A dynamic coupling compensatory coordinated control system for thermal power generating units

Abstract

The application discloses a kind of dynamic coupling compensation nature coordinated control system of thermal power generating unit, belong to thermal power generating unit technical field, the system, including dynamic coupling compensation module, adaptive sliding pressure optimization module and coordinated control execution module;Dynamic coupling compensation module receives the load instruction sent by preset control terminal, generates dynamic compensation signal;Adaptive sliding pressure optimization module is based on the time-varying characteristic of thermal power generating unit actual operating parameter, real-time correction preset initial sliding pressure curve, and superimposes the load demand of thermal power generating unit current and the change of boiler heat storage capacity in initial sliding pressure curve, dynamically generates optimal operation initial pressure target value;Coordinated control execution module is used to integrate dynamic compensation signal and optimal operation initial pressure target value into unified control instruction.The application is set by dynamic coupling compensation module, adaptive sliding pressure optimization module and coordinated control execution module, significantly reduce the demand of artificial intervention.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of thermal power generating units, in particular to a dynamic coupling compensation coordination control system of a thermal power generating unit. BACKGROUND

[0002] The existing coordination control system (CCS) of a thermal power generating unit maintains the main steam pressure stable and tracks the load by receiving a load instruction and respectively controlling the boiler side (fuel, air volume) and the steam turbine side (governor opening) to maintain the main steam pressure stable and track the load.

[0003] At present, the steam turbine of a thermal power plant is generally provided with an initial pressure setting curve of the steam turbine provided by the steam turbine manufacturer, however, the curve is obtained under the design condition and cannot describe the dynamic characteristics when the system is running under variable conditions, and the curve is only related to the load and does not consider the influence of other factors on the initial pressure.

[0004] The existing technology has the following problems: 1. Under the low load (30% to 50% of the rated load) deep peak shaving condition, the dynamic coupling between the boiler and the steam turbine is strong, the traditional PID regulation hysteresis is significant, which leads to large fluctuation of the main steam pressure and slow response of the load, and serious dependence on manual intervention; 2. The initial sliding pressure curve provided by the manufacturer cannot adapt to the change of the actual operating condition, which causes the unit to fluctuate when responding to the load instruction.

[0005] Therefore, it is urgent to provide a dynamic coupling compensation coordination control system of a thermal power generating unit to solve the above problems. SUMMARY

[0006] The technical problem to be solved by the present application is to overcome the defects of the above-mentioned prior art and provide a dynamic coupling compensation coordination control system of a thermal power generating unit.

[0007] To solve the above technical problems, one technical scheme adopted by the present application is to provide a dynamic coupling compensation coordination control system of a thermal power generating unit, comprising: a dynamic coupling compensation module, an adaptive sliding pressure optimization module and a coordination control execution module.

[0008] The dynamic coupling compensation module receives a load instruction issued by a preset control terminal, and according to the load instruction, real-time collects the main steam flow of the boiler side, the governor opening of the steam turbine side and the load data key parameter set of the thermal power generating unit through a preset acquisition unit, and automatically generates a dynamic compensation signal according to the load data key parameter set.

[0009] The adaptive sliding pressure optimization module corrects the preset initial sliding pressure curve in real time based on the time-varying characteristics of the actual operating parameters of the thermal power generating unit, and superimposes the current load demand of the thermal power generating unit and the change of the boiler heat storage capacity in the initial sliding pressure curve to dynamically generate an optimal initial pressure target value.

[0010] The coordination control execution module is used for integrating the dynamic compensation signal and the optimal initial pressure target value into a unified control instruction, and a pressure change rate constraint unit is arranged, when the pressure fluctuation of the pipeline where the main steam flow on the boiler side of the thermal power generating unit exceeds a preset threshold, a preset compensation reinforcement mechanism is activated: a pressure compensation instruction is generated based on the amplitude and change direction of the pressure fluctuation of the pipeline where the main steam flow on the boiler side of the thermal power generating unit; the pressure compensation instruction is superimposed on the unified control instruction to form a compensated instruction, and the compensated instruction is synchronized to a preset terminal to control the main steam flow on the boiler side and the valve opening degree on the turbine side of the thermal power generating unit, and track the load data key parameter set of the thermal power generating unit.

[0011] The application further provides that the collection of the load data key parameter set in the dynamic coupling compensation module comprises the following steps:

[0012] S1, the collection unit synchronously collects the main steam flow on the boiler side, the valve opening degree on the turbine side and the load value in the load data key parameter set of the thermal power generating unit when the load instruction is issued;

[0013] S2, when the change rate of the load value exceeds a set threshold, the collection unit collects the fluctuation extreme value of the main steam flow on the boiler side and the action time difference of the turbine valve every second, if the change rate of the load value is within the threshold range, the collection unit continuously collects the peak-valley interval time length and the stable recovery time consumption of the main steam flow on the boiler side;

[0014] S3, the data collected by the collection unit is dynamically weighted and fused according to the change direction of the load value: in the load value rising stage, the fluctuation extreme value of the main steam flow on the boiler side and the action time difference of the turbine valve opening degree are given a high weight, and a load rising delay parameter representing the boiler response lag characteristic quantity is generated; in the load value falling stage, the peak-valley interval time length of the main steam flow is given a high weight, and a load falling inertia parameter representing the pressure decay characteristic quantity is generated; at the same time, the stable recovery time consumption is combined to construct a dynamic stability correction factor, and finally the load data key parameter set is output.

