Method and system for judging influence of transient process system frequency change on thermal effect of thermal power generating unit

Abstract

The invention discloses a method for judging the influence of transient process system frequency change on the thermal effect of a thermal power generating unit. The method comprises the steps of obtaining data information of a target on the thermal power generating unit; constructing a turbine-speed regulator typical model of the target thermal power generating unit; calculating to obtain main steam flow data input by a steam turbine of the target thermal power generating unit; calculating by combining a turbine-speed regulator typical model to obtain parameter information after the heat effect of the boiler is considered; calculating to obtain a heat effect evaluation index and a system frequency safety margin index of the target thermal power generating unit; and calculating to obtain a thermal effect frequency response index of the target thermal power generating unit and judging the influence of the transient process system frequency change on the thermal effect of the target thermal power generating unit. The invention also discloses a system for realizing the method for judging the influence of the transient process system frequency change on the thermal effect of the thermal power generating unit. According to the method, the influence of the transient process system frequency change on the thermal effect of the thermal power generating unit is judged, the reliability is higher, and the accuracy is better.

Description

Technical Field

[0001] The present invention belongs to the field of electrical automation, and particularly relates to a method and system for determining the influence of the frequency change of a transient process system on the thermal effect of a thermal power unit. Background Art

[0002] With the development of economic technology and the improvement of people's living standards, electric energy has become an essential secondary energy source in people's production and life, bringing endless convenience to people's production and life. Therefore, ensuring the stable and reliable supply of electric energy has become one of the most important tasks of the power system.

[0003] The electromechanical transient simulation analysis of the power system is of great significance to the power system. Currently, the commonly used transient simulation software for the power system is PSS / E software, which provides an application program interface (API) based on Python, providing a data exchange channel between Python and PSS / E. Through the API, functions can be directly called to implement the parameter configuration of PSS / E and control PSS / E to realize functions such as power flow calculation and transient simulation.

[0004] At the present stage, with the change of the power system form and the access of new energy discovery systems, the adaptability of conventional power system frequency safety and stability analysis models and analysis methods faces great challenges. Currently, although a boiler model has been established in the PSS / E software of the power system and can simulate the dynamic behavior of boiler fuel, the existing boiler model does not consider the influence of frequency change on the boiler thermal state and auxiliary machine output, and cannot accurately simulate the frequency characteristics of the system and analyze the frequency safety and stability characteristics when the frequency deviates greatly. Summary of the Invention

[0005] One of the purposes of the present invention is to provide a method for determining the influence of the frequency change of a transient process system on the thermal effect of a thermal power unit with high reliability and good accuracy.

[0006] Another purpose of the present invention is to provide a system for realizing the method for determining the influence of the frequency change of a transient process system on the thermal effect of a thermal power unit.

[0007] The method for determining the influence of the frequency change of a transient process system on the thermal effect of a thermal power unit provided by the present invention includes the following steps:

[0008] S1. Obtain the data information of the target thermal power unit;

[0009] S2. According to the data information obtained in step S1, construct a typical model of the steam turbine-governor of the target thermal power unit in the power system transient simulation software;

[0010] S3. Calculate the main steam flow rate data input to the steam turbine of the target thermal power unit based on the data information obtained in step S1;

[0011] S4. Based on the data information obtained in step S3, and in combination with the typical steam turbine-governor model constructed in step S2, calculate the parameter information considering the boiler thermal effect;

[0012] S5. Based on the data information obtained in step S4, calculate the thermal effect evaluation index and the system frequency safety margin index of the target thermal power unit;

[0013] S6. Based on the data information obtained in step S5, calculate the thermal effect frequency response index of the target thermal power unit, and complete the determination of the influence of the system frequency change during the transient process on the thermal effect of the target thermal power unit.

