Turbine bypass discharge system control method and system

Abstract

The present application relates to a turbine bypass exhaust system control method and system, the control method comprising: S101, obtaining turbine load, final power setting value and deaerator steam consumption; S102, calculating according to turbine load, final power setting value and deaerator steam consumption, obtaining two-loop load deviation; S103, obtaining the required opening of the turbine bypass exhaust system valve; S104, correcting the required opening based on the two-loop load deviation to obtain the target opening; S105, controlling the valve of the turbine bypass exhaust system according to the target opening. The present application fully considers the real load of the turbine at low power, the consumption source term of the main steam at transient condition, makes the control of the turbine bypass exhaust system more comprehensive, eliminates the ultra-high caused by vibration or even leads to unexpected events, ensures the energy balance of the primary loop and the secondary loop at low power condition, and also ensures the stability of the system regulation.

Description

Technical Field

[0001] This invention relates to the field of nuclear power turbine control technology, and more specifically, to a control method and system for a turbine bypass emission system. Background Technology

[0002] The turbine bypass venting system in a nuclear power plant primarily vents main steam directly to the condenser to allow the unit to adapt to rapid and significant changes in turbine load (such as load shedding) during power operation, reducing transient fluctuations in temperature and pressure in the nuclear steam supply system (NSSS). Under low-power conditions, the turbine bypass venting system also plays a crucial role in stabilizing secondary side pressure and balancing the primary and secondary loop energy. However, current turbine bypass venting systems cannot guarantee energy balance between the primary and secondary loops under low-power conditions, and their regulation is also unstable. Therefore, turbine venting system control plays a vital role in the stability of the unit's state at different power levels under various operating conditions. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a control method and system for a steam turbine bypass emission system, addressing the problems existing in the prior art.

[0004] The technical solution adopted by this invention to solve its technical problem is: to construct a control method for a steam turbine bypass emission system, comprising the following steps:

[0005] S101. Obtain the turbine load, final power set value, and deaerator steam consumption;

[0006] S102. Calculate the second loop load deviation based on the turbine load, the final power setting value, and the deaerator steam consumption.

[0007] S103. Obtain the required opening degree of the valves in the turbine bypass discharge system;

[0008] S104. Based on the load deviation of the two circuits, the demand opening is corrected to obtain the target opening.

[0009] S105. Control the valves of the turbine bypass discharge system according to the target opening degree.

[0010] In the turbine bypass emission system control method of the present invention, step S101 includes:

[0011] Collect the first-stage inlet steam pressure signal of the steam turbine;

[0012] The load calculation value is obtained by calculating based on the turbine first-stage inlet steam pressure signal;

[0013] Obtain the preset load of the steam turbine;

[0014] The turbine load is determined based on the turbine trip signal, the calculated load value, and the preset load.

[0015] In the turbine bypass discharge system control method of the present invention, determining the turbine load based on the turbine trip signal, the calculated load value, and the preset load includes:

[0016] Determine whether the turbine trip signal has been triggered;

[0017] If the turbine trip signal is not triggered, the calculated load value is taken as the turbine load.

[0018] If the turbine trip signal is triggered, the preset load will be used as the turbine load.

[0019] In the turbine bypass emission system control method of the present invention, step S101 includes:

[0020] Obtain the status of the main regulating valve and the stack / unit status of the turbine bypass discharge system;

[0021] The final power setting value is determined based on the status of the main regulating valve and the status of the reactor / unit.

[0022] In the turbine bypass emission system control method of the present invention, the main regulating valve state includes: an unclosed state and a closed state; the reactor / unit state includes: reactor tripping without turbine tripping state and turbine tripping without reactor tripping state.

[0023] Step S101 includes:

[0024] If the main regulating valve is in an open state, the final power setting value will be the target power setting value obtained in the pressure control mode.

[0025] If the main control valve is in the closed state and the stack / machine state is in the stack-skipping-but-not-skipping-machine state, then the final power setting value is 0%FP;

[0026] If the main regulating valve is in the closed state and the reactor / machine state is in the tripped-but-not-tripped-reactor state, then the final power setting value is ≤30%FP.

[0027] In the turbine bypass emission system control method of the present invention, the second loop load deviation includes: a first load deviation value and a second load deviation value;

[0028] Step S102 includes:

[0029] The first load deviation value is obtained by calculating based on the turbine load and the final power setting value;

[0030] The second load deviation value is obtained based on the steam consumption of the deaerator.

