CN-122001013-A - Automatic power generation scheduling control method and device for thermal power generating unit

CN122001013ACN 122001013 ACN122001013 ACN 122001013ACN-122001013-A

Abstract

The invention provides an automatic power generation scheduling control method and device of a thermal power generating unit, and relates to the technical field of intelligent power grids, wherein the method comprises the steps of collecting multisource observation data of an electric side and a combustion side of a hearth, extracting a negative pressure fluctuation amplitude of the hearth, a flame centroid jitter amplitude and a sound pressure fluctuation amplitude to construct an acoustic-combustion coupling stability index, and establishing a coal consumption cost function and an emission cost function by combining historical unit operation data; dividing an acoustic-combustion coupling stability domain according to an acoustic-combustion coupling stability index, monitoring an ascending trend, taking an acoustic-combustion coupling risk as a scheduling constraint triggering condition, reconstructing a scheduling optimization model in a risk leading scene, taking active output, a coal mill combination and air distribution parameters as decision variables, solving an optimal track by taking physical limits, grid side constraints and stability domains as limiting conditions, and finally issuing to a coordination control layer. The invention can actively deviate from the output curve in the acoustic-combustion coupling instability risk rising stage so as to avoid acoustic resonance, thereby guaranteeing the dynamic scheduling capability of the unit.

Inventors

LI XIAOPING
XING LIJUN
SUN CHAO
Sheng Xiaozhi
JIA LIFENG
AN YAN
JI HONGFEI
ZHANG SHENGFENG
YANG JIE
ZHOU CHUNYANG
LI SU
ZHAO XIAOQIANG
LI SHAOGANG
TAN QI
ZHANG BENGUO
ZHAO YANKAI
Geng Shifu
LI KAILUN
LI XINGMIN
SONG JIHU
XU BAOXING
ZHANG YANQI

Assignees

华电莱州发电有限公司
青岛国瑞信息技术有限公司

Dates

Publication Date: 20260508
Application Date: 20260116

Claims (10)

