Steam heat accumulator check analysis method

Abstract

The invention relates to a check analysis method for a steam heat accumulator. The method comprises the steps that inlet and outlet parameters and design parameters of the heat accumulator are set; calculating inlet and outlet steam enthalpy values, densities and saturation parameters under corresponding pressures; calculating the volume of water in the heat accumulator when the heat accumulator is fully filled with heat and the volume of water in the heat accumulator when the heat accumulator is fully released; the pressure in the heat accumulator at the starting time, the time interval and the ending time are set; the water amount, the steam amount and the total energy in the heat accumulator at the initial time are calculated; the mass change and the energy change of the heat accumulator at the current time step are calculated; calculating the water quantity change, the steam quantity change, the water quantity, the steam quantity, the internal pressure and the total energy of the heat accumulator in all time steps; if the internal pressure of the heat accumulator is greater than the highest internal pressure of the heat accumulator, triggering pressure overrun drainage and recalculating the parameters; and if the internal pressure of the heat accumulator is smaller than the lowest internal pressure of the heat accumulator, overheat release correction is triggered, and the parameters are recalculated. According to the invention, matching of different hourly inlet and outlet parameters and heat accumulator thermal performance checking under abnormal working conditions can be realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of heat exchange equipment and relates to a method for checking and analyzing a steam accumulator. Background Art

[0003] An accumulator is a device used to balance short-term peak loads. It stores thermal energy when steam supply is sufficient or the cost is low, and releases thermal energy during peak demand or insufficient supply, thereby balancing the supply-demand difference, improving energy utilization efficiency and system flexibility. The basic principle of a steam accumulator is to use water as the heat storage medium. When there is surplus steam, the steam is introduced into the accumulator, contacts the water in the container and heats the water to the saturated state. The remaining part may remain in the gaseous state and be stored in the upper part of the container. At this time, the saturated water level in the accumulator rises, the internal pressure increases, and the temperature increases. When the inlet steam supply is insufficient, the saturated water stored in the accumulator evaporates into saturated steam to compensate for the demand for the outlet steam volume. The saturated water level drops, the internal pressure in the accumulator drops, and the temperature of the accumulator drops.

[0004] Currently, the thermal calculation of steam accumulators generally adopts the thermal calculation method of accumulators given in "Oxygen Top-Blown Converter Evaporative Cooling Design". This method determines the required heat storage volume of the accumulator by the difference between the highest and lowest values of the integral of the typical load curve. However, this method is mainly used for design calculations and cannot reflect the hourly changes in the water volume, steam volume, and energy of the accumulator. When the actual operating load curve differs greatly from the typical load curve selected during design, the accumulator may have a volume mismatch, resulting in overpressure drainage or overheat shutdown of the accumulator, causing a large amount of energy waste and affecting the stability of the outlet steam. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a method for checking and analyzing a steam accumulator to solve the problem of hourly thermal performance checking and calculation of current steam accumulators.

[0006] To achieve the above purpose, the present invention provides the following technical solutions:

[0007] A method for checking and analyzing a steam accumulator includes the following steps:

[0008] S1: Obtain the hourly inlet flow rate and hourly outlet flow rate of the accumulator to be checked, as well as the inlet steam pressure, inlet steam temperature, outlet steam pressure, outlet steam superheat degree, accumulator volume, water filling coefficient, thermal efficiency, maximum internal pressure of the accumulator, and minimum internal pressure of the accumulator;

[0009] S2: Calculate the enthalpy values and densities of the inlet and outlet steam, as well as the saturated water / steam temperatures, enthalpies, and densities at the corresponding pressures based on the parameters obtained in step S1;

[0010] S3: Calculate the water volume in the heat accumulator when it is full of heat and the water volume in the heat accumulator when it is completely discharged according to the volume of the heat accumulator, the water filling coefficient, the thermal efficiency, the maximum internal pressure of the heat accumulator, and the minimum internal pressure of the heat accumulator;