[0015] The application further provides that the specific steps of outputting the load data key parameter set in the step S3 are as follows:

[0016] S31, linear mapping relationship between the fluctuation extreme value of the main steam flow on the boiler side in the thermal power generating unit and the interval length between the peak and the valley is established when the load instruction is in the regular load stage, and a regular characteristic parameter is output; the correlation intensity between the load rise delay parameter and the stable recovery time consumption is strengthened while the action time difference of the turbine governing valve opening degree on the boiler side in the thermal power generating unit is correlated with the load drop inertia parameter when the load instruction is in the deep peak regulation stage, and a deep peak regulation characteristic parameter is output;

[0017] S32, the fluctuation propagation rate of the main steam flow on the boiler side in the thermal power generating unit is extracted for the regular characteristic parameter, and is marked as a regular stability factor; the load rise delay parameter and the load drop inertia parameter are coupled for the deep peak regulation characteristic parameter, and a peak regulation coupling influence factor is generated;

[0018] S33, the regular stability factor and the peak regulation coupling influence factor are uniformly integrated, a working condition type label of the current load instruction is combined, a dynamic stability correction factor with a working condition identification is generated, and finally a load data key parameter set containing the load rise delay parameter, the load drop inertia parameter and the dynamic stability correction factor is output.

[0019] The application further provides that: the time-varying characteristics of the actual operation parameters of the thermal power generating unit in the self-adaptive sliding pressure optimization module include the main steam temperature, the feed water flow and the environment temperature.

[0020] The application further provides that: the generation steps of the dynamic compensation signal in the dynamic coupling compensation module are as follows:

[0021] Q1, the load data key parameter set is time stamped and aligned, the boiler response lag characteristic quantity in the load rise delay parameter matched with the time stamp is extracted, the pressure decay characteristic quantity in the load drop inertia parameter matched with the time stamp is synchronously analyzed, and the effective interval of the dynamic stability correction factor is calibrated;

[0022] Q2, according to the working condition state marked by the calibrated dynamic stability correction factor, the boiler fuel compensation basis quantity is generated by driving the regular stability factor when the load instruction is in the regular load stage, and the turbine governing valve compensation basis quantity is generated by combining the peak regulation coupling influence factor when the load instruction is in the deep peak regulation stage;

[0023] Q3, for the boiler response lag characteristic quantity, the boiler fuel dynamic compensation value is generated by superimposing the boiler fuel compensation basis quantity and the pressure decay characteristic quantity; for the pressure decay characteristic quantity, the turbine governing valve dynamic compensation value is generated by correlating the turbine governing valve compensation basis quantity and the boiler response lag characteristic quantity;

[0024] Q4, the boiler fuel dynamic compensation value and the steam turbine governing valve dynamic compensation value are verified by bidirectional supply and demand balance, when the deviation rate of the two exceeds the preset tolerance threshold, the preset cross feedback regulation is started, and a dynamic compensation signal for suppressing coupling oscillation is finally output.

[0025] The application is further provided that: the specific content of generating the optimal initial pressure target value in the adaptive sliding pressure optimization module is:

[0026] W1, based on the actual change trend of the main steam temperature, the feedwater flow and the environmental temperature parameters in the actual operation of the thermal power generating unit, the correlation influence characteristics of each parameter on the initial sliding pressure curve are extracted, and the theoretical reference pressure offset of the initial sliding pressure curve under different load points is calculated;

[0027] W2, the theoretical reference pressure offset and the current boiler heat storage capacity change in the thermal power generating unit are dynamically coupled, the actual change rate of the load demand is superimposed to generate a pressure adjustment gradient value, and the running initial pressure target value is generated according to the matching degree of the pressure adjustment gradient value and the theoretical reference pressure offset;

[0028] W3, the change amplitude of the running initial pressure target value and the preset historical correction value is compared, when the change amplitude exceeds the set margin, the preset correction coefficient updating mechanism is activated, the current running initial pressure instant correction value in the correction coefficient updating mechanism is taken as the new reference of the historical correction value, and the optimal running initial pressure target value is output.

[0029] The application is further provided that: in the coordinated control execution module, the dynamic compensation signal and the optimal running initial pressure target value are integrated into a unified control instruction, and the specific steps are:

[0030] H1, in the coordinated control execution module, a basic instruction carrying framework is established, the optimal running initial pressure target value is taken as a reference, a basic instruction carrier is generated in the basic instruction carrying framework, and a dynamic docking space of the dynamic compensation signal is configured on the basic instruction carrier;

[0031] H2, the boiler fuel dynamic compensation value and the steam turbine governing valve dynamic compensation value in the dynamic compensation signal are respectively injected into the dynamic docking space, and the pressure regulating coefficient in the basic instruction carrier matched with the working condition of the current load instruction is called, weighted balance operation is performed on the injected boiler fuel dynamic compensation value and the steam turbine governing valve dynamic compensation value, and a pre-verified instruction combination is generated;

[0032] H3, the boiler fuel control target and the turbine governing valve control target in the instruction combination are subjected to coordinated convergence calculation through a preset instruction fusion algorithm, and when the dynamic coordination deviation of the boiler fuel control amount change rate and the turbine governing valve opening change rate is within a preset permission interval, a unified control instruction is output.

