Decoupling control method and system for thermal lag first peak of temperature and pressure reduction system

Abstract

The invention relates to a temperature and pressure reduction system thermal lag first peak decoupling control method and system, and belongs to the technical field of thermotechnical automation, the method realizes decoupling through the following steps: determining the start and end time of a first wave window, and establishing a safety envelope according to an allowable temperature change rate, a pressure change rate, a minimum nozzle pressure difference and a material thermal shock limit; a pressure forming main track and a temperature following auxiliary track are constructed, and peak shifting cooperation of pressure forming first and temperature following second is achieved through three-section design of a starting gentle slope, linear climbing and converging; a gating signal is generated based on nozzle differential pressure continuous monitoring and valve side slope convergence, and it is ensured that the water side participates only when atomization is effective; a limited micro-correction increment is calculated, envelope projection is implemented, and the action is maintained within a safety boundary; and when the temperature and pressure change rate reaches a steady-state threshold, smoothly transferring to conventional control. The method obviously reduces the head wave temperature overshoot and pressure disturbance, improves the equipment reliability, and is suitable for high-dynamic scenes such as boiler start-stop and bypass.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of thermal automation, more particularly, to a thermal lag first peak decoupling control method and system for a desuperheating and pressure reducing system. BACKGROUND

[0002] As a key component of a thermal system, a desuperheating and pressure reducing system (PRDS) is widely used in the processes of boiler start-stop, bypass and load switching. Its core function is to adjust high-temperature and high-pressure steam to the required pressure and temperature parameters in the downstream by means of a desuperheating and pressure reducing valve cooperating with a nozzle water injection. However, in the first wave stage of system start-stop, the steam side pressure responds quickly and the temperature responds slowly, and there is a significant thermal lag phenomenon. At the same time, the water side atomization and evaporation effect is constrained by the nozzle pressure difference, water supply stability and downstream gas phase conditions. If the control is not proper, it is easy to cause unevaporated water to enter the downstream, temperature overshoot, pressure disturbance and material thermal shock risk. Such problems not only affect the stability of the system, but also may damage the pressure equipment and pipelines due to the change rate of temperature and pressure exceeding the limit, and shorten the service life of the equipment.

[0003] The existing technology mostly adopts a pressure-temperature cascade control scheme, that is, the PRDS valve on the steam side tracks the downstream pressure setpoint, and the water side tracks the temperature setpoint by means of injection amount or valve opening degree, and is assisted by steam flow feedforward, soft start slope, rate limiting and other decentralized means. For example, some systems improve dynamic performance by model prediction or gain scheduling, or adopt hierarchical injection and secondary nozzle structure. However, such methods have inherent defects: the time sequence of "pressure shaping-temperature following" is not explicitly distinguished in the first wave window, which may cause the water side to participate when the nozzle pressure difference is not fully established, or overlap with the large slope action stage of the valve side, causing control mismatch; the constraint conditions are usually realized by decentralized limiting, and are not integrated into a unified actionable space, so the micro-correction and gating are not strongly bound, and may easily jitter or mismatch when the boundary is adjacent; there is no convergence and freezing mechanism at the end of the window, and it is difficult to smoothly hand over to the regular control. SUMMARY

[0004] To solve the above technical problems, the present application provides a thermal lag first peak decoupling control method and system for a desuperheating and pressure reducing system.

[0005] The technical scheme of the present application is as follows: The present application provides a thermal lag first peak decoupling control method for a desuperheating and pressure reducing system, comprising the following steps: determining the start and end time of the first wave window of the desuperheating and pressure reducing system, and establishing a safety envelope according to the allowed temperature change rate, pressure change rate, nozzle minimum pressure difference and material thermal shock limit to obtain the first wave window parameters, envelope threshold and steady-state threshold; Based on the first wave window parameters and envelope threshold, the pressure forming main trajectory and temperature following secondary trajectory are constructed. The pressure forming main trajectory is divided into three segments: starting slope, linear climb and convergence. The overlap area duration and phase difference are set to obtain the valve baseline command and water-side baseline command. Based on the valve baseline command and the water side baseline command, monitor the nozzle pressure difference and the slope of the pressure forming main trajectory to ensure that they meet the preset conditions, and output a gating signal for effective atomization gating; Based on the gate signal and the temperature and pressure deviation downstream of the de-cooling and de-pressure reduction system, the micro-correction increment is calculated and limited within the safety envelope; The micro-correction increment is synthesized with the valve baseline command and the water-side baseline command, and the synthesis result is subjected to envelope projection to maintain the peak-shifting structure. The synthesized command is output to drive the actual operation of the desuperheating and pressure-reducing valve and the injection device. Monitor the rate of change of temperature and pressure downstream of the de-cooling and de-pressure reduction system, and shut down the gate control and hand over to normal control when the steady-state threshold is reached.