[0031] In the turbine bypass emission system control method of the present invention, step S103 includes:

[0032] Obtain the maximum average temperature of the primary loop;

[0033] The primary control target temperature is obtained by calculating based on the turbine load and the final power setting value;

[0034] The temperature deviation of the first loop is calculated based on the maximum average temperature of the first loop and the target temperature of the first loop control.

[0035] The required opening degree is obtained by calculating based on the temperature deviation of the first loop.

[0036] In the turbine bypass emission system control method of the present invention, step S104 includes:

[0037] A first correction value is obtained by calculating based on the first load deviation value;

[0038] The second correction value is obtained by calculating based on the second load deviation value;

[0039] The demand opening is adjusted using the first correction value and the second correction value to obtain the target opening.

[0040] The present invention also provides a control system for a steam turbine bypass emission system, comprising:

[0041] The parameter acquisition unit is used to acquire the turbine load, final power set value, and deaerator steam consumption.

[0042] The load deviation calculation unit is used to calculate the second loop load deviation based on the turbine load, the final power setting value, and the deaerator steam consumption.

[0043] Demand opening acquisition unit is used to acquire the demand opening of the valves in the turbine bypass discharge system;

[0044] The opening correction unit is used to correct the demand opening based on the load deviation of the two circuits to obtain the target opening.

[0045] The control unit is used to control the valves of the turbine bypass discharge system according to the target opening degree.

[0046] In the turbine bypass emission system control system of the present invention, the parameter acquisition unit includes: a turbine load acquisition module;

[0047] The turbine load acquisition module is used for:

[0048] Collect the first-stage inlet steam pressure signal of the steam turbine;

[0049] The load calculation value is obtained by calculating based on the turbine first-stage inlet steam pressure signal;

[0050] Obtain the preset load of the steam turbine;

[0051] The turbine load is determined based on the turbine trip signal, the calculated load value, and the preset load.

[0052] In the turbine bypass emission system control system of the present invention, the parameter acquisition unit further includes: a power acquisition module;

[0053] The power acquisition module is used for:

[0054] Obtain the status of the main regulating valve and the stack / unit status of the turbine bypass discharge system;

[0055] The final power setting value is determined based on the status of the main regulating valve and the status of the reactor / unit.

[0056] In the turbine bypass emission system control system of the present invention, the load deviation calculation unit includes:

[0057] The first load deviation calculation module is used to calculate the first load deviation value based on the turbine load and the final power setting value.

[0058] The second load deviation determination module is used to obtain the second load deviation value based on the steam consumption of the deaerator.

[0059] In the turbine bypass emission system control system of the present invention, the demand opening unit includes:

[0060] Temperature acquisition module, the temperature acquisition module is used to acquire the maximum average temperature of the primary loop;

[0061] The target temperature calculation module is used to calculate the primary control target temperature based on the turbine load and the final power setting value.

[0062] A temperature deviation calculation module is used to calculate the temperature deviation of the first loop based on the maximum average temperature of the first loop and the target temperature of the first loop control.

[0063] The demand opening calculation module is used to calculate the demand opening based on the temperature deviation of the first loop.

[0064] In the turbine bypass emission system control system of the present invention, the opening correction unit includes:

[0065] The first correction value calculation module is used to calculate the first correction value based on the first load deviation value.

[0066] The second correction value calculation module is used to calculate the second correction value based on the second load deviation value.

[0067] The correction module is used to correct the demand opening degree using the first correction value and the second correction value to obtain the target opening degree.

[0068] The turbine bypass emission system control method and system of the present invention have the following beneficial effects: The present invention fully considers the actual load of the turbine under low power and the main steam consumption sources under transient conditions, making the control vibration of the turbine bypass emission system more comprehensive, eliminating the excessive vibration or even causing unexpected events, ensuring the energy balance of the first and second loops under low power conditions, and also ensuring the stability of system regulation. Attached Figure Description

[0069] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0070] Figure 1 This is a schematic flowchart of the turbine bypass emission system control method provided in an embodiment of the present invention;

[0071] Figure 2 This is a schematic diagram of the turbine load acquisition process provided in an embodiment of the present invention;

[0072] Figure 3 This is a schematic diagram of the process for obtaining the final power setting value provided in an embodiment of the present invention;

[0073] Figure 4 This is a flowchart of the two-loop load deviation calculation provided in an embodiment of the present invention;

[0074] Figure 5 This is a flowchart illustrating the process of obtaining the required opening degree of the valve in the turbine bypass discharge system provided in an embodiment of the present invention.

