operating condition 1-3-1 and operating condition 1-3-2 (the output of the coupled system under this operating condition is lower than the grid dispatch demand N).

[0075] 2. If the energy storage capacity r of compressed air is 0, then compressed air energy storage can only be charged.

[0076] At this point, the 14 operating conditions are screened to obtain the second set of preliminary operating conditions. Under this condition, only the coal-fired unit can be used for power supply. Only one operating condition meets the conditions, namely operating condition 1-2 (the output of the coupled system under this operating condition is lower than the grid dispatch demand N).

[0077] 3. The energy storage capacity r of compressed air is less than the rated capacity R and greater than 0, meaning that compressed air energy storage can both charge and discharge.

[0078] At this point, the 14 operating conditions are screened to obtain the third preliminary set of operating conditions, including: operating condition 1-1-1, operating condition 1-1-2 (the output of the coupled system under this operating condition is lower than the grid dispatch demand N), operating condition 1-2 (the output of the coupled system under this operating condition is lower than the grid dispatch demand N), operating condition 1-3-1 and operating condition 1-3-2 (the output of the coupled system under this operating condition is lower than the grid dispatch demand N).

[0079] 4. Compressed air energy storage cannot be charged or discharged.

[0080] At this point, the 14 operating conditions are screened to obtain the fourth set of initial operating conditions. Under this condition, only the coal-fired unit can be used for power supply. Only one operating condition meets the conditions, namely operating condition 1-2 (the output of the coupled system under this operating condition is lower than the grid dispatch demand N).

[0081] (ii) The grid dispatch demand N is greater than or equal to 30% of the rated power supply z of the coal-fired power units and less than the rated power supply z of the coal-fired power units.

[0082] In this case, there are four forms of relationship between the energy storage capacity r of compressed air and the rated capacity R: 1. The energy storage capacity r of compressed air is equal to the rated capacity R, that is, compressed air energy storage can only be discharged.

[0083] At this point, the 14 operating conditions are screened to obtain the fifth set of initial operating conditions, including: operating conditions 2-2, 2-3-1 and operating conditions 2-3-2 (the output of the coupled system under this operating condition is lower than the grid dispatch demand N).

[0084] 2. If the energy storage capacity r of compressed air is 0, then compressed air energy storage can only be charged.

[0085] At this point, the 14 working conditions are screened to obtain the sixth preliminary set of working conditions, including: working condition 2-1 and working condition 2-2.

[0086] 3. The energy storage capacity r of compressed air is less than the rated capacity R and greater than 0, meaning that compressed air energy storage can both charge and discharge.

[0087] At this point, the 14 operating conditions are screened to obtain the seventh preliminary set of operating conditions, including: operating condition 2-1, operating condition 2-2, operating condition 2-3-1 and operating condition 2-3-2 (the output of the coupled system under this operating condition is lower than the grid dispatch demand N).

[0088] 4. Compressed air energy storage cannot be charged or discharged.

[0089] At this point, the 14 operating conditions are screened to obtain the eighth set of initial operating conditions. Under this condition, only the coal-fired unit can be used for power supply. Only one operating condition meets the conditions, namely operating condition 2-2 (the output of the coupled system under this operating condition is lower than the grid dispatch demand N).

[0090] (iii) The grid dispatch demand N is less than 30% of the rated power supply z of coal-fired units.

[0091] In this case, there are four forms of relationship between the energy storage capacity r of compressed air and the rated capacity R: 1. The energy storage capacity r of compressed air is equal to the rated capacity R, that is, compressed air energy storage can only be discharged.

[0092] At this point, the 14 operating conditions are screened to obtain the ninth preliminary set of operating conditions, including: operating condition 3-2 (the output of the coupled system in this operating condition is higher than the grid dispatch demand N), operating condition 3-3-1 and operating condition 3-3-2 (the output of the coupled system in this operating condition is lower than the grid dispatch demand N).

[0093] 2. If the energy storage capacity r of compressed air is 0, then compressed air energy storage can only be charged.

[0094] At this point, the 14 operating conditions are screened to obtain the tenth preliminary set of operating conditions, including: operating condition 3-1-1 (the output of the coupled system in this operating condition is higher than the grid dispatch demand N), operating condition 3-1-2 and operating condition 3-2 (the output of the coupled system in this operating condition is higher than the grid dispatch demand N).

[0095] 3. The energy storage capacity r of compressed air is less than the rated capacity R and greater than 0, meaning that compressed air energy storage can both charge and discharge.

[0096] At this point, the 14 operating conditions are screened to obtain the eleventh preliminary set of operating conditions, including: operating condition 3-1-1 (the output of the coupled system under this operating condition is higher than the grid dispatch demand N), operating condition 3-1-2, operating condition 3-2 (the output of the coupled system under this operating condition is higher than the grid dispatch demand N), operating condition 3-3-1 and operating condition 3-3-2 (the output of the coupled system under this operating condition is lower than the grid dispatch demand N).

[0097] 4. Compressed air energy storage cannot be charged or discharged.

[0098] At this point, the 14 operating conditions are screened to obtain the twelfth preliminary set of operating conditions. Under this condition, only the coal-fired unit can be used for power supply. Only one operating condition meets the conditions, namely operating condition 3-2 (the output of the coupled system under this operating condition is higher than the grid dispatch demand N).

[0099] Among them, (I), (II), (III) and their subordinate 1, 2, 3, 4, a total of 12 operating states are related by "OR". Subsequently, the operating conditions in the initial screening set of each of the 12 operating states are selected to calculate the coupled system benefit W, the coupled system unit power supply benefit Q and other related parameters.

[0100] The third step is to select the final operating conditions from the initial set of operating conditions, with the first principle being to meet the grid dispatch demand N and the second principle being to maximize the unit power supply revenue Q of the coupled system.

[0101] The operating mode selection principle is as follows: (1) Prioritize the operating conditions that meet the grid dispatching requirements N.

[0102] (2) If there is a working condition that satisfies (1), select the working condition corresponding to the maximum unit power supply revenue Q of the coupled system as the operating condition; if there is no working condition that satisfies (1), select the working condition corresponding to the maximum unit power supply revenue Q of the coupled system as the operating condition among the working conditions that do not meet the grid dispatching requirement N.

[0103] When there are multiple scheduling instructions or a single scheduling instruction involves multiple operating conditions, the present invention can form an optimal combination of operating conditions and describe the operating conditions, coupled system benefits and other relevant parameters under each operating condition in different time periods.

[0104] Step 4: Obtain the coupled system revenue W, coal-fired unit load rate δ1, and compressed air energy storage charging / discharging load rate (δ3 or δ2) corresponding to the maximum unit power supply revenue Q under the final operating conditions, and realize the operation scheduling of the coupled system.

