CN104850912A - Accounting method and accounting system for power generation marginal cost interval of thermal power unit - Google Patents

Abstract

The invention discloses a calculation method and a calculation device for marginal cost intervals of power generation of a thermal power unit, wherein the method comprises the following steps: obtaining a marginal heat consumption rate curve of power generation; obtaining performance parameters; calculating fuel incremental costs; and calculating no-load running costs; Calculate the average operation and maintenance cost; obtain the marginal cost of the thermal power unit according to the output level, performance parameters, fuel incremental cost, average operation and maintenance cost and no-load operation cost; calculate the power generation margin of the thermal power unit according to the fluctuation range of the marginal cost and operation and maintenance cost cost range. The calculation method of the embodiment of the present invention calculates the marginal cost range of power generation of the thermal power unit through the fluctuation range of the marginal cost and the operation and maintenance cost, thereby improving the accuracy of the calculation, having strong applicability and practicability, and being simple and convenient.

Description

Calculation Method and System of Marginal Cost Range of Thermal Power Units

technical field

The invention relates to the field of electric power technology, in particular to an accounting method and an accounting system for a thermal power unit generating marginal cost interval.

Background technique

The marginal cost accounting of thermal power generation is one of the core tasks to ensure the orderly operation and efficient supervision of the power spot market. Due to the economies of scale effect of power generation technology, the market concentration on the power generation side is often high. Under the price mechanism of marginal pricing, when the market supply and demand are tight or the network is congested, power generators have the internal motivation to use market power, control market prices, and obtain excess profits, which will cause sharp fluctuations in market prices, a substantial increase in transaction risks and market risks. A drastic drop in efficiency.

In order to ensure the orderly operation of the electricity market and implement efficient supervision, it is necessary to propose an effective accounting method for the marginal cost interval of thermal power generation. Participate in system scheduling, or further use the information of the calculated marginal cost range of unit power generation in corresponding innovative market design or supervision, thereby reducing the negative impact caused by information asymmetry and market power issues.

Contents of the invention

The present invention aims at solving one of the technical problems in the related art mentioned above at least to a certain extent.

For this reason, an object of the present invention is to propose a method for calculating the marginal cost range of thermal power units, which can improve the accuracy of calculation and has strong applicability and practicability.

Another object of the present invention is to propose a device for calculating intervals of marginal cost of power generation of thermal power units.

In order to achieve the above-mentioned purpose, an embodiment of the present invention proposes a method for calculating the marginal cost of power generation of a thermal power unit, including the following steps: obtaining the marginal heat rate of the thermal power unit to obtain the marginal heat rate curve of power generation of the thermal power unit Obtain the performance parameters of fuel consumption for power generation of the thermal power unit; obtain the fuel incremental cost of the thermal power unit according to the actual fuel price of the thermal power unit, the marginal heat rate curve of the power generation and the performance parameters; The actual fuel price, the heat that needs to be input during the no-load operation and the performance parameters are used to obtain the no-load operation cost of the thermal power unit; the average operation and maintenance cost of the thermal power unit is obtained; according to the output level, the performance parameters , the fuel incremental cost, the average operation and maintenance cost and the no-load operation cost to obtain the marginal cost of the thermal power unit; and calculate the power generation of the thermal power unit according to the fluctuation interval of the marginal cost and operation and maintenance cost marginal cost range.

According to the interval calculation method for the marginal cost of thermal power generating units proposed in the embodiment of the present invention, the marginal cost of the thermal power unit is obtained through the output level, performance parameters, fuel incremental cost, average operation and maintenance cost, and no-load operating cost, so that according to the marginal cost and The fluctuation interval of operation and maintenance costs realizes the purpose of calculating the marginal cost interval of thermal power generation, fully considers the physical characteristics and technical parameters of thermal power unit operation, and improves the accuracy of accounting through the fuel price and other related information submitted by thermal power units, and It is closely related to the actual operation of the power spot market, has strong applicability and practicability, and is simple and convenient.