[0075] Figure 6 This is a simplified diagram of the control process of the valves in the turbine bypass emission system under low power conditions provided in an embodiment of the present invention;

[0076] Figure 7 This is a logic block diagram of the turbine bypass emission system control system provided in an embodiment of the present invention. Detailed Implementation

[0077] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0078] This invention fully considers the actual load of the turbine under low-power conditions and the main steam consumption sources under transient conditions in nuclear power plants. It also considers the consumption of main steam by the feedwater deaerator under low-power conditions. The original control scheme is optimized from the process analysis process, control scheme and model, and control process (function / disturbance). This makes the control disturbance of the turbine bypass emission system more comprehensive, eliminates overshoot caused by disturbance and even unexpected events caused by it, and solves the problems of nuclear power exceeding expectations and core overheating under low power conditions.

[0079] In a preferred embodiment, such as Figure 1 The overall flow chart of the turbine bypass emission system control method provided by this invention is shown. This turbine bypass emission system control method can be applied to the bypass emission system control when the primary and secondary loops are unbalanced under low-power operating conditions in nuclear power plants. Low-power operating conditions generally refer to operating conditions where nuclear power is between 0%FP and 30%FP.

[0080] Specifically, such as Figure 1 As shown, the control method for the turbine bypass emission system includes the following steps:

[0081] Step S101: Obtain the turbine load (Pn), final power setting value (Pn0), and deaerator steam consumption (Q).

[0082] Optionally, in some embodiments, such as Figure 2 As shown, the turbine load can be obtained through the following steps:

[0083] Step S201: Acquire the first-stage inlet steam pressure signal of the steam turbine. It should be noted that if there are multiple pressure signals, the second largest value among these pressure signals is generally selected as the first-stage inlet steam pressure signal of the steam turbine.

[0084] Step S202: Calculate the load value based on the steam turbine first-stage inlet steam pressure signal.

[0085] The calculation process for the load calculation value is as follows: The turbine load is generally provided to the user by the turbine manufacturer in the form of a theoretical curve of turbine first-stage inlet pressure versus turbine power (including data sets for different power points of the turbine). However, information on the theoretical curve (data set) under low-power conditions is missing. The user can use the two sets of data with the lowest theoretical power values ​​from the theoretical curve (data set) provided by the turbine manufacturer to perform linear function fitting, obtaining the turbine load function Y=mX+n corresponding to the first-stage inlet pressure under low-power conditions, where Y represents the turbine load Pn, X represents the first-stage inlet pressure, and m and n represent constants in the fitting function. Therefore, the data set under low power is calculated based on this turbine load function, and together with the data set provided by the turbine manufacturer, a complete 0-120%FP power range and corresponding inlet pressure are formed.

[0086] Step S203: Obtain the preset load of the steam turbine.

[0087] Optionally, the preset load of the steam turbine is the load when the steam turbine trips, which is generally 0.

[0088] Step S204: Determine the turbine load based on the turbine trip signal, the calculated load value, and the preset load.

[0089] Optionally, determining the turbine load based on the turbine trip signal, the calculated load value, and the preset load includes: determining whether the turbine trip signal has been triggered; if the turbine trip signal has not been triggered, then the calculated load value is used as the turbine load; if the turbine trip signal has been triggered, then the preset load is used as the turbine load. Specifically, when the turbine is not tripped, the turbine load is the calculated load value; when the turbine trips, the turbine load is the preset load.

[0090] Based on the actual operating conditions of the steam turbine, this invention obtains the turbine load before and after the turbine trips, making the overall turbine load under low-power conditions closer to the actual turbine load.