[0006] To facilitate understanding of this technical solution, some terms are explained in detail below: The initial window determination is the process of determining the steam branch from a stationary state to a controlled transition stage based on the start-stop trigger identification. The start and end of the first wave window include the start and end points of the first wave window. The start point is the start / stop trigger time, and the end point is the moment when the rate of change of downstream inlet temperature and the rate of change of downstream inlet pressure do not exceed the steady-state threshold and remain there for a predetermined time. The allowable rate of temperature change refers to the upper limit of the downstream inlet temperature change per unit time, including the upper limit of temperature rise and the upper limit of temperature fall. The permissible rate of pressure change refers to the upper limit of the allowable change in downstream inlet pressure per unit time; Material thermal shock limits are a set of limitations on the temperature gradient, rate of temperature change, and temperature difference that pressure-bearing equipment and pipelines can withstand. The parameters for the first wave window include the start and end dates of the first wave window, the duration of the first wave window, and the stage division threshold. The envelope thresholds include the upper temperature limit, the upper pressure limit, the allowable rate of temperature change, the allowable rate of pressure change, and the minimum pressure difference of the nozzle; The steady-state threshold is a threshold pair of temperature change rate and pressure change rate used to determine the end of the first wave window; The segmented timing script is a set of time sequences used to drive the PRDS desuperheating and pressure reducing valve and the water-side actuator within the first wave window, including the pressure forming main trajectory and the temperature following sub-trajectory. The pressure forming main trajectory is the target time series for the opening degree of the PRDS desuperheating and pressure reducing valve; the temperature following secondary trajectory is the target time series for the water injection volume or water valve opening. The initial gentle slope is the first small-slope climbing zone of the main pressure forming trajectory; linear climb is a second segment of the pressure forming main trajectory with constant slope; converge is a third segment of the pressure forming main trajectory with gradually decreasing slope; maximum increment of each segment is the upper limit of total change of opening or flow rate allowed in each segment; maximum slope is the upper limit of change per unit time allowed in each segment; overlap duration is the duration of time that the temperature following sub-trajectory is allowed to coincide with the pressure forming main trajectory; phase difference is the start-up lag time of the temperature following sub-trajectory relative to the pressure forming main trajectory; entry and exit conditions are the triggering conditions for allowing the temperature following sub-trajectory to enter or exit the overlap region; valve baseline instruction is a sequence of valve target instructions generated based on the pressure forming main trajectory; water side baseline instruction is a sequence of water injection target instructions generated based on the temperature following sub-trajectory; atomization establishment criterion and gate signal generation is a determination process for determining whether the nozzle atomization is effective within the first wave window and outputting the corresponding gate signal, including joint determination of the pressure difference condition, the slope condition and the water source condition; water side pre-pressurization and communication is a process for establishing a stable pressure in the water side pipeline and forming a continuous flow state, including sequence control and communication confirmation; valve side slope convergence to a set range refers to a state in which the instantaneous slope of the pressure forming main trajectory is lower than a predetermined proportion of the upper limit of the pressure change rate in the envelope threshold or enters the converging segment; water source stability refers to the change rate of water source pressure and water source temperature being lower than the water side change limit corresponding to the envelope threshold and the water path being connected without air blockage; the gate signal of the atomization effective gate is a switch quantity for controlling whether the subsequent limited micro-correction is allowed to enter, including an open state and a closed state; the pressure difference between the nozzle and the steam is continuously maintained above the threshold value and remains for a predetermined time, which means that the difference between the nozzle inlet pressure and the steam injection position pressure is not lower than the nozzle minimum pressure difference in the envelope threshold value and is continuously maintained for the minimum duration specified by the entry and exit conditions; physical constraint diffusion estimation is an estimation method based on the output safety envelope and the envelope threshold, and taking the nozzle minimum pressure difference as the access condition, for time-delayed distribution of the downstream temperature pressure deviation within the first wave window, for determining the distribution form of the micro-correction at each time; limited micro-correction refers to a small correction action applied to the valve baseline instruction and the water side baseline instruction when the gate signal of the atomization effective gate is in the open state, which is limited by the safety envelope and the envelope threshold; Micro-correction increment refers to the change in valve opening or water flow that is allowed to be superimposed on the valve baseline command or water-side baseline command per unit time. The amplitude limit that decreases with the progress of the first wave refers to the limit on the maximum allowable amplitude of the micro-correction increment that decreases monotonically with time within the first wave window, which is used to ensure that the subsequent actions gradually weaken. Downstream temperature and pressure deviation refers to the deviation of downstream inlet temperature and downstream inlet pressure from the target range or baseline guide value. Applying envelope projection to the synthesis results involves mapping the synthesis commands to a set of actions that satisfy the upper temperature limit, upper pressure limit, allowable temperature change rate, allowable pressure change rate, and minimum nozzle pressure difference. The action-side rate position is a concrete manifestation of mapping the controlled variable constraint in the safety envelope to the actuator action constraint. For example, the upper limit of the pressure change rate is obtained from the upper limit of the valve change rate, and then the valve-side rate position is obtained. By limiting the position, it is ensured that the micro-correction increment will not cause the actuator action rate to exceed the limit, thereby avoiding material thermal shock from the source. Automatically weakening and backing back the micro-correction increment when approaching the boundary means that when the synthesized command approaches the safety envelope boundary, the micro-correction increment of the corresponding side is reduced according to the preset back-back ratio, so that the synthesized command remains within the safety envelope; the output synthesized command for execution is to send the valve-side synthesized command and the water-side synthesized command after envelope projection processing to the corresponding actuators for execution.

[0007] Preferably, the step of determining the start and end times of the first wave window includes: taking the start and stop triggering time of the de-cooling and de-pressure system as the start point of the first wave window, and taking the earliest time when the downstream inlet temperature change rate and the downstream inlet pressure change rate simultaneously do not exceed the steady-state threshold and remain there for a predetermined time as the end point of the first wave window.

[0008] Preferably, the construction of the pressure forming main trajectory and the temperature following secondary trajectory includes: A phase difference is set, which is determined to be the instantaneous slope of the pressure forming main trajectory being lower than a predetermined proportion of the allowable pressure change rate or the earliest time of entering the convergence segment. The lag between the start time of the temperature-following secondary trajectory and the start time of the pressure forming primary trajectory is set as the phase difference.

[0009] Preferably, the monitoring nozzle pressure difference and pressure forming main trajectory slope meet the preset conditions including: the pressure difference between the nozzle and the steam is higher than the minimum pressure difference of the nozzle and is maintained for a predetermined time, and the instantaneous slope of the pressure forming main trajectory converges to below a predetermined proportion of the allowable pressure change rate or enters the convergence segment, and the change rate of water source pressure and water source temperature is stable.

[0010] Preferably, the calculation of the micro-correction increment includes: when the gating signal is turned on, generating the original correction amount through sensitivity inverse mapping based on the downstream temperature and pressure deviation, and applying an amplitude limit that decreases with the progress of the first wave to obtain the micro-correction increment.

[0011] Preferably, the implementation of envelope projection includes: calculating a scaling factor for the synthetic command, prioritizing the retraction of the water-side micro-correction increment to meet the nozzle minimum differential pressure and temperature constraints, then retracting the valve-side micro-correction increment to meet the pressure constraints, and the scaling factor is dynamically calculated based on the action-side rate position and the measurement-side margin.

[0012] Preferably, the handover to conventional control includes: when the rate of temperature change and the rate of pressure change are both below the steady-state threshold and remain below the threshold for a predetermined time, freezing the timing script, turning off the gating signal, clearing the micro-correction increment to zero, and retaining the envelope threshold as the initial value for the next first-wave window determination.

[0013] On the other hand, the present invention also provides a decoupling control system for the thermal hysteresis first peak of a de-cooling and de-pressure reducing system, comprising: The first wave window determination and safety envelope setting module determines the start and end time of the first wave window of the de-cooling and de-pressure system, and establishes a safety envelope based on the allowable temperature change rate, pressure change rate, minimum nozzle pressure difference and material thermal shock limit, thereby obtaining the first wave window parameters, envelope threshold and steady state threshold. The trajectory generation module constructs the pressure forming main trajectory and the temperature following secondary trajectory based on the first wave window parameters and the envelope threshold. The pressure forming main trajectory is divided into three segments: starting slope, linear climb and convergence. The overlap area duration and phase difference are set to obtain the valve baseline command and the water-side baseline command. The gating signal generation module monitors the nozzle pressure difference and the slope of the pressure forming main trajectory to ensure that the preset conditions are met, based on the valve baseline command and the water side baseline command, and outputs a gating signal for effective atomization gating. The micro-correction calculation module calculates the micro-correction increment based on the gate signal and the temperature and pressure deviation downstream of the de-cooling and de-pressure reduction system, and limits it within a safe envelope. The command synthesis module synthesizes the micro-correction increment with the valve baseline command and the water-side baseline command, and performs envelope projection on the synthesis result to maintain the peak-shifting structure from being destroyed. It outputs the synthesized command to drive the actual action of the desuperheating and pressure-reducing valve and the injection device. Monitor the rate of change of temperature and pressure downstream of the de-cooling and de-pressure reduction system, and shut down the gate control and hand over to normal control when the steady-state threshold is reached.

