Control method for starting parallel points of combined cycle unit

Abstract

The invention provides a combined cycle unit starting paralleling point control method, which comprises the following steps: acquiring key operation parameters, and establishing a physical model and an iterative model; an optimization starting scheme is generated through model association and iterative calculation; calculating the total energy consumption reduction based on the scheme and the consumption reduction model; the optimization scheme is sent to front-end equipment to automatically control the unit to act; the method can reduce fuel and steam consumption, reduce energy consumption, accelerate to reach a stable state, improve response speed, accurately control flow, realize smooth transition, prolong equipment life, enhance controllability and predictability of a starting process, reduce cost, improve economic benefits, reduce emission, facilitate environmental protection, quickly respond to power grid requirements and enhance system reliability.

Description

Technical Field

[0001] The present invention relates to the technical field of power system control, and in particular to a control method for a start-up parallel point of a combined cycle unit. Background Art

[0002] Combined cycle power generation units are widely used around the world as a highly efficient power generation method. This power generation system combines the advantages of gas turbines and steam turbines. The high-temperature exhaust gas generated by the gas turbine heats the boiler to generate steam, which in turn drives the steam turbine to generate electricity, thus realizing the cascade utilization of energy and significantly improving power generation efficiency. With the growth of electricity demand and technological advancement, the design and operation of combined cycle power generation units face new challenges. On the one hand, in order to cope with climate change and environmental protection needs, reducing fossil fuel consumption and emissions has become one of the important development goals. On the other hand, the intensified competition in the electricity market has prompted power generation companies to seek more efficient operating methods to reduce costs and improve competitiveness.

[0003] Although combined cycle power generation units have high efficiency, there are still some technical problems in the startup phase that affect their overall performance and economic benefits; these problems mainly include but are not limited to:

[0004] During the startup process, the inaccurate adjustment of gas turbine and steam turbine parameters leads to high energy consumption, especially low efficiency in the use of fuel and steam;

[0005] Existing startup methods often take a long time to reach a stable operating state, which not only increases startup costs but also affects the flexibility of grid dispatch;

[0006] In the initial stage of startup, due to imperfect control strategies, the operating parameters of gas turbines and steam turbines may fluctuate greatly, causing potential damage to the equipment;

[0007] It is difficult to achieve precise control of fuel flow and steam flow during the startup phase with existing technologies, which limits further improvement of startup efficiency. Summary of the invention

[0008] The present invention provides a control method for starting parallel points of a combined cycle unit to solve the problems of large energy loss, long starting time and parameter fluctuation existing in the prior art.

[0009] The present invention provides a method for controlling a start-up parallel point of a combined cycle unit, comprising:

[0010] Step 1: Collect the key operating parameters of the current unit and establish a physical model related to the flow parameters and speed parameters of the unit;

[0011] Step 2: Establishing the relevant iterative model of the flow parameters and speed parameters of the unit;

[0012] Step 3, associating the relevant physical model with the relevant iterative model, substituting the current operating parameters into the associated model for iteration, and generating an optimized parallel point startup plan;

[0013] Step 4: Based on the parallel point start-up plan and the preset consumption reduction model, calculate and record the total energy consumption reduced by the plan;

[0014] Step 5: Send the parallel point starting plan to the front-end device, and automatically control the action of the unit according to the parallel point starting plan.

[0015] According to a control method for starting parallel points of a combined cycle unit provided by the present invention, in step one, the key operating parameters include: the rotational speed of the gas turbine and the steam turbine, the fuel flow rate, the steam flow rate, the gain coefficient, the damping coefficient, the time constant, and the energy consumption per unit time of the gas turbine, the energy consumption per unit time of the steam turbine, and the loss per unit time of the unit.

[0016] According to a control method for starting parallel point of a combined cycle unit provided by the present invention, in step 1, the related physical model includes a gas turbine physical model and a steam turbine physical model;

[0017] The gas turbine physical model is:

[0018]

[0019] Among them, ω GT0 is the initial speed of the gas turbine, dτ is the time step, ω GT (τ) is the speed of the gas turbine after the time step dτ, τ GT is the time constant of the gas turbine, K GT is the gain factor of the gas turbine, D GT is the damping coefficient of the gas turbine, is the fuel flow rate;

[0020] The physical model of the steam turbine is:

[0021]

[0022] Among them, ω ST0 is the initial speed of the steam turbine, dτ is the time step, ω ST (τ) is the speed of the steam turbine after a time step of dτ, τ ST is the time constant of the steam turbine, K ST is the gain factor of the steam turbine, D ST is the damping coefficient of the steam turbine, is the steam flow rate.