[0011] S4: Set the internal pressure of the heat accumulator at the start time, the calculation time interval, and the calculation end time;

[0012] S5: Calculate the water quantity, steam quantity, and total energy in the heat accumulator at the initial time according to the internal pressure of the heat accumulator at the initial time. The calculation of the initial time step is completed;

[0013] S6: Calculate the mass change and energy change of the heat accumulator at the current time step according to the inlet and outlet flow rates, enthalpy values, time interval, and the calculation results of the previous time step;

[0014] S7: Calculate the water quantity change, steam quantity change, and the water quantity, steam quantity, internal pressure, and total energy of the current heat accumulator at the current time step according to the steam-water balance equation and the gas state equation;

[0015] S8: If the internal pressure of the heat accumulator calculated in S7 is greater than the maximum internal pressure of the heat accumulator, the heat accumulator triggers pressure overlimit drainage, and recalculate the water quantity change, steam quantity change, and the water quantity, steam quantity, drainage volume, drainage energy loss, internal pressure, and total energy of the current heat accumulator at the current time step according to the steam-water balance equation and the gas state equation;

[0016] If the internal pressure of the heat accumulator calculated in S7 is less than the minimum internal pressure of the heat accumulator, the heat accumulator triggers overheat release correction, and recalculate the water quantity change, steam quantity change, and the water quantity, steam quantity, outlet flow rate, internal pressure, and total energy of the current heat accumulator at the current time step according to the steam-water balance equation and the gas state equation;

[0017] S9: The calculation of the current time step is completed, return to S6 to calculate the next time step until the current time step reaches the calculation end time. Further, in step S2, the enthalpy value, density state equations of superheated steam, saturated steam, and saturated water are:

[0018] [h,ρ] supervapor =f(T,P)

[0019] [h,ρ] saturated =f(P)

[0020] where h is the enthalpy value, ρ is the density, T is the temperature, P is the pressure, f(T,P) represents the calculation state equation of the enthalpy value and density of superheated steam, and f(P) represents the calculation state equation of the enthalpy value and density of saturated steam / water.

[0021] Further, the calculation formula for the water volume in the heat accumulator when it is full of heat in step S3 is:

[0022] V1 = ηψVtot

[0023] The calculation formula for the volume of water in the heat storage tank when it is completely exothermic is:

[0024] V2 = (ρ 1,satwater V1 - g0V1) / ρ 2,satwater

[0025] Among them, η is the heat efficiency of the heat storage tank, ψ is the water filling coefficient of the heat storage tank, ρ 1,satwater is the saturated water density corresponding to the highest internal pressure P1 of the heat storage tank. The water volume of the heat storage tank at the internal pressure P1 is V1, g0 is the unit heat storage capacity of the heat storage tank, ρ 2,satwater is the saturated water density corresponding to the lowest internal pressure P2 of the heat storage tank. The water volume of the heat storage tank at the internal pressure P2 is V2.

[0026] Furthermore, in step S6, the equations for the mass change and energy change of the heat storage tank at time step k are:

[0027] M tot,k = M tot,k-1 + Δt(G in,k - G out,k )

[0028] Q tot,k = Q tot,k-1 + Δt(q in,k - q out,k )

[0029] Among them, M is the mass, Q is the energy, Δt is the calculation time interval, G in,k is the flow rate entering the heat storage tank at time step k, G out,k is the flow rate leaving the heat storage tank at time step k, q in,k is the heat power entering the heat storage tank, q out,k is the heat power leaving the heat storage tank.

[0030] Furthermore, in step S7, the equations for the water volume, steam volume, internal pressure, and total energy of the heat storage tank at time step k are:

[0031] V tot = V water,k + V vapor,k

[0032] M vapor,k = ρ satvapor,k V vapor,k

[0033] M tot,k = M water,k + M vapor,k

[0034] Q tot,k = Qwater,k +Q vapor,k = M water,k h water,k +M vapor,k h vapor,k

[0035] P k = f(ρ satvapor )

[0036] wherein, V is the volume, ρ satvapor,k is the density of saturated steam in the heat accumulator at time step k, P k is the pressure in the heat accumulator at time step k, f(ρ satvapor,k ) represents the calculated state equation of the saturated steam pressure.