[0091] Optionally, step S101 includes: acquiring the status of the main regulating valve of the turbine bypass discharge system and the reactor / unit status; and determining the final power setpoint based on the main regulating valve status and the reactor / unit status. The main regulating valve status includes: an open state and a closed state; the reactor / unit status includes: a reactor trip without tripping the turbine and a turbine trip without tripping the reactor. In some embodiments, if the main regulating valve is in an open state, the final power setpoint is determined by the target power setpoint acquired under pressure control mode; if the main regulating valve is in a closed state and the reactor / unit status is a reactor trip without tripping the turbine, the final power setpoint is 0%FP; if the main regulating valve is in a closed state and the reactor / unit status is a turbine trip without tripping the reactor, the final power setpoint is ≤30%FP.

[0092] It should be noted that the concept and significance of the final power setpoint is as follows: When the turbine bypass emission system is running, the turbine inlet steam pressure signal cannot represent the total load of the secondary loop. In this case, a power value is artificially set as the target for the turbine bypass emission system and reactor power control; this is called the final power setpoint. This invention focuses on the control scheme of the turbine bypass emission system; therefore, the final power setpoint in this embodiment is used as an important parameter for balancing the primary and secondary loop energy under low power conditions in the turbine bypass emission system.

[0093] As mentioned earlier, the reactor (pressurized water reactor) and turbine (nuclear power unit) states and operating conditions differ under low-power conditions, resulting in different methods and results for obtaining the final power setting value. In some embodiments, Figure 3 The process of obtaining the final power setting value is shown. Combined with... Figure 3 The final power setting values ​​under different modes and operating conditions are explained respectively.

[0094] In pressure control mode (P mode), the final power setpoint is a manually set final power setpoint function, namely GD(P).

[0095] In non-pressure control mode (non-P mode), the final power setpoint when the turbine trips but does not trip the reactor is ≤30%FP. When the turbine load is greater than or equal to 30%FP, the final power setpoint is 30%; when the turbine load is less than 30%FP, the final power setpoint is the current turbine load. That is, the smaller value between the turbine load and 30%FP is taken.

[0096] The final power setting value under either reactor skipping or non-stack skipping conditions is 0%FP.

[0097] The final power setting values ​​obtained in the above three scenarios also need to be selected in conjunction with the status of the main regulating valve of the turbine bypass discharge system. Specifically: when the main regulating valve of the turbine bypass discharge system is not closed, the final power setting value of the turbine bypass discharge system participating in balancing the energy of the primary and secondary loops and the load deviation of the secondary loop is the final power setting value GD(P) obtained in P mode; when the main regulating valve of the turbine bypass discharge system is closed, the final power setting value of the turbine bypass discharge system participating in balancing the energy of the primary and secondary loops and the load deviation of the secondary loop under reactor trip or no trip is 0%FP; when the main regulating valve of the turbine bypass discharge system is closed, the final power setting value of the turbine bypass discharge system participating in balancing the energy of the primary and secondary loops and the load deviation of the secondary loop under non-P mode under trip or no reactor trip is ≤30%FP.

[0098] Step S102: Calculate the load deviation of the secondary loop based on the turbine load, final power setting value and deaerator steam consumption.

[0099] Optionally, the load deviation of the secondary loop includes: a first load deviation value and a second load deviation value. Step S102 includes: calculating the first load deviation value based on the turbine load and the final power setting value; and obtaining the second load deviation value based on the deaerator steam consumption.

[0100] The secondary loop load deviation serves as a valve control feedforward signal to correct the energy balance between the primary and secondary loops. It is used to adjust the demand opening of the turbine bypass discharge system, which balances the energy of the primary and secondary loops. It should be noted that the secondary loop load needs to be balanced because the manually set load—the final power setpoint—of the secondary loop must be balanced with the turbine load, deaerator load, and turbine bypass discharge system load that consume energy from the secondary loop. This prevents overpressure in the secondary loop from triggering other safety system equipment or even causing unexpected turbine or reactor trips.

[0101] In some embodiments, combined with Figure 4 The acquisition of the first and second load deviation values ​​is explained below. The first load deviation value is obtained as follows: First, based on the turbine load Pn, final power set value Pn0, and feedwater deaerator steam consumption Q obtained in step S101; then, the first load deviation value is calculated based on the turbine load Pn and final power set value Pn0: ΔP1 = Pn0 - Pn. Next, the temperature deviation ΔT1 corresponding to the first load deviation value is obtained through conversion calculation using the ΔT1(ΔP1) function (GD2). The second load deviation value is obtained as follows: In this embodiment of the invention, the feedwater deaerator steam consumption Q can be directly used as part of the energy balance requirement of the secondary loop, i.e., the second deviation value: ΔP2 = Q. By calculating the first and second load deviation values, it can be determined that the total load deviation in the secondary loop requires the turbine bypass discharge system regulating valve to open or close by a certain degree to respond to the energy balance requirement of the secondary loop.