[0023] According to a control method for starting parallel point of a combined cycle unit provided by the present invention, in step 2, the related iterative model includes a gas turbine iterative model and a steam turbine iterative model;

[0024] The gas turbine iteration model is:

[0025]

[0026] in, is the fuel flow rate before iteration, is the fuel flow after iteration; is the target speed of the gas turbine, is the gas turbine speed before iteration, K p1 is the proportional gain, K i1 is the integral gain, dτ is the time step;

[0027] The steam turbine iteration model is:

[0028]

[0029] in, is the steam flow rate before iteration, is the steam flow rate after iteration; is the target speed of the steam turbine, is the steam turbine speed before iteration, K P2 is the proportional gain, K i2 is the integral gain, and dτ is the time step.

[0030] According to a control method for starting a parallel point of a combined cycle unit provided by the present invention, in step three, associating the relevant physical model with the relevant iterative model, substituting the current operating parameters into the associated model for iteration, and generating a parallel point starting plan includes:

[0031] S31, associating the gas turbine physical model with the gas turbine iterative model to form a gas turbine associated model; associating the steam turbine physical model with the steam turbine iterative model to form a steam turbine associated model;

[0032] S32, when put into operation, the speed and flow rate in the initial state are substituted into the physical model of the gas turbine and the physical model of the steam turbine to obtain the speed ω of the gas turbine after a time step dτ GT (τ) and steam turbine speed ω ST (τ);

[0033] S33, the gas turbine speed ω after a time step dτGT (τ) and steam turbine speed ω ST (τ) is correspondingly substituted into the gas turbine iteration model and the steam turbine iteration model, replacing the gas turbine speed before iteration in the iteration model and the steam turbine speed before iteration

[0034] S34, after the iterative model calculation, the fuel flow rate after a time step dτ is obtained and recorded and steam flow

[0035] S35, the fuel flow after a time step dτ and steam flow Substitute it into the gas turbine physical model and the steam turbine physical model again, replace the fuel flow and steam flow in the physical model, calculate and record the gas turbine speed ω after the second time step 2dτ GT (2τ) and steam turbine speed ω ST (2τ);

[0036] S36, the gas turbine speed ω after the second time step 2dτ GT (2τ) and steam turbine speed ω ST (2τ) is substituted into the iterative model again, replacing the gas turbine speed before iteration and the steam turbine speed before iteration Get and record the fuel flow rate after the second time step 2dτ and steam flow

[0037] S37, repeat the above steps until and are all 0, and it is defined as steady state; record the number of time steps required for the gas turbine and steam turbine to reach steady state, as well as the fuel flow of the gas turbine at each time step and steam flow rate of steam turbine

[0038] S38, generating an optimized parallel point startup plan based on the recorded content.

[0039] According to a control method for starting a parallel point of a combined cycle unit provided by the present invention, in step 4, the calculation and recording of the total energy consumption reduced by the parallel point starting scheme based on the parallel point starting scheme and a preset consumption reduction model includes:

[0040] S41, pre-establishing an energy consumption calculation model for a common solution:

[0041]

[0042] Among them, E to (t) is the total energy consumption of the total time step under the general scheme, E GT (t) is the energy consumption of gas turbine under the common scheme, E ST (t) is the energy consumption of steam turbine under the common scheme, E loss (t) is the unit loss under the common scheme, and t is the total time period corresponding to the total time step;

[0043] S42, establishing an energy consumption calculation model for the optimization scheme:

[0044]

[0045] in, is the energy consumption reduced by the optimized parallel point starting scheme compared with the ordinary scheme, E to (t) is the total energy consumption of the total time step under the common scheme, c1 is the first weight coefficient, c2 is the second weight coefficient, and t is the total time period corresponding to the total time step;

[0046] S43, the energy consumption reduced by the optimized parallel point starting scheme compared with the ordinary scheme Recorded in the database.

[0047] A method for controlling a start-up parallel point of a combined cycle unit provided by the present invention further includes:

[0048] Energy consumption reduction based on the optimized parallel point startup scheme compared with the ordinary scheme Determine whether to adopt the optimized parallel point startup plan.