[0037] Furthermore, in step S8, when the heat accumulator triggers drainage, the flow rate G out,k leaving the heat accumulator and the heat power q out,k leaving the heat accumulator at time step k should include the drainage flow rate and the heat power carried away by the drainage. The drainage flow rate value is determined by maintaining the pressure in the heat accumulator at time step k as the highest internal pressure of the heat accumulator.

[0038] Furthermore, in step S8, when the heat accumulator triggers overheat release correction, the flow rate G out,k leaving the heat accumulator and the heat power q out,k leaving the heat accumulator at time step k are re-determined by maintaining the pressure in the heat accumulator as the lowest internal pressure of the heat accumulator.

[0039] Furthermore, for the heat accumulator that outputs saturated steam, the superheat degree of the outlet steam is equal to 0, and the outlet steam temperature is the saturated temperature corresponding to the outlet steam pressure; for the heat accumulator that outputs superheated steam, the superheat degree and the outlet pressure of the outlet steam are determined by the parameters of the outlet Laval nozzle, throttle valve, and superheater, and the outlet steam temperature is the saturated temperature corresponding to the outlet steam pressure plus the superheat degree of the outlet steam.

[0040] Furthermore, the system of equations of each variable at time step k is solved by the iterative method. First, assume that the water volume in the heat accumulator is M set . Based on this, calculate the steam volume, internal pressure, and total energy in the heat accumulator. Compare the total energy obtained by assuming the water volume with the total energy obtained through step S6. If the error is less than the set value, the iteration is completed; otherwise, adjust the assumed water volume M set and recalculate.

[0041] Further, after the check calculation of the heat accumulator is completed, count the cases of overpressure drainage and overheat release correction of the heat accumulator during the entire calculation period. According to the allowable drainage volume and overheat release amount of the heat accumulator and a certain safety margin, determine whether the checked heat accumulator meets the operation requirements; if not, adjust the hourly outlet flow rate, heat accumulator volume, maximum internal pressure of the heat accumulator, minimum internal pressure of the heat accumulator, outlet steam superheat degree, water filling coefficient, and thermal efficiency, and re-perform the check calculation of the heat accumulator until the operation requirements are met.

[0042] The beneficial effects of the present invention are as follows:

[0043] 1. The present invention provides a check analysis method for a steam heat accumulator, which can realize the check calculation of the thermal performance of the heat accumulator, and provide a guiding basis for the safe and energy-saving operation of the heat accumulator and the improvement of the heat accumulator operation;

[0044] 2. The check analysis method provided by the present invention adopts the hourly flow calculation design, and can obtain the water volume and energy change of the heat accumulator at each time step, with higher accuracy compared with the traditional method;

[0045] 3. The check analysis method provided by the present invention gives the calculation methods under two abnormal conditions of overpressure drainage and overheat release correction of the heat accumulator, and realizes the reliable evaluation of the time points and operation states of abnormal conditions.

[0046] Other advantages, objectives, and features of the present invention will be described to some extent in the subsequent description, and to some extent, will be obvious to those skilled in the art based on the study of the following text, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. Description of the Drawings

[0047] In order to make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be described in detail preferably with reference to the drawings, where:

[0048] Figure 1 is a flow chart of a check analysis method for a steam heat accumulator of the present invention;

[0049] Figure 2 is a diagram of the hourly inlet and outlet flow rates of the heat accumulator in an embodiment of the present invention;

[0050] Figure 3 is a diagram of the hourly drainage volume of the heat accumulator in an embodiment of the present invention. Detailed Embodiments

[0051] The following specific examples are used to illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0052] It should be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner. Therefore, only the components related to the present invention are shown in the diagrams, rather than being drawn according to the number, shape, and size of the components in actual implementation. The types, quantities, and ratios of the components in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0053] In the following description, a large number of details are explored to provide a more thorough explanation of the embodiments of the present invention. However, it is obvious to those skilled in the art that the embodiments of the present invention can be implemented without these specific details. In other embodiments, well-known structures and devices are shown in the form of block diagrams rather than in detail to avoid making the embodiments of the present invention difficult to understand.