[0014] The present invention has the following beneficial effects: 1. Significantly Improved Control Performance: Simulation and field trials show that the temperature overshoot within the initial window is reduced by 50%-80%, and the peak pressure disturbance is reduced by 30%-50%, effectively preventing temperature overshoot and pressure disturbance caused by unevaporated water entering the downstream area. The minimum differential pressure failure event of the nozzle is reduced to 0, and the frequency of envelope overshoot triggering is reduced by more than 90%, ensuring that water jetting only participates when atomization is effective, thus eliminating the risk of thermal shock at the source.

[0015] 2. Enhanced Equipment Protection and Reliability: By explicitly mapping material thermal shock limits to actuation-side rate parameters, excessive wall temperature gradients caused by valve and water-side "overspeed" are avoided. The initial convergence time is shortened by 20%-35%, and the rate of temperature and pressure change during steady-state handover remains within the steady-state threshold, with control switching impact less than 2% of the set step size. When water source fluctuations or nozzle differential pressure approaches the boundary, the priority backoff mechanism automatically weakens water-side micro-correction, resulting in faster differential pressure margin recovery, an 80% reduction in related alarms, and an overall reduction of 60%-70% in alarm and backoff actions.

[0016] 3. Engineering Applicability and Safety: It achieves temporal decoupling of "pressure first, temperature later", meeting the stringent safety objectives of zero unevaporated water introduction and zero nozzle differential pressure violation in start-up, shutdown, and bypass scenarios. Through safety envelope projection and gating collaboration, it solves the core problems of dispersed constraints and overlapping time sequences in existing technologies. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the method flow in Example 1; Figure 2 This is a schematic diagram of step S3 in Example 1; Figure 3 This is a schematic diagram of step S4 in Example 1; Figure 4 This is an integrated schematic diagram of peak shifting, gating, and security envelope. Detailed Implementation

[0018] 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.

[0019] It should be understood that the step numbers used in the text are for ease of description only and are not intended to limit the order in which the steps are performed.

[0020] It should be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0021] The terms “comprising” and “including” indicate the presence of the described feature, whole, step, operation, element and / or component, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or collections thereof.

[0022] The term “and / or” refers to any combination of one or more of the associated listed items, as well as all possible combinations, and includes these combinations.

[0023] Example 1: To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments of the present application and with reference to the accompanying drawings.

[0024] To address the problems of existing technologies, this invention provides a decoupling control method for the first peak of thermal hysteresis in a de-cooling and de-pressure reducing system, comprising the following steps: Step S1: Determine the start and end times of the first wave window of the de-cooling and de-pressure reduction system, and establish a safety envelope based on the allowable temperature change rate, pressure change rate, minimum nozzle pressure difference and material thermal shock limit to obtain the first wave window parameters, envelope threshold and steady state threshold. In this embodiment, the determination of the first wave window and its start and end points are based on the start-stop triggering of the de-cooling and de-pressure reduction system. Let the start-stop triggering time be... ( (The timestamp corresponding to the start / stop trigger); assuming the downstream inlet temperature is... ( For a moment (downstream inlet temperature), downstream inlet pressure is ( For a moment The downstream inlet pressure), and the corresponding rates of temperature change and pressure change are respectively and ( This is the first derivative of temperature with respect to time. (This is the first derivative of pressure with respect to time).

[0025] Let the steady-state threshold be a pair of rate-of-change thresholds. ( This is the steady-state threshold for the rate of temperature change. (steady-state threshold for the rate of pressure change), and a predetermined time. ( (Minimum continuous hold time required to determine the end of the first wave window).

[0026] The end point of the first wave window ( (The end time of the first wave window) is defined as satisfying the condition within the interval There are simultaneously inside and The earliest moment; the duration of the first wave window is ( (Duration of the first wave window).

[0027] The parameters of the first wave window are denoted as ,in Divide the threshold set for the stage ( Used for subsequent segmentation of the main pressure forming trajectory, a set of inequality thresholds is taken, satisfying... , ,and (See envelope threshold below for definition).

[0028] Secondly, the safety envelope and its threshold are defined. The safety envelope is represented as a set of constraints that varies over time. ( For a moment The set of permissible actions and controlled variables is defined by both the envelope threshold and the admission criteria. ,in This is the upper limit of temperature. The upper limit of pressure, For the allowable rate of temperature change, For the allowable rate of pressure change, This represents the minimum pressure difference at the nozzle. To clarify the determination of the minimum pressure difference at the nozzle, the instantaneous pressure difference between the nozzle and the steam is defined as... ( For a moment Water-side nozzle inlet pressure, For a moment (Steam side injection position pressure).

[0029] Writing on the fundamental limitations of the safety envelope on the controlled quantity

[0030] Of the above restrictions, It serves as the entry condition for water jetting and is directly used to control subsequent water-side actions.

[0031] Material thermal shock limits are used to tighten the permissible rate of change. Let the upper limits for the rate of temperature change and the upper limits for the rate of pressure change provided by the material thermal shock limits be respectively... and ( This is the upper limit of the rate of temperature change that the material can withstand. (This represents the upper limit of the pressure change rate that the material can withstand); assuming the initial operating limits given by the working conditions are respectively... and ( This represents the upper limit of the initial temperature change rate under operating conditions. (This is the upper limit of the initial pressure change rate under operating conditions).

[0032] The final allowable rates of temperature change and pressure change are determined as follows:

[0033] The above and Included , which serves as a hard boundary for the safety envelope in relation to temperature and pressure dynamics.

[0034] Furthermore, the minimum pressure difference of the nozzle is determined based on the nozzle structural parameters and operating condition diagram, forming an entry threshold for effective atomization within the first wave window. Let the minimum effective evaporation pressure difference obtained by jointly determining the nozzle structural parameters and operating condition diagram be... ( (Minimum pressure difference required to achieve effective atomization and evaporation) The achievable pressure difference range on site is: ( (This is the maximum nozzle pressure differential that the device can achieve under current operating conditions). Then take... and The lower bound is used as the minimum nozzle pressure difference in the envelope threshold to ensure that water jetting is only allowed if atomization can complete heat absorption within the first wave window timescale.