[0049] According to a control method for starting a parallel point of a combined cycle unit provided by the present invention, in step five, the parallel point starting plan is sent to a front-end device, and the action of automatically controlling the unit according to the parallel point starting plan includes:

[0050] Convert each time step in the parallel point start-up scheme into a time period, and associate the time period with the fuel flow rate of the gas turbine to which the time step corresponds and steam flow rate of steam turbine match;

[0051] The fuel flow and steam flow of the gas turbine and steam turbine are controlled in each time period through the front-end equipment, and parallel point start-up is performed in the last time period.

[0052] Compared with the prior art, the present invention has the following beneficial effects:

[0053] 1. By optimizing the startup plan, the fuel and steam consumption of gas turbines and steam turbines during the startup process can be effectively reduced, reducing overall energy consumption.

[0054] 2. The optimized startup scheme can reach a stable operating state faster, shorten the time from startup to grid connection, and improve the response speed and availability of the unit.

[0055] 3. The present invention precisely controls the fuel flow and steam flow of the gas turbine and steam turbine, so that the unit can transition to a stable operating state more smoothly, reduce parameter fluctuations, and extend the life of the equipment.

[0056] 4. By establishing physical models and iterative models and performing iterative calculations, the time required to reach a stable state can be predicted more accurately, enhancing the controllability and predictability of the startup process.

[0057] 5. Reducing energy loss and shortening startup time means reducing startup costs, which is crucial to improving the economic benefits of power generation companies.

[0058] 6. By reducing fuel consumption during the startup phase, the present invention helps reduce greenhouse gas emissions and other pollutants, which is beneficial to environmental protection.

[0059] 7. The optimized startup scheme enables the combined cycle generator set to respond to grid demand more quickly, enhancing the reliability and stability of the power system.

[0060] In summary, the present invention not only improves the startup efficiency but also reduces the cost and environmental impact of the startup phase through a series of precise control strategies, which is of great significance for improving the overall performance of the combined cycle power generation unit.

[0061] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description and the accompanying drawings.

[0062] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0064] Figure 1 It is a flow chart of a control method for starting a parallel point of a combined cycle unit provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0065] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0066] Embodiment 1:

[0067] The embodiment of the present invention provides a method for controlling the start-up parallel point of a combined cycle unit. Figure 1 ,include:

[0068] Step 1: Collect the key operating parameters of the current unit and establish a physical model related to the flow parameters and speed parameters of the unit;

[0069] Step 2: Establishing the relevant iterative model of the flow parameters and speed parameters of the unit;

[0070] Step 3: associate the relevant physical model with the relevant iteration model, substitute the current operation parameters into the associated model for iteration, and generate an optimized parallel point startup plan;

[0071] Step 4: Based on the parallel point start-up plan and the preset consumption reduction model, calculate and record the total energy consumption reduced by the plan;

[0072] Step 5: Send the parallel point start-up plan to the front-end equipment, and automatically control the operation of the unit according to the parallel point start-up plan.

[0073] The principle of the above embodiment is: to obtain real-time data of the unit under different operating conditions, such as parameters such as steam flow, gas flow, rotation speed, etc., use these data to establish a physical model to describe the relationship between these parameters, and further develop a model that can be solved iteratively, combine the physical model and the iterative model, and substitute the actual operating data for calculation to obtain the optimal solution; that is, to obtain a startup plan that can minimize startup time and energy consumption; use a specific model (consumption reduction model) to calculate how much energy the optimized plan saves compared to the original plan; send the optimized startup plan to the control system to realize the automated startup process.

[0074] The beneficial effects of the above embodiments are: reaching a stable operating state more quickly and shortening the time of non-full-load operation; reducing unnecessary fuel consumption and power loss; reducing mechanical wear caused by frequent startup; reducing operating costs and improving overall efficiency; and reducing greenhouse gas emissions and other pollutant emissions.

[0075] In order to further optimize the above embodiment, in step one, the key operating parameters include: the rotation speed of the gas turbine and the steam turbine, the fuel flow rate, the steam flow rate, the gain coefficient, the damping coefficient, the time constant, and the energy consumption per unit time of the gas turbine, the energy consumption per unit time of the steam turbine, and the loss per unit time of the unit.