[0054] As Figure 1 shown, the present invention provides a method for checking and analyzing a steam accumulator, including the following steps:

[0055] S1. It is necessary to check the hourly inlet flow rate and hourly outlet flow rate of the accumulator. As Figure 2 shown, the inlet steam pressure is 1.8 Mpa, the inlet steam temperature is 207.11 °C, the outlet steam pressure is 1.0 Mpa, the outlet steam superheat degree is 12 °C, the volume of the accumulator is 1300 m 3 , the water filling coefficient is 0.80, the thermal efficiency is 0.99, the maximum internal pressure of the accumulator is 1.6 Mpa, and the minimum internal pressure of the accumulator is 1.0 Mpa; for the accumulator that outputs superheated steam, the outlet steam superheat degree and outlet pressure are determined by the parameters of the outlet Laval nozzle, throttle valve, and superheater. The outlet steam temperature is the saturation temperature corresponding to the outlet steam pressure plus the outlet steam superheat degree.

[0056] S2. Calculate the enthalpy values, densities of the inlet and outlet steam, as well as the saturation water / steam temperatures, enthalpies, and densities at the corresponding pressures according to the inlet and outlet parameters. The state equations of the enthalpy values and densities of superheated steam, saturated steam, and saturated water are

[0057] [h,ρ] supervapor = f(T,P)

[0058] [h,ρ] saturated = f(P)

[0059] Among them, h is the enthalpy value, ρ is the density, T is the temperature, P is the pressure, f(T, P) represents the calculation state equation of the enthalpy value and density of superheated steam, and f(P) represents the calculation state equation of the enthalpy value and density of saturated steam / water. The above state equations are solved using the IAPWS-1995 standard.

[0060] S3. Calculate the water volume in the accumulator when it is full of heat and the water volume in the accumulator when it is completely discharging heat according to the accumulator volume, water filling coefficient, thermal efficiency, maximum internal pressure of the accumulator, and minimum internal pressure of the accumulator. The calculation formula for the water volume in the accumulator when it is full of heat is

[0061] V1 = ηψV tot

[0062] The calculation formula for the water volume in the accumulator when it is completely discharging heat is

[0063] V2 = (ρ 1,satwater V1 - g0V1) / ρ 2,satwater

[0064] Among them, η is the thermal efficiency of the accumulator, ψ is the water filling coefficient of the accumulator, ρ 1,satwater is the saturated water density corresponding to the maximum internal pressure P1 of the accumulator. The water volume of the accumulator at the internal pressure P1 is V1, g0 is the unit heat storage capacity of the accumulator, ρ 2,satwater is the saturated water density corresponding to the minimum internal pressure P2 of the accumulator. The water volume of the accumulator at the internal pressure P2 is V2.

[0065] S4. Set the internal pressure of the accumulator at the starting time to 1.24 Mpa, the calculation time interval Δt = 1 min, and the calculation end time to 75 min;

[0066] S5. Calculate the water quantity, steam quantity, and total energy in the accumulator at the initial time according to the internal pressure of the accumulator at the initial time. The calculation of the initial time step is completed;

[0067] S6. Calculate the mass change and energy change of the accumulator at the current time step according to the inlet and outlet flow rates, enthalpy values, time interval, and the calculation results of the previous time step. Directly solve the equations for the mass change and energy change of the accumulator at the following time step k:

[0068] M tot,k = M tot,k-1 + Δt(G in,k - G out,k )

[0069] Q tot,k = Q tot,k-1 + Δt(qin,k -q out,k )

[0070] where M is the mass, Q is the energy, Δt is the calculation time interval, G in,k is the flow rate into the heat accumulator at time step k, G out,k is the flow rate out of the heat accumulator at time step k, q in,k is the heat power into the heat accumulator, q out,k is the heat power out of the heat accumulator.

