Control method and system for capacity-increasing transformation of induced draft fan of unit

Abstract

The invention provides a unit induced draft fan capacity increasing transformation control method and system, and the method comprises the steps: expanding a DCS system hardware channel, deploying an anti-interference communication link, adapting to the multi-source measurement and control demands of a two-stage movable blade adjustable induced draft fan, and completing the hardware resource reconstruction; a weight-adjustable collaborative algorithm of the two-stage moving blade and the frequency converter is constructed in the reconstructed DCS, and the dynamic change of the negative pressure of the boiler is responded; generating a progressive interlocking protection instruction based on the dynamic change of the negative pressure of the boiler in combination with fusion analysis of the vibration spectrum, the oil pressure gradient and the position feedback of an execution mechanism; the protection instruction is executed, the operation state of the fans on the two sides is diagnosed in real time, and air volume balance under the fault of the single fan is achieved through flue damper linkage and movable blade compensation; after air volume balance is achieved, a load disturbance scene is simulated in a unit maintenance window, and a movable blade-air volume control curve is calibrated; and according to the control curve, actual operation energy consumption data is determined, the weight of the collaborative algorithm is dynamically corrected, and the capacity increasing transformation effect of the induced draft fan of the unit is effectively improved.

Description

Technical Field

[0001] This invention relates to the field of induced draft fan capacity expansion technology, and in particular to a control method and system for induced draft fan capacity expansion and retrofitting. Background Technology

[0002] In the field of induced draft fan capacity expansion and retrofitting, with the continuous development of technology, the requirements for induced draft fan control methods are becoming increasingly stringent. Currently, two-stage adjustable induced draft fans are widely used in various types of units; however, the supporting control systems still face many problems when dealing with complex operating conditions. For example, the existing DCS system hardware channels and communication links are difficult to adapt to the multi-source measurement and control requirements of two-stage adjustable induced draft fans, resulting in the inability to obtain various operating parameters of the induced draft fan in a timely and accurate manner during unit operation, thus affecting the effective control of the induced draft fan. Furthermore, when facing dynamic changes in boiler negative pressure, existing control algorithms struggle to achieve efficient coordination between the two-stage blades and the frequency converter, resulting in insufficient adjustment accuracy and response speed of the induced draft fan, failing to meet the requirements for stable unit operation. More seriously, when a single fan fails, existing control methods cannot quickly achieve airflow balance, potentially leading to serious consequences such as unit instability or even shutdown.

[0003] Therefore, how to improve the capacity expansion and retrofit effect of the induced draft fan of the unit has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0004] This invention provides a control method and system for upgrading and modifying the induced draft fan of a power unit, which solves the defect of poor capacity expansion effect of the induced draft fan in the prior art.

[0005] In a first aspect, the present invention provides a control method for capacity expansion and retrofitting of a generator unit's induced draft fan, comprising:

[0006] Expand the hardware channels of the DCS system and deploy anti-interference communication links to adapt to the multi-source measurement and control requirements of the dual-stage adjustable blade induced draft fan and complete the hardware resource reconstruction;

[0007] In the reconstructed DCS, a weighted and adjustable collaborative algorithm for two-stage moving blades and frequency converters is constructed to respond to dynamic changes in boiler negative pressure.

[0008] Based on the dynamic changes in the boiler negative pressure, combined with the fusion analysis of vibration spectrum, oil pressure gradient and actuator position feedback, a progressive interlocking protection command is generated.

[0009] The protection command is executed to diagnose the operating status of both fans in real time, and to achieve air volume balance under single fan failure through the linkage of flue damper and blade compensation.

[0010] After achieving air volume balance, simulate load disturbance scenarios in the unit maintenance window and calibrate the blade-air volume control curve.

[0011] Based on the control curve, the actual operating energy consumption data is determined, and the weights of the collaborative algorithm are dynamically adjusted.

[0012] According to the present invention, a control method for capacity expansion and retrofitting of a generator induced draft fan includes, wherein the deployment of an anti-interference communication link comprises:

[0013] Configure an independent shielded twisted-pair channel for the high-frequency vibration sensor;

[0014] Install a signal isolation barrier on the DCS side to suppress electromagnetic interference;

[0015] A dedicated data transmission channel for wind turbine control was established based on a fiber optic ring network.

[0016] The independent shielded twisted-pair channel, the signal isolation barrier, and the dedicated data transmission channel form a complete anti-interference system.