[0033] The application is further provided as follows: the specific working content of the compensation reinforcement mechanism in the coordinated control execution module is:

[0034] F1, when the pressure change rate constraint unit detects that the main steam pressure fluctuation on the boiler side of the thermal power generating unit exceeds a preset threshold, the compensation reinforcement mechanism is activated, and a pressure compensation instruction is generated according to the amplitude and change direction of the main steam pressure fluctuation on the boiler side of the thermal power generating unit;

[0035] F2, the pressure compensation instruction is superimposed on the unified control instruction output by the coordinated control execution module to form a compensated instruction, and the compensated instruction is synchronously output to a preset terminal in real time through a preset communication protocol;

[0036] F3, the terminal drives the combustion regulation system on the boiler side of the thermal power generating unit to change the main steam flow based on the fuel instruction component of the compensated instruction, and controls the turbine governing valve opening change rate based on the turbine governing valve instruction component of the compensated instruction;

[0037] F4, the terminal monitors the main steam pressure change curve on the boiler side of the thermal power generating unit and the actual load data of the unit in real time, and when it is detected that the main steam pressure fluctuation amplitude on the boiler side of the thermal power generating unit is within a preset target fluctuation range for three consecutive sampling periods and the actual load tracking deviation rate is lower than a permission threshold, the compensation reinforcement mechanism control is released and switched to the basic control mode of the coordinated control execution module.

[0038] The beneficial effects of the application are as follows:

[0039] 1. The application compensates the dynamic coupling effect between the boiler and the steam turbine through a dynamic coupling compensation module, combines the real-time closed-loop cooperative control mechanism of the coordinated control execution module, significantly reduces the hysteresis effect of the traditional PID regulation under deep peak shaving conditions, and quickly converges the main steam pressure fluctuation amplitude to the target range; at the same time, the instruction fusion algorithm based on error phase space reinforces the response synchronization of the boiler-steam turbine double system, greatly improves the load instruction tracking ability of the unit under low load peak shaving conditions, and significantly reduces the need for manual intervention.

[0040] 2.The application reconfigures the pressure operation reference value of different load points intelligently by analyzing the dynamic influence characteristics of the main steam temperature, feed water flow and ambient temperature on the sliding pressure curve in real time; and combines the dynamic threshold triggering mechanism of the pressure change rate constraint unit to make the initial sliding pressure curve adapt to the actual operation condition change autonomously, effectively eliminates the pressure fluctuation problem when the unit responds to the load instruction, and improves the system stability under the load peak regulation condition. BRIEF DESCRIPTION OF DRAWINGS

[0041] Figure 1 It is a system structure diagram of the application;

[0042] Figure 2 It is a load data acquisition flowchart of the application;

[0043] Figure 3 It is a dynamic compensation signal generation step flowchart of the application;

[0044] Figure 4 It is an optimal operation initial pressure target value generation step flowchart of the application. DETAILED DESCRIPTION

[0045] The preferred embodiments of the application will be described in detail below with reference to the accompanying drawings, so that the advantages and characteristics of the application can be more easily understood by those skilled in the art, and the protection scope of the application can be more clearly and definitely defined.

[0046] Please refer to Figures 1-4 A dynamic coupling compensation coordination control system of a thermal power unit, comprising: a dynamic coupling compensation module, an adaptive sliding pressure optimization module and a coordination control execution module, wherein the dynamic coupling compensation module, the adaptive sliding pressure optimization module and the coordination control execution module are all communicatively connected;

[0047] The dynamic coupling compensation module receives the load instruction issued by the preset control terminal, and according to the load instruction, through the preset acquisition unit, real-time acquires the main steam flow on the boiler side, the throttle opening on the turbine side and the load data key parameter set of the thermal power unit, and according to the load data key parameter set, automatically generates a dynamic compensation signal;

[0048] The acquisition of the load data key parameter set in the dynamic coupling compensation module includes the following steps:

[0049] S1, the acquisition unit synchronously acquires the load value in the load data key parameter set of the thermal power unit on the boiler side, the throttle opening on the turbine side and the load data key parameter set when the load instruction is issued;

[0050] The acquisition unit synchronously triggers three parallel acquisition channels within a millisecond time window after receiving the load instruction issuing signal: the first channel intercepts the 4-20mA analog signal of the main steam flow transmitter in the boiler system of the thermal power unit at a sampling interval of 10ms, and outputs the digital flow value through the AD conversion module; the second channel directly connects the turbine control cabinet through hardwiring, acquires the actual opening voltage signal fed back by the turbine governing valve displacement sensor and converts it into a percentage opening value; the third channel reads the load value of the power meter of the generator set from the thermal power unit system in real time through the communication protocol;

[0051] S2, when the change rate of the load value exceeds the set threshold, the acquisition unit acquires the fluctuation extreme value of the main steam flow on the boiler side and the action time difference of the turbine governing valve every second, if the change rate of the current load value is within the threshold range, the acquisition unit continuously acquires the peak-to-trough interval time length and the stable recovery time of the main steam flow on the boiler side; wherein, the "threshold range" specifically refers to the change rate of the load value being in the interval of 2%~10% / min (not including the end point value), at this time the system is in quasi-steady state condition;

[0052] S3, dynamically weighted fusion of the data collected by the acquisition unit according to the change direction of the load value: in the load value rising stage, the fluctuation extreme value of the main steam flow on the boiler side and the action time difference of the turbine governing valve opening degree in the thermal power unit are given high weight, and the load rising delay parameter representing the boiler response lag characteristic quantity is generated; in the load value descending stage, the peak-to-trough interval time length of the main steam flow is given high weight, and the load descending inertia parameter representing the pressure decay characteristic quantity is generated; at the same time, the stable recovery time is combined to construct a dynamic stability correction factor, and finally the load data key parameter set is output.