[0014] The steps of constructing the typical steam turbine-governor model of the target thermal power unit in the power system transient simulation software according to the data information obtained in step S1 described in step S2 are specifically as follows:

[0015] The processing process of the constructed typical steam turbine-governor model of the target thermal power unit includes:

[0016] The per-unit value of the system angular frequency deviation Δω is amplified and reversed by the frequency deviation amplification factor K without considering the boiler thermal effect, and then added to the opposite value of the actual steam turbine valve opening C V and the initial power P0 of the thermal power unit to obtain the first transfer signal u C which is u C = -KΔω + P0 - C V ;

[0017] The internal transfer signal u C is processed through the governor inertia link to obtain the second transfer signal u B which is where T3 is the time constant of the governor inertia link;

[0018] The second transfer signal u B is processed through the first limiter to obtain the limited second transfer signal u' B which is where U O is the upper limit value of the first limiter, and U C is the lower limit value of the first limiter;

[0019] The limited second transfer signal u' B at time t, after the simulation step Δt, obtains the change amount of the steam turbine valve opening ΔC V which is ΔC V = u' B ·Δt;

[0020] The change amount ΔC of the steam turbine control valve opening V After being processed by the integration link, the non-limited steam turbine control valve opening u is obtained A For u A = C V,int + ΔC V , C V,int is the value of the steam turbine control valve opening at time t;

[0021] The non-limited steam turbine control valve opening u A After being processed by the second limiting link, the actual steam turbine control valve opening is obtained where P MAX is the maximum value of the steam turbine control valve opening, and P MIN is the minimum value of the steam turbine control valve opening;

[0022] The actual steam turbine control valve opening C V and the boiler thermal state parameters are input into the steam turbine model together to obtain the final steam turbine output power P m ;

[0023] During the operation of the steam turbine, the main steam flow rate D input into the steam turbine te is the product of the boiler main steam pressure P t and the actual steam turbine control valve opening C V ; in the typical steam turbine-governor model of the target thermal power unit constructed, the boiler main steam pressure P t is set to 1, so D te = C V ·P t = C V ;

[0024] Since numerically C V = D te , so there is ΔC V = ΔD te ; ΔD te is the change value of the main steam flow rate input into the steam turbine;

[0025] When U C ≤ u B ≤ U O , there is ΔD te = u B ·Δt;

[0026] Thus, it is obtained

[0027] The main steam flow rate data input into the steam turbine of the target thermal power unit is calculated according to the data information obtained in step S1 described in step S3, and specifically includes the following steps:

[0028] Based on the data information obtained in step S1, using a Python program, based on the boiler thermal state, governor dynamics, boiler control system, and frequency deviation signal, calculate the main steam flow data D input to the steam turbine of the target thermal power unit. t ' e 。

[0029] According to the data information obtained in step S3, combined with the typical steam turbine-governor model constructed in step S2, calculate the parameter information considering the boiler thermal effect, specifically including the following steps:

[0030] Step S3 obtained the main steam flow data D input to the steam turbine of the target thermal power unit considering the boiler thermal effect. t ' e ;

[0031] In order to combine the typical steam turbine-governor model constructed in step S2, there is D te =D t ' e and ΔD te =ΔD t ' e ;where ΔD t ' e is the change value of the main steam flow data input to the steam turbine of the target thermal power unit considering the boiler thermal effect.

[0032] When U C ≤u B ≤U O , substitute D t ' e and ΔD t ' e into the calculation formula to obtain where K' is the frequency deviation amplification coefficient considering the boiler thermal effect after model combination.

[0033] According to Let the u B calculated through , be equal to the u B calculated through , so as to calculate the expression of K' as

[0034]

[0035] According to the data information obtained in step S4, calculate the thermal effect evaluation index and system frequency safety margin index of the target thermal power unit, specifically including the following steps:

[0036] Calculate the thermal effect evaluation index α of the target thermal power unit using the following formula:

[0037]

[0038] where K' min is the minimum value of the frequency deviation amplification factor considering the boiler thermal effect after the model combination calculated based on the data information obtained in step S4;

[0039] The system frequency safety margin index β of the target thermal power unit is calculated using the following formula:

[0040]

[0041] where f nadir is the minimum value of the system transient frequency; f cr,1 is the first-round low-frequency load shedding frequency threshold of the system; f N is the rated frequency value of the system.

[0042] According to the data information obtained in step S5 described in step S6, calculate the thermal effect frequency response index of the target thermal power unit, and complete the determination of the influence of the system frequency change during the transient process on the thermal effect of the target thermal power unit, which specifically includes the following steps:

[0043] The thermal effect frequency response index η of the target thermal power unit is calculated as

[0044] The determination of the influence of the system frequency change during the transient process on the thermal effect of the target thermal power unit is completed using the following rules:

[0045] The smaller the value of η, the smaller the influence of the system frequency change during the transient process on the thermal effect of the target thermal power unit, and the better the transient response ability of the target thermal power unit;

[0046] The larger the value of η, the greater the influence of the system frequency change during the transient process on the thermal effect of the target thermal power unit, and the worse the transient response ability of the target thermal power unit.