[0105] Determine whether a change in operating mode is needed based on whether the compressed air energy storage is fully discharged or fully charged under the current operating conditions. If the current operating mode is powered solely by a coal-fired unit, then a change in operating mode is not required. Other operating modes are as follows: Figure 2 As shown, if there is a change in operating conditions within the operating time t, and the current operating condition is that the grid dispatch demand N is greater than or equal to 30% of the rated power z of the coal-fired unit and less than the rated power z of the coal-fired unit, or the grid dispatch demand N is less than 30% of the rated power z of the coal-fired unit and a coal-fired unit and compressed air energy storage are used for joint power supply, then this operating condition will last for t. j After a certain period of time, switch to the initial screening condition set where the compressed air energy storage capacity r equals the rated capacity R; under other conditions, continue operating under the current condition for t. j After a certain period of time, switch to the initial screening condition set where the compressed air energy storage capacity is 0.

[0106] The following provides a more detailed explanation of the methods for determining whether a switching operation occurs under each operating condition, and the corresponding coupling system revenue W, coal-fired unit load rate δ1, and compressed air energy storage discharge load rate δ2 or compressed air energy storage charging load rate δ3 when the unit power supply revenue Q of the coupled system is maximized under each operating condition.

[0107] 1. First operating condition (1-1-1) In this working condition, the joint power supply mode of coal-fired unit and compressed air energy storage is adopted. This working condition is constrained by the rated discharge power c of compressed air energy storage, and the lower limit value q of the range constraint for the load rate δ1 of the coal-fired unit is generated; combined with the range constraint of the load rate δ1 of the coal-fired unit itself: δ1∈[30,100], the range constraint of the load rate δ1 of the coal-fired unit under this working condition is obtained: δ1∈[30,100]∩[q,+∞), and according to the precondition for entering the first working condition (1-1-1): the grid dispatch demand N is less than or equal to the sum of the rated power supply power z of the coal-fired unit and the rated discharge power c of compressed air energy storage, it can be obtained that q∈(-∞,100].

[0108] When the remaining operation time of a certain dispatch instruction before operating this working condition is t, whether the coupled system switches working conditions within the operation time t, that is, whether the compressed air energy storage is completely discharged, is constrained by the following conditions: The discharge power c' of compressed air energy storage is equal to the grid dispatch demand N minus the actual power supply power z' of the coal-fired unit. To ensure that within the operation time t, the discharge capacity of compressed air energy storage is less than or equal to all the dischargeable capacity r stored in the compressed air energy storage before operating this working condition, it is necessary to increase the load rate δ1 of the coal-fired unit as much as possible to reduce the discharge power c' of compressed air energy storage, so as to achieve a longer discharge process of compressed air energy storage. This constraint generates the lower limit value d of the range constraint for the load rate δ1 of the coal-fired unit n , forming the following judgment conditions: (1) When the load rate δ1 of the coal-fired unit δ1∈[30,100]∩[q,+∞)∩[d n ,+∞), the coupled system does not switch working conditions (t j = t); (2) When the load rate δ1 of the coal-fired unit δ1∈[30,100]∩[q,+∞)∩(-∞, d n ), the coupled system switches working conditions (t j <t). After operating for t j this working condition is switched to a working condition in the primary screening working condition set when the electric quantity r of compressed air energy storage is 0, that is, the second primary screening working condition set.

[0109] If both (1) and (2) have their respective value ranges of the load rate δ1 of the coal-fired unit, it is necessary to compare the unit power supply income Q of the coupled system under the two situations, and take the load rate δ1 of the coal-fired unit that can obtain a larger unit power supply income Q and its corresponding discharge load rate δ2 of compressed air energy storage as the final output distribution of the coupled system under this working condition.

[0110] In this working condition, the compressed air energy storage discharge load rate δ2 is equal to the ratio of the compressed air energy storage discharge power c' to its rated discharge power c, and the compressed air energy storage discharge power c' is equal to the difference between the grid dispatching demand N and the actual power supply power z' of the coal-fired unit; the per-unit power supply revenue Q of the coupled system and the revenue W of the coupled system are calculated according to the operating revenue model established in the first step.

[0111] 2. The Second Working Condition (1-1-2) This working condition adopts the joint power supply mode of coal-fired unit and compressed air energy storage. According to the precondition for entering the second working condition (1-1-2): the grid dispatching demand N is greater than the sum of the rated power supply power z of the coal-fired unit and the rated discharge power c of compressed air energy storage. In order to make the power supply power of the coupled system as close as possible to the grid dispatching demand N, both the coal-fired unit load rate δ1 and the compressed air energy storage discharge load rate δ2 under this working condition are 100%.

[0112] When the remaining operating time of a certain dispatching instruction before operating this working condition is t, whether the coupled system switches working conditions within the operating time t, that is, whether the compressed air energy storage is completely discharged, is judged according to the following conditions: (1) When the product of the rated discharge power c of compressed air energy storage and the remaining operating time t is less than or equal to the total dischargeable electricity r stored by compressed air energy storage before operating this working condition, the coupled system does not switch working conditions (t j = t); (2) When the product of the rated discharge power c of compressed air energy storage and the remaining operating time t is greater than the total dischargeable electricity r stored by compressed air energy storage before operating this working condition, the coupled system switches working conditions (t j < t). After this working condition operates for t j hours, it switches to the working condition in the primary screened working condition set when the electricity r of compressed air energy storage is 0, that is, the second primary screened working condition set.

[0113] In this working condition, both the coal-fired unit load rate δ1 and the compressed air energy storage discharge load rate δ2 are 100%, and the per-unit power supply revenue Q of the coupled system and the revenue W of the coupled system are calculated according to the operating revenue model established in the first step.

[0114] 3. The Third Working Condition (1-2) This working condition adopts the independent power supply mode of coal-fired unit, and does not involve working condition switching.

[0115] According to the precondition for entering the third working condition (1-2): the grid dispatching demand N is greater than or equal to the rated power supply power z of the coal-fired unit. In order to make the power supply power of the coupled system as close as possible to the grid dispatching demand N, the coal-fired unit load rate δ1 under this working condition is 100%. The per-unit power supply revenue Q of the coupled system and the revenue W of the coupled system are calculated according to the operating revenue model established in the first step.

[0116] 4. Fourth working condition (1-3-1) This working condition adopts the independent power supply mode of compressed air energy storage. According to the precondition for entering the fourth working condition (1-3-1): the grid dispatching demand N is greater than or equal to the rated power supply power z of the coal-fired unit and less than or equal to the rated discharge power c of compressed air energy storage, and the discharge power c' of compressed air energy storage under this working condition is equal to the grid dispatching demand N.