[0053] Wherein, the specific steps of constructing the dynamic stability correction factor and outputting the load data key parameter set in step S3 are as follows:

[0054] The stable recovery time value collected in the acquisition step S2 is normalized, and different weighting strategies are selected according to the change direction of the current load value: when the load instruction rises, the stable recovery time is time-coupled with the load rise delay parameter for analysis, the correlation characteristics of the stable recovery time and the peak decay rate of the main steam flow fluctuation are extracted, and the first type of stability influence factor is generated; when the load value decreases, the stable recovery time is related to the peak-to-trough interval time decay rate in the load drop inertia parameter, the linear inertia characteristics of the pressure fluctuation duration are extracted, and the second type of stability influence factor is generated; based on the real-time operation condition label of the thermal power unit, the first type of stability influence factor or the second type of stability influence factor is activated, the slowly varying fluctuation characteristics in the threshold range of the load value change rate are fused to generate the feature vector of the dynamic stability correction factor, and finally the load rise delay parameter, the load drop inertia parameter and the dynamic stability correction factor with the working condition label are integrated to form the key parameter set with the feature weight.

[0055] The specific steps of outputting the load data key parameter set in step S3 are as follows:

[0056] S31, in the regular load stage of the load instruction, the linear mapping relationship between the fluctuation extreme value of the main steam flow on the boiler side of the thermal power unit and the peak-to-trough interval time is established, and the regular characteristic parameter is output; in the deep peak regulation stage of the load instruction, the correlation strength of the load rise delay parameter and the stable recovery time is strengthened, and the action time difference of the turbine regulating valve opening degree on the boiler side of the thermal power unit is related to the load drop inertia parameter, and the deep peak regulation characteristic parameter is output;

[0057] The specific steps of establishing the linear mapping relationship and outputting the regular characteristic parameter in step S31 are as follows:

[0058] The peak and valley data points of the continuous fluctuation period are extracted from the main steam flow fluctuation extreme value collected in step S2, and the peak-to-trough interval time record sequence corresponding to the time stamp is related; a fluctuation intensity description vector is constructed based on the amplitude difference characteristics of the peak and valley data points, and the peak-to-trough interval time record sequence is converted into a period feature vector; a linear cooperative evolution rule library of the fluctuation intensity description vector and the period feature vector is established, and the matching correlation coefficient of the fluctuation intensity change rate and the interval time decay rate in the rule library is extracted; the dynamic linear mapping rule is generated according to the sample segment with the matching correlation coefficient greater than the preset standard, and the rule is applied to the calculation of the integrated value label of the regular characteristic parameter by applying the rule to the real-time collected fluctuation extreme value sequence;

[0059] S32, the fluctuation propagation rate of the main steam flow on the boiler side of the thermal power unit is extracted for the regular characteristic parameter, and is marked as a regular stability factor; the load rise delay parameter and the load drop inertia parameter are coupled for the deep peak regulation characteristic parameter to generate a peak regulation coupling influence factor;

[0060] S33. Integrate the conventional stability factor and the peak-shaving coupling influencing factor, combine them with the working condition type label of the current load instruction, generate a dynamic stability correction factor with a working condition identification, and finally output a set of key load data parameters including load rise delay parameters, load fall inertia parameters and dynamic stability correction factors.

[0061] The time-varying characteristics of the actual operating parameters of the thermal power unit in the adaptive sliding pressure optimization module include main steam temperature, feed water flow and ambient temperature.

[0062] The steps for generating the dynamic compensation signal in the dynamic coupling compensation module are as follows:

[0063] Q1. Perform timestamp alignment on the key parameter set of load data, extract the boiler response lag characteristic from the timestamp-matched load rise delay parameter, and simultaneously analyze the pressure decay characteristic from the timestamp-matched load fall inertia parameter. Also, calibrate the effective range of the dynamic stability correction factor.

[0064] The specific operation of extracting the boiler response hysteresis characteristic in step Q1 is as follows:

[0065] First, a millisecond-level timestamp alignment operation is performed on the key parameter set of load data, and a load increase delay parameter set with overlapping timestamps and in the load instruction increase stage is selected; the time difference between the moment when the extreme value of the main steam flow fluctuation on the boiler side reaches the peak and the actual opening response peak of the turbine throttle is analyzed from the parameter set, and the time difference is converted into a dynamic hysteresis feature vector through a time delay-hysteresis conversion model; at the same time, the number of mutation points of the main steam flow increase rate and the position of the acceleration inflection point of the throttle opening in the corresponding time window are extracted, and the number of mutation points and the position of the acceleration inflection point are associated to generate a response fault identification factor; the dynamic hysteresis feature vector and the response fault identification factor are integrated to output the boiler response hysteresis feature carrying the timestamp and hysteresis intensity;

[0066] Q2. Based on the operating condition marked by the calibrated dynamic stability correction factor, when the load instruction is in the normal load stage, the conventional stability factor is driven to generate the boiler fuel compensation base amount. When the load instruction is in the deep peak load stage, the peak load coupling influence factor is combined to generate the turbine throttle compensation base amount.