[0047] The present invention also provides a system for implementing a method for determining the influence of the frequency change of the transient process system on the thermal effect of a thermal power unit, including a data acquisition module, a model construction module, a flow calculation module, a parameter calculation module, an index calculation module, and an influence determination module; the data acquisition module, the model construction module, the flow calculation module, the parameter calculation module, the index calculation module, and the influence determination module are connected in series in sequence; the data acquisition module is used to acquire the data information of the target thermal power unit and upload the data information to the model construction module; the model construction module is used to construct a typical model of the steam turbine-governor of the target thermal power unit in the power system transient simulation software according to the received data information and upload the data information to the flow calculation module; the flow calculation module is used to calculate the main steam flow data input to the steam turbine of the target thermal power unit according to the received data information and upload the data information to the parameter calculation module; the parameter calculation module is used to calculate the parameter information considering the boiler thermal effect according to the received data information and the typical model of the steam turbine-governor constructed in step S2 and upload the data information to the index calculation module; the index calculation module is used to calculate the thermal effect evaluation index and the system frequency safety margin index of the target thermal power unit according to the received data information and upload the data information to the influence determination module; the influence determination module is used to calculate the thermal effect frequency response index of the target thermal power unit according to the received data information and complete the determination of the influence of the frequency change of the transient process system on the thermal effect of the target thermal power unit.

[0048] The method and system for determining the influence of the frequency change of the transient process system on the thermal effect of a thermal power unit provided by the present invention, through the construction of a typical model of the steam turbine-governor of the target thermal power unit, as well as joint simulation and corresponding calculations, not only realizes the determination of the influence of the frequency change of the transient process system on the thermal effect of the thermal power unit, but also has higher reliability and better accuracy. Description of the Drawings

[0049] Figure 1 It is a schematic flow chart of the method of the present invention.

[0050] Figure 2 It is a schematic diagram of the model structure of the steam turbine-governor typical model of the thermal power unit of the method of the present invention.

[0051] Figure 3 It is a schematic diagram of the model structure of the combined model of the method of the present invention.

[0052] Figure 4 It is a schematic diagram of the system structure of the IEEE10-machine 39-bus system in the embodiment of the method of the present invention.

[0053] Figure 5 Schematic diagram of simulation comparison between the implementation method of the method of the present invention and the extended model

[0054] Figure 6 Schematic diagram of the system frequency response curve under fault scenario 1 of the method embodiment of the present invention

[0055] Figure 7 Schematic diagram of the functional modules of the system of the present invention Detailed implementation manners

[0056] As Figure 1 shown in the following is the schematic diagram of the method flow of the method of the present invention: The determination method for the influence of the system frequency change during the transient process on the thermal effect of thermal power units disclosed in the present invention includes the following steps:

[0057] S1. Obtain the data information of the target thermal power unit;

[0058] S2. According to the data information obtained in step S1, in the power system transient simulation software, construct the typical model of the steam turbine-governor of the target thermal power unit; specifically including the following steps:

[0059] For the constructed typical model of the steam turbine-governor of the target thermal power unit (as Figure 2 shown), the processing process includes:

[0060] The per-unit value of the system angular frequency deviation Δω is amplified and reversed by the frequency deviation amplification factor K when not considering the boiler thermal effect, and then added to the opposite value of the actual throttle valve opening C V of the steam turbine and the initial power P0 of the thermal power unit to obtain the first transfer signal u C ( Figure 2 the signal at point C in C ) is u V =-KΔω + P0 - C

[0061] The internal transfer signal u C is processed through the governor inertia link to obtain the second transfer signal u B ( Figure 2 the signal at point B in where T3 is the time constant of the governor inertia link;

[0062] The second transfer signal u B is processed through the first limiter to obtain the limited second transfer signal u' B as where U O is the upper limit value of the first limiter, and U C is the lower limit value of the first limiter;

[0063] The limited second transfer signal u' BAt time t, after a simulation step size of Δt, the change in the steam turbine governing valve opening ΔC is obtained. V It is ΔC V = u' B ·Δt;