[0117] When the remaining operation duration of a certain dispatching instruction before operating this working condition is t, whether the coupled system switches working conditions within the operation duration t, that is, whether the compressed air energy storage is completely discharged, is judged according to the following conditions: (1) When the product of the grid dispatching demand N and the remaining operation duration t is less than or equal to the total available discharge capacity r stored by the compressed air energy storage before operating this working condition, the coupled system does not switch working conditions (t j = t); (2) When the product of the grid dispatching demand N and the remaining operation duration t is greater than the total available discharge capacity r stored by the compressed air energy storage before operating this working condition, the coupled system switches working conditions (t j <t). After this working condition operates for t j duration, it switches to a working condition within the primary screening working condition set when the compressed air energy storage capacity r is 0, that is, the second primary screening working condition set.

[0118] In this working condition, the discharge load rate δ2 of compressed air energy storage is equal to the ratio of the grid dispatching demand N to the rated discharge power c of compressed air energy storage, and the unit power supply revenue Q of the coupled system and the revenue W of the coupled system are calculated according to the operation revenue model established in the first step.

[0119] 5. Fifth working condition (1-3-2) This working condition adopts the independent power supply mode of compressed air energy storage. According to the precondition for entering the fifth working condition (1-3-2): the grid dispatching demand N is greater than or equal to the rated power supply power z of the coal-fired unit and greater than the rated discharge power c of compressed air energy storage. In order to make the power supply power of the coupled system as close as possible to the grid dispatching demand N, the discharge load rate δ2 of compressed air energy storage in this working condition is 100%.

[0120] When the remaining operation duration of a certain dispatching instruction before operating this working condition is t, whether the coupled system switches working conditions within the operation duration t, that is, whether the compressed air energy storage is completely discharged, is judged according to the following conditions: (1) When the product of the rated discharge power c of compressed air energy storage and the remaining operation duration t is less than or equal to the total available discharge capacity r stored by the compressed air energy storage before operating this working condition, the coupled system does not switch working conditions (t j = t); (2) When the product of the rated discharge power c of the compressed air energy storage and the remaining operation duration t is greater than the total dischargeable electricity r stored in the compressed air energy storage before the operation condition is executed, the coupled system switches the operation condition (t j <t). After this operation condition has been operated for t j duration, it switches to an operation condition within the primary screening operation condition set where the electricity r of the compressed air energy storage is 0, that is, the second primary screening operation condition set.

[0121] In this operation condition, the discharge load rate δ2 of the compressed air energy storage is 100%, and the unit power supply benefit Q of the coupled system and the benefit W of the coupled system are calculated according to the operation benefit model established in the first step.

[0122] 6. Sixth Operation Condition (2-1) This operation condition adopts the joint power supply mode of the coal-fired unit and the compressed air energy storage, wherein the excess output of the coal-fired unit charges the compressed air energy storage. This operation condition is constrained by the fact that the actual power supply power z' of the coal-fired unit is greater than the grid dispatching demand N, which generates the lower limit value l for the range constraint of the coal-fired unit load rate δ1; and the rated charging power b constraint of the compressed air energy storage generates the upper limit value o for the range constraint of the coal-fired unit load rate δ1; combined with the range constraint of the coal-fired unit load rate δ1 itself: δ1∈[30,100], the range constraint of the coal-fired unit load rate δ1 under this operation condition is obtained: δ1∈[30,100]∩(l,+∞)∩(-∞,o], and according to the precondition for entering the sixth operation condition (2-1): the grid dispatching demand N is greater than or equal to 30% of the rated power supply power z of the coal-fired unit and less than the rated power supply power z of the coal-fired unit, it can be obtained that l∈[30,100).

[0123] When the remaining operation duration of a certain dispatching instruction before executing this operation condition is t, whether the coupled system switches the operation condition within the operation duration t, that is, whether the compressed air energy storage is fully charged, is constrained by the following conditions: The charging power b' of the compressed air energy storage is equal to the actual power supply power z' of the coal-fired unit minus the grid dispatching demand N. To achieve that within the operation duration t, the sum of the dischargeable electricity obtained by charging the compressed air energy storage and the dischargeable electricity r stored in the compressed air energy storage before executing this operation condition is less than or equal to the rated capacity R of the compressed air energy storage, it is necessary to reduce the coal-fired unit load rate δ1 as much as possible to reduce the charging power b' of the compressed air energy storage, so as to realize a longer charging process of the compressed air energy storage. This constraint condition generates the upper limit value v for the range constraint of the coal-fired unit load rate δ1, forming the following judgment conditions: (1) When the coal-fired unit load rate δ1∈[30,100]∩(l,+∞)∩(-∞,o]∩(-∞,v], the coupled system does not switch the operation condition (t j = t); (2) When the load rate δ₁ of the coal-fired unit satisfies δ₁∈[30,100]∩(l,+∞)∩(-∞,o]∩(v,+∞), the coupled system switches the working condition (t j <t). This working condition operates for t j and then switches to a working condition within the primary screening working condition set where the compressed air energy storage electricity r is the rated capacity R, that is, the fifth primary screening working condition set.

[0124] If (1) and (2) both have respective value ranges for the load rate δ₁ of the coal-fired unit, it is necessary to compare the value of the unit power supply revenue Q of the coupled system under the two scenarios, and take the load rate δ₁ of the coal-fired unit that can obtain a larger unit power supply revenue Q and the corresponding compressed air energy storage charging load rate δ₃ as the final output distribution of the coupled system under this working condition.

[0125] In this working condition, the compressed air energy storage charging load rate δ₃ is equal to the ratio of the compressed air energy storage charging power b' to its rated charging power b, and the compressed air energy storage charging power b' is equal to the difference between the actual power supply power z' of the coal-fired unit and the grid dispatching demand N; the unit power supply revenue Q of the coupled system and the revenue W of the coupled system are calculated according to the operating revenue model established in the first step.

[0126] 7. Seventh working condition (2-2) This working condition adopts the independent power supply mode of the coal-fired unit, and does not involve working condition switching.

[0127] According to the precondition for entering the seventh working condition (2-2): the grid dispatching demand N is greater than or equal to 30% of the rated power supply power z of the coal-fired unit and less than the rated power supply power z of the coal-fired unit. In this working condition, the actual power supply power z' of the coal-fired unit is equal to the grid dispatching demand N.

[0128] In this working condition, the load rate δ₁ of the coal-fired unit is equal to the ratio of the grid dispatching demand N to the rated power supply power z of the coal-fired unit, and the unit power supply revenue Q of the coupled system and the revenue W of the coupled system are calculated according to the operating revenue model established in the first step.