[0076] It should be noted that the gas turbine speed reflects the working state of the gas turbine, the steam turbine speed reflects the working state of the steam turbine, the fuel flow rate affects the power generated by the gas turbine, the steam flow rate affects the power generated by the steam turbine, the gain coefficient describes the proportional relationship between the system output change-speed and the input change-flow rate, the damping coefficient affects the dynamic response speed of the system, the time constant determines the speed of system response, the unit time energy consumption of the gas turbine is the energy consumed by the gas turbine per unit time, the unit time energy consumption of the steam turbine is the energy consumed by the steam turbine per unit time, and the unit time loss of the unit is the additional energy loss of the entire unit per unit time.

[0077] To further optimize the above embodiment, in step 1, the relevant physical models include a gas turbine physical model and a steam turbine physical model;

[0078] The physical model of the gas turbine is:

[0079]

[0080] Among them, ω gT0 is the initial speed of the gas turbine, dτ is the time step, ω GT (τ) is the speed of the gas turbine after the time step dτ, τ GT is the time constant of the gas turbine, K GT is the gain factor of the gas turbine, D GT is the damping coefficient of the gas turbine, is the fuel flow rate;

[0081] The physical model of the steam turbine is:

[0082]

[0083] Among them, ω ST0 is the initial speed of the steam turbine, dτ is the time step, ω ST (τ) is the speed of the steam turbine after a time step of dτ, τ ST is the time constant of the steam turbine, K ST is the gain factor of the steam turbine, D ST is the damping coefficient of the steam turbine, is the steam flow rate.

[0084] It should be noted that these two physical models are used to describe the speed variation law of gas turbines and steam turbines under the action of given control signals (fuel flow and steam flow); the models are based on the first-order linear system theory, taking into account the inertia and damping characteristics of the system;

[0085] The gain coefficient indicates the intensity of the system's response to the input signal; the damping coefficient reflects the system's ability to suppress external disturbances; the time constant determines the speed of the system's response; all are known from actual operating conditions or the unit supplier.

[0086] To further optimize the above embodiment, in step 2, the relevant iterative models include a gas turbine iterative model and a steam turbine iterative model;

[0087] The gas turbine iteration model is:

[0088]

[0089] in, is the fuel flow rate before iteration, is the fuel flow rate after iteration; is the target speed of the gas turbine, is the gas turbine speed before iteration, K p1 is the proportional gain, K i1 is the integral gain, dτ is the time step;

[0090] The steam turbine iteration model is:

[0091]

[0092] in, is the steam flow rate before iteration, is the steam flow rate after iteration; is the target speed of the steam turbine, is the steam turbine speed before iteration, K P2 is the proportional gain, K i2 is the integral gain, and dτ is the time step.

[0093] It should be noted that the iterative model is used to adjust the fuel flow and steam flow to achieve the target speed; the PID (proportional-integral-derivative) controller concept is adopted, involving proportional and integral parts;

[0094] The proportional term adjusts the fuel flow and steam flow according to the deviation between the current speed and the target speed; when the deviation increases, the controller will increase the fuel or steam flow accordingly to accelerate the target speed; the proportional gain should be set large enough to quickly respond to the speed deviation, but not too large to cause overshoot or oscillation, which is obtained from the actual operation process;

[0095] The integral term is used to eliminate any remaining deviation, even if it is small; the integral term accumulates the deviation history from startup to the present moment, ensuring that adjustments to the fuel flow or steam flow can eliminate any steady-state errors over time; the integral gain should be small enough to avoid integral windup, but large enough to ensure that long-term errors are eliminated, as obtained during actual operation.

[0096] In order to further optimize the above embodiment, in step 3, the relevant physical model is associated with the relevant iteration model, the current operation parameters are substituted into the associated model for iteration, and the parallel point startup scheme is generated, including:

[0097] S31, associating the gas turbine physical model with the gas turbine iterative model to form a gas turbine associated model; associating the steam turbine physical model with the steam turbine iterative model to form a steam turbine associated model;

[0098] S32, when put into operation, the speed and flow rate in the initial state are substituted into the physical model of the gas turbine and the physical model of the steam turbine to obtain the speed ω of the gas turbine after a time step dτ GT (τ) and steam turbine speed ω ST (τ);

[0099] S33, the gas turbine speed ω after a time step dτ GT (τ) and steam turbine speed ω ST (τ) is substituted into the gas turbine iteration model and the steam turbine iteration model to replace the gas turbine speed before iteration in the iteration model. and the steam turbine speed before iteration