[0035] The aforementioned restrictions on the controlled variable are equivalently mapped to the action boundary on the execution side, used to constrain the subsequent changes in valve opening and water flow. Let the valve opening increment be... ( (where the valve opening is a superimposed change within a discrete time step), the rate of change of the valve opening is... ( (where the valve opening is the first derivative with respect to time) and the water volume increment is ( (where the water quantity is a superimposed change within a discrete time step), and the rate of change of water quantity is... ( (The first derivative of water volume with respect to time). Without violating... Given the premise, obtain the action set ( For a moment The set of actionable actions on the execution side, in its basic form is

[0036] in and For the reason and The corresponding upper limit obtained through system sensitivity calibration ( This represents the upper limit of the rate of change of valve opening. (Upper limit for the rate of change of water volume). Final safety envelope writing. ( The set of constraints on the controlled variable side includes (and all constraints on its rate of change).

[0037] Finally, three types of results are output to drive subsequent steps: (1) Initial window parameters ,in Used to divide the main trajectory of pressure forming into three segments: starting slope, linear climb and convergence; (2) envelope threshold (3) Steady-state threshold and scheduled time This is used to determine the end of the first wave window.

[0038] Step S2: Based on the first wave window parameters and envelope threshold, construct the pressure forming main trajectory and temperature following secondary trajectory, divide the pressure forming main trajectory into three segments: starting slope, linear climb and convergence, and set the overlap area duration and phase difference to obtain the valve baseline command and water-side baseline command. In this embodiment, the pressure forming main trajectory and temperature following secondary trajectory are constructed using the first wave window parameters and envelope threshold output in step S1 as boundaries. The segmented design of the three segments of starting slope, linear climb and convergence is completed. The maximum increment and maximum slope of each segment are limited, the overlap area duration and phase difference are set, and the entry and exit conditions are defined. Finally, the valve baseline command and water-side baseline command are output as inputs for subsequent steps.

[0039] Define the structure and notation of segmented timing scripts. Let the valve baseline command be... ( For a moment The corresponding PRDS desuperheating and pressure reducing valve opening target), the water-side baseline command is ( For a moment (Corresponding water jet volume or water valve opening target). To directly constrain the pressure forming process in the time domain, a definition is given by... The induced reference pressure trajectory is ( For a moment (reference downstream inlet pressure), its instantaneous slope is ( (referring to the first derivative of the reference pressure trajectory with respect to time), and... limited The maximum segment size. The starting gentle slope is set to... ,satisfy The linear climb segment is set to... ,satisfy The convergence segment is set to ,satisfy since Towards Monotonically decreasing, and .in, , , These are the durations of the initial gentle slope, the linear climb, and the finish line, respectively. , , It is a non-negative constant used for allocation. To align with the action boundary, the upper limit of the valve opening change rate is denoted as... ( Depend on (obtained through system sensitivity calibration), and based on this, the maximum increment of each segment is constrained: the... The maximum increment of valve opening per segment is ( For the first The upper limit of the total allowable change in valve opening within the segment. ).

[0040] Secondly, the relationship between the temperature-following secondary trajectory and the temporal peak shifting is constructed. Temperature-following secondary trajectory By comparing the phase difference and the duration of the overlap region on the time axis Peak shifting. Let the phase difference be... ( (This refers to the start-up lag time of the temperature-following secondary trajectory relative to the pressure forming primary trajectory), and the overlap period is... ( for and (The allowed duration of overlap in time). Entry and exit conditions use a unified expression: entry conditions require... The slope condition of the main pressure forming trajectory and the minimum nozzle pressure difference must be satisfied simultaneously at all times. The slope condition is: Or enter the convergence phase ( For the predetermined ratio, (For the allowable rate of pressure change), the minimum differential pressure of the nozzle is indicated by the threshold from step S1. (Specific gate control is determined by step S3); Exit condition is: Or exit early if the water-side actions in the subsequent section would disrupt the peak-shifting structure within the first wave window.

[0041] In the aforementioned time structure, setting the phase difference is crucial for achieving pressure-first shaping followed by temperature. The planned phase difference is obtained using the slope-convergence optimization calculation criterion. Defined as follows: Within the first wave window, when the instantaneous slope of the reference pressure trajectory is lower than a predetermined proportion of the upper limit of the pressure change rate in the envelope threshold, or when the main trajectory enters the convergence segment, the earliest start lag of the temperature-following sub-trajectory is determined by the earliest time that both conditions are met.

[0042] in, To minimize the phase difference required to meet peak shifting requirements; From Delayed variables for initial calculation; The duration of the first wave window; The instantaneous slope of the reference pressure trajectory; For a predetermined ratio, the range of values ​​is [not specified]. ; The allowable rate of pressure change; and These represent the durations of the initial gentle slope and the linear climb, respectively. Based on this formula, the planned phase difference is... This ensures that the temperature-following secondary trajectory only starts after the main trajectory enters the low-slope region or the convergence segment, thus avoiding the high-slope phase on the valve side from the time axis.

[0043] The amplitude and timing of the temperature-following sub-trajectory are synchronized by combining the envelope threshold. The upper limit of the water-side rate of change is denoted as... ( Depend on (obtained through system sensitivity calibration), based on which the maximum increment of each segment on the water side is limited to... ( For the first The upper limit of the total allowable water-side variation within the section The actual duration of water-side participation in each segment is subject to the following: And it does not overlap with the steep slope phase of the starting gentle slope). The water-side start-up time is taken as... ,exist Internal output At the same time, maintain The changes are subject to and and maintain with time The phase difference and overlap period duration are determined to ensure that the staggered structure is not destroyed.

[0044] Clearly define the binding relationship between the maximum slope and the maximum increment of each segment, and the strategy for connecting entry and exit conditions. For the main trajectory of pressure forming, the maximum slope of the initial gentle slope segment should not exceed... The maximum slope of the linear climb segment is taken as The maximum slope of the convergence segment is from Towards Monotonically decreasing, and satisfying the condition throughout. For the temperature-following secondary trajectory, the rate of change on the water side must not exceed a certain limit throughout the entire process. and remain in place if the entry condition is not met. Do not start or perform only zero action; when the exit condition is met or reached. hour, Stop outputting increments and maintain existing values. The above entry and exit conditions are connected to the effective gating of atomization in step S3: this step only defines conditions in a temporal sense (i.e., slope and piecewise conditions), and whether water jetting is allowed is determined by step S3 based on... The gating signal determines this.