1. An automatic power generation scheduling control method of a thermal power generating unit is characterized by comprising the following steps: collecting multisource observation data of a power side and a combustion side of a hearth; Preprocessing the multi-source observation data to extract a hearth negative pressure fluctuation amplitude, a flame centroid jitter amplitude and a sound pressure fluctuation amplitude, and constructing a sound-combustion coupling stability index; the method comprises the steps of constructing a coal consumption cost function and an emission cost function of a unit based on historical operation data, and realizing prediction of fuel consumption and emission changes of the unit under different active output, different coal mill combinations and different secondary air distribution modes; Dividing an acoustic-combustion coupling stability domain according to acoustic-combustion coupling stability indexes under different active power output, different coal mill combinations and different secondary air distribution modes, setting an operating point for inducing acoustic-combustion coupling instability as a forbidden domain, and setting an operating point at an acoustic-combustion coupling instability boundary as a risk domain; When the time sequence of the acoustic-fire coupling stability index shows a continuous ascending trend and the corresponding working point is positioned at the boundary of the risk domain or the forbidden domain, the current scheduling scene is identified as an acoustic-fire coupling constraint leading scene; Reconstructing a dispatching optimization model in the acoustic-combustion coupling constraint dominant scene, taking a set value of active output of a unit, a start-stop state of a coal mill and distribution of primary air volume and secondary air volume as decision variables, constructing an optimization target based on the unit coal consumption cost function and the emission cost function, and taking a unit physical limit, a power grid side constraint and the acoustic-combustion coupling stability domain as optimization constraints; And issuing the optimal active output track, the optimal coal mill combination and the optimal primary air and secondary air distribution track obtained by solving the dispatching optimization model to a coordination control layer, so that the thermal power unit can avoid an acoustic sensitive working condition and maintain dispatching control when the acoustic-combustion coupling instability risk rises.
2. The automatic power generation scheduling control method of a thermal power generating unit according to claim 1, wherein the preprocessing of the multi-source observation data is performed to extract a negative pressure fluctuation amplitude of a hearth, a flame centroid jitter amplitude and a sound pressure fluctuation amplitude, and construct a sound-combustion coupling stability index, and specifically comprises: Aiming at a hearth negative pressure time sequence, a sound pressure time sequence and a flame video sequence, executing unified time reference alignment and resampling on the same time axis, so that a hearth negative pressure discrete sequence, a sound pressure discrete sequence and a flame image frame sequence are in one-to-one correspondence at each discrete time; Performing trending treatment and band-pass filtering treatment on the hearth negative pressure discrete sequence, and obtaining an effective value of the band-pass filtering sequence in a sliding time window to represent hearth negative pressure fluctuation amplitude of the hearth acoustic mode frequency band related pressure fluctuation intensity; performing trending treatment and band-pass filtering treatment on the sound pressure discrete sequence, constructing an analysis signal by the band-pass filtering sequence, extracting an envelope amplitude, and obtaining a sound pressure fluctuation amplitude for representing the acoustic oscillation intensity of the hearth by calculating an average envelope amplitude in a sliding time window; performing graying, denoising and brightness normalization processing on the flame video sequence, extracting a burner flame region, performing weighted summation on pixel brightness of the flame region to obtain flame centroid coordinates, and calculating offset of the flame centroid relative to a time average position in a sliding time window to obtain flame centroid shaking amplitude used for representing the integral swinging and morphological drift degree of the flame; Performing normalization processing on the hearth negative pressure fluctuation amplitude, the sound pressure fluctuation amplitude and the flame centroid jitter amplitude according to the reference amplitude and the fluctuation range of the hearth negative pressure fluctuation amplitude, the flame centroid jitter amplitude and the sound pressure fluctuation amplitude which are obtained through statistics under the stable combustion working condition; And combining the normalized hearth negative pressure fluctuation amplitude, flame centroid jitter amplitude and sound pressure fluctuation amplitude according to a weighting and nonlinear amplification mode to form the acoustic-combustion coupling stability index.
3. The automatic power generation scheduling control method of a thermal power generating unit according to claim 1, wherein the construction of the unit coal consumption cost function and the emission cost function based on the historical operation data realizes the prediction of the fuel consumption and the emission change of the unit under different active output, different coal mill combinations and different secondary air distribution modes, and specifically comprises the following steps: Establishing a working condition database comprising an active power output time sequence, a fuel accumulated consumption record, a coal mill start-stop state sequence and a primary air volume and secondary air volume distribution record, and carrying out association marking on an active power output average value, a coal mill combination state and secondary air distribution mode in each stable operation time period and fuel consumption increment and emission monitoring increment in a corresponding time period to form a historical working condition sample set; Establishing a functional relation between an equivalent fuel consumption rate and working condition characteristics according to a fuel consumption increment and an active power output average value in each stable operation time window, a coal mill combination state and a secondary air distribution mode in the historical working condition sample set, obtaining a unit coal consumption cost function through parameter optimization, and predicting fuel consumption change of the unit coal consumption cost function according to the active power output, the coal mill combination state and the secondary air distribution mode; Establishing a functional relation between a comprehensive emission index and a working condition characteristic in the historical working condition sample set according to an emission concentration average value in each stable operation time window, an active