[0067] Q3. Based on the boiler response lag characteristic, the boiler fuel compensation base amount is superimposed on the pressure decay characteristic to generate a boiler fuel dynamic compensation value; based on the pressure decay characteristic, the turbine throttle compensation base amount is associated with the boiler response lag characteristic to generate a turbine throttle dynamic compensation value;

[0068] The specific steps for generating the boiler fuel dynamic compensation value in step Q3 are: inputting the boiler fuel compensation base quantity and the pressure decay characteristic quantity into a dynamic weight distributor, first analyzing the main steam pressure drop rate inflection point distribution and the valley value residence time length in the pressure decay characteristic quantity, calculating the pressure decay dynamic influence weight proportion based on the inflection point distribution density and the valley value residence time length; simultaneously extracting the fuel supply rate increment reference contained in the boiler fuel compensation base quantity, establishing a time delay matching correction factor of the fuel supply rate increment reference and the pressure decay dynamic influence weight proportion; dividing the pressure decay characteristic quantity into a positive buffer segment and a negative suppression segment through the time delay matching correction factor, applying an exponential gain coefficient to the positive buffer segment to generate a first compensation component by superimposing the fuel supply rate increment reference, and applying an inertial damping coefficient to the negative suppression segment to generate a second compensation component; finally performing time domain convolution fusion on the first compensation component and the second compensation component, and outputting the boiler fuel dynamic compensation value carrying the pressure decay adaptive weight.

[0069] Q4, the boiler fuel dynamic compensation value and the steam turbine governing valve dynamic compensation value are verified by bidirectional supply and demand balance, when the deviation rate exceeds the preset tolerance threshold (dynamic supply and demand matching deviation critical value of boiler fuel compensation demand and steam turbine governing valve compensation demand), the preset cross feedback adjustment is started, and finally the dynamic compensation signal for suppressing coupled oscillation is output.

[0070] An adaptive sliding pressure optimization module, the adaptive sliding pressure optimization module, based on the time-varying characteristics of the actual operation parameters of the thermal power unit, real-time corrects the preset initial sliding pressure curve, and superimposes the current load demand of the thermal power unit and the change of the boiler heat storage capacity in the initial sliding pressure curve, dynamically generates an optimal operation initial pressure target value;

[0071] Among them, the specific content of the optimal operation initial pressure target value generated in the adaptive sliding pressure optimization module is:

[0072] W1, based on the actual change trend of the main steam temperature, the feedwater flow and the environmental temperature parameters in the actual operation of the thermal power unit, the associated influence characteristics of each parameter on the initial sliding pressure curve are extracted, and the theoretical reference pressure offset of the initial sliding pressure curve under different load points is calculated;

[0073] The calculation method of the theoretical reference pressure offset is as follows: three types of characteristic parameters of the real-time running of the thermal power generating unit, i.e., the main steam temperature change gradient, the feed water flow fluctuation period and the environmental temperature deviation from the reference value amplitude, are extracted, and the associated influence coefficients of each type of parameter on the initial sliding pressure curve corresponding to the load point are calculated respectively; the main steam temperature change gradient characteristic is mapped to the first pressure offset factor output by the steam turbine thermal efficiency correction model, the feed water flow fluctuation period is input to the second pressure offset factor output by the boiler heat storage dynamic equation, and the environmental temperature deviation amplitude is loaded into the third pressure offset factor output by the heat dissipation compensation algorithm; the first, second and third pressure offset factors are subjected to time and space superposition integration through the three-factor synergistic action field model to generate a pressure compensation spectrum distribution map of the initial sliding pressure curve under different load conditions; a theoretical reference pressure offset curve is generated based on the compensation extreme value position connecting line in the spectrum distribution map of each load point, and finally a load point-offset mapping set is output;

[0074] W2, dynamically coupling the theoretical reference pressure offset with the current boiler heat storage capacity change in the thermal power generating unit, superimposing the actual change rate of the load demand to generate a pressure adjustment gradient value, and generating a running initial pressure target value according to the matching degree of the pressure adjustment gradient value and the theoretical reference pressure offset;

[0075] W3, comparing the change amplitude of the running initial pressure target value and the preset historical correction value, when the change amplitude exceeds the set margin, activating the preset correction coefficient updating mechanism, taking the current running initial pressure instant correction value in the correction coefficient updating mechanism as the new reference of the historical correction value, and outputting the optimal running initial pressure target value.

[0076] The coordination control execution module is configured to integrate the dynamic compensation signal and the optimal running initial pressure target value into a unified control instruction, and set a pressure change rate constraint unit. When the pressure fluctuation of the pipeline where the main steam flow on the boiler side of the thermal power generating unit exceeds the preset threshold, the preset compensation reinforcement mechanism is activated: a pressure compensation instruction is generated based on the amplitude and change direction of the pressure fluctuation of the pipeline where the main steam flow on the boiler side of the thermal power generating unit; the pressure compensation instruction is superimposed on the unified control instruction to form a compensated instruction, and the compensated instruction is synchronized to the preset terminal to control the main steam flow on the boiler side and the valve opening degree on the turbine side of the thermal power generating unit, and track the load data key parameter set of the thermal power generating unit.