[0071] S7. Calculate the change in the water volume, steam volume, water volume, steam volume, internal pressure, and total energy of the heat accumulator at the current time step according to the steam-water balance equation and the gas state equation. Solve the equations for the water volume, steam volume, internal pressure, and total energy of the heat accumulator at the following time step k by the iterative method:

[0072] V tot = V water,k + V vapor,k

[0073] M vapor,k = ρ satvapor,k V vapor,k

[0074] M tot,k = M water,k + M vapor,k

[0075] Q tot,k = Q water,k + Q vapor,k = M water,k h water,k + M vapor,k h vapor,k

[0076] P k = f(ρ satvapor )

[0077] where V is the volume, ρ satvapor,k is the density of saturated steam in the heat accumulator at time step k, P k is the internal pressure in the heat accumulator at time step k, f(ρ satvapor,k ) represents the calculation state equation of the saturated steam pressure, and the state equation is solved according to the IAPWS-1995 standard. When solving the above equations by the iterative method, first assume that the water volume of the heat accumulator is M set , calculate the steam volume, internal pressure, and total energy of the heat accumulator based on this, compare the total energy calculated by the assumed water volume with the total energy calculated by S6. If the error is less than the set value, the iteration is completed; otherwise, adjust the assumed water volume M set and recalculate.

[0078] S8. If the pressure in the heat accumulator calculated in S7 is greater than the maximum internal pressure of the heat accumulator, the heat accumulator triggers pressure overlimit drainage, and recalculates the change in the water volume, steam volume, and the current water volume, steam volume, drainage volume, drainage energy loss, internal pressure, and total energy of the heat accumulator at the current time step according to the steam-water balance equation and the gas state equation. And the flow rate G leaving the heat accumulator at time step k out,k and the heat power q leaving the heat accumulator out,k should include the drainage flow rate and the heat power carried away by the drainage. The drainage flow rate value is determined by keeping the pressure in the heat accumulator at the maximum internal pressure of the heat accumulator at time step k.

[0079] If the pressure in the heat accumulator calculated in S7 is less than the minimum internal pressure of the heat accumulator, the heat accumulator triggers overheat release correction, and recalculates the change in the water volume, steam volume, and the current water volume, steam volume, outlet flow rate, internal pressure, and total energy of the heat accumulator at the current time step according to the steam-water balance equation and the gas state equation. And the flow rate G leaving the heat accumulator at time step k out,k and the heat power q leaving the heat accumulator out,k should be re-determined by keeping the pressure in the heat accumulator at the minimum internal pressure of the heat accumulator.

[0080] For the heat accumulator that outputs saturated steam, the superheat degree of the outlet steam is equal to 0, and the outlet steam temperature is the saturated temperature corresponding to the outlet steam pressure; for the heat accumulator that outputs superheated steam, the superheat degree of the outlet steam and the outlet pressure are determined by the parameters of the outlet Laval nozzle, throttle valve, and superheater, and the outlet steam temperature is the saturated temperature corresponding to the outlet steam pressure plus the superheat degree of the outlet steam.

[0081] S9. After the calculation of the current time step is completed, return to S6 to calculate the next time step k = k + 1 until the current time step k reaches the calculation end time of 75 min.

[0082] After the verification calculation of the heat accumulator is completed, count the pressure overlimit drainage of the heat accumulator during the entire calculation period as Figure 3 shown. Drainage occurred at 34 - 39 min, with a total drainage of 13.6 tons and an energy loss of 38860 MJ; no overheat release occurred during the calculation period; according to the allowable drainage volume and overheat release amount of the heat accumulator and a certain safety margin, this heat accumulator does not meet the operation requirements, and the design parameters such as the hourly outlet flow rate, heat accumulator volume, maximum internal pressure of the heat accumulator, minimum internal pressure of the heat accumulator, superheat degree of the outlet steam, water filling coefficient, and thermal efficiency should be adjusted, and the verification calculation of the heat accumulator should be carried out again until the operation requirements are met.