In addition, according to the above-mentioned embodiment of the present invention, the marginal cost interval calculation method of the thermal power unit can also have the following additional technical features:

Further, in one embodiment of the present invention, the marginal heat consumption rate is the heat that needs to be input when increasing 1 MWh of electricity.

Further, in an embodiment of the present invention, the fuel incremental cost is obtained by multiplying the actual fuel price, the power generation marginal heat rate curve and the performance parameter.

Further, in an embodiment of the present invention, the obtaining the average operation and maintenance cost of the thermal power unit further includes: obtaining the average operation and maintenance cost by averaging the equivalent hourly operation and maintenance costs of multiple thermal power units, Wherein, the equivalent hourly operation and maintenance cost is equal to the ratio of the total maintenance cost to the equivalent operating time.

Further, in an embodiment of the present invention, the performance parameter is equal to the ratio of the actual total fuel consumption to the theoretical total fuel consumption, or equal to the ratio of the actual total heat input to the theoretical total heat input.

Another embodiment of the present invention proposes an interval calculation device for the marginal cost of power generation of a thermal power unit, including: a curve acquisition module, used to obtain the marginal heat rate of the thermal power unit to obtain the marginal heat rate curve of power generation of the thermal power unit The performance parameter acquisition module is used to acquire the performance parameters of the power generation fuel consumption of the thermal power unit; the incremental cost acquisition module is used to obtain the fuel consumption according to the actual fuel price of the thermal power unit, the marginal heat rate curve of the power generation and the The performance parameter obtains the fuel incremental cost of the thermal power unit; the no-load cost acquisition module is used to obtain the no-load cost of the thermal power unit according to the actual fuel price, the heat that needs to be input during the no-load operation, and the performance parameter. The average cost acquisition module is used to obtain the average operation and maintenance cost of the thermal power unit; the marginal cost acquisition module is used to obtain the average cost according to the output level, the performance parameters, the fuel incremental cost, and the average operation and maintenance cost cost and the no-load operation cost to obtain the marginal cost of the thermal power unit; and a cost range acquisition module, configured to calculate the marginal cost range of power generation of the thermal power unit according to the marginal cost and the fluctuation range of the operation and maintenance cost.

According to the thermal power generation marginal cost interval calculation device proposed in the embodiment of the present invention, the marginal cost of the thermal power unit is obtained through the output level, performance parameters, fuel incremental cost, average operation and maintenance cost, and no-load operation cost, thereby according to the marginal cost and The fluctuation interval of operation and maintenance costs realizes the purpose of calculating the marginal cost interval of thermal power generation, fully considers the physical characteristics and technical parameters of thermal power unit operation, and improves the accuracy of accounting through the fuel price and other related information submitted by thermal power units, and It is closely related to the actual operation of the power spot market, has strong applicability and practicability, and is simple and convenient.

In addition, according to the above-mentioned embodiments of the present invention, the marginal cost interval calculation device for power generation of thermal power units can also have the following additional technical features:

Further, in one embodiment of the present invention, the marginal heat consumption rate is the heat that needs to be input when increasing 1 MWh of electricity.

Further, in an embodiment of the present invention, the incremental cost acquisition module obtains the incremental fuel cost by multiplying the actual fuel price, the marginal heat rate curve of power generation and the performance parameter.

Further, in one embodiment of the present invention, the average cost obtaining module is specifically used to obtain the average operation and maintenance cost by averaging the equivalent hourly operation and maintenance costs of multiple thermal power units, wherein the equivalent The hourly operation and maintenance cost is equal to the ratio of the total maintenance cost to the equivalent operating time.

Further, in an embodiment of the present invention, the performance parameter is equal to the ratio of the actual total fuel consumption to the theoretical total fuel consumption, or equal to the ratio of the actual total heat input to the theoretical total heat input.

Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Description of drawings

The above and/or additional aspects and advantages of the present invention will become apparent and comprehensible from the description of the embodiments in conjunction with the following drawings, wherein:

Fig. 1 is the flow chart of the interval calculation method of marginal cost of power generation of a thermal power unit according to an embodiment of the present invention;

Fig. 2 is the flow chart of the interval calculation method of the marginal cost of power generation of the thermal power unit according to one embodiment of the present invention;

Fig. 3 is a schematic structural diagram of an interval calculation device for marginal cost of power generation of a thermal power unit according to an embodiment.

Detailed ways

Embodiments of the present invention are described in detail below, examples of which are shown in the drawings, wherein the same or similar reference numerals designate the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the figures are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, a feature defined as "first" and "second" may explicitly or implicitly include one or more of these features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

In the present invention, unless otherwise clearly specified and limited, terms such as "installation", "connection", "connection" and "fixation" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection , or integrally connected; it may be mechanically connected or electrically connected; it may be directly connected or indirectly connected through an intermediary, and it may be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention according to specific situations.

In the present invention, unless otherwise clearly specified and limited, a first feature being "on" or "under" a second feature may include direct contact between the first and second features, and may also include the first and second features Not in direct contact but through another characteristic contact between them. Moreover, "above", "above" and "above" the first feature on the second feature include that the first feature is directly above and obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature. "Below", "below" and "under" the first feature to the second feature include that the first feature is directly above and obliquely above the second feature, or simply means that the first feature is less horizontal than the second feature.

The method and device for calculating the marginal cost interval of thermal power generation according to the embodiments of the present invention will be described below with reference to the accompanying drawings. Referring to Figure 1, the accounting method includes the following steps:

S101. Obtain the marginal heat rate of the thermal power unit to obtain the marginal heat rate curve of the thermal power unit for power generation.

Further, in an embodiment of the present invention, the marginal heat rate is the heat input required to increase 1 MWh of electricity.

Specifically, in one embodiment of the present invention, as shown in FIG. 2, the implementation of the present invention includes:

S201, calculating the power generation marginal heat rate curve of the unit.

Among them, the heat consumption rate of the unit is equal to the ratio of the unit’s input heat to its output heat, and the unit is MBTU/MWh, as follows:

Marginal heat rate refers to the additional heat input required to increase 1MWh of electricity, as shown below. The marginal heat rate curve is a change curve formed by the marginal heat rate of the unit at different output levels.

Marginal heat rate = Δ input heat / 1MWh.

S102. Obtain performance parameters of power generation fuel consumption of the thermal power unit.

Further, in one embodiment of the present invention, the performance parameter is equal to the ratio of the actual total fuel consumption to the theoretical total fuel consumption or equal to the ratio of the actual total heat input to the theoretical total heat input.

Further, referring to Fig. 2, the embodiment of the present invention further includes:

S202, calculate the performance parameter of fuel consumption for power generation of the unit

Among them, the performance parameter of fuel consumption for power generation of the unit is equal to the ratio of the actual total fuel consumption to the theoretical total fuel consumption or equal to the ratio of the actual total heat input to the theoretical total heat input, as shown below. Relevant data can be obtained through periodic surveys to power plants.

S103. Obtain the fuel incremental cost of the thermal power unit according to the actual fuel price of the thermal power unit, the marginal heat rate curve of power generation and the performance parameters.

Further, in an embodiment of the present invention, the fuel incremental cost is obtained by multiplying the actual fuel price, the marginal heat rate curve of power generation and the performance parameter.

Further, referring to Fig. 2, the embodiment of the present invention further includes:

S203, read the actual fuel price (yuan/MBTU) used by the unit for power generation.

The power plant where the unit is located needs to provide a valid fuel purchase contract to market organizers, including information such as fuel source, purchase plan, negotiated price, transportation cost, and inventory cost.

S204. Calculate the fuel incremental cost of the power generation unit.