[0129] 8. Eighth working condition (2-3-1) This working condition adopts the independent power supply mode of compressed air energy storage. According to the precondition for entering the eighth working condition (2-3-1): the grid dispatching demand N is greater than or equal to 30% of the rated power supply power z of the coal-fired unit, less than the rated power supply power z of the coal-fired unit, and less than or equal to the rated discharge power c of compressed air energy storage. In this working condition, the discharge power c' of compressed air energy storage is equal to the grid dispatching demand N.

[0130] When the remaining operating time of a certain dispatching instruction before operating this working condition is t, whether the coupled system switches the working condition within the operating time t, that is, whether the compressed air energy storage is completely discharged, is judged according to the following conditions: (1) When the product of the power grid dispatching demand N and the remaining operation time t is less than or equal to the total dischargeable electric quantity r stored in the compressed air energy storage before operating the working condition, the coupled system does not switch the working condition (t j = t); (2) When the product of the power grid dispatching demand N and the remaining operation time t is greater than the total dischargeable electric quantity r stored in the compressed air energy storage before operating the working condition, the coupled system switches the working condition (t j <t). After this working condition operates for t j hours, it switches to a working condition within the primary screened working condition set when the electric quantity r of the compressed air energy storage is 0, that is, the sixth primary screened working condition set.

[0131] In this working condition, the discharge load rate δ2 of the compressed air energy storage is equal to the ratio of the power grid dispatching demand N to the rated discharge power c of the compressed air energy storage, and the unit power supply收益 Q of the coupled system and the收益 W of the coupled system are calculated according to the operation收益 model established in the first step.

[0132] 9. The ninth working condition (2-3-2) This working condition adopts the independent power supply mode of compressed air energy storage. According to the precondition for entering the ninth working condition (2-3-2): the power grid dispatching demand N is greater than or equal to 30% of the rated power supply power z of the coal-fired unit, less than the rated power supply power z of the coal-fired unit, and greater than the rated discharge power c of the compressed air energy storage. In order to make the power supply power of the coupled system as close as possible to the power grid dispatching demand N, the discharge load rate δ2 of the compressed air energy storage in this working condition is 100%.

[0133] When the remaining operation time of a certain dispatching command before operating this working condition is t, whether the coupled system switches the working condition within the operation time t, that is, whether the compressed air energy storage is completely discharged, is judged according to the following conditions: (1) When the product of the rated discharge power c of the compressed air energy storage and the remaining operation time t is less than or equal to the total dischargeable electric quantity r stored in the compressed air energy storage before operating the working condition, the coupled system does not switch the working condition (t j = t); (2) When the product of the rated discharge power c of the compressed air energy storage and the remaining operation time t is greater than the total dischargeable electric quantity r stored in the compressed air energy storage before operating the working condition, the coupled system switches the working condition (t j <t). After this working condition operates for t j hours, it switches to a working condition within the primary screened working condition set when the electric quantity r of the compressed air energy storage is 0, that is, the sixth primary screened working condition set.

[0134] In this working condition, the discharge load rate δ2 of the compressed air energy storage is 100%, and the unit power supply收益 Q of the coupled system and the收益 W of the coupled system are calculated according to the operation收益 model established in the first step.

[0135] 10. The tenth working condition (3-1-1) In this working condition, the coal-fired unit and the compressed air energy storage adopt a joint power supply mode, and the excess output of the coal-fired unit is used to charge the compressed air energy storage. According to the precondition for entering the tenth working condition (3-1-1): the power grid dispatch demand N is less than 30% of the rated power supply power z of the coal-fired unit and less than the minimum output of the coupling system, in order to make the power supply power of the coupling system as close as possible to the power grid dispatch demand N, the load rate δ₁ of the coal-fired unit in this working condition is 30%, and the charging load rate δ₃ of the compressed air energy storage is 100%.

[0136] When the remaining operation time of a dispatch instruction before operating this working condition is t, whether the coupling system switches working conditions within the operation time range t, that is, whether the compressed air energy storage is fully charged, is constrained by the following conditions: (1) When the sum of the dischargeable electric energy obtained from the charging of compressed air energy storage and the stored dischargeable electric energy r before operating this working condition is less than or equal to the rated capacity R of compressed air energy storage, the coupling system does not switch working conditions (t j = t); (2) When the sum of the dischargeable electric energy obtained from the charging of compressed air energy storage and the stored dischargeable electric energy r before operating this working condition is greater than the rated capacity R of compressed air energy storage, the coupling system switches working conditions (t j <t). After operating for t j hours, this working condition is switched to a working condition in the primary screening working condition set where the electric quantity r of compressed air energy storage is under the rated capacity R, that is, the ninth primary screening working condition set.

[0137] In this working condition, the load rate δ₁ of the coal-fired unit is 30%, the charging load rate δ₃ of the compressed air energy storage is 100%, and the unit power supply revenue Q of the coupling system and the total revenue W of the coupling system are calculated according to the operation revenue model established in the first step.

[0138] 11. The eleventh working condition (3-1-2) In this working condition, the coal-fired unit and the compressed air energy storage adopt a joint power supply mode, and the excess output of the coal-fired unit is used to charge the compressed air energy storage.

[0139] This working condition is constrained by that the actual power supply power z' of the coal-fired unit is greater than the power grid dispatch demand N, which generates the lower limit value l of the range constraint for the load rate δ₁ of the coal-fired unit; and the constraint from the rated charging power b of the compressed air energy storage generates the upper limit value o of the range constraint for the load rate δ₁ of the coal-fired unit; combined with the range constraint of the coal-fired unit load rate δ₁ itself: δ₁∈[30,100], the range constraint of the coal-fired unit load rate δ₁ under this working condition is obtained: δ₁∈[30,100]∩(l,+∞)∩(-∞,o], and according to the precondition for entering the eleventh working condition (3-1-2): the power grid dispatch demand N is less than 30% of the rated power supply power z of the coal-fired unit and greater than or equal to the minimum output of the coupling system, it can be obtained that l∈[0,30).