[0064] The change in the steam turbine governing valve opening ΔC V After being processed by the integration link, the unclamped steam turbine governing valve opening u is obtained. A It is u A = C V,int + ΔC V , where C V,int is the value of the steam turbine governing valve opening at time t;

[0065] The unclamped steam turbine governing valve opening u A After being processed by the second clamping link, the actual steam turbine governing valve opening C is obtained. V ( Figure 2 The signal at point A in where P MAX is the maximum value of the steam turbine governing valve opening, and P MIN is the minimum value of the steam turbine governing valve opening;

[0066] The actual steam turbine governing valve opening C V and the boiler thermal state parameters are input into the steam turbine model together to obtain the final steam turbine output power P. m ;

[0067] During the operation of the steam turbine, the main steam flow rate D input into the steam turbine te is the product of the boiler main steam pressure P t and the actual steam turbine governing valve opening C V ; in the typical steam turbine-governor model of the constructed target thermal power unit, the boiler main steam pressure P t is set to 1, so D te = C V ·P t = C V ;

[0068] Since numerically C V = D te , so there is ΔC V = ΔD te ; ΔD te is the change value of the main steam flow rate input into the steam turbine;

[0069] When U C ≤ u B ≤ U O , there is ΔD te = u B ·Δt;

[0070] Thus obtained

[0071] S3. According to the data information obtained in step S1, calculate the main steam flow data input to the steam turbine of the target thermal power unit; specifically, it includes the following steps:

[0072] In the typical model of the steam turbine-governor of the thermal power unit, taking the angular frequency deviation signal as the input, calculate the change rate of the steam turbine valve opening, and then obtain the valve opening, so as to obtain the main steam flow input to the steam turbine under the assumption condition of the main steam pressure; since the main steam pressure is usually assumed to be a constant value of 1, in the typical model of the steam turbine-governor of the thermal power unit, the values of the valve opening and its change rate are respectively equal to the values of the main steam flow of the steam turbine and its change rate;

[0073] According to the data information obtained in step S1, use a Python program to calculate the main steam flow data D input to the steam turbine of the target thermal power unit based on the boiler thermal state, governor dynamics, boiler control system, and frequency deviation signal t ' e ;

[0074] Specifically, in the existing control system of the thermal power unit, based on the boiler thermal state, governor dynamics, boiler control system, and frequency deviation signal, the coal feeding amount, water supply amount, and the main steam flow data D input to the steam turbine of the thermal power unit can be calculated t ' e , and then it can reflect the influence of system disturbances on the power generation process of the thermal power unit; therefore, the present invention implements this part of the content in a Python program and then feeds it back to the model parameters in PSS / E through the API interface, so that the model in PSS / E can consider the influence of the changes in the coal feeding amount and water supply amount of the thermal power unit on the boiler thermal state and the boiler control of the thermal power unit during the calculation process;

[0075] S4. According to the data information obtained in step S3, combined with the typical steam turbine-governor model constructed in step S2 (as shown in Figure 3 ), calculate the parameter information considering the boiler thermal effect; specifically, it includes the following steps:

[0076] Step S3 obtained the main steam flow data D input to the steam turbine of the target thermal power unit considering the boiler thermal effect t ' e ; In order to use the model structure within the red box in Figure 3 to achieve function expansion and co-simulation, that is, in order to combine the typical steam turbine-governor model constructed in step S2, then there is D te = D t ' e and ΔD te = ΔDt ' e ; Among them, ΔD t ' e is the change value of the main steam flow rate data input to the steam turbine after considering the boiler thermal effect of the target thermal power unit;

[0077] When U C ≤u B ≤U O , substitute D t ' e and ΔD t ' e into the calculation formula to obtain Among them, K' is the frequency deviation amplification coefficient considering the boiler thermal effect after the model combination;

[0078] According to Let the u calculated through B , be equal to the u calculated through B to calculate the expression of K' as

[0079]

[0080] S5. According to the data information obtained in step S4, calculate the thermal effect evaluation index and system frequency safety margin index of the target thermal power unit; specifically, the following steps are included:

[0081] Use the following formula to calculate the thermal effect evaluation index α of the target thermal power unit:

[0082]