[0077] In the coordination control execution module, the dynamic compensation signal and the optimal running initial pressure target value are integrated into a unified control instruction, and the specific steps are as follows:

[0078] H1, a basic instruction bearing framework is established in the coordination control execution module, and a basic instruction carrier is generated in the basic instruction bearing framework based on the optimal running initial pressure target value, and a dynamic docking space of the dynamic compensation signal is configured on the basic instruction carrier;

[0079] H2, the boiler fuel dynamic compensation value in the dynamic compensation signal and the turbine governing valve dynamic compensation value are respectively injected into the dynamic docking space, and the pressure regulating coefficient in the basic instruction carrier matched with the working condition of the current load instruction is called to perform weighted balance operation on the injected boiler fuel dynamic compensation value and the turbine governing valve dynamic compensation value, to generate a pre-verified instruction combination;

[0080] H3, the boiler fuel control target and the turbine governing valve control target in the instruction combination are subjected to coordinated convergence calculation through a preset instruction fusion algorithm, and when the dynamic coordination deviation of the boiler fuel control amount change rate and the turbine governing valve opening change rate is within a preset permission interval, a unified control instruction is output.

[0081] The boiler fuel control target and the turbine governing valve control target in the instruction combination are subjected to coordinated convergence calculation through a preset instruction fusion algorithm, specifically:

[0082] An error phase space of the boiler fuel control amount change rate trajectory and the turbine governing valve opening change rate trajectory is established, and the gradient offset angle of the boiler fuel control target sequence and the oscillation attenuation rate of the turbine governing valve control target sequence in the instruction combination are extracted; a double-track target coordination traversal operation is performed in the error phase space: the gradient offset angle is mapped into an input vector of a phase difference correction channel, and the oscillation attenuation rate is input into a damping allowance balance channel; a non-linear covariance minimization calculation is performed on the input vector and the damping allowance balance channel output value through a dynamic coupling factor, and when the fluctuation amplitude of the gradient offset angle is within a preset permission interval for three consecutive calculation periods and the fluctuation frequency of the oscillation attenuation rate decreases to a preset stable frequency band, it is determined that the boiler fuel control target and the turbine governing valve control target reach a coordinated convergence state.

[0083] The specific working content of the compensation reinforcement mechanism in the coordinated control execution module is:

[0084] F1, when the pressure change rate constraint unit detects that the main steam pressure fluctuation on the boiler side of the thermal power unit exceeds a preset threshold, the compensation reinforcement mechanism is activated, and a pressure compensation instruction is generated according to the amplitude and change direction of the main steam pressure fluctuation on the boiler side of the thermal power unit;

[0085] F2, the pressure compensation instruction is superimposed on the unified control instruction output by the coordinated control execution module to form a compensated instruction, and the compensated instruction is real-time synchronized to a preset terminal through a preset communication protocol;

[0086] F3, the terminal drives the boiler combustion regulation system on the boiler side of the thermal power unit to change the main steam flow based on the fuel instruction component of the boiler side in the compensated instruction, and controls the turbine governing valve opening change rate based on the turbine governing valve instruction component in the compensated instruction;

[0087] F4, the terminal real-time monitors the main steam pressure change curve of the boiler side in the thermal power generating unit and actual load data, when it is detected that the main steam pressure fluctuation amplitude of the boiler side in the thermal power generating unit is in the preset target fluctuation range for three continuous sampling periods and the actual load tracking deviation rate is lower than the permitted threshold value, the compensation reinforcement mechanism control is released and the basic control mode of the coordinated control execution module is switched.

[0088] Example 1: 300MW subcritical unit deep peaking condition

[0089] Under the deep peaking condition of a certain 300MW subcritical unit, the load instruction is reduced from 180MW to 120MW at a rate of 12% / min, the acquisition unit detects that the change rate exceeds the threshold value, and then collects the main steam flow fluctuation extreme value (peak value 8.5MPa, valley value 7.2MPa) and the time difference of the valve action (2.8 seconds) every second, while the S3 stage generates the load drop inertia parameter; the adaptive sliding pressure module calculates the 40% load point pressure offset +0.6MPa based on the feedwater flow fluctuation period (28 seconds) and the environmental temperature mutation (15℃→5℃) through the three-factor coordination model; the dynamic coupling compensation module divides the pressure decay characteristic quantity into a positive buffer segment (the first 10 seconds) in the Q3 stage and applies a 1.3 times exponential gain to generate a boiler fuel dynamic compensation value, and the coordinated control execution module calculates in the H3 error phase space to make the gradient offset angle stable in the ±0.5rad permission interval, finally the compensation reinforcement mechanism detects that the main steam pressure fluctuation is stable in the ±0.4MPa target range for three continuous periods, and the load tracking deviation rate is 0.8% lower than the 1.5% threshold value, and the reinforcement control is released.