[0102] Step S103: Obtain the required opening degree of the turbine bypass discharge system valve.

[0103] Optionally, in some embodiments, step S103 includes: obtaining the maximum value of the primary loop average temperature; calculating the primary loop control target temperature based on the turbine load and the final power setting value; calculating the primary loop temperature deviation based on the primary loop average temperature and the primary loop control target temperature; and calculating the required opening degree based on the primary loop temperature deviation.

[0104] refer to Figure 5 , Figure 5 The process for obtaining the demand switch for a turbine bypass discharge system that balances the energy of the primary and secondary loops is presented. It should be noted that valve control in the turbine bypass discharge system refers to the control process in which the turbine bypass discharge system participates in balancing the energy of the primary and secondary loops. For example... Figure 5As shown, the specific steps for obtaining the demand level are as follows:

[0105] First, obtain the maximum average temperature of the first loop, TavgMAX;

[0106] Next, select the larger value between the turbine load Pn obtained in step S101 and the final power setting value Pn0;

[0107] Then, based on this larger value, it is converted into a first-loop control target temperature Tref through a first-loop target temperature conversion function (GD1).

[0108] The specific expression for GD1 is as follows:

[0109] GD1=0.74*(MAX(Pn,Pn0))+120.

[0110] Based on the above formula, the target temperature Tref for the first-loop control can be obtained, that is, Tref = GD1 = 0.74 * (MAX(Pn,Pn0)) + 120.

[0111] Next, the maximum average temperature of the first loop, TavgMAX, is subtracted from the target temperature of the first loop, Tref, to obtain the temperature deviation of the first loop, i.e., ΔTref=TavgMAX-Tref.

[0112] Finally, based on the primary loop temperature deviation, and combined with the primary loop temperature deviation ΔTref - turbine bypass discharge system regulating valve total opening conversion function (GD4), the corresponding demand opening, i.e., the demand opening (A) of the turbine bypass discharge system, is obtained.

[0113] The specific expression for GD4 is as follows:

[0114] GD4 = A (total valve opening requirement). Its specific values ​​are: when ΔTref∈[-5,-3], GD4=15*ΔTref+45; when ΔTref∈(-3,3), GD4=0; when ΔTref∈[3,13], GD4=10*ΔTref-30.

[0115] The demand opening obtained by the above process, when applied to the turbine load calculation function Y=mx+n under low power conditions, can more realistically reflect the energy demand of the secondary loop under low power conditions (≤30%FP). The energy deviation (ΔTref) between the primary and secondary loops is also closer to the excess energy that needs to be discharged by the turbine bypass emission system. Moreover, this scheme has been applied and verified in engineering practice.

[0116] Step S104: Based on the load deviation of the second circuit, the demand opening is corrected to obtain the target opening.

[0117] Optionally, step S104 includes: calculating a first correction value based on a first load deviation value; calculating a second correction value based on a second load deviation value; and correcting the demand opening degree using the first correction value and the second correction value to obtain the target opening degree.

[0118] Specifically, based on the aforementioned calculated ΔT1, and combined with the ΔT1-turbine bypass discharge system regulating valve opening conversion function (GD3), the feedforward correction 1 caused by the second loop load deviation, i.e., the first correction value a1, can be obtained. Alternatively, in some other embodiments, considering that the calculation result of the known second loop energy balance correction 1 from ΔP1 to a1 is actually a superposition of the calculation processes of GD2 and GD3, and the final linearity of GD2 and GD3 calculated by engineering modeling is a fixed constant H, that is, the second loop energy to be balanced and the valve opening requirement of the turbine bypass system are linearly related. Therefore, we can have: a1=H*ΔP1. Where, a1 is the first correction value.