output average value in the time window, a coal mill combination state and a secondary air distribution mode, obtaining an emission cost function through parameter optimization, and predicting emission change according to the active output, the coal mill combination state and the secondary air distribution mode by the emission cost function; In the real-time operation process, the active output set value, the coal mill combination and the secondary air distribution mode which are output by the dispatching optimization are sequentially input into the unit coal consumption cost function and the emission cost function as input variables to obtain the fuel consumption cost value and the emission cost value of each candidate working condition in the future time domain, and the fuel consumption change and the emission change are quantitatively represented in the dispatching optimization objective function, so that the dispatching control predicts the fuel consumption change and the emission change under different working conditions according to the unit coal consumption cost function and the emission cost function.
4. The automatic power generation scheduling control method of a thermal power generating unit according to claim 1, wherein the dividing of the acoustic-combustion coupling stability domain according to the acoustic-combustion coupling stability indexes under different active power output, different coal mill combinations and different secondary air distribution modes, setting the operating point of induced acoustic-combustion coupling instability as a forbidden domain, and setting the operating point at the boundary of acoustic-combustion coupling instability as a risk domain comprises the following specific steps: Based on the real-time calculation result of the acoustic-combustion coupling stability index, constructing an acoustic-combustion coupling sample set covering different active forces, different coal mill combinations and different secondary air distribution modes, and recording active forces, coal mill combinations, secondary air distribution modes and corresponding acoustic-combustion coupling stability index time sequences on each working point; Collecting all sound-fire coupling stability index samples in a sliding time window for each combined working condition which is determined by an active power output interval, a coal mill combined code and a secondary air distribution mode; calculating a sample average value and a sample standard deviation according to the acoustic-combustion coupling stability index sample; constructing an effective acoustic-fire coupling stability evaluation value based on the sample average value and the sample standard deviation; Comparing the effective acoustic-combustion coupling stability evaluation value according to a preset stability upper limit threshold value and a risk upper limit threshold value, and marking the combined working condition as a stable working condition point when the effective acoustic-combustion coupling stability evaluation value corresponds to below the stability upper limit threshold value; marking the combined working condition as a risk working condition point when the effective acoustic-combustion coupling stability evaluation value is between a stability upper limit threshold value and a risk upper limit threshold value, and marking the combined working condition as a forbidden working condition point when the effective acoustic-combustion coupling stability evaluation value exceeds the risk upper limit threshold value; mapping the stable working condition point, the risk working condition point and the forbidden working condition point to a multidimensional working condition space and forming an acoustic-combustion coupling stability domain, wherein the multidimensional working condition space takes active output, a coal mill combination and a secondary air distribution mode as independent variables.
5. The automatic power generation scheduling control method of a thermal power generating unit according to claim 1, wherein when the time sequence of the acoustic-combustion coupling stability index shows a continuous rising trend and the corresponding working condition point is located at the boundary of the risk domain or the forbidden domain, the method specifically comprises the steps of: Executing monotonicity and increasing amplitude analysis between a plurality of continuous sampling points on the time sequence by utilizing a sliding time window, and judging that the time sequence has continuous rising trend when the acoustic-combustion coupling stability index of the plurality of continuous sampling points is larger than or equal to the acoustic-combustion coupling stability index of the previous sampling point and the increment of the acoustic-combustion coupling stability index of the current sampling point relative to the acoustic-combustion coupling stability index of the initial sampling point of the local time window exceeds a preset rising threshold; Mapping a current working point to the acoustic-combustion coupling stability domain according to a current moment active power output set value, a current coal mill combination and a current secondary air distribution mode, and judging the working point of the current working point belonging to a stable domain, a risk domain or a forbidden domain boundary; And when the time sequence has continuous ascending trend and the current working point belongs to a risk domain or a working point belonging to a forbidden domain boundary, marking the current scheduling scene as the acoustic-combustion coupling constraint dominant scene.
6. The automatic power generation scheduling control method of a thermal power generating unit according to claim 1, wherein the reconstructing and scheduling optimization model in the acoustic-combustion coupling constraint dominant scene takes a unit active output set value, a coal mill start-stop state, and primary air volume and secondary air volume distribution as decision variables, constructs an optimization target based on the unit coal consumption cost function and the emission cost function, and takes a unit physical limit, a power grid side constraint and the acoustic-combustion coupling stability domain as optimization constraints, and specifically comprises: dispersing a rolling optimization time domain according to a uniform time length, and taking a set value of active output of a unit, a start-stop state of a coal mill and distribution of primary air volume and secondary air volume in each dispersing period as decision variables to be optimized; The unit coal consumption cost function and the emission cost function are respectively applied to decision variable sets of each scheduling period to calculate fuel consumption cost value and comprehensive emission cost value, deviation of a unit active output set value relative to an automatic power generation control active output instruction forms an automatic power generation control tracking cost value, and acoustic-combustion coupling stability penalty cost values constructed according to the acoustic-combustion coupling stability index are jointly used as cost items in an optimization target; The method comprises the steps of taking the minimum stable output of a unit, the maximum rated output of the unit, the climbing rate of the unit, the minimum continuous operation time and the minimum shutdown time of a coal mill, the upper limit and the lower limit of the total air quantity of primary air and the total air quantity of secondary air and the upper limit and the lower limit of the distribution proportion of the air quantity of secondary air as physical limit constraints of the unit, taking the active balance of a power grid, the spare capacity requirement and the frequency modulation assessment constraint as power grid side constraints, taking the working condition combination corresponding to the forbidden working condition point in the acoustic-combustion coupling stability domain as a forbidden value, and taking the time continuous residence of the working condition combination corresponding to the risk working condition point as the acoustic-combustion coupling stability domain constraint.