[0090] Example 2: 600MW supercritical unit load climbing condition

[0091] A certain 600MW supercritical unit responds to the AGC instruction to increase from 480MW to 540MW at a rate of 9% / min, the S2 stage collects the main steam flow peak-to-valley interval length (peak value 950t / h, valley value 820t / h, period 42 seconds) and the stable recovery time (18 seconds), and the S32 converts the instruction rising response segment recovery time into a 1.25 times time efficiency weight coefficient and superimposes it on the conventional stability factor; the sliding pressure optimization module generates a 60% load point pressure offset of-0.3MPa based on the main steam temperature gradient (2℃ / s) through the thermal efficiency correction model; the Q4 stage verifies the supply and demand of the boiler fuel dynamic compensation value (+12.8t / h) and the steam turbine valve compensation value (+9.6%), and when the deviation rate 1.7% exceeds the 1.5% tolerance threshold, the cross feedback adjustment is started; the H3 instruction fusion algorithm reduces the oscillation decay rate fluctuation frequency to 0.05Hz stable frequency band in the error phase space, and after the coordinated convergence, the pressure change rate constraint unit monitors that the pressure fluctuation amplitude keeps the target range of ±0.35MPa for three continuous periods, and the load tracking accuracy reaches 98.6%.

[0092] The above merely illustrates the embodiments of the present application, and is not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process conversion, or direct or indirect application in other related technical fields, which is made according to the content of the present application, shall be included in the patent protection scope of the present application.

Claims

1. A dynamic coupling compensatory coordinated control system for a thermal power unit, characterized by: include: Dynamic coupling compensation module, adaptive sliding pressure optimization module and coordinated control execution module; A dynamic coupling compensation module receives a load instruction from a preset control terminal and, based on the load instruction, collects in real time the main steam flow rate on the boiler side of the thermal power unit, the throttle valve opening on the turbine side, and a set of key load data parameters of the thermal power unit through a preset collection unit, and automatically generates a dynamic compensation signal based on the set of key load data parameters; The adaptive sliding pressure optimization module, based on the time-varying characteristics of the actual operating parameters of the thermal power unit, modifies the preset initial sliding pressure curve in real time, and superimposes the current load demand of the thermal power unit and the change in the boiler's heat storage capacity on the initial sliding pressure curve to dynamically generate the optimal operating initial pressure target value; a coordinated control execution module, configured to integrate the dynamic compensation signal and the optimal operating initial pressure target value into a unified control instruction, and simultaneously set a pressure change rate constraint unit, so that when the pressure fluctuation of the main steam flow pipeline on the boiler side of the thermal power unit exceeds a preset threshold, a preset compensation enhancement mechanism is activated: a pressure compensation instruction is generated based on the amplitude and change direction of the pressure fluctuation of the main steam flow pipeline on the boiler side of the thermal power unit; the pressure compensation instruction is superimposed on the unified control instruction to form a compensated instruction; the compensated instruction is synchronized to a preset terminal, the main steam flow on the boiler side of the thermal power unit and the throttle opening on the turbine side are controlled, and a set of key load data parameters of the thermal power unit are tracked; The acquisition of the key parameter set of load data in the dynamic coupling compensation module includes the following steps: S1, the collection unit synchronously collects the main steam flow rate on the boiler side of the thermal power unit, the throttle valve opening on the turbine side, and the load value in the key parameter set of the load data of the thermal power unit in real time when the load instruction is issued; S2. When the rate of change of the load value exceeds a set threshold, the collection unit collects the fluctuation extreme value of the main steam flow on the boiler side and the time difference between the turbine throttle action every second. If the current rate of change of the load value is within the threshold range, the collection unit continuously collects the peak-to-trough interval length and the stable recovery time of the main steam flow on the boiler side; S3. Dynamically weighting and fusing the data collected by the collection unit according to the direction of change of the load value: During the load value rising phase, the time difference between the extreme fluctuation of the main steam flow rate on the boiler side of the thermal power unit and the action time of the turbine throttle opening is assigned a high weight to generate a load rise delay parameter representing the boiler response lag characteristic; during the load value falling phase, the duration of the peak and trough intervals of the main steam flow rate is assigned a high weight to generate a load fall inertia parameter representing the pressure decay characteristic; and a dynamic stability correction factor is constructed based on the stable recovery time, and finally a set of key load data parameters is output; The specific steps of outputting the key parameter set of load data in step S3 are as follows: S31. When the load instruction is in the normal load stage, a linear mapping relationship between the fluctuation extreme value of the main steam flow rate on the boiler side of the thermal power unit and the peak-to-trough interval length is established, and a normal characteristic parameter is output; when the load instruction is in the deep peak-shaving stage, the correlation strength between the load rise delay parameter and the stable recovery time is strengthened, and the action time difference of the turbine throttle valve opening on the boiler side of the thermal power unit is correlated with the load drop inertia parameter, and a deep peak-shaving characteristic parameter is output; S32. Extract the fluctuation propagation rate of the main steam flow rate on the boiler side of the thermal power unit based on the conventional characteristic parameters and mark it as a conventional stability factor; and generate a peak-shaving coupling influence factor by coupling the load rise delay parameter and the load fall inertia parameter based on the deep peak-shaving characteristic parameters; S33. Integrate the conventional stability factor and the peak-shaving coupling influence factor, combine them with the working condition type label of the current load instruction, generate a dynamic stability correction factor with a working condition identifier, and ultimately output a set of key load data parameters including a load rise delay parameter, a load fall inertia parameter, and a dynamic stability correction factor; The steps for generating the dynamic compensation signal in the dynamic coupling compensation module are as follows: Q1. Perform timestamp alignment on the key parameter set of the load data, extract the boiler response lag characteristic from the load rise delay parameter that matches the timestamp, synchronously analyze the pressure decay characteristic from the load fall inertia parameter that matches the timestamp, and calibrate the effective range of the dynamic stability correction factor. Q2. Based on the operating condition marked by the calibrated dynamic stability correction factor, when the load command is in the normal load stage, the normal stability factor is driven to generate a boiler fuel compensation base amount; when the load command is in the deep peak load stage, the peak load coupling influence factor is combined to generate a turbine throttle compensation base amount; Q3. Based on the boiler response lag characteristic, the boiler fuel compensation base amount is superimposed on the pressure decay characteristic to generate a boiler fuel dynamic compensation value; based on the pressure decay characteristic, the turbine throttle compensation base amount is associated with the boiler response lag characteristic to generate a turbine throttle dynamic compensation value; Q4. Performing a bidirectional supply-demand balance verification on the boiler fuel dynamic compensation value and the turbine throttle dynamic compensation value. When the deviation rate between the two exceeds a preset tolerance threshold, a preset cross-feedback adjustment is initiated, and a dynamic compensation signal that suppresses coupled oscillation is ultimately output; The specific content of generating the optimal operating initial pressure target value in the adaptive sliding pressure optimization module is: W1. Based on the actual change trends of the main steam temperature, feed water flow rate, and ambient temperature parameters during actual operation of the thermal power unit, extract the correlation and influence characteristics of each parameter on the initial sliding pressure curve, and calculate the theoretical reference pressure offset of the initial sliding pressure curve at different load points; W2. Dynamically couple the theoretical reference pressure offset with the change in the current boiler heat storage capacity of the thermal power unit, and superimpose the actual rate of change of the load demand to generate a pressure adjustment gradient value. Based on the degree of matching between the pressure adjustment gradient value and the theoretical reference pressure offset, an initial operating pressure target value is generated; W3. Compare the change range of the initial operating pressure target value with the preset historical correction value. When the change range exceeds the set margin, activate the preset correction coefficient update mechanism, use the current initial operating pressure instant correction value in the correction coefficient update mechanism as the new benchmark of the historical correction value, and output the optimal initial operating pressure target value.