[0119] As mentioned above, the second load deviation value is ΔP2 = Q. The final linearity H of GD2 and GD3 still applies to the valve opening requirement of the turbine bypass system corresponding to the energy ΔP2 requiring two-loop balance, i.e., steam consumption Q. Therefore, we have: a2 = H * ΔP2 = H * Q, where a2 is the first correction value. After calculating a1 and a2, the required opening can be corrected to obtain the target opening. The calculation process for the target opening is: %open = A + (a1 - a2), where %open is the target opening.

[0120] The specific expression for GD2 is as follows:

[0121] GD2 = ΔT1 = 13 * ΔP1;

[0122] The specific expression for GD3 is shown below:

[0123] GD3=a1=0.067*ΔT1.

[0124] The calculation for the fixed constant is as follows:

[0125] Based on GD2=ΔT1=13*ΔP1 and GD3=a1 (valve correction opening)=0.067*ΔT1, we get GD3=a1=0.067*GD2=0.871ΔP1. Since ΔP1 represents the load deviation of the second loop, and the steam consumption Q of the feedwater deaeration system also represents the load deviation of the second loop, the valve opening correction function caused by the steam consumption Q of the feedwater deaeration system is essentially still GD3. However, for the steam consumption Q of the feedwater deaeration system, Q is a variable in GD3, meaning the valve opening correction caused by Q is a2=GD3=0.871Q, and 0.871 is H. It should be noted that 0.871 is only used as an example. In actual applications, the specific value of H will be adjusted according to changes in actual parameters.

[0126] In this embodiment of the invention, the valve opening correction 2, i.e., the second correction value a2, obtained by measuring the effect of the steam consumption Q of the feedwater deaerator on the valve opening of the turbine bypass discharge system, shows that the invention fully considers other possible main steam consumption sources in the secondary loop besides the turbine load. It provides a detailed description of the process flow requirements, control scheme, and implementation details, and conforms as much as possible to the control process of energy balance in the secondary loop. Moreover, this implementation scheme has been successfully verified in engineering projects.

[0127] Step S105: Control the valves of the turbine bypass discharge system according to the target opening degree.

[0128] After the target opening degree is calculated in step S104, the valves of the turbine bypass discharge system can be controlled accordingly based on the target opening degree.

[0129] Specifically, in combination Figure 6 The valve control process of the turbine bypass emission system under low power conditions of the present invention is described.

[0130] like Figure 6 As shown, the details are as follows:

[0131] Get the turbine load Pn, get the final power set value Pn0, and get the maximum real-time average temperature of the primary loop TavgMAX.

[0132] The primary loop target temperature Tref is calculated based on the greater of the turbine load Pn and the final power setting value Pn0.

[0133] The temperature control deviation ΔTref of the first loop is calculated based on the maximum real-time average temperature of the first loop, TavgMAX, and the target temperature of the first loop, Tref.

[0134] The required opening degree A of the regulating valve of the turbine bypass system for balancing the energy of the primary and secondary loops is calculated based on the primary loop temperature control deviation ΔTref.

[0135] The load deviation ΔP1 of the second loop is calculated based on the difference between the turbine load Pn and the final power setting value Pn0, and then converted into the turbine bypass system regulating valve opening correction 1 (first correction value a1).

[0136] The correction 2 (second correction value a2) to the opening of the regulating valve of the turbine bypass system is calculated based on the steam consumption of the feedwater deaerator.

[0137] Based on the opening requirement A of the turbine bypass system regulating valve for balancing the energy of the primary and secondary loops, and the first correction value a1 and the second correction value a2 of the opening of the turbine bypass system regulating valve for balancing the load deviation of the secondary loop, the final required opening of the regulating valve of the turbine bypass discharge system, i.e. the target opening, is obtained: %open=A+(a1-a2).

[0138] Finally, the regulating valve of the turbine bypass discharge system is controlled according to the target opening degree.

[0139] This invention obtains a turbine load closer to the actual steam consumption of the turbine under low-power operating conditions through a turbine load calculation function. By adding the secondary loop steam consumption source outside the turbine—the feedwater deaerator—the secondary loop load is consumed. Therefore, when performing primary and secondary loop energy balance and secondary loop load deviation correction based on this turbine load, the total valve opening that needs to be increased or decreased in the turbine bypass discharge system under low power conditions is obtained more accurately. This allows the turbine bypass discharge system to respond more precisely and quickly to the primary and secondary loop energy balance requirements, avoiding primary and secondary loop energy imbalance, unstable bypass system regulation, and even unexpected reactor tripping events under low-power conditions.