7. The automatic power generation scheduling control method of a thermal power generating unit according to claim 1, wherein the optimal active output track, the optimal coal mill combination and the optimal primary air and secondary air distribution track obtained by solving the scheduling optimization model are issued to a coordination control layer to adjust the operation of a boiler combustion system and a turbine system, so that the thermal power generating unit can avoid an acoustic sensitive working condition and maintain scheduling control when the acoustic-combustion coupling instability risk rises, and the method specifically comprises the following steps: Performing smoothing treatment and consistency check on the optimal active output track, the optimal coal mill combined track, the optimal primary air and the secondary air distribution track, so that the active output change of adjacent time steps meets the climbing speed limit of a unit, and the primary air and secondary air distribution change meets the corresponding relation of the start-stop state of the coal mill; Transmitting the processed optimal active output track, the optimal coal mill combined track and the optimal primary air and secondary air distribution track to a coordination control layer, and decomposing the optimal active output track into a main boiler setting, a steam turbine regulating opening setting and a generator excitation voltage setting in the coordination control layer; converting the optimal coal mill combination track into a start-stop command and load lifting rate setting for each coal mill; converting the optimal primary air and the secondary air distribution track into primary air fan and secondary air fan output and combustor layer and side wall air door baffle opening setting; And in the process of executing the issuing track by the coordination control layer, feedforward and feedback correction is carried out on the optimal primary air and secondary air distribution track according to the indexes of the negative pressure, the oxygen quantity, the smoke temperature and the acoustic-combustion coupling stability of the real-time hearth, and when the indexes of the acoustic-combustion coupling stability are not reduced as expected, the optimal active output setting and the optimal coal mill are combined to execute adjustment, so that the boiler combustion system and the steam turbine system avoid acoustic sensitive working conditions and maintain scheduling control under the condition of rising risk of acoustic-combustion coupling instability.
8. An automatic power generation scheduling control device of a thermal power generating unit, which is used for executing the automatic power generation scheduling control method of the thermal power generating unit according to any one of claims 1-7, and comprises an acquisition module, a processing module and an output module, wherein: The acquisition module is used for acquiring multisource observation data of the electric side and the combustion side of the hearth; The processing module is used for preprocessing the multi-source observation data to extract the negative pressure fluctuation amplitude of the hearth, the flame centroid jitter amplitude and the sound pressure fluctuation amplitude, and constructing a sound-combustion coupling stability index; The processing module is used for constructing a coal consumption cost function and an emission cost function of the unit based on historical operation data, and realizing the prediction of the fuel consumption and emission change of the unit under different active output, different coal mill combinations and different secondary air distribution modes; the processing module is used for dividing the acoustic-combustion coupling stability domain according to the acoustic-combustion coupling stability indexes under different active power output, different coal mill combinations and different secondary air distribution modes, setting the working point of induced acoustic-combustion coupling instability as a forbidden domain, and setting the working point at the boundary of acoustic-combustion coupling instability as a risk domain; The processing module is used for identifying the current scheduling scene as a sound-combustion coupling constraint dominant scene when the time sequence of the sound-combustion coupling stability index shows a continuous ascending trend and the corresponding working point is positioned at the boundary of the risk domain or the forbidden domain; The processing module is used for reconstructing a dispatching optimization model in the acoustic-combustion coupling constraint dominant scene, taking a set value of active output of a unit, a start-stop state of a coal mill and primary air volume and secondary air volume distribution as decision variables, constructing an optimization target based on the unit coal consumption cost function and the emission cost function, and taking a unit physical limit, a power grid side constraint and the acoustic-combustion coupling stability domain as optimization constraints; The output module is used for sending the optimal active output track, the optimal coal mill combination and the optimal primary air and secondary air distribution track obtained by solving the dispatching optimization model to the coordination control layer, so that the thermal power generating unit can avoid the acoustic sensitive working condition and maintain dispatching control when the acoustic-combustion coupling instability risk rises.
9. An electronic device comprising a processor, a communication bus, a user interface, a network interface, and a memory, the memory for storing instructions, the user interface and the network interface each for communicating with other devices, the communication bus for enabling connection communications between components within the electronic device, the processor for executing instructions stored in the memory to cause the electronic device to perform the method of any of claims 1-7.
10. A non-transitory computer readable storage medium storing instructions which, when executed, perform the method of any of claims 1-7.