[0017] According to the present invention, a control method for capacity expansion and retrofitting of a generator unit's induced draft fan includes a weighted adjustable cooperative algorithm comprising:

[0018] The dynamic response range of the boiler negative pressure change rate is divided into a high-speed response range and a low-speed response range;

[0019] In the high-speed response range, blade angle adjustment is assigned as the main control weight, and in the low-speed response range, inverter adjustment is assigned as the main control weight.

[0020] According to the control method for capacity expansion and retrofitting of a generator unit's induced draft fan provided by the present invention, the switching method of the main control weight is as follows:

[0021] Real-time calculation of the deviation between the air volume setpoint and the actual output;

[0022] The weighting coefficients of the moving blades and the frequency converter are dynamically adjusted based on the aforementioned deviation.

[0023] When the deviation continues to increase and exceeds the threshold, the emergency adjustment mode of the moving blade angle is forcibly switched to complete the main control weight switch.

[0024] According to the present invention, a control method for capacity expansion and retrofitting of a generator induced draft fan includes the following fusion analysis:

[0025] The vibration spectrum is decomposed using wavelet packet decomposition to extract characteristic frequency band energy;

[0026] Based on the oil pressure gradient, a time series prediction model for the rate of change of the oil pressure gradient is established to predict oil pressure.

[0027] When both the characteristic frequency band energy and the oil pressure prediction result exceed the limit, an intermediate response is triggered to generate a progressive interlocking protection command.

[0028] According to the present invention, a control method for capacity expansion and retrofitting of a generator induced draft fan includes generating progressive interlocking protection commands, comprising:

[0029] Generate primary, intermediate, and advanced responses;

[0030] The primary response is to: increase the power of the lubricating oil station cooler and adjust the oil pressure setting value;

[0031] The intermediate response is executed as follows: gradually reduce the blade opening of the abnormal wind to a safe level;

[0032] The advanced response is executed as follows: the fan is tripped and the intercom damper is opened to release pressure.

[0033] The method for controlling the capacity expansion and retrofit of a generator unit's induced draft fan according to the present invention further includes:

[0034] Collect stall critical state spectrum data during historical operation;

[0035] Extract the amplitude-frequency correlation features from the spectrum data to form a unit-specific stall fingerprint database;

[0036] The real-time spectrum is matched with the fingerprint database for similarity.

[0037] According to the present invention, a control method for capacity expansion and retrofitting of a generator unit's induced draft fan is provided, wherein the air volume balance under single fan failure is achieved through flue damper linkage and blade compensation, comprising:

[0038] Calculate the theoretical airflow gap on the side of the faulty fan;

[0039] Based on the dynamic gap value and the theoretical air volume gap, the upper limit of the operating fan blade opening is increased, and the opening of the connecting damper is adjusted simultaneously to balance the flue resistance and achieve air volume balance.

[0040] According to a control method for capacity expansion and retrofitting of a generator unit's induced draft fan provided by the present invention, the dynamic correction of the weights of the cooperative algorithm includes:

[0041] Based on the control curve and historical operating energy consumption data, a three-dimensional relationship surface between blade angle, air volume, and power consumption is established.

[0042] Based on the actual operating energy consumption data, the control points of the three-dimensional relational surface are iteratively updated, and the minimum slope of the surface is used as the optimization target of the weight coefficient to correct the weight of the collaborative algorithm.

[0043] Secondly, the present invention also provides a control system for the capacity expansion and retrofitting of a generator induced draft fan, comprising:

[0044] The reconfiguration module is used to expand the hardware channels of the DCS system and deploy anti-interference communication links to adapt to the multi-source measurement and control requirements of the dual-stage adjustable blade induced draft fan and complete the hardware resource reconfiguration.

[0045] The coordination module is used to build a weighted adjustable coordination algorithm between the two-stage moving blades and the frequency converter in the reconstructed DCS to respond to dynamic changes in boiler negative pressure.

[0046] The fusion module is used to generate progressive interlocking protection commands based on the dynamic changes of the boiler negative pressure, combined with the fusion analysis of vibration spectrum, oil pressure gradient and actuator position feedback.

[0047] The balancing module is used to execute the protection command, diagnose the operating status of both fans in real time, and achieve air volume balance under single fan failure through flue damper linkage and blade compensation.

[0048] The calibration module is used to calibrate the blade-airflow control curve by simulating load disturbance scenarios in the unit maintenance window after achieving airflow balance.

[0