[0100] S34, after the iterative model calculation, the fuel flow after a time step dτ is obtained and recorded and steam flow

[0101] S35, the fuel flow after a time step dτ and steam flow Substitute it into the gas turbine physical model and steam turbine physical model again, replace the fuel flow and steam flow in the physical model, calculate and record the gas turbine speed ω after the second time step 2dτ GT (2τ) and steam turbine speed ω ST (2τ);

[0102] S36, the gas turbine speed ω after the second time step 2dτ GT (2τ) and steam turbine speed ω ST(2τ) is substituted into the iterative model again, replacing the gas turbine speed before iteration and the steam turbine speed before iteration Get and record the fuel flow rate after the second time step 2dτ and steam flow

[0103] S37, repeat the above steps until and are all 0, and it is defined as steady state; record the number of time steps required for the gas turbine and steam turbine to reach steady state, as well as the fuel flow of the gas turbine at each time step and steam flow rate of steam turbine

[0104] S38, generating an optimized parallel point startup plan based on the recorded content.

[0105] It should be noted that in actual application, the proportional gain and integral gain of the controller need to be adjusted according to the response of the system to obtain the best control performance; the steady-state condition usually means that the target speed and the actual speed are the same or the difference is less than a preset threshold; this threshold needs to be set according to the actual application requirements; the time step should not be too short, resulting in excessive calculation, nor too long, resulting in poor control effect; in general, the choice of time step should take into account the dynamic characteristics of the system and the limitations of computing resources.

[0106] In order to further optimize the above embodiment, in step 4, based on the parallel point start-up scheme and the preset consumption reduction model, the total energy consumption reduced by the scheme is calculated and recorded, including:

[0107] S41, pre-establishing an energy consumption calculation model for a common solution:

[0108]

[0109] Among them, E to (t) is the total energy consumption of the total time step under the general scheme, E GT (t) is the energy consumption of gas turbine under the common scheme, E ST (t) is the energy consumption of steam turbine under the common scheme, E loss (t) is the unit loss under the common scheme, and t is the total time period corresponding to the total time step;

[0110] S42, establishing an energy consumption calculation model for the optimization scheme:

[0111]

[0112] in, is the energy consumption reduced by the optimized parallel point starting scheme compared with the ordinary scheme, E to (t) is the total energy consumption of the total time step under the common scheme, c1 is the first weight coefficient, c2 is the second weight coefficient, and t is the total time period corresponding to the total time step;

[0113] S43, the energy consumption reduced by the optimized parallel point starting scheme compared with the ordinary scheme Recorded in the database.

[0114] It should be noted that the process described in step 4 is to evaluate the energy saving of the optimized parallel point starting scheme compared with the ordinary starting scheme; the energy consumption reduction of the optimized parallel point starting scheme compared with the ordinary scheme is recorded in the database; this is helpful for subsequent analysis and comparison of the advantages and disadvantages of different starting schemes;

[0115] Among them, gas turbine energy consumption is usually related to fuel consumption rate, which can be calculated by fuel flow rate and calorific value;

[0116] Steam turbine energy consumption is related to steam consumption rate, which can also be calculated from steam flow rate and calorific value;

[0117] Unit losses include mechanical losses, heat losses, etc. These losses are usually related to operating conditions (such as temperature, pressure, etc.);

[0118] The first weight coefficient is used to balance the relationship between energy consumption and cost, and a higher coefficient means more emphasis is placed on reducing energy consumption;

[0119] The second weight coefficient is used to balance the relationship between energy consumption and startup time. A higher coefficient means more emphasis is placed on shortening the startup time.

[0120] All are set based on actual operating conditions;

[0121] Objective Function Minimization means reducing the startup time as much as possible while meeting a certain energy consumption level, or reducing energy consumption as much as possible within a given time;

[0122] Recording the total energy consumption reduction of the optimized tie-point starting scheme is very important for future adjustment of starting strategies, improvement of energy efficiency, and decision making.

[0123] In order to further optimize the above embodiment, it also includes:

[0124] Energy consumption reduction based on the optimized parallel point startup scheme compared with the ordinary scheme Determine whether to adopt the optimized parallel point startup plan.