[0140] refer to Figure 7 The present invention also provides a control system for a steam turbine bypass emission system.

[0141] In a preferred embodiment, such as Figure 7 As shown, the control system of the turbine bypass emission system includes:

[0142] The parameter acquisition unit 701 is used to acquire the turbine load, final power setting value and deaerator steam consumption.

[0143] Optionally, the parameter acquisition unit 701 includes: a turbine load acquisition module; the turbine load acquisition module is used to: acquire the turbine first-stage inlet steam pressure signal; calculate the load calculation value based on the turbine first-stage inlet steam pressure signal; acquire the turbine's preset load; and determine the turbine load based on the turbine trip signal, the load calculation value, and the preset load.

[0144] Optionally, the parameter acquisition unit 701 further includes a power acquisition module; the power acquisition module is used to: acquire the status of the main regulating valve of the turbine bypass discharge system and the status of the reactor / unit; and determine the final power setting value based on the status of the main regulating valve and the status of the reactor / unit.

[0145] The load deviation calculation unit 702 is used to calculate the load deviation of the secondary loop based on the turbine load, the final power setting value and the steam consumption of the deaerator.

[0146] Optionally, the load deviation calculation unit 702 includes: a first load deviation calculation module, which is used to calculate based on the turbine load and the final power setting value to obtain a first load deviation value; and a second load deviation determination module, which is used to obtain a second load deviation value based on the deaerator steam consumption.

[0147] The demand opening acquisition unit 703 is used to acquire the demand opening of the valves in the turbine bypass discharge system.

[0148] Optionally, the demand opening unit 703 includes: a temperature acquisition module for acquiring the maximum value of the primary loop average temperature; a target temperature calculation module for calculating the primary loop control target temperature based on the turbine load and final power setting value; a temperature deviation calculation module for calculating the primary loop temperature deviation based on the maximum value of the primary loop average temperature and the primary loop control target temperature; and a demand opening calculation module for calculating the demand opening based on the primary loop temperature deviation.

[0149] The opening correction unit 704 is used to correct the demand opening based on the load deviation of the second circuit to obtain the target opening.

[0150] Optionally, the opening correction unit 704 includes: a first correction value calculation module, which is used to calculate based on a first load deviation value to obtain a first correction value; a second correction value calculation module, which is used to calculate based on a second load deviation value to obtain a second correction value; and a correction module, which is used to correct the demand opening through the first correction value and the second correction value to obtain a target opening.

[0151] Control unit 705 is used to control the valves of the turbine bypass discharge system according to the target opening degree.

[0152] Specifically, the specific coordination and operation process between the various units in the turbine bypass emission system control system can be referred to the turbine bypass emission system control method described above, and will not be repeated here.

[0153] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0154] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0155] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented directly by hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0156] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They do not limit the scope of protection of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention should fall within the scope of the claims of the present invention.

Claims

1. A control method for a steam turbine bypass emission system, characterized in that, Includes the following steps: S101. Obtain the turbine load, final power set value, and deaerator steam consumption; S102. Calculate the second loop load deviation based on the turbine load, the final power setting value, and the deaerator steam consumption. S103. Obtain the required opening degree of the valves in the turbine bypass discharge system; S104. Based on the load deviation of the two circuits, the required opening degree is corrected to obtain the target opening degree; S105. Control the valves of the turbine bypass discharge system according to the target opening degree.

2. The control method for a steam turbine bypass emission system according to claim 1, characterized in that, Step S101 includes: Collect the first-stage inlet steam pressure signal of the steam turbine; The load calculation value is obtained by calculating based on the turbine first-stage inlet steam pressure signal; Obtain the preset load of the steam turbine; The turbine load is determined based on the turbine trip signal, the calculated load value, and the preset load.

3. The control method for a steam turbine bypass emission system according to claim 2, characterized in that, The step of determining the turbine load based on the turbine trip signal, the calculated load value, and the preset load includes: Determine whether the turbine trip signal has been triggered; If the turbine trip signal is not triggered, the calculated load value is taken as the turbine load. If the turbine trip signal is triggered, the preset load will be used as the turbine load.