[0083] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the present technical solution, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A method for checking and analyzing a steam accumulator, characterized in that: It includes the following steps: S1: Obtain the hourly inlet flow rate and hourly outlet flow rate of the heat accumulator to be checked, as well as the inlet steam pressure, inlet steam temperature, outlet steam pressure, outlet steam superheat degree, heat accumulator volume, water filling coefficient, thermal efficiency, maximum internal pressure of the heat accumulator, and minimum internal pressure of the heat accumulator; S2: Calculate the enthalpy values and densities of the inlet and outlet steam, as well as the saturated water / steam temperature, enthalpy, and density at the corresponding pressures based on the parameters obtained in step S1; S3: Calculate the volume of water in the heat accumulator when it is full of heat and the volume of water in the heat accumulator when it is completely discharged based on the heat accumulator volume, water filling coefficient, thermal efficiency, maximum internal pressure of the heat accumulator, and minimum internal pressure of the heat accumulator; S4: Set the internal pressure of the heat accumulator at the starting time, the calculation time interval, and the calculation end time; S5: Calculate the water volume, steam volume, and total energy in the heat accumulator at the initial time based on the internal pressure of the heat accumulator at the initial time. The calculation of the initial time step is completed; S6: Calculate the mass change and energy change of the heat accumulator at the current time step based on the inlet and outlet flow rates, enthalpy values, time interval, and the calculation results of the previous time step; S7: Calculate the water volume change, steam volume change, and the water volume, steam volume, internal pressure, and total energy of the current heat accumulator at the current time step according to the steam-water balance equation and the gas state equation; S8: If the internal pressure of the heat accumulator calculated in S7 is greater than the maximum internal pressure of the heat accumulator, the heat accumulator triggers pressure overlimit drainage, and recalculate the water volume change, steam volume change, and the water volume, steam volume, drainage volume, drainage energy loss, internal pressure, and total energy of the current heat accumulator at the current time step according to the steam-water balance equation and the gas state equation; If the internal pressure of the heat accumulator calculated in S7 is less than the minimum internal pressure of the heat accumulator, the heat accumulator triggers overheat release correction, and recalculate the water volume change, steam volume change, and the water volume, steam volume, outlet flow rate, internal pressure, and total energy of the current heat accumulator at the current time step according to the steam-water balance equation and the gas state equation; S9: After the calculation of the current time step is completed, return to S6 to calculate the next time step until the current time step reaches the calculation end time.

2. The steam accumulator checking and analyzing method according to claim 1, characterized in that: In step S2, the state equations for the enthalpy values and densities of superheated steam, saturated steam, and saturated water are: [h, ρ] supervapor = f(T, P) [h, ρ] saturated = f(P) Where, h is the enthalpy value, ρ is the density, T is the temperature, P is the pressure, f(T,P) represents the calculation state equation for the enthalpy value and density of superheated steam, and f(P) represents the calculation state equation for the enthalpy value and density of saturated steam / water.

3. The steam accumulator checking and analyzing method according to claim 1, characterized in that: The calculation formula for the volume of water in the heat accumulator when it is full of heat described in step S3 is: V1 = ηψV tot The calculation formula for the volume of water in the heat accumulator when it is completely discharged is: V2 = (ρ 1,satwater V1 - g0V1) / ρ 2,satwater Among them, η is the thermal efficiency of the heat accumulator, ψ is the water filling coefficient of the heat accumulator, ρ 1,satwater is the saturated water density corresponding to the highest internal pressure P1 of the heat accumulator. When the internal pressure is P1, the water volume of the heat accumulator is V1, g0 is the unit heat storage capacity of the heat accumulator, ρ 2,satwater is the saturated water density corresponding to the lowest internal pressure P2 of the heat accumulator. When the internal pressure is P2, the water volume of the heat accumulator is V2.