[0140] When the remaining operation duration of a scheduling instruction before the operating condition is t, whether the coupled system switches the operating condition within the operation duration t, that is, whether the compressed air energy storage is fully charged, is constrained by the following conditions: The charging power b' of compressed air energy storage is equal to the difference between the actual power supply power z' of the coal-fired unit and the power grid dispatching demand N. To ensure that within the operation duration t, the sum of the dischargeable electric energy obtained by charging the compressed air energy storage and the stored dischargeable electric energy r of the compressed air energy storage before operating this working condition is less than or equal to the rated capacity R of the compressed air energy storage, it is necessary to reduce δ1 as much as possible to reduce the charging power b' of the compressed air energy storage, so as to achieve a longer charging process of compressed air energy storage. This constraint condition gives the upper limit value v for the range constraint of the coal-fired unit load rate δ1, and forms the following judgment conditions: (1) When the coal-fired unit load rate δ1∈[30,100]∩(l,+∞)∩(-∞,o]∩(-∞,v], the coupled system does not switch the working condition (t j = t); (2) When the coal-fired unit load rate δ1∈[30,100]∩(l,+∞)∩(-∞,o]∩(v,+∞), the coupled system switches the working condition (t j <t). After this working condition operates for t j duration, it is switched to a working condition in the primary screening working condition set where the electric quantity r of compressed air energy storage is under the rated capacity R, that is, the ninth primary screening working condition set.

[0141] If both (1) and (2) have their respective value ranges of the coal-fired unit load rate δ1, it is necessary to compare the unit power supply收益 Q of the coupled system under the two conditions, and take the coal-fired unit load rate δ1 that can obtain a larger unit power supply收益 Q and the corresponding compressed air energy storage charging load rate δ3 as the final output distribution of the coupled system under this working condition.

[0142] The compressed air energy storage charging load rate δ3 under this working condition is equal to the ratio of the compressed air energy storage charging power b' to its rated charging power b, and the compressed air energy storage charging power b' is equal to the difference between the actual power supply power z' of the coal-fired unit and the power grid dispatching demand N; the unit power supply收益 Q of the coupled system and the coupled system收益 W are calculated according to the operation收益 model established in the first step.

[0143] 12. The twelfth working condition (3-2) This working condition adopts the independent power supply mode of coal-fired unit and does not involve working condition switching.

[0144] According to the precondition for entering the twelfth working condition (3-2): this working condition needs to satisfy that the grid dispatching requirement N is less than 30% of the rated power supply power z of the coal-fired unit. In order to make the power supply power of the coupled system as close as possible to the grid dispatching requirement N, the load rate δ₁ of the coal-fired unit under this working condition is 30%. The unit power supply revenue Q of the coupled system and the revenue W of the coupled system are calculated according to the operating revenue model established in the first step.

[0145] 13. The Thirteenth Working Condition (3-3-1) This working condition adopts the independent power supply mode of compressed air energy storage. According to the precondition for entering the thirteenth working condition (3-3-1): the grid dispatching requirement N is less than 30% of the rated power supply power z of the coal-fired unit and less than or equal to the rated discharge power c of the compressed air energy storage. Under this working condition, the discharge power c' of the compressed air energy storage is equal to the grid dispatching requirement N.

[0146] When the remaining operating duration of a certain dispatching instruction before operating this working condition is t, whether the coupled system switches the working condition within the operating duration t, that is, whether the compressed air energy storage is completely discharged, is judged according to the following conditions: (1) When the product of the grid dispatching requirement N and the remaining operating duration t is less than or equal to the total available discharge capacity r stored in the compressed air energy storage before operating this working condition, the coupled system does not switch the working condition (t j = t); (2) When the product of the grid dispatching requirement N and the remaining operating duration t is greater than the total available discharge capacity r stored in the compressed air energy storage before operating this working condition, the coupled system switches the working condition (t j < t). After this working condition operates for t j duration, it switches to the working condition in the primary screening working condition set when the compressed air energy storage capacity r is 0, that is, the tenth primary screening working condition set.

[0147] Under this working condition, the discharge load rate δ₂ of the compressed air energy storage is equal to the ratio of the grid dispatching requirement N to the rated discharge power c of the compressed air energy storage. The unit power supply revenue Q of the coupled system and the revenue W of the coupled system are calculated according to the operating revenue model established in the first step.

[0148] 14. The Fourteenth Working Condition (3-3-2) This working condition adopts the independent power supply mode of compressed air energy storage. According to the precondition for entering the fourteenth working condition (3-3-2): the grid dispatching requirement N is less than 30% of the rated power supply power z of the coal-fired unit and greater than the rated discharge power c of the compressed air energy storage. In order to make the power supply power of the coupled system as close as possible to the grid dispatching requirement N, the discharge load rate δ₂ of the compressed air energy storage under this working condition is 100%.

[0149] When the remaining operating time of a scheduling instruction before operating the working condition is t, whether the coupled system switches working conditions within the range of the operating time t, that is, whether the compressed air energy storage is completely discharged, is judged according to the following conditions: (1) When the product of the rated discharge power c of the compressed air energy storage and the remaining operating time t is less than or equal to the total dischargeable electric quantity r stored in the compressed air energy storage before operating the working condition, the coupled system does not switch the working condition (t j = t); (2) When the product of the rated discharge power c of the compressed air energy storage and the remaining operating time t is greater than the total dischargeable electric quantity r stored in the compressed air energy storage before operating the working condition, the coupled system switches the working condition (t j <t). After this working condition operates for t j , it switches to a working condition within the primary screening working condition set when the electric quantity r of the compressed air energy storage is 0, that is, the tenth primary screening working condition set.

[0150] In this working condition, the discharge load rate δ2 of compressed air energy storage is 100%, and the unit power supply income Q of the coupled system and the income W of the coupled system are calculated according to the operating income model established in the first step.

[0151] Through the above four steps, with the goal of maximizing the operating income of the coupled system, the final working condition of a certain power grid dispatching instruction within a certain time range and the operation of the working condition are determined, which mainly includes four key contents: whether the power supply mode of the coupled system and the power supply power under the current power supply mode meet the power grid dispatching demand N, the load rate δ1 of the coal-fired unit, the charge / discharge load rate of compressed air energy storage (δ3 or δ2), and the income W of the coupled system.

[0152] This embodiment further includes: changes of electric quantity and discharge cost during the charging and discharging process of compressed air energy storage.

[0153] When the coal-fired unit is at different load rates, the coal consumption per unit electric quantity charged by compressed air energy storage is different, that is, the charging cost is different. Therefore, the present invention classifies different charging costs and their corresponding charging electric quantities. The classified electric quantities and costs are uniformly measured by the subsequently dischargeable electric quantity and unit discharge cost u of compressed air energy storage, and arranged from low to high according to the unit discharge cost. During the discharge process of compressed air energy storage, the electric quantity with lower unit discharge cost u is preferentially discharged until the operation of the power grid dispatching instruction is finished or all the gear electric quantity is completely discharged.

[0154] The following is a schematic diagram of classification of the dischargeable electric quantity r and unit discharge cost u of compressed air energy storage at a certain moment.