Among them, the fuel incremental cost of unit power generation (yuan/MWh) = actual fuel price (yuan/MBTU) x performance parameters of unit power generation fuel consumption × unit power generation marginal heat rate curve (MBTU/MWh).

S104. Obtain the no-load operation cost of the thermal power unit according to the actual fuel price, the heat to be input during no-load operation, and the performance parameters.

Further, referring to Fig. 2, the embodiment of the present invention further includes:

S205. Calculate the no-load operation cost of the unit.

Among them, the no-load cost of unit operation (yuan/h) = actual fuel price (yuan/MBTU) × heat input required for no-load operation of the unit (MBTU/h) × performance parameters of unit power generation fuel consumption.

S105, obtaining the average operation and maintenance cost of the thermal power unit.

Further, in one embodiment of the present invention, obtaining the average operation and maintenance cost of thermal power units further includes: obtaining the average operation and maintenance cost by averaging the equivalent hourly operation and maintenance costs of multiple thermal power units, wherein the equivalent hourly operation Maintenance cost is equal to the ratio of total maintenance cost to equivalent running time.

Further, referring to Fig. 2, the embodiment of the present invention further includes:

S206. Calculate the average operation and maintenance cost (yuan/h) of this type of generating set.

The equivalent hourly operation and maintenance cost of a unit is equal to the ratio of the total maintenance cost (yuan) to the equivalent operating time (h), as shown below. Relevant data can be obtained through periodic surveys to power plants.

The average operation and maintenance cost of this type of generating set can be obtained by calculating the average value of multiple generating sets.

S106. Obtain the marginal cost of the thermal power unit according to the output level, performance parameters, fuel incremental cost, average operation and maintenance cost, and no-load operation cost.

Further, referring to Fig. 2, the embodiment of the present invention further includes:

S207. Calculate the marginal cost (yuan/h) of generating electricity of the unit.

Among them, the marginal cost of unit power generation (yuan/h) = output level of the hour (MW) x performance parameters of unit power generation fuel consumption × fuel incremental cost of unit power generation (yuan/MWh) + average operation and maintenance cost of unit power generation ( Yuan/h).

S107. Calculating the range of the marginal cost of power generation of the thermal power unit according to the fluctuation range of the marginal cost and the operation and maintenance cost.

Further, referring to Fig. 2, the embodiment of the present invention further includes:

S208. Considering that the fluctuation interval of the operation and maintenance cost is [-σ, +σ], correspondingly calculate the interval of the marginal cost of power generation of the unit.

S209, end.

In the embodiment of the present invention, the embodiment of the present invention provides a powerful tool for the orderly operation and efficient supervision of the power spot market based on information such as the design parameters of the thermal power unit and the actual fuel price, fully considering the physical characteristics and technical characteristics of the thermal power unit operation Parameters, by verifying the source of fuel and its price and other relevant information submitted by the unit, to ensure the accuracy and rationality of the calculation of the marginal cost range of the unit for power generation, which is closely related to the actual operation of the power spot market, has strong applicability, and can be used as A functional module is embedded in the current links of market sorting, clearing, and market power testing. Its development is less difficult, more efficient, and has strong practicability.

It should be noted that the parameters and calculation formulas related to the power generation cost in the steps of the implementation of the present invention can be flexibly customized according to the data resources of the actual thermal power plant operation and business requirements, etc., and the scalability is strong. Therefore, those skilled in the art should understand that the above implementation steps are only used to illustrate rather than limit the technical solution of the present invention.

According to the interval calculation method for the marginal cost of thermal power generating units proposed in the embodiment of the present invention, the marginal cost of the thermal power unit is obtained through the output level, performance parameters, fuel incremental cost, average operation and maintenance cost, and no-load operating cost, so that according to the marginal cost and The fluctuation interval of operation and maintenance costs realizes the purpose of calculating the marginal cost interval of thermal power generation, fully considers the physical characteristics and technical parameters of thermal power unit operation, and improves the accuracy of accounting through the fuel price and other related information submitted by thermal power units, and It is closely related to the actual operation of the power spot market, has strong applicability and practicability, and is simple and convenient.