4. The steam accumulator checking and analysis method according to claim 1, characterized in that: In step S6, the equations for the mass change and energy change of the heat accumulator at time step k are: M tot,k = M tot,k-1 + Δt(G in,k - G out,k ) Q tot,k = Q tot,k-1 + Δt(q in,k - q out,k ) where M is the mass, Q is the energy, Δt is the calculation time interval, G in,k is the flow rate entering the heat accumulator at time step k, G out,k is the flow rate leaving the heat accumulator at time step k, q in,k is the heat power entering the heat accumulator, q out,k is the heat power leaving the heat accumulator.

5. The steam accumulator checking and analysis method according to claim 4, characterized in that: In step S7, the equations for the water volume, steam volume, internal pressure, and total energy of the heat accumulator at time step k are: V tot = V water,k + V vapor,k M vapor,k = ρ satvapor,k V vapor,k M tot,k = M water,k + M vapor,k Q tot,k = Q water,k + Q vapor,k = M water,k h water,k + M vapor,k h vapor,k P k = f(ρ satvapor ) where V is the volume, ρ satvapor,k is the density of saturated steam in the heat accumulator at time step k, P k is the pressure in the heat accumulator at time step k, and f(ρ satvapor,k ) represents the calculated state equation of the saturated steam pressure.

6. The steam accumulator checking and analyzing method according to claim 1, characterized in that: In step S8, when the heat accumulator triggers drainage, the flow rate G of the time step k leaving the heat accumulator out,k and the heat power q leaving the heat accumulator out,k shall include the drainage flow rate and the heat power carried away by the drainage. The drainage flow rate value is determined by maintaining the pressure in the heat accumulator at the highest internal pressure of the heat accumulator for the time step k.

7. The checking and analyzing method of the steam accumulator according to claim 1, characterized in that: In step S8, when the heat accumulator triggers overheat release correction, the flow rate G of the time step k leaving the heat accumulator out,k and the heat power q leaving the heat accumulator out,k are re-determined according to maintaining the pressure in the heat accumulator at the lowest internal pressure of the heat accumulator.

8. The steam accumulator checking and analysis method according to claim 1, characterized in that: For a heat accumulator that outputs saturated steam, the outlet steam superheat degree is equal to 0, and the outlet steam temperature is the saturated temperature corresponding to the outlet steam pressure; for a heat accumulator that outputs superheated steam, the outlet steam superheat degree and outlet pressure are determined by the parameters of the outlet Laval nozzle, throttle valve, and superheater, and the outlet steam temperature is the saturated temperature corresponding to the outlet steam pressure plus the outlet steam superheat degree.

9. The steam accumulator checking and analyzing method according to claim 5, wherein: The system of equations for each variable at time step k is solved by an iterative method. First, assume that the water volume in the heat accumulator is M set , and based on this, calculate the steam volume, internal pressure, and total energy in the heat accumulator. Compare the total energy calculated by the assumed water volume with the total energy calculated in step S6. If the error is less than the set value, the iteration is completed; otherwise, adjust the assumed water volume M in the heat accumulator set Recalculate.

10. The steam accumulator checking and analysis method according to claim 1, characterized in that: After the check calculation of the heat accumulator is completed, count the situation of over-limit drainage of the heat accumulator pressure and overheat release correction during the entire calculation period. According to the allowable drainage volume and overheat release amount of the heat accumulator and a certain safety margin, determine whether the checked heat accumulator meets the operation requirements; if not, adjust the hourly outlet flow rate, heat accumulator volume, maximum internal pressure of the heat accumulator, minimum internal pressure of the heat accumulator, outlet steam superheat degree, water filling coefficient, and thermal efficiency, and re-perform the check calculation of the heat accumulator until the operation requirements are met.

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