Description

Automatic power generation scheduling control method and device for thermal power generating unit Technical Field The invention relates to the technical field of smart power grids, in particular to an automatic power generation scheduling control method and device of a thermal power generating unit. Background The power generation dispatching control of the thermal power generating unit generally relies on an automatic power generation control system, active power output of the unit is dynamically adjusted according to power grid load requirements and unit coal consumption characteristics, the unit is enabled to run along an output curve as far as possible on the premise of meeting power grid frequency stability constraint and reserve capacity constraint, a coal mill start-stop strategy and an air supply system are combined to adjust and maintain combustion efficiency, meanwhile continuous emission monitoring data are used as auxiliary feedback to achieve comprehensive balance of economy and environmental friendliness, a dispatching side generally regards the unit as a quasi-steady-state power source limited by climbing speed, and power grid side frequency modulation and peak regulation targets are achieved through optimization of active power output set values. Under the condition that the combustion system is subjected to strong disturbance acoustic coupling of the hearth, for example, the hearth is subjected to low-frequency oscillation due to rapid change of the pulverized coal shade along with wind deviation, and the automatic power generation scheduling control needs to deviate from an output curve temporarily. In the prior art, the scheduling layer lacks explicit modeling and constraint on the combustion-acoustic coupling state in the unit hearth, so that automatic power generation scheduling still forces tracking instructions according to economic priority logic when the load frequently fluctuates or a coal mill combination and an air distribution combination fall into an acoustic sensitive area, the amplification of hearth negative pressure, combustion noise and flame form low-frequency oscillation is easy to induce, combustion instability and rapid emission are caused, even protection of a furnace shutdown is triggered, an output curve cannot be deviated in time in the rising stage of acoustic-combustion coupling instability risk, and acoustic resonance working conditions are avoided, so that the dynamic scheduling capability of a thermal power unit under complex disturbance is not sufficiently ensured. Disclosure of Invention The invention provides an automatic power generation scheduling control method and device for a thermal power generating unit, which can actively deviate from an output curve to avoid acoustic resonance in the acoustic-combustion coupling instability risk rising stage, so that the dynamic scheduling capability of the unit is ensured. In a first aspect of the present invention, there is provided an automatic power generation scheduling control method of a thermal power generating unit, the method comprising: collecting multisource observation data of a power side and a combustion side of a hearth; Preprocessing the multi-source observation data to extract a hearth negative pressure fluctuation amplitude, a flame centroid jitter amplitude and a sound pressure fluctuation amplitude, and constructing a sound-combustion coupling stability index; the method comprises the steps of constructing a coal consumption cost function and an emission cost function of a unit based on historical operation data, and realizing prediction of fuel consumption and emission changes of the unit under different active output, different coal mill combinations and different secondary air distribution modes; Dividing an acoustic-combustion coupling stability domain according to acoustic-combustion coupling stability indexes under different active power output, different coal mill combinations and different secondary air distribution modes, setting an operating point for inducing acoustic-combustion coupling instability as a forbidden domain, and setting an operating point at an acoustic-combustion coupling instability boundary as a risk domain; When the time sequence of the acoustic-fire coupling stability index shows a continuous ascending trend and the corresponding working point is positioned at the boundary of the risk domain or the forbidden domain, the current scheduling scene is identified as an acoustic-fire coupling constraint leading scene; Reconstructing a dispatching optimization model in the acoustic-combustion coupling constraint dominant scene, taking a set value of active output of a unit, a start-stop state of a coal mill and distribution of primary air volume and secondary air volume as decision variables, constructing an optimization target based on the unit coal consumption cost function and the emission cost function, and taking a unit physical limit, a power grid side constraint an