Next, with reference to the accompanying drawings, the device for calculating the marginal cost range of power generation of a thermal power unit according to an embodiment of the present invention will be described. 3, the accounting device 100 includes: a curve acquisition module 10, a performance parameter acquisition module 20, an incremental cost acquisition module 30, a no-load cost acquisition module 40, an average cost acquisition module 50, a marginal cost acquisition module 60 and a cost Interval acquisition module 70 .

Wherein, the curve obtaining module 10 is used to obtain the marginal heat rate of the thermal power unit to obtain the power generation marginal heat rate curve of the thermal power unit. The performance parameter acquisition module 20 is used to acquire the performance parameters of the power generation fuel consumption of the thermal power unit. The incremental cost acquisition module 30 is used to obtain the fuel incremental cost of the thermal power unit according to the actual fuel price of the thermal power unit, the marginal heat rate curve of power generation and performance parameters. The no-load cost acquisition module 40 is used to obtain the no-load operation cost of the thermal power unit according to the actual fuel price, the input heat and performance parameters during no-load operation. The average cost obtaining module 50 is used to obtain the average operation and maintenance cost of thermal power units. The marginal cost acquisition module 60 is used to obtain the marginal cost of the thermal power unit according to the output level, performance parameters, fuel incremental cost, average operation and maintenance cost and no-load operation cost. The cost range acquisition module 70 is used to calculate the marginal cost range of power generation of the thermal power unit according to the fluctuation range of the marginal cost and the operation and maintenance cost. The calculation device 100 of the embodiment of the present invention can calculate the marginal cost range of power generation of thermal power units through the fluctuation range of marginal cost and operation and maintenance cost, which improves the accuracy of calculation and has strong applicability and practicability.

Wherein, in one embodiment of the present invention, the marginal heat consumption rate is the heat that needs to be input when increasing 1 MWh of electricity.

Specifically, the heat rate of a unit is equal to the ratio of the unit's input heat to its output heat, and the unit is MBTU/MWh. The marginal heat rate refers to the additional heat input required to increase 1MWh of electricity. The marginal heat rate curve is a change curve formed by the marginal heat rate of the unit at different output levels.

Further, in an embodiment of the present invention, the incremental cost acquisition module 30 obtains the fuel incremental cost by multiplying the actual fuel price, the power generation marginal heat rate curve and the performance parameter.

Wherein, in the embodiment of the present invention, the fuel incremental cost can be obtained by multiplying the actual fuel price, the marginal heat rate curve of power generation and the performance parameter.

Specifically, incremental fuel cost of unit power generation (yuan/MWh) = actual fuel price (yuan/MBTU) x performance parameters of unit power generation fuel consumption x unit power generation marginal heat rate curve (MBTU/MWh).

Further, in one embodiment of the present invention, the average cost acquisition module 50 is specifically used to obtain the average operation and maintenance cost by averaging the equivalent hourly operation and maintenance costs of multiple thermal power units, wherein the equivalent hourly operation and maintenance cost is equal to Ratio of total maintenance cost to equivalent operating time.

Among them, the equivalent hourly operation and maintenance cost of a unit is equal to the ratio of the total maintenance cost (yuan) to the equivalent operating time (h). Relevant data can be obtained through periodic surveys to power plants. The average operation and maintenance cost of this type of generating set can be obtained by calculating the average value of multiple generating sets.

Further, in one embodiment of the present invention, the performance parameter is equal to the ratio of the actual total fuel consumption to the theoretical total fuel consumption or equal to the ratio of the actual total heat input to the theoretical total heat input.

Further, in an embodiment of the present invention, the no-load cost of unit operation (yuan/h) = actual fuel price (yuan/MBTU) x heat input required for unit no-load operation (MBTU/h) x unit power generation Performance parameters of fuel consumption.