[0125] It should be noted that if the optimized parallel point starting scheme can significantly reduce energy consumption, then the optimized starting scheme is adopted; otherwise, the ordinary starting scheme is continued to be used; or a threshold is set as needed, and if the energy consumption reduced by the optimized parallel point starting scheme exceeds this threshold, then the scheme is considered worthy of adoption;

[0126] In addition to the amount of energy consumption reduction, other factors need to be considered, such as startup time, equipment life, maintenance costs, etc. These factors may have an impact on the final decision and can be added to the model in the form of coefficients for regulation;

[0127] In actual applications, the optimization strategy can be flexibly adjusted according to changes in operating conditions to adapt to different operating conditions; by continuously collecting and analyzing operating data, the startup plan can be continuously optimized to further improve energy efficiency.

[0128] In order to further optimize the above embodiment, in step 5, the parallel point start-up plan is sent to the front-end device, and the actions of automatically controlling the unit according to the parallel point start-up plan include:

[0129] Convert each time step in the parallel point start-up scheme into a time period, and associate the time period with the fuel flow of the gas turbine to which the time step belongs. and steam flow rate of steam turbine match;

[0130] The fuel flow and steam flow of the gas turbine and steam turbine are controlled in each time period through the front-end equipment, and parallel point start-up is performed in the last time period.

[0131] It should be noted that the process described in step five is to convert the optimized parallel point startup plan into actual operation instructions, which are executed by the front-end equipment to automatically control the actions of the gas turbine and steam turbine;

[0132] Convert the previously calculated time step into the time period in actual operation, such as converting the time step into seconds or minutes;

[0133] Match each time period with the fuel flow and steam flow of the corresponding time step in the optimized parallel point startup plan;

[0134] Use front-end equipment (such as PLC, DCS or other control systems) to control the fuel flow and steam flow of gas turbines and steam turbines in each time period;

[0135] A tie point start is performed at the end of the last time period;

[0136] The time step may be fixed or variable during calculation, but in actual operation it needs to be converted into a time period that is easy to understand and execute, such as 30 seconds, 1 minute, etc.;

[0137] The front-end equipment needs to be able to accurately control the fuel flow and steam flow to ensure that the gas turbine and steam turbine can smoothly reach the target speed according to the optimized parallel point start-up plan;

[0138] The timing of parallel point start-up is after the gas turbine and steam turbine have reached the target speed and the system has reached steady state;

[0139] In this way, the optimized parallel point startup plan can be converted into actual operating instructions, which are executed by the front-end equipment to automatically control the actions of the gas turbine and steam turbine, thereby achieving an efficient and energy-saving startup process.

[0140] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for controlling the start-up parallel point of a combined cycle unit, characterized in that: include: Step 1: Collect the key operating parameters of the current unit and establish a physical model related to the flow parameters and speed parameters of the unit; Step 2: Establishing the relevant iterative model of the flow parameters and speed parameters of the unit; Step 3, associating the relevant physical model with the relevant iterative model, substituting the current operating parameters into the associated model for iteration, and generating an optimized parallel point startup plan; Step 4: Based on the parallel point start-up plan and the preset consumption reduction model, calculate and record the total energy consumption reduced by the plan; Step 5: Send the parallel point starting plan to the front-end device, and automatically control the action of the unit according to the parallel point starting plan.

2. A method for controlling the start-up parallel point of a combined cycle unit according to claim 1, characterized in that: In step one, the key operating parameters include: the rotation speed of the gas turbine and the steam turbine, the fuel flow rate, the steam flow rate, the gain coefficient, the damping coefficient, the time constant, and the energy consumption per unit time of the gas turbine, the energy consumption per unit time of the steam turbine, and the loss per unit time of the unit.

3. A method for controlling the startup parallel point of a combined cycle unit according to claim 2, characterized in that: In step 1, the related physical models include a gas turbine physical model and a steam turbine physical model; The gas turbine physical model is: Among them, ω GT0 is the initial speed of the gas turbine, dτ is the time step, ω GT (τ) is the speed of the gas turbine after the time step dτ, τ GT is the time constant of the gas turbine, K GT is the gain factor of the gas turbine, D GT is the damping coefficient of the gas turbine, is the fuel flow rate; The physical model of the steam turbine is: Among them, ω ST0 is the initial speed of the steam turbine, dτ is the time step, ω ST (τ) is the speed of the steam turbine after a time step of dτ, τ ST is the time constant of the steam turbine, K ST is the gain factor of the steam turbine, D ST is the damping coefficient of the steam turbine, is the steam flow rate.