[0155]

[0156] 1. When compressed air stores energy and discharges, the following operating conditions are involved: First operating condition (1-1-1), Second operating condition (1-1-2), Fourth operating condition (1-3-1), Fifth operating condition (1-3-2), Eighth operating condition (2-3-1), Ninth operating condition (2-3-2), Thirteenth operating condition (3-3-1), and Fourteenth operating condition (3-3-2): (1) Does not involve switching of operating conditions If the compressed air energy storage releases the first i-th level of electricity (r1, r2, r3...r... i ), then according to r i Whether the battery level is completely discharged determines the following two new categories: 1) r i Battery not fully discharged

[0157] 2) r i The battery level was just fully discharged.

[0158] (2) Involves switching of operating conditions The discharge capacity r of compressed air energy storage is 0, and the discharge capacity r and unit discharge cost u are cleared.

[0159] 2. When compressed air is used for energy storage and charging, the following operating conditions are involved: Condition 6 (2-1), Condition 10 (3-1-1), and Condition 11 (3-1-2): New discharge capacity r i The corresponding unit discharge cost u i Adding the original unit discharge cost u1, u2, u3...u n The sequence is rearranged from lowest to highest to form new r1, r2, r3...r n r n+1 and corresponding u1, u2, u3...u n u n+1 ; if u i Compared with the original unit discharge cost u1, u2, u3...u n If any one of the numbers in the sequence is equal, the additional dischargeable quantity r i Automatically add r1, r2, r3...r n The corresponding terms in the sequence only affect r1, r2, r3...r n The numerical change of a term in the sequence is still divided into r1, r2, r3...r n and corresponding u1, u2, u3...u n .

[0160] Example 2: This embodiment demonstrates the optimized scheduling method of the coal-fired unit coupled with compressed air energy storage system in this invention, taking into account specific coal-fired units, compressed air energy storage installations, performance parameters, and electricity prices as boundary conditions. This embodiment involves three states of grid scheduling demand N and rated power supply z of the coal-fired unit. The compressed air energy storage capacity r is between 0 and the rated capacity R, that is, the compressed air energy storage can be both charged and discharged.

[0161] The input parameters for coal-fired power units are shown in the table below.

[0162] Rated generating capacity a (MW) of a coal-fired power unit 1000 <![CDATA[Plant power consumption rate ε₁ of coal-fired units (%)]]> 4 <![CDATA[Standard coal consumption for power generation m1 (g / kWh) of coal-fired units under rated power generation power]]> 259.401 Standard coal consumption rate (m / kWh) for power generation at actual power output of coal-fired units See "Parameters and their meanings in the examples" for coal-fired unit input parameters (4). <![CDATA[Standard coal price MP1 (yuan / t)]]> 1200 <![CDATA[On-grid electricity price MP2 of coal-fired units (yuan / kWh)]]> 0.4153 <![CDATA[Deep peak shaving subsidy benchmark load rate δ₀ (%) of coal-fired units]]> 50 Deep peak-shaving subsidy for coal-fired power units (yuan / kWh) 0.2 Fuel cost as a percentage of the variable costs of coal-fired power units (p) 80 The input parameters for compressed air energy storage are shown in the table below.

[0163] Rated charging power b (MW) for compressed air energy storage 400 <![CDATA[Rated charging duration of compressed air energy storage t1 (h)]]> 8 <![CDATA[Rated discharge duration of compressed air energy storage t2 (h)]]> 4 <![CDATA[Efficiency η₂ of compressed air energy storage system (%)]]><![CDATA[]]>< 70 <![CDATA[Initial electric energy of compressed air energy storage r0 (MWh)]]> 1120 Initial charging price for compressed air energy storage (YM / kWh) 0.2800 Compressed air energy storage grid connection price YF (yuan / kWh) 0.4153

[0164] (a) The grid dispatch demand N is greater than or equal to the rated power supply z of the coal-fired power unit.

[0165] The power grid dispatch demand N is 1200MW, the dispatch command runtime t0 is 5h, and the operation status of the coupled system is shown in the table below.

[0166]

[0167] (ii) The grid dispatch demand N is greater than or equal to 30% of the rated power supply z of the coal-fired power units and less than the rated power supply z of the coal-fired power units.

[0168] The power grid dispatch demand N is 400MW, the dispatch command runtime t0 is 5h, and the operation status of the coupled system is shown in the table below.

[0169]

[0170] (iii) The grid dispatch demand N is less than 30% of the rated power supply z of coal-fired units.

[0171] The power grid dispatch demand N is 200MW, the dispatch command runtime t0 is 5h, and the operation status of the coupled system is shown in the table below.

[0172]

[0173] The parameters and their meanings in the embodiments: (I) Input parameters.

[0174] 1. Power grid dispatch instructions.

[0175] (1) Duration t0 (h) of scheduling instructions: If multiple scheduling instructions are involved, the duration is defined as t0 (h) in sequence. 01 , t 02 , t 03 …t 0n .

[0176] (2) Power grid dispatch demand N (MW).

[0177] 2. Parameters of coal-fired power units.

[0178] (1) Rated power generation capacity a (MW) of coal-fired unit.

[0179] (2) Plant power consumption rate of coal-fired unit ε1 (%): The proportion of the power consumption of the equipment in the plant of coal-fired unit to the rated power generation a of the coal-fired unit.

[0180] (3) Standard coal consumption rate m1 (g / kWh) of coal-fired unit at rated power: The mass (g) of standard coal consumed per kWh of electricity generated by the coal-fired unit when it is running at rated power a.

[0181] (4) Standard coal consumption rate m (g / kWh) under actual power generation of coal-fired unit: The mass (g) of standard coal consumed per kWh of electricity generated by coal-fired unit when it is operating at a non-rated power generation a (measured data).

[0182] The actual power generation a' (MW) of the coal-fired unit and its corresponding standard coal consumption rate m (g / kWh) in this embodiment are shown in the table below.

[0183] 1000 259.401 900.049 259.872 850.005 260.451 800.032 261.030 750.036 261.681 500.015 269.858 400.075 276.372 300.020 285.635

[0184] (5) Standard coal price MP1 (yuan / t).

[0185] (6) On-grid electricity price of coal-fired power units MP2 (yuan / kWh).

[0186] (7) Base load rate δ0 (%) for deep peak shaving subsidy for coal-fired units: When the operating load rate of coal-fired units drops below δ0, they can start to receive deep peak shaving subsidies.

[0187] (8) Deep peak shaving subsidy for coal-fired units e (yuan / kWh): The subsidy amount obtained for each kWh of electricity generated when the operating load rate of a coal-fired unit drops below the benchmark load rate δ0.

[0188] (9) The proportion of fuel cost in the variable cost of coal-fired power units p (%): The variable cost of power generation of coal-fired power units includes fuel cost, environmental protection cost and operation and maintenance cost, etc.