[0083] In the formula, K' min is the minimum value of the frequency deviation amplification coefficient considering the boiler thermal effect after the model combination calculated according to the data information obtained in step S4; according to the thermal effect evaluation index α, it can be seen that the larger the thermal effect evaluation index value of the thermal power unit, the greater the change degree of the boiler heat storage capacity and the greater the change of the boiler main steam pressure during the transient process;

[0084] Use the following formula to calculate the system frequency safety margin index β of the target thermal power unit:

[0085]

[0086] In the formula, f nadir is the minimum value of the system transient frequency; f cr1 is the first-round low-frequency load shedding frequency threshold value of the system; f N is the rated frequency value of the system;

[0087] S6. Calculate the thermal effect frequency response index of the target thermal power unit based on the data information obtained in step S5, and complete the determination of the influence of the system frequency change during the transient process on the thermal effect of the target thermal power unit; specifically, it includes the following steps:

[0088] The calculated thermal effect frequency response index η of the target thermal power unit is

[0089] Adopt the following rules to complete the determination of the influence of the system frequency change during the transient process on the thermal effect of the target thermal power unit:

[0090] The smaller the value of η, the smaller the influence of the system frequency change during the transient process on the thermal effect of the target thermal power unit, and the better the transient response ability of the target thermal power unit;

[0091] The larger the value of η, the greater the influence of the system frequency change during the transient process on the thermal effect of the target thermal power unit, and the worse the transient response ability of the target thermal power unit.

[0092] The following further illustrates the method of the present invention in conjunction with an embodiment:

[0093] Take the IEEE39 bus system as an example, as Figure 4 shown; in the 39-bus system, the total installed capacity of the units is 6800MW, and the total load is 6140.8MW, where the 30th to 39th buses are generator buses and all the units are thermal power units.

[0094] Set the disturbance to 0.1 p.u., and the frequency response curve of the system is as Figure 5 shown. It can be seen from the simulation results that the method of the present invention has feasibility and good simulation accuracy.

[0095] Set the fault scenario: remove one generator at bus 38, the system loses active power of 830MW, and the disturbance magnitude is 12.21% of the system installed capacity. Consider the thermal effect changes of the boiler transient process in different models, and analyze the frequency response curves of different models under the same fault scenario. Among them, Model 1: PSS / E conventional system frequency response model; Model 2: Frequency response model with an extended boiler thermal effect model based on Model 1; Model 3: Extended frequency response model considering the boiler thermal effect change model.

[0096] When initially not considering the boiler thermal effect, the value of the frequency deviation amplification coefficient K is 20. Under fault scenario 1, use PSS / E software to analyze the system frequency response curves of different simulation models, as Figure 6 shown.

[0097] Model 1: PSS / E conventional system frequency response model:

[0098]

[0099] Model 2: On the basis of Model 1, expand the frequency response model of the boiler thermal effect model:

[0100]

[0101] Model 2: When in the initial state, change the boiler thermal state to a non - rated state:

[0102]

[0103] Model 3: Consider the expanded frequency response model of the boiler thermal effect change model:

[0104]

[0105]

[0106] Through the above analysis, it can be seen that when the boiler thermal effect is not considered, the frequency deviation amplification factor is a constant value. At this time, the thermal storage capacity of the thermal power unit boiler is good, and it can respond well to the system transient response process; when the boiler thermal effect is considered, the frequency deviation amplification factor changes with the transient process, and the initial thermal effect state of the boiler has a great influence on the transient response process of the thermal power unit.

[0107] The solution of the present invention can further quantitatively analyze the influence of the change of the boiler thermal effect on the system transient response through the change of the frequency deviation amplification factor, and at the same time can quantitatively analyze the frequency response index of the thermal effect of the thermal power unit, and then analyze the influence of the system frequency change on the thermal storage of the thermal power unit boiler.