[0045] Output valve baseline command and water-side baseline command. Valve baseline command exist The internal design follows a segmented approach, with a gentle initial slope, linear ascent, and convergence, satisfying the constraints of maximum slope and maximum increment for each segment, while ensuring the reference pressure trajectory. The entire process falls within the safety envelope Waterside baseline directive exist Internal output satisfies the constraints of maximum increment and rate of change for each segment on the water side, and maintains consistency with... The predetermined phase difference and overlap period duration. Together, they constitute a segmented timing script, providing a baseline for subsequent steps that can be superimposed with limited micro-corrections without altering the peak-shifting structure.

[0046] Step S3: Based on the valve baseline command and the water side baseline command, monitor the nozzle pressure difference and the slope of the pressure forming main trajectory to ensure that they meet the preset conditions, and output the gate control signal for effective atomization gate control; In this embodiment, as shown in the appendix Figure 2 As shown, the valve baseline command and water-side baseline command output in step S2 are used as time references, and the envelope threshold and first wave window parameters output in step S1 are used as boundaries to advance water-side pre-pressurization and connection. The differential pressure condition, slope condition and water source condition are jointly determined, and the opening or closing status of the atomization effective gating gate signal is output in the time domain that meets the entry and exit conditions.

[0047] Clearly define the symbols used for time and trajectory references. The start and end points of the first wave window are respectively... and ( The start / stop trigger time, (This refers to the end time of the first wave window), and the duration of the first wave window is... ( (This refers to the duration of the first wave window). The phase difference between the temperature-following secondary trajectory and the pressure-forming primary trajectory is... ( (For start-up lag time), the allowed overlap period is... ( (The duration during which the two trajectories are allowed to overlap). The reference pressure trajectory for the master pressure forming trajectory is... ( For a moment (reference downstream inlet pressure), its instantaneous slope is ( (Referring to the first derivative of the reference pressure trajectory with respect to time). The segment duration for segmented allocation is... , , ( The duration of the initial gentle slope section. The duration of the linear climb phase. For the duration of the convergence segment, satisfying The envelope threshold is denoted as... ( This is the upper limit of temperature. The upper limit of pressure, For the allowable rate of temperature change, For the allowable rate of pressure change, (Minimum pressure difference at the nozzle). The instantaneous pressure difference between the nozzle and the steam is... ( For a moment Water-side nozzle inlet pressure, For a moment (Steam-side injection location pressure). The proportionality coefficient for slope convergence is... ( For relative to A predetermined ratio is used to determine whether the valve slope falls within a set range. The minimum continuous holding time used to determine whether the valve can be continuously maintained above a threshold for a predetermined period is... ( The minimum continuous time window for establishing criteria for atomization. Water source pressure and water source temperature are respectively... and ( For a moment Water source side pressure, For a moment (Water source side temperature), and their rates of change are respectively and ( The first derivative of water pressure with respect to time. (This is the first derivative of the water source temperature with respect to time). The mapping coefficient for water source stability is... and ( For the relative rate of change of water source pressure The tightening coefficient, For the relative rate of change of water source temperature (Tightening coefficient). Water-side preloading and connectivity confirmation are determined using a combination of ratio threshold and time window: take ( (The threshold value of the connection ratio between the nozzle inlet pressure and the water source pressure) and ( Define the connectivity confirmation flag (minimum duration for connectivity confirmation). ( For a moment The connection confirmation switch quantity is activated when the connection condition is met. Otherwise The gating signal for effective atomization gating is denoted as... ( For a moment The switching quantity of effective gating for atomization. It is in the on state. (In the off state). For ease of logical expression, use... Logical AND ( For the logical AND operator, use Represents logical OR ( For the logical "OR" operator, use Quantifiers indicating the whole ( This means "it holds true at any time within the time window".

[0048] Promote water-side pre-pressurization and connection, and set up joint judgments based on pressure difference, slope, and water source. Water-side pre-pressurization and connection are controlled according to the opening sequence to establish stable water pressure, and a connection confirmation flag is used to determine whether a continuous flow state has been formed: when within the time window... Internal satisfaction For any At the time of establishment, ,otherwise .

[0049] Differential pressure conditions are determined continuously using a sliding time window: when within the time window Internal satisfaction For any When the condition is met, it is recorded as the pressure difference condition being met.

[0050] The slope condition adopts the slope-convergence selection principle: within the time window If for any All meet Or, the current moment has entered the convergence phase (i.e., If the slope condition is true, then it is considered true. The water source condition is determined by the tightening of the rate of change: within the time window... If for any All meet and If the condition is met, it is considered that the water source condition is established. To adhere to the staggered peak structure of the segmented time-series script, the gate signal is determined only when... It will be carried out internally.

[0051] Based on the above joint determination, the gating signal for effective atomization gating. The generation adopts the following unified formula, which centrally reflects the parallel determination of pressure difference conditions, slope conditions, water source conditions, and connectivity confirmation under the constraints of the first wave window and phase difference:

[0052] in, The gate signal is for effective atomization gating; This is the current determination time; The start / stop trigger time; This is the closing time of the first window; The phase difference of the temperature-following sub-trajectory; Allowed overlap duration; Establish a minimum continuous time window for the criteria of atomization; This refers to the instantaneous pressure difference between the nozzle and the steam. The minimum nozzle pressure difference in the envelope threshold; The instantaneous slope of the reference pressure trajectory; For relative to The slope tightening ratio; The allowable rate of pressure change; , The duration of the initial gentle slope and the linear climb section; and These represent the rates of change of water source pressure and water source temperature, respectively. and The tightening factor is the rate of change of the water source. Connectivity confirmation flag; symbol This means "true at any time within the time window", symbol The symbol represents the logical "AND". The expression represents the logical "OR". This formula takes the continuous satisfaction within the time window as the criterion, ensuring that the pressure difference, slope and water source conditions are met simultaneously, and that the water channel has completed pre-pressurization and connectivity confirmation. Moreover, the determination is only made within the time interval defined by the phase difference and the duration of the overlapping area, thus maintaining a staggered relationship consistent with the segmented timing script.

[0053] Finally, the output and maintenance rules of the gating signal are as follows: When When the gate signal is in the open state, it allows restricted micro-correction to enter in subsequent steps; when any condition is no longer met or exceeds the limit... The time domain Set immediately The gating signal is in the closed state. The above gating signal is only effective within the first wave window and serves as the only access switch in step S4. It ensures that water-side action is allowed only when the pressure difference between the nozzle and the steam is continuously maintained above the threshold for a predetermined time, the valve slope converges to the set range, and the water source is stable and the connection is confirmed. This allows for stable peak-shifting coordination with the pressure forming main trajectory and the temperature following secondary trajectory on the time axis.