[0189] 3. Compressed air energy storage parameters.

[0190] (1) Rated charging power b (MW) for compressed air energy storage.

[0191] (2) Rated charging time t1 (h) for compressed air energy storage.

[0192] (3) Rated discharge time t2 (h) of compressed air energy storage.

[0193] (4) Compressed air energy storage system efficiency η2 (%).

[0194] (5) Initial energy of compressed air storage r0 (MWh): The maximum energy that can be released in the initial state of compressed air storage.

[0195] (6) Initial electricity charge price YM (yuan / kWh) for compressed air energy storage: The initial electricity may come from various power sources such as new energy sources and coal-fired units, and the corresponding charging price needs to be entered.

[0196] (7) Compressed air energy storage grid connection price YF (yuan / kWh).

[0197] (ii) Intermediate parameters.

[0198] (1) Standard coal consumption rate m (g / kWh) under actual power generation of coal-fired unit: The mass (g) of standard coal consumed per kWh of electricity generated by coal-fired unit when it is running at actual power generation a' (data calculated by fitting function).

[0199] Based on the input data in the coal-fired unit parameter (4) of the input parameters, the fitting function relationship between the actual power generation a' of the coal-fired unit and the standard coal consumption rate m is obtained. The schematic diagram of the fitting function relationship is shown below. Figure 3 As shown in the table below, the calculated data and the measured data of the fitting function are:

[0200] Based on the above fitting function relationship, the standard coal consumption rate m of the coal-fired unit under any actual power generation a' can be calculated.

[0201] (2) Rated power supply z (MW) of coal-fired unit: the external power supply after deducting the plant power consumption power from the rated power a of coal-fired unit.

[0202] (3) Rated discharge power of compressed air energy storage c (MW): Rated charging power of compressed air energy storage b multiplied by rated charging time t1 multiplied by system efficiency η2 divided by rated discharge time t2.

[0203] (4) The remaining runtime t (h) after a certain scheduling instruction runs a certain working condition: the remaining runtime t before running the working condition minus the runtime t of the working condition. j .

[0204] (5) Compressed air energy storage discharge capacity r (MWh): The maximum amount of electricity that compressed air energy storage can release at a certain moment.

[0205] (6) Rated capacity of compressed air energy storage R (MWh): The maximum amount of discharge that compressed air energy storage can store is the product of the rated charging power b, the rated charging time t1, and the system efficiency η2.

[0206] (7) Unit discharge cost of compressed air energy storage u (yuan / kWh): The ratio of the charging cost of compressed air energy storage to the amount of electricity that can be released after the charging amount.

[0207] (8) Unit discharge cost of initial energy of compressed air energy storage u0 (yuan / kWh): initial energy of compressed air energy storage charging price YM divided by the efficiency of compressed air energy storage system η2.

[0208] (9) Power Supply S (MWh): The power supply of the coupled system to the outside world within a certain time range. When the output of the coupled system meets or exceeds the grid dispatch demand N, the power supply S is equal to the operating time t under a certain operating condition. j The product of the power supply and the grid dispatch demand N; when the output of the coupled system is lower than the grid dispatch demand N, the power supply S is equal to the operating time t under a certain operating condition. j The product of the maximum power supplied by the coupled system.

[0209] (10) Unit power supply revenue Q (yuan / MWh): The ratio of the revenue W of the coupled system to the power supply S.

[0210] (11) The lower limit q of the load factor δ1 range constraint of coal-fired units: The lower limit q of the load factor δ1 of coal-fired units under the constraint of the rated discharge power c of compressed air energy storage is generated to meet the grid dispatch demand N. It is the ratio of the difference between the grid dispatch demand N and the rated discharge power c of compressed air energy storage to the rated power supply z of coal-fired units.

[0211] (12) Lower limit d of the load rate range constraint of coal-fired unit δ1 n The lower limit of the load factor δ1 of the coal-fired unit under the non-switching operating condition is generated by the constraint of the dischargeable amount r of compressed air energy storage. It is the ratio of the grid dispatch demand minus the dischargeable amount r of compressed air energy storage to the remaining running time t before a certain dispatch instruction is executed under this operating condition, divided by the rated power supply power z of the coal-fired unit.

[0212] (13) The lower limit l of the load factor δ1 range constraint of coal-fired unit: The lower limit l of the load factor δ1 of coal-fired unit under the constraint that the actual power supply z' of coal-fired unit is greater than the grid dispatch demand N is generated. It is the ratio of grid dispatch demand N to the rated power supply z of coal-fired unit.

[0213] (14) Upper limit of the load factor δ1 range constraint of coal-fired unit: The upper limit of the load factor δ1 of coal-fired unit under the constraint of the rated charging power b of compressed air energy storage is generated to meet the grid dispatch demand N. It is the ratio of the sum of grid dispatch demand N and rated charging power b of compressed air energy storage to the rated power supply z of coal-fired unit.

[0214] (15) Upper limit v of the load factor δ1 range constraint of coal-fired unit: The upper limit of the load factor δ1 of coal-fired unit under non-switching conditions is generated by the constraint of the rated capacity R of compressed air energy storage. It is the difference between the rated capacity R of compressed air energy storage and the discharge capacity r of compressed air energy storage before operating under this condition, divided by the product of the remaining running time t before operating under a certain dispatching instruction and the efficiency η2 of the compressed air energy storage system, plus the grid dispatching demand N, and then divided by the rated power supply z of the coal-fired unit.

[0215] (iii) Output parameters.

[0216] (1) System demand output N (MW): i.e., grid dispatch demand N (MW) in the input parameters.

[0217] (2) Coal-fired unit load rate δ1 (%): The ratio of the actual power generation a' of the coal-fired unit to the rated power generation a, δ1∈[30,100].

[0218] (3) Compressed air energy storage discharge load rate δ2 (%): The ratio of the actual discharge power c' of compressed air energy storage to the rated discharge power c, δ2∈[0,100].

[0219] (4) Compressed air energy storage charging load rate δ3 (%): The ratio of the actual charging power of compressed air energy storage to the rated charging power b, δ3∈[0,100].

[0220] (5) Output of coal-fired unit z' (MW): The actual power supply of the coal-fired unit is the product of the rated power supply z of the coal-fired unit and the load rate δ1 of the coal-fired unit.

[0221] (6) Compressed air energy storage output c' (MW): The discharge power of compressed air energy storage at the discharge load rate δ2.

[0222] (7) Actual charging power b' (MW) of compressed air energy storage: the charging power of compressed air energy storage under the charging load rate δ3.

[0223] (8) Actual power generation of coal-fired unit a' (MW): Power generation of coal-fired unit at load rate δ1.