4. The control method for a steam turbine bypass emission system according to claim 1, characterized in that, Step S101 includes: Obtain the status of the main regulating valve and the stack / unit status of the turbine bypass discharge system; The final power setting value is determined based on the status of the main regulating valve and the status of the reactor / unit.

5. The control method for a steam turbine bypass emission system according to claim 4, characterized in that, The main control valve status includes: not closed and closed; the stack / unit status includes: stack trip without unit trip and unit trip without stack trip. Step S101 includes: If the main regulating valve is in an open state, the final power setting value will be the target power setting value obtained in the pressure control mode. If the main control valve is in the closed state and the stack / unit is in the state of tripping the stack but not tripping the unit, then the final power setting value is 0%FP; If the main regulating valve is in the closed state and the reactor / unit is in the tripped but not tripped state, then the final power setting value is ≤30%FP.

6. The control method for a steam turbine bypass emission system according to claim 1, characterized in that, The load deviation of the two circuits includes: a first load deviation value and a second load deviation value; Step S102 includes: The first load deviation value is obtained by calculating based on the turbine load and the final power setting value; The second load deviation value is obtained based on the steam consumption of the deaerator.

7. The control method for a steam turbine bypass emission system according to claim 1, characterized in that, Step S103 includes: Obtain the maximum average temperature of the primary loop; The primary control target temperature is obtained by calculating based on the turbine load and the final power setting value; The temperature deviation of the first loop is calculated based on the maximum average temperature of the first loop and the target temperature of the first loop control. The required opening degree is obtained by calculating based on the temperature deviation of the first loop.

8. The control method for a steam turbine bypass emission system according to claim 6, characterized in that, Step S104 includes: A first correction value is obtained by calculating based on the first load deviation value; The second correction value is obtained by calculating based on the second load deviation value; The demand opening is adjusted using the first correction value and the second correction value to obtain the target opening.

9. A control system for a steam turbine bypass emission system, characterized in that, include: The parameter acquisition unit is used to acquire the turbine load, final power set value, and deaerator steam consumption. The load deviation calculation unit is used to calculate the second loop load deviation based on the turbine load, the final power setting value, and the deaerator steam consumption. Demand opening acquisition unit is used to acquire the demand opening of the valves in the turbine bypass discharge system; An opening correction unit is used to correct the required opening based on the load deviation of the two circuits to obtain the target opening. The control unit is used to control the valves of the turbine bypass discharge system according to the target opening degree.

10. The turbine bypass emission system control system according to claim 9, characterized in that, The parameter acquisition unit includes: a steam turbine load acquisition module; The turbine load acquisition module is used for: Collect the first-stage inlet steam pressure signal of the steam turbine; The load calculation value is obtained by calculating based on the turbine first-stage inlet steam pressure signal; Obtain the preset load of the steam turbine; The turbine load is determined based on the turbine trip signal, the calculated load value, and the preset load.

11. The turbine bypass emission system control system according to claim 9, characterized in that, The parameter acquisition unit further includes: a power acquisition module; The power acquisition module is used for: Obtain the status of the main regulating valve and the stack / unit status of the turbine bypass discharge system; The final power setting value is determined based on the status of the main regulating valve and the status of the reactor / unit.

12. The turbine bypass emission system control system according to claim 9, characterized in that, The load deviation calculation unit includes: The first load deviation calculation module is used to calculate the first load deviation value based on the turbine load and the final power setting value. The second load deviation determination module is used to obtain a second load deviation value based on the steam consumption of the deaerator.

13. The turbine bypass emission system control system according to claim 9, characterized in that, The demand opening degree acquisition unit includes: Temperature acquisition module, the temperature acquisition module is used to acquire the maximum average temperature of the primary loop; The target temperature calculation module is used to calculate the primary control target temperature based on the turbine load and the final power setting value. A temperature deviation calculation module is used to calculate the temperature deviation of the first loop based on the maximum average temperature of the first loop and the target temperature of the first loop control. The demand opening calculation module is used to calculate the demand opening based on the temperature deviation of the first loop.

14. The turbine bypass emission system control system according to claim 9, characterized in that, The aperture correction unit includes: The first correction value calculation module is used to calculate and obtain the first correction value based on the first load deviation value. The second correction value calculation module is used to calculate and obtain the second correction value based on the second load deviation value. The correction module is used to correct the demand opening degree using the first correction value and the second correction value to obtain the target opening degree.

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