[0054] Step S4: Calculate the micro-correction increment based on the gate signal and the temperature and pressure deviation downstream of the de-cooling and de-pressure reducing system, and limit it within the safety envelope; In this embodiment, as shown in the appendix Figure 3 As shown, step S4 (the restricted micro-correction of physical constraint diffusion estimation) uses the gating signal of the effective atomization gating output in step S3 as the sole admission switch, takes the valve baseline command and water-side baseline command output in step S2 as references, and is constrained by the envelope threshold and safety envelope output in step S1. The micro-correction increment is calculated only when the effective atomization gating is opened, and the amplitude limit decreases with the progress of the first wave to ensure that the micro-correction increment falls within the action-side limit of the safety envelope. The micro-correction increment is output for subsequent use.

[0055] Define the deviation, reference trajectory, and sensitivity mapping for this step. The downstream inlet pressure and downstream inlet temperature are respectively... and ( For a moment Downstream inlet pressure, For a moment (Downstream inlet temperature). Determined by valve baseline command. The induced reference pressure trajectory is ( For a moment (Reference downstream inlet pressure); by waterside baseline command The induced reference temperature trajectory is ( For a moment (Referencing downstream inlet temperature). The downstream temperature-pressure deviation is defined as... and ( The deviation of pressure from a reference, (This refers to the temperature deviation relative to the reference). Considering the linearization sensitivity of the valve side and water side to the controlled variable, a time-varying sensitivity matrix is ​​defined.

[0056] in The instantaneous gain of valve opening on downstream inlet pressure, For the instantaneous gain of water-side action on downstream inlet pressure, The instantaneous gain of valve opening on downstream inlet temperature. This represents the instantaneous gain of the water-side action on the downstream inlet temperature. To represent peak distribution, the instantaneous slope of the pressure forming master trajectory is continued. ( (referring to the first derivative of the reference pressure trajectory with respect to time), and the slope tightening ratio. ( For relative to The ratio is used to determine whether the valve slope falls within the set range. The start and end points of the first wave window are... and The duration is ( The start / stop trigger time, The closing time of the first window. (Duration of the first wave window).

[0057] Secondly, the amplitude limit and the safety envelope position constraint on the action side are given, which decrease with the progress of the first wave. Let the control time step be... ( (The time interval between adjacent control commands), the upper limit of the valve opening change rate and the upper limit of the water flow change rate are respectively... and ( Depend on The sensitivity was obtained through system calibration. Depend on (Obtained through system sensitivity calibration). To ensure that the total rate of change does not exceed the allowable upper limit, the instantaneous rate of change of the baseline command is defined as... and ( and (These are the instantaneous rates of change of the valve baseline command and the water-side baseline command, respectively). Therefore, the available position for the micro-correction increment on the actuation side is...

[0058]

[0059] in This represents the maximum micro-correction amplitude that can be superimposed on the valve side at the current time step. This represents the maximum micro-correction amplitude that can be superimposed on the water side at the current time step.

[0060] The decrease factor of the first wave process is defined as

[0061] in The amplitude weight, which decreases monotonically over time, is used to distribute the micro-correction increment over time along the remaining duration of the first wave window.

[0062] To reflect the staggered peak constraint of pressure forming first and temperature following later, a staggered peak allocation factor matrix is ​​defined.

[0063] in Waterside participation (when) When larger Approaching ,when When convergence enters the set range (increase) This refers to the valve-side participation rate.

[0064] Based on the above definitions, the core of this step is the constrained micro-correction calculation of diffusion estimation that simultaneously satisfies the physical constraints of gating, peak shaving, and safety envelope action-side limitations. This is only true if the gating signal of effective atomization gating is met. When, calculate the micro-correction increment; when At this point, the micro-correction increment is zero. To achieve approximately decoupled correction of pressure and temperature deviations, inverse sensitivity mapping is used to generate the original correction value, and constrained micro-correction is obtained through amplitude reduction and action-side projection.

[0065]

[0066]

[0067]

[0068]

[0069] in, For a moment The micro-correction increment superimposed on the valve baseline command, For a moment Micro-correction increments superimposed on the waterside baseline command; The gate signal is for effective atomization gating; The magnitude is limited to decrease as the first wave progresses; Assign a factor matrix to stagger peaks; The inverse of the sensitivity matrix (when (existing at the time) and These are pressure deviation and temperature deviation, respectively. For action-side rate positions The component projection operator; It is an interval projection function that ensures that each component falls within a given closed interval.

[0070] Achieving sensitivity inverse mapping and Approximate decoupling correction, to Micro-correction is preferentially allocated to the valve side or the water side to maintain the peak-shifting structure. The available correction will gradually decrease as it spreads along the remaining first wave, and... Ensure that the micro-correction increment does not exceed the rate limit of the safety envelope on the action side.

[0071] Furthermore, the connection between this step and the envelope threshold and effective atomization gating is as follows: Envelope Threshold The permissible rates of temperature and pressure change are defined, and the minimum differential pressure at the nozzle is given. and Mapped to the action-side constraints, the specific threshold for the minimum differential pressure of the nozzle is obtained from step S3. Guarantee, therefore The micro-correction increment can only be calculated when... or Direct order and Meanwhile, the staggered allocation factor and Depend on relatively The degree of convergence determines whether the valve side is mainly responsible for micro-correction when the main pressure forming trajectory is in a high slope stage. After the valve side slope converges to the set range, the water side is allowed to gradually take on a higher proportion of micro-correction, thus maintaining a consistent peak-shifting relationship with the temperature-following secondary trajectory on the time axis.

[0072] Finally, the output and usage of the micro-correction increment are as follows: at each control step According to the above formula, we get and And superimpose them onto the valve baseline command respectively. With waterside baseline instructions Pre-synthesized instructions are generated for use in the next step; when the gating signal is closed or the first wave window ends. and Set to zero and hold.

[0073] Step S5: Combine the micro-correction increment with the valve baseline command and the water-side baseline command, and perform envelope projection on the combined result to maintain the staggered peak structure from being destroyed. Output the combined command to drive the actual operation of the desuperheating and pressure reducing valve and the injection device. In this embodiment, while keeping the phase difference and overlap region duration and entry and exit conditions formed in step S2 unchanged, only the micro-correction increment output in step S4 is scaled and envelope projected, so that the synthesis command simultaneously satisfies the envelope threshold and the minimum nozzle pressure difference given in step S1, and automatically weakens and backs up the micro-correction increment when approaching the boundary, thereby maintaining the staggered structure of the segmented timing script without being destroyed.