[0224] (9) The revenue W (yuan) of the coupled system.

[0225] (10) The runtime t of a certain scheduling instruction under a certain working conditionj (h): If multiple operating conditions are involved, the running time of each operating condition is defined as t in sequence. j1 , t j2 , t j3 …t jn .

[0226] (11) Compressed air energy storage discharge capacity r (MWh): same as intermediate parameter (5).

[0227] (12) Change in the dischargeable amount of compressed air energy storage Δr (MWh): The dischargeable amount of compressed air energy storage r after the last working condition under a certain scheduling instruction is completed minus the dischargeable amount of compressed air energy storage r before the scheduling instruction is completed ("positive" means the dischargeable amount r increases, "negative" means the dischargeable amount r decreases).

[0228] (13) Average unit discharge cost of compressed air energy storage capacity: The weighted average of the unit discharge cost of each power level in the compressed air energy storage capacity.

[0229] In summary, the optimized scheduling method for a coal-fired power unit coupled with compressed air energy storage system according to embodiments of the present invention, under the premise of prioritizing the needs of power grid dispatch, constructs an optimized scheduling mode of "power source + energy storage" under a new power system based on boundary conditions such as coal-fired power unit, compressed air energy storage capacity, performance parameters and electricity price given by the user. It can optimize the operation mode of the coal-fired power unit and compressed air energy storage coupled system for different power grid dispatch demand commands, thereby maximizing the operating benefits of the coupled system.

[0230] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An optimized scheduling method for a coal-fired power unit coupled with a compressed air energy storage system, characterized in that, include: S1: Mathematical modeling of the operational benefits for all operating conditions of the coupled system; S2: Based on the relationship between power grid dispatch demand and the rated power of coal-fired units, and the relationship between compressed air energy storage capacity and rated capacity, determine the selectable operating modes of the coupled system and obtain the initial screening working condition set. S3: The first principle is to meet the grid dispatching requirements, and the second principle is to maximize the unit power supply revenue of the coupled system. The final operating conditions are obtained by screening in the initial screening set of operating conditions. The screening principle is: (1) Prioritize the operating conditions that meet the grid dispatching requirements; (2) If there is an operating condition that meets (1), select the operating condition corresponding to the maximum unit power supply revenue of the coupled system as the operating condition. If there is no operating condition that satisfies (1), then select the operating condition corresponding to the maximum unit power supply revenue of the coupled system as the operating condition among the operating conditions that do not meet the grid dispatch requirements. S4: Obtain the coupled system revenue, coal-fired unit load rate and compressed air energy storage charging / discharging load rate corresponding to the maximum unit power supply revenue under the final operating conditions, and realize the operation scheduling of the coupled system.

2. The optimized scheduling method for a coal-fired unit coupled with compressed air energy storage system according to claim 1, characterized in that, S2 includes: the relationship between the power grid dispatch demand and the rated power supply of the coal-fired power unit includes: the power grid dispatch demand is greater than or equal to the rated power supply of the coal-fired power unit; the power grid dispatch demand is greater than or equal to 30% of the rated power supply of the coal-fired power unit and less than the rated power supply of the coal-fired power unit; the power grid dispatch demand is less than 30% of the rated power supply of the coal-fired power unit; the relationship between the compressed air energy storage capacity and the rated capacity includes: the compressed air energy storage capacity is equal to the rated capacity; the compressed air energy storage capacity is 0; the compressed air energy storage capacity is less than the rated capacity and greater than 0; the compressed air energy storage cannot be charged or discharged; combining the relationship between the power grid dispatch demand and the rated power supply of the coal-fired power unit, and the relationship between the compressed air energy storage capacity and the rated capacity, a set of initial screening conditions under 12 operating states is obtained.

3. The optimized scheduling method for a coal-fired unit coupled with compressed air energy storage system according to claim 1, characterized in that, Determine whether it is necessary to switch operating conditions based on whether the compressed air energy storage is fully discharged or fully charged under the current operating conditions.

4. The optimized scheduling method for a coal-fired unit coupled with compressed air energy storage system according to claim 3, characterized in that, If the current operating condition is that the coal-fired unit is supplying power alone, then there is no need to switch operating conditions.

5. An optimized scheduling method for a coal-fired power unit coupled with compressed air energy storage system according to claim 3 or 4, characterized in that, If a power supply mode switch occurs within the operating time t, and the current operating mode is where the grid dispatch demand is greater than or equal to 30% of the rated power supply of the coal-fired unit but less than the rated power supply of the coal-fired unit, or the grid dispatch demand is less than 30% of the rated power supply of the coal-fired unit and a coal-fired unit and compressed air energy storage co-power supply mode is adopted, then this operating mode will last for t. j After a certain period of time, switch to the operating condition within the set of primary screening operating conditions where the compressed air energy storage capacity is equal to the rated capacity; Under other operating conditions, running under the current operating condition for t j After a certain period of time, switch to the working condition set within the primary screening working condition set where the compressed air energy storage power is 0; The initial screening criteria remain unchanged after the operating conditions are switched.

6. An optimized scheduling method for a coal-fired power unit coupled with compressed air energy storage system according to claim 1, 2, 3, or 4, characterized in that, The initial energy of compressed air energy storage and the charging energy and charging cost obtained under different load rates of coal-fired units are classified into tiers. The energy and cost of the tiers are uniformly measured by the discharge energy that can be released by compressed air energy storage and the unit discharge cost, and are arranged from low to high according to the unit discharge cost. During the discharge process of compressed air energy storage, the energy with the lower unit discharge cost is released first, until the grid dispatch command is completed or all tiers of energy are released.

7. An optimized scheduling method for a coal-fired power unit coupled with compressed air energy storage system according to claim 1, 2, 3, or 4, characterized in that, The final operating conditions include: whether the power supply mode of the coupled system and the power supply power under the current power supply mode meet the grid dispatch requirements, the load rate of the coal-fired unit, the charging / discharging load rate of the compressed air energy storage, and the revenue of the coupled system.

8. The optimized scheduling method for a coal-fired unit coupled with compressed air energy storage system according to claim 7, characterized in that, The power supply modes of the coupling system include: coal-fired power units and compressed air energy storage jointly supplying power, coal-fired power units supplying power alone, and compressed air energy storage supplying power alone.

9. An optimized scheduling method for a coal-fired power unit coupled with compressed air energy storage system according to claim 1, 2, 3, or 4, characterized in that, When there are multiple scheduling instructions or a single scheduling instruction involves multiple operating conditions, an optimal combination of operating conditions is formed, and the operating conditions, coupled system benefits, and other relevant information are described in different time periods.

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