[0108] Such as Figure 7The following is a schematic diagram of the functional modules of the system of the present invention: The system for implementing the method for determining the influence of the frequency change of the transient process system on the thermal effect of a thermal power unit disclosed in the present invention includes a data acquisition module, a model construction module, a flow calculation module, a parameter calculation module, an index calculation module, and an influence determination module; the data acquisition module, the model construction module, the flow calculation module, the parameter calculation module, the index calculation module, and the influence determination module are connected in series in sequence; the data acquisition module is used to acquire the data information of the target thermal power unit and upload the data information to the model construction module; the model construction module is used to construct a typical steam turbine-governor model of the target thermal power unit in the power system transient simulation software according to the received data information, and upload the data information to the flow calculation module; the flow calculation module is used to calculate the main steam flow data input to the steam turbine of the target thermal power unit according to the received data information, and upload the data information to the parameter calculation module; the parameter calculation module is used to calculate the parameter information considering the boiler thermal effect according to the received data information and the typical steam turbine-governor model constructed in step S2, and upload the data information to the index calculation module; the index calculation module is used to calculate the thermal effect evaluation index and the system frequency safety margin index of the target thermal power unit according to the received data information, and upload the data information to the influence determination module; the influence determination module is used to calculate the thermal effect frequency response index of the target thermal power unit according to the received data information, and complete the determination of the influence of the frequency change of the transient process system on the thermal effect of the target thermal power unit.

Claims

1. A method for determining the influence of frequency change in a transient process system on the thermal effect of a thermal power unit, comprising the following steps: S1. Obtain the data information of the target thermal power unit; S2. According to the data information obtained in step S1, construct a typical model of the steam turbine-governor of the target thermal power unit in a power system transient simulation software; S3. According to the data information obtained in step S1, calculate the main steam flow rate data input to the steam turbine of the target thermal power unit; S4. According to the data information obtained in step S3, combined with the typical model of the steam turbine-governor constructed in step S2, calculate the parameter information considering the boiler thermal effect; S5. According to the data information obtained in step S4, calculate the thermal effect evaluation index and the system frequency safety margin index of the target thermal power unit; S6. According to the data information obtained in step S5, calculate the thermal effect frequency response index of the target thermal power unit, and complete the determination of the influence of frequency change in the transient process system on the thermal effect of the target thermal power unit.

2. The determination method for the influence of the frequency change in the transient process system on the thermal effect of a thermal power unit according to claim 1, characterized in that The step of constructing a typical model of the steam turbine-governor of the target thermal power unit in a power system transient simulation software according to the data information obtained in step S1 specifically includes the following steps: The processing process of the constructed typical model of the steam turbine-governor of the target thermal power unit includes: The per-unit value of the system angular frequency deviation Δω is amplified and reversed by the frequency deviation amplification factor K when the boiler thermal effect is not considered, and then added to the opposite value of the actual turbine valve opening C V and the initial power P0 of the thermal power unit to obtain the first transfer signal u C For u C = -KΔω + P0 - C V ; Internal transfer signal u C Processed by the governor inertia link to obtain the second transfer signal u B For T3 is the time constant of the governor inertia link; The second transfer signal u B After being processed by the first clipping circuit, the clipped second transfer signal u' is obtained B which is where U O is the upper limit value of the first clipping circuit, and U C is the lower limit value of the first clipping circuit; Limited second transfer signal u' B At time t, after a simulation step size Δt, the change ΔC in the steam turbine valve opening is obtained V For ΔC V = u' B ·Δt; The change in the opening of the steam turbine control valve ΔC V After being processed by the integration link, the unclamped opening of the steam turbine control valve u is obtained A For u A = C V,int + ΔC V , C V,int is the value of the opening of the steam turbine control valve at time t; Unlimited steam turbine valve opening u A After being processed by the second limiting link, the actual steam turbine valve opening C is obtained V is where P MAX is the maximum value of the steam turbine valve opening, and P MIN is the minimum value of the steam turbine valve opening; Actual throttle opening C of steam turbine V and boiler thermal state parameters are input into the steam turbine model together to obtain the final output power P of the steam turbine m ; During the operation of the steam turbine, the main steam flow rate D input to the steam turbine te is the product of the main steam pressure P of the boiler t and the actual throttle valve opening C of the steam turbine V ; in the typical steam turbine-governor model of the target thermal power unit constructed, the main steam pressure P of the boiler is set t to 1, so D is obtained te = C V ·P t = C V ; Since numerically C V = D te , there is thus a ΔC V = ΔD te ; ΔD te is the change value of the main steam flow rate entering the steam turbine; When U C ≤u B ≤U O there exists ΔD te = u B ·Δt; Thus obtained 3. The method for determining the influence of the frequency change in the transient process system on the thermal effect of a thermal power unit according to claim 2, wherein The step of calculating the main steam flow rate data input to the steam turbine of the target thermal power unit according to the data information obtained in step S1 specifically includes the following steps: Based on the data information obtained in step S1, using a Python program, based on the boiler thermal state, governor dynamics, boiler control system, and frequency deviation signal, calculate the main steam flow rate data D input to the steam turbine of the target thermal power unit t ' e .