[0074] Here's an explanation of the characters involved in this step: The valve baseline command is denoted as... (time The corresponding PRDS valve opening target), the water-side baseline command is denoted as (time (Corresponding water jet volume or water valve opening target); micro-correction increments are respectively and (time The micro-correction component superimposed on the baseline command originates from step S4, and in (Except for zero); sensitivity gain is , , , (These represent the effects of valve-side and water-side actions on the downstream inlet pressure, respectively.) With downstream inlet temperature (instantaneous gain); envelope threshold is (Upper temperature limit) Pressure limit Permissible rate of temperature change Permissible rate of pressure change Minimum pressure difference of nozzle The remaining upper limit and remaining rate margin on the measurement side are denoted as follows: , , , (in and (The first derivatives of pressure and temperature with respect to time); the control time step is... (Time interval between adjacent control commands); Action-side rate positions are respectively and (The maximum micro-correction amplitude that can be superimposed at the current time step is derived from step S4); the instantaneous pressure difference between the nozzle and the steam is The pressure margin is (Remaining amount from the minimum pressure difference of the nozzle); Pressure difference - water-side action conversion factor is (Convert the differential pressure margin to a coefficient for the allowable superposition amplitude on the water side). To reflect the effective water-side position after nozzle constraint, take... .symbol This indicates non-negative truncation.

[0075] Envelope projection and priority backoff are implemented using a single scaling-composition formula. The water-side component is first scaled to meet nozzle and temperature constraints, and then the valve-side component is scaled to meet pressure constraints. The final output is the composite command.

[0076] in:

[0077]

[0078] in, and These are the valve-side and water-side synthesized commands after envelope projection and back-off processing, respectively; The water-side scaling factor is the minimum value determined by the combined constraints of nozzle limitations and the upper limits and rates of change of temperature and pressure. The scaling factor is used on the valve side, and the pressure constraint is coupled back off after considering the water-side scaling. The absolute value in the denominator is used to unify the gain sign and avoid constraint misjudgment caused by directionality. When any denominator is zero or the joint constraint cannot be satisfied, the corresponding scaling factor is taken as... This indicates a complete rollback of the micro-correction increment for that component.

[0079] The execution logic of the above formula is as follows: at each control step First, calculate based on the nozzle constraint and the combined upper limit of temperature and pressure on the measurement side, as well as the rate margin. Weakening water-side micro-correction to ensure And without breaking through and Then, based on the upper pressure limit and the allowable rate of pressure change, and considering the scaled coupling contribution on the water side, calculate... Prioritize the reversal of valve-side micro-calibration to ensure and Finally, the scaled microcorrection is added to the baseline command to obtain the result. and Used for execution. Because scaling only applies to the micro-correction increment and does not change... and The time structure, and the microcorrection in Outside of zero, the staggered structure of the segmented timing script naturally remains unchanged. When any constraint approaches the boundary, it causes... or This means that when approaching the boundary, the micro-correction increment is automatically weakened and rolled back, ensuring that the synthesized instructions always fall within the safe envelope.

[0080] Step S6: Monitor the rate of change of temperature and pressure downstream of the de-cooling and de-pressure reducing system, and close the gate control and transfer it to normal control when the steady-state threshold is reached.

[0081] In this embodiment, the first wave window parameters and envelope threshold output in step S1 are used as boundaries, and the synthesized command after envelope projection processing output in step S5 is used as the execution object. When the first wave window end condition is met, the atomization effective gating is closed, the micro-correction increment is cleared, and the baseline command is taken over in steady state, and the stability of the controlled quantity is maintained within the constraints.

[0082] Specifically, the execution phase will and (The combined valve-side and water-side commands, processed by envelope projection, are respectively) sent to the corresponding actuators for continuous monitoring. , and and with , , , and Perform constraint checks. The window end check uses the constraints defined in step S1. With steady-state threshold and :when Or within a time window Simultaneously satisfy and For any Upon establishment, the first wave window is considered to have ended. At this time, the gating signal for effective atomization gating is set. And make the micro-correction increment and This makes the synthesized instruction equal to the baseline instruction, i.e. , Phase difference Duration of overlapping areas No longer constraining instructions.

[0083] During the steady-state takeover phase, a unified boundary is maintained for both the action and measurement sides: if detected... , If its rate of change approaches the upper limit, then the approach of step S5, which involves automatically weakening and reverting the micro-correction increment when approaching the boundary, is followed. However, since the micro-correction has been cleared to zero, this only applies to... and The rate of change of is conservatively limited, so that , and maintain If a new start / stop trigger occurs, the process re-enters step S1 to determine the new trigger. and And rebuild the first window.

[0084] As attached Figure 4 As shown, the first wave of decoupling of the PRDS valve-nozzle system is illustrated: on the steam main pipe, the three arrows along the pipe after the valve represent the main trajectory of pressure shaping (gradual slope → linear → convergence); the water-side riser enters the main line through the nozzle after the phase difference, and follows the pressure within the overlapping area. The atomization gating at the nozzle only opens when the pressure difference is ≥ the minimum threshold. The downstream semi-transparent safety envelope reflects the temperature / pressure rate and thermal shock constraints, automatically retreating from the boundary. The gray micro-correction arrows decrease over time and are only superimposed when the gating is open. This invention uses a staggered peak structure of pressure shaping first and temperature following, combined with pressure difference gating and envelope projection, to prevent unevaporated water from entering the downstream, suppress temperature overshoot and pressure disturbance, and ensure material thermal safety; the micro-correction flexibly corrects within the confined space and smoothly transfers to conventional control, significantly improving the controllability and robustness of the first wave stage.

[0085] Example 2: This embodiment provides a decoupling control system for the first peak of thermal hysteresis in a de-cooling and de-pressure reduction system, including: The first wave window determination and safety envelope setting module determines the start and end time of the first wave window of the de-cooling and de-pressure system, and establishes a safety envelope based on the allowable temperature change rate, pressure change rate, minimum nozzle pressure difference and material thermal shock limit, thereby obtaining the first wave window parameters, envelope threshold and steady state threshold. The trajectory generation module constructs the pressure forming main trajectory and the temperature following secondary trajectory based on the first wave window parameters and the envelope threshold. The pressure forming main trajectory is divided into three segments: starting slope, linear climb and convergence. The overlap area duration and phase difference are set to obtain the valve baseline command and the water-side baseline command. The gating signal generation module monitors the nozzle pressure difference and the slope of the pressure forming main trajectory to ensure that the preset conditions are met, based on the valve baseline command and the water side baseline command, and outputs a gating signal for effective atomization gating. The micro-correction calculation module calculates the micro-correction increment based on the gate signal and the temperature and pressure deviation downstream of the de-cooling and de-pressure reduction system, and limits it within a safe envelope. The command synthesis module synthesizes the micro-correction increment with the valve baseline command and the water-side baseline command, and performs envelope projection on the synthesis result to maintain the peak-shifting structure from being destroyed. It outputs the synthesized command to drive the actual action of the desuperheating and pressure-reducing valve and the injection device. Monitor the rate of change of temperature and pressure downstream of the de-cooling and de-pressure reduction system, and shut down the gate control and hand over to normal control when the steady-state threshold is reached.