4. A method for controlling the start-up parallel point of a combined cycle unit according to claim 3, characterized in that: In step 2, the related iterative models include a gas turbine iterative model and a steam turbine iterative model; The gas turbine iteration model is: in, is the fuel flow rate before iteration, is the fuel flow after iteration; is the target speed of the gas turbine, is the gas turbine speed before iteration, K p1 is the proportional gain, K i1 is the integral gain, dτ is the time step; The steam turbine iteration model is: in, is the steam flow rate before iteration, is the steam flow rate after iteration; is the target speed of the steam turbine, is the steam turbine speed before iteration, K P2 is the proportional gain, K i2 is the integral gain, and dτ is the time step.

5. A method for controlling the start-up parallel point of a combined cycle unit according to claim 4, characterized in that: In step three, associating the relevant physical model with the relevant iteration model, substituting the current operation parameters into the associated model for iteration, and generating a parallel point startup plan includes: S31, associating the gas turbine physical model with the gas turbine iterative model to form a gas turbine associated model; associating the steam turbine physical model with the steam turbine iterative model to form a steam turbine associated model; S32, when put into operation, the speed and flow rate in the initial state are substituted into the physical model of the gas turbine and the physical model of the steam turbine to obtain the speed ω of the gas turbine after a time step dτ GT (τ) and steam turbine speed ω ST (τ); S33, the gas turbine speed ω after a time step dτ GT (τ) and steam turbine speed ω ST (τ) is correspondingly substituted into the gas turbine iteration model and the steam turbine iteration model, replacing the gas turbine speed before iteration in the iteration model and the steam turbine speed before iteration S34, after the iterative model calculation, the fuel flow after a time step dτ is obtained and recorded and steam flow S35, the fuel flow after a time step dτ and steam flow Substitute it into the gas turbine physical model and the steam turbine physical model again, replace the fuel flow and steam flow in the physical model, calculate and record the gas turbine speed ω after the second time step 2dτ GT (2τ) and steam turbine speed ω ST (2τ); S36, the gas turbine speed ω after the second time step 2dτ GT (2τ) and steam turbine speed ω ST (2τ) is substituted into the iterative model again, replacing the gas turbine speed before iteration and the steam turbine speed before iteration Get and record the fuel flow rate after the second time step 2dτ and steam flow S37, repeat the above steps until and are all 0, and it is defined as steady state; record the number of time steps required for the gas turbine and steam turbine to reach steady state, as well as the fuel flow of the gas turbine at each time step and steam flow rate of steam turbine S38, generating an optimized parallel point startup plan based on the recorded content.

6. A method for controlling the start-up parallel point of a combined cycle unit according to claim 5, characterized in that: In step 4, the calculation and recording of the total energy consumption reduced by the parallel point startup scheme and the preset consumption reduction model includes: S41, pre-establishing an energy consumption calculation model for a common solution: Among them, E to (t) is the total energy consumption of the total time step under the general scheme, E GT (t) is the energy consumption of gas turbine under the common scheme, E ST (t) is the energy consumption of steam turbine under the common scheme, E loss (t) is the unit loss under the common scheme, and t is the total time period corresponding to the total time step; S42, establishing an energy consumption calculation model for the optimization scheme: in, is the energy consumption reduced by the optimized parallel point starting scheme compared with the ordinary scheme, E to (t) is the total energy consumption of the total time step under the common scheme, c1 is the first weight coefficient, c2 is the second weight coefficient, and t is the total time period corresponding to the total time step; S43, the energy consumption reduced by the optimized parallel point starting scheme compared with the ordinary scheme Recorded in the database.

7. A method for controlling the start-up parallel point of a combined cycle unit according to claim 6, characterized in that: Also includes: Energy consumption reduction based on the optimized parallel point startup scheme compared with the ordinary scheme Determine whether to adopt the optimized parallel point startup plan.

8. A method for controlling the start-up parallel point of a combined cycle unit according to claim 7, characterized in that: In step 5, the parallel point start-up plan is sent to the front-end device, and the actions of automatically controlling the unit according to the parallel point start-up plan include: Convert each time step in the parallel point start-up scheme into a time period, and associate the time period with the fuel flow rate of the gas turbine to which the time step corresponds and steam flow rate of steam turbine match; The fuel flow and steam flow of the gas turbine and steam turbine are controlled in each time period through the front-end equipment, and parallel point start-up is performed in the last time period.

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