2. A thermal power unit dynamic coupling compensatory coordinated control system according to claim 1, characterized in that: The time-varying characteristics of the actual operating parameters of the thermal power unit in the adaptive sliding pressure optimization module include main steam temperature, feed water flow rate and ambient temperature.

3. A thermal power unit dynamic coupling compensatory coordinated control system according to claim 2, characterized in that: The coordinated control execution module integrates the dynamic compensation signal and the optimal operation initial pressure target value into a unified control instruction, and the specific steps are as follows: H1. Establishing a basic instruction carrier framework in the coordinated control execution module, generating a basic instruction carrier within the basic instruction carrier framework based on the optimal initial operating pressure target value, and configuring a dynamic docking space for the dynamic compensation signal on the basic instruction carrier; H2. Injecting the boiler fuel dynamic compensation value and the turbine throttle dynamic compensation value in the dynamic compensation signal into the dynamic docking space respectively, and simultaneously calling the pressure adjustment coefficient in the basic instruction carrier that matches the working condition of the current load instruction, performing a weighted balancing operation on the injected boiler fuel dynamic compensation value and the turbine throttle dynamic compensation value to generate a pre-verified instruction combination; H3. A coordinated convergence calculation is performed on the boiler fuel control target and the turbine throttle control target in the command combination through a preset command fusion algorithm. When the dynamic coordinated deviation between the boiler fuel control quantity change rate and the turbine throttle opening change rate is within a preset allowable range, a unified control command is output.

4. A thermal power unit dynamic coupling compensatory coordinated control system according to claim 3, characterized in that: The specific working content of the compensation reinforcement mechanism in the coordinated control execution module is: F1. When the pressure change rate constraint unit detects that the main steam pressure fluctuation on the boiler side of the thermal power unit exceeds a preset threshold, the compensation enhancement mechanism is activated to generate a pressure compensation instruction according to the amplitude and change direction of the main steam pressure fluctuation on the boiler side of the thermal power unit; F2. Superimposing the pressure compensation instruction onto the unified control instruction output by the coordinated control execution module to form a compensated instruction, and synchronizing the compensated instruction to a preset terminal in real time through a preset communication protocol; F3, the terminal drives the combustion regulation system on the boiler side of the thermal power unit to change the main steam flow rate based on the fuel instruction component on the boiler side in the compensated instruction, and controls the rate of change of the turbine throttle valve opening based on the turbine throttle valve instruction component in the compensated instruction; F4. The terminal monitors the main steam pressure change curve and actual load data of the boiler side of the thermal power unit in real time. When it is detected that the main steam pressure fluctuation amplitude on the boiler side of the thermal power unit is within the preset target fluctuation range for three consecutive sampling periods and the actual load tracking deviation rate is lower than the permitted threshold, the compensation enhancement mechanism control is released and the basic control mode of the coordinated control execution module is switched.

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