[0086] Example 3: This embodiment proposes an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the thermal hysteresis first peak decoupling control method for a de-cooling and depressurization system as described in any embodiment of the present invention.

[0087] Example 4: This embodiment proposes a computer-readable storage medium storing a computer program that, when executed by a processor, implements the thermal hysteresis first peak decoupling control method for a de-cooling and de-pressure reducing system as described in any embodiment of the present invention.

[0088] In this application embodiment, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent the existence of A alone, A and B simultaneously, or B alone. A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of singular or plural items. For example, at least one of a, b, and c can represent: a, b, c, a and b, a and c, b and c, or a and b and c, where a, b, and c can be single or multiple.

[0089] Those skilled in the art will recognize that the units and algorithm steps described in the embodiments disclosed herein can be implemented using electronic hardware, computer software, or a combination of electronic hardware and software. 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 implementation should not be considered beyond the scope of this application.

[0090] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0091] In the several embodiments provided in this application, any function, if implemented as a software functional unit and sold or used as an independent product, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0092] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for decoupling control of thermal hysteresis first peak of a desuperheating and pressure reducing system, characterized in that, The method comprises the following steps: determining the start and end time of the first wave window of the desuperheating and depressurizing system, and establishing a safety envelope according to the allowed temperature change rate, pressure change rate, nozzle minimum pressure difference and material thermal shock limit to obtain the first wave window parameters, envelope threshold and steady state threshold; According to the first wave window parameters and the envelope threshold, the pressure forming main track and the temperature following sub-track are constructed, the pressure forming main track is divided into three sections of starting ramp, linear climbing and converging, and the overlapping area time and phase difference are set to obtain the valve baseline instruction and the water side baseline instruction; According to the valve baseline instruction and the water side baseline instruction, the nozzle pressure difference and the pressure forming main track slope meet the preset condition, and the gate signal of the atomization effective gate is outputted; According to the gate signal and the temperature and pressure deviation of the desuperheating and depressurizing system downstream, the micro correction increment is calculated and limited in the safety envelope; The micro correction increment is synthesized with the valve baseline instruction and the water side baseline instruction, and the synthesis result is subjected to envelope projection to maintain the staggered peak structure not to be destroyed, and the synthesis instruction is outputted to drive the actual action of the desuperheating and depressurizing valve and the injection device; The temperature and pressure change rate of the desuperheating and depressurizing system downstream is monitored, and the gate is closed and handed over to the regular control when the steady state threshold is reached.

2. The control method of claim 1, wherein: The step of determining the start and end time of the first wave window comprises: taking the start time of the desuperheating and depressurizing system as the start point of the first wave window, and taking the earliest time when the downstream inlet temperature change rate and the downstream inlet pressure change rate are simultaneously not more than the steady state threshold and keep for a predetermined time as the end point of the first wave window.

3. The control method of claim 1, wherein: The step of constructing the pressure forming main track and the temperature following sub-track comprises: The phase difference is set, which is determined as the instantaneous slope of the pressure forming main track being lower than the predetermined proportion of the allowed pressure change rate or entering the converging section; The lag amount of the starting time of the temperature following sub-track relative to the starting time of the pressure forming main track is set as the phase difference.

4. The control method of claim 1, wherein: The step of monitoring the nozzle pressure difference and the pressure forming main track slope meeting the preset condition comprises: the pressure difference between the nozzle and the steam is higher than the nozzle minimum pressure difference and keeps for a predetermined time, and the instantaneous slope of the pressure forming main track converges to below the predetermined proportion of the allowed pressure change rate or enters the converging section, and the change rate of the water source pressure and the water source temperature is stable.

5. The control method of claim 1, wherein: The step of calculating the micro correction increment comprises: when the gate signal is opened, the original correction amount is generated by sensitivity inverse mapping according to the downstream temperature and pressure deviation, and the amplitude limit decreasing with the first wave process is applied to obtain the micro correction increment.

6. The control method of claim 1, wherein: The step of implementing envelope projection comprises: calculating the scaling factor of the synthesis instruction, preferentially retreating the water side micro correction increment to meet the nozzle minimum pressure difference and temperature constraint, then retreating the valve side micro correction increment to meet the pressure constraint, and the scaling factor is dynamically calculated based on the action side rate headroom and the measured side margin.

7. The control method of claim 1, wherein: The step of handing over to the regular control comprises: when the temperature change rate and the pressure change rate are simultaneously lower than the steady state threshold and keep for a predetermined time, freezing the time sequence script, closing the gate signal, clearing the micro correction increment, and keeping the envelope threshold as the initial value for the next first wave window determination.

8. A thermal hysteresis first peak decoupling control system for a desuperheating and pressure reducing system, characterized in that, The method comprises: A first-wave window determination and safety envelope setting module determines the start and end time of the first-wave window of the desuperheating and pressure reducing system, and establishes a safety envelope according to the allowed temperature change rate, pressure change rate, nozzle minimum pressure difference and material thermal shock limit to obtain the first-wave window parameters, envelope threshold and steady-state threshold; A trajectory generation module constructs a pressure forming main trajectory and a temperature following sub-trajectory according to the first-wave window parameters and the envelope threshold, divides the pressure forming main trajectory into three sections of starting ramp, linear climb and convergence, sets the overlap zone length and phase difference, and obtains the valve baseline instruction and water side baseline instruction; A gate signal generation module monitors the nozzle pressure difference and the pressure forming main trajectory slope according to the valve baseline instruction and the water side baseline instruction, and outputs a gate signal of the atomization effective gate according to the preset conditions; A micro-correction amount calculation module calculates a micro-correction increment according to the gate signal and the temperature and pressure deviation downstream of the desuperheating and pressure reducing system, and limits the micro-correction increment within the safety envelope; An instruction synthesis module synthesizes the micro-correction increment with the valve baseline instruction and the water side baseline instruction, and performs envelope projection on the synthesis result to maintain the staggered peak structure from being destroyed, and outputs a synthesis instruction to drive the actual action of the desuperheating and pressure reducing valve and the injection device; The temperature and pressure change rate downstream of the desuperheating and pressure reducing system is monitored, and the gate is closed when the steady-state threshold is reached and handed over to the regular control.

9. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor executes the program to realize the desuperheating and pressure reducing system thermal hysteresis first peak decoupling control method of claims 1-7.

10. A computer-readable storage medium having stored thereon a computer program, characterized in that, The program is executed by the processor to realize the desuperheating and pressure reducing system thermal hysteresis first peak decoupling control method of any one of claims 1 to 7.

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