Further, in one embodiment of the present invention, the marginal cost of unit power generation (yuan/h)=the output level of the hour (MW)×the performance parameter of unit power generation fuel consumption×the fuel incremental cost of unit power generation (yuan/MWh ) + the average operation and maintenance cost of generating units (yuan/h).

It should be noted that the specific implementation manner of the apparatus in the embodiment of the present invention is similar to the specific implementation manner of the method part, and details are not described here to reduce redundancy.

According to the thermal power generation marginal cost interval calculation device proposed in the embodiment of the present invention, the marginal cost of the thermal power unit is obtained through the output level, performance parameters, fuel incremental cost, average operation and maintenance cost, and no-load operation cost, thereby according to the marginal cost and The fluctuation interval of operation and maintenance costs realizes the purpose of calculating the marginal cost interval of thermal power generation, fully considers the physical characteristics and technical parameters of thermal power unit operation, and improves the accuracy of accounting through the fuel price and other related information submitted by thermal power units, and It is closely related to the actual operation of the power spot market, has strong applicability and practicability, and is simple and convenient.

Any process or method descriptions in flowcharts or otherwise described herein may be understood to represent modules, segments or portions of code comprising one or more executable instructions for implementing specific logical functions or steps of the process , and the scope of preferred embodiments of the invention includes alternative implementations in which functions may be performed out of the order shown or discussed, including substantially concurrently or in reverse order depending on the functions involved, which shall It is understood by those skilled in the art to which the embodiments of the present invention pertain.

The logic and/or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a sequenced listing of executable instructions for implementing logical functions, can be embodied in any computer-readable medium, For use with instruction execution systems, devices, or devices (such as computer-based systems, systems including processors, or other systems that can fetch instructions from instruction execution systems, devices, or devices and execute instructions), or in conjunction with these instruction execution systems, devices or equipment for use. For the purposes of this specification, a "computer-readable medium" may be any device that can contain, store, communicate, propagate or transmit a program for use in or in conjunction with an instruction execution system, device or device. More specific examples (non-exhaustive list) of computer-readable media include the following: electrical connection with one or more wires (electronic device), portable computer disk case (magnetic device), random access memory (RAM), Read Only Memory (ROM), Erasable and Editable Read Only Memory (EPROM or Flash Memory), Fiber Optic Devices, and Portable Compact Disc Read Only Memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program can be printed, since the program can be read, for example, by optically scanning the paper or other medium, followed by editing, interpretation or other suitable processing if necessary. The program is processed electronically and stored in computer memory.

It should be understood that various parts of the present invention can be realized by hardware, software, firmware or their combination. In the embodiments described above, various steps or methods may be implemented by software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented by any one or combination of the following techniques known in the art: Discrete logic circuits, ASICs with suitable combinational logic gates, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), etc.

Those of ordinary skill in the art can understand that all or part of the steps carried by the methods of the above embodiments can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium. During execution, one or a combination of the steps of the method embodiments is included.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing module, each unit may exist separately physically, or two or more units may be integrated into one module. The above-mentioned integrated modules can be implemented in the form of hardware or in the form of software function modules. If the integrated modules are realized in the form of software function modules and sold or used as independent products, they can also be stored in a computer-readable storage medium.

The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, and the like.

In the description of this specification, descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific examples", or "some examples" mean that specific features described in connection with the embodiment or example , structure, material or characteristic is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be construed as limitations to the present invention. Variations, modifications, substitutions, and modifications to the above-described embodiments are possible within the scope of the present invention.