4. The method for determining the influence of the frequency change of the transient process system on the thermal effect of a thermal power unit according to claim 3, characterized in that The step of calculating the parameter information considering the boiler thermal effect according to the data information obtained in step S3, combined with the typical model of the steam turbine-governor constructed in step S2, specifically includes the following steps: In step S3, the main steam flow rate data D of the steam turbine input after considering the boiler thermal effect of the target thermal power unit is obtained. t ' e ; To combine with the typical turbine-governor model constructed in step S2, there exists D te = D t ' e and ΔD te = ΔD t ' e ; where ΔD t ' e is the change value of the main steam flow rate data input to the turbine after considering the boiler thermal effect of the target thermal power unit; When U C ≤u B ≤U O , substitute D t ' e and ΔD t ' e into the calculation formula to obtain where K' is the frequency deviation amplification factor considering the boiler thermal effect after the model combination; According to Let the u calculated through B , be equal to the u calculated through B , thus the expression for K' is calculated as 5. The determination method for the influence of the frequency change of the transient process system on the thermal effect of a thermal power unit according to claim 4, characterized in that The step of calculating the thermal effect evaluation index and the system frequency safety margin index of the target thermal power unit according to the data information obtained in step S4 specifically includes the following steps: Calculate the thermal effect evaluation index α of the target thermal power unit by using the following formula: where K' min is the minimum value of the frequency deviation amplification factor considering the boiler thermal effect after the model combination calculated from the data information obtained in step S4; Calculate the system frequency safety margin index β of the target thermal power unit by using the following formula: where f nadir is the minimum value of the system transient frequency; f cr,1 is the first-round low-frequency load shedding frequency threshold of the system; f N is the rated frequency value of the system.

6. The determination method for the influence of the frequency change of the transient process system on the thermal effect of a thermal power unit according to claim 5, characterized in that The step of calculating the thermal effect frequency response index of the target thermal power unit according to the data information obtained in step S5, and completing the determination of the influence of frequency change in the transient process system on the thermal effect of the target thermal power unit specifically includes the following steps: The calculated thermal effect frequency response index η of the target thermal power unit is Complete the determination of the influence of frequency change in the transient process system on the thermal effect of the target thermal power unit by using the following rules: The smaller the value of η, the smaller the influence of frequency change in the transient process system on the thermal effect of the target thermal power unit, and the better the transient response ability of the target thermal power unit; The larger the value of η, the greater the influence of frequency change in the transient process system on the thermal effect of the target thermal power unit, and the worse the transient response ability of the target thermal power unit.

7. A system for implementing the determination method of the influence of the frequency change of the transient process system on the thermal effect of a thermal power unit as described in any one of claims 1 to 6, characterized in that It includes a data acquisition module, a model construction module, a flow calculation module, a parameter calculation module, an index calculation module, and an impact determination module; the data acquisition module, the model construction module, the flow calculation module, the parameter calculation module, the index calculation module, and the impact determination module are connected in series in sequence; the data acquisition module is used to acquire the data information of the target thermal power unit and upload the data information to the model construction module; the model construction module is used to construct a typical model of the steam turbine-governor of the target thermal power unit in the power system transient simulation software according to the received data information, and upload the data information to the flow calculation module; The flow calculation module is used to calculate the main steam flow data input to the steam turbine of the target thermal power unit according to the received data information, and upload the data information to the parameter calculation module; The parameter calculation module is used to calculate the parameter information considering the boiler thermal effect according to the received data information, combined with the typical model of the steam turbine-governor constructed in step S2, and upload the data information to the index calculation module; The index calculation module is used to calculate the thermal effect evaluation index and the system frequency safety margin index of the target thermal power unit according to the received data information, and upload the data information to the impact determination module; The impact determination module is used to calculate the thermal effect frequency response index of the target thermal power unit according to the received data information, and complete the determination of the impact of the system frequency change during the transient process on the thermal effect of the target thermal power unit.

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