Claims (10)

1. a method for calculating the marginal cost interval of thermal power generation unit, is characterized in that, comprises the following steps: Obtaining the marginal heat rate of the thermal power unit to obtain the marginal heat rate curve for power generation of the thermal power unit; Acquiring performance parameters of fuel consumption for power generation of the thermal power unit; Obtaining the fuel incremental cost of the thermal power unit according to the actual fuel price of the thermal power unit, the marginal heat rate curve for power generation and the performance parameters; Obtaining the no-load operation cost of the thermal power unit according to the actual fuel price, the heat input during the no-load operation and the performance parameters; Obtain the average operation and maintenance cost of the thermal power unit; Obtaining the marginal cost of the thermal power unit according to the output level, the performance parameter, the fuel incremental cost, the average operation and maintenance cost and the no-load operation cost; and Calculating the range of the marginal cost of power generation of the thermal power unit according to the fluctuation range of the marginal cost and the operation and maintenance cost. 2. The interval calculation method for the marginal cost of power generation of a thermal power unit according to claim 1, wherein the marginal heat rate is the amount of heat that needs to be input when increasing 1MWh of electricity. 3. The interval calculation method of the marginal cost of power generation of thermal power units according to claim 1, characterized in that, the fuel increase is obtained by multiplying the actual fuel price, the marginal heat rate curve of power generation and the performance parameter. volume cost. 4. The interval calculation method of the marginal cost of power generation of the thermal power unit according to claim 1, wherein said obtaining the average operation and maintenance cost of the thermal power unit further comprises: The average operation and maintenance cost is obtained by averaging the equivalent hourly operation and maintenance costs of multiple thermal power units, wherein the equivalent hourly operation and maintenance cost is equal to the ratio of the total maintenance cost to the equivalent operating time. 5. The interval calculation method of marginal cost of power generation of thermal power unit according to claim 1, characterized in that, said performance parameter is equal to the actual consumption of total fuel and theoretical consumption of total fuel banknotes or equal to the total heat of actual need input and theoretical need input ratio of total heat. 6. A power generation marginal cost interval accounting device for a thermal power unit, characterized in that it comprises: A curve acquisition module, configured to obtain the marginal heat rate of the thermal power unit to obtain the marginal heat rate curve for power generation of the thermal power unit; A performance parameter acquisition module, configured to acquire the performance parameters of the power generation fuel consumption of the thermal power unit; An incremental cost acquisition module, configured to obtain the fuel incremental cost of the thermal power unit according to the actual fuel price of the thermal power unit, the marginal heat rate curve for power generation, and the performance parameters; The no-load cost acquisition module is used to obtain the no-load operation cost of the thermal power unit according to the actual fuel price, the heat to be input during no-load operation and the performance parameters; The average cost acquisition module is used to obtain the average operation and maintenance cost of the thermal power unit; A marginal cost acquisition module, configured to obtain the marginal cost of the thermal power unit according to the output level, the performance parameters, the fuel incremental cost, the average operation and maintenance cost, and the no-load operation cost; and A cost range acquisition module, configured to calculate the marginal cost range of power generation of the thermal power unit according to the fluctuation range of the marginal cost and the operation and maintenance cost. 7. The interval calculation device for the marginal cost of power generation of a thermal power unit according to claim 6, wherein the marginal heat rate is the heat that needs to be input when increasing 1MWh of electricity. 8. The interval calculation device for the marginal cost of power generation of thermal power units according to claim 6, wherein the incremental cost acquisition module passes the actual fuel price, the marginal heat rate curve of the power generation and the performance parameter Multiply to get the fuel incremental cost. 9. The interval calculation device for marginal cost of power generation of thermal power units according to claim 6, wherein the average cost acquisition module is specifically used to obtain the average value of the equivalent hourly operation and maintenance costs of a plurality of thermal power units. The average operation and maintenance cost, wherein, the equivalent hourly operation and maintenance cost is equal to the ratio of the total maintenance cost to the equivalent operation time. 10. The generation marginal cost interval accounting device of thermal power unit according to claim 6, characterized in that, said performance parameter is equal to the actual consumption of total fuel and theoretical consumption of total fuel banknotes or equal to the total heat of actual need input and theoretical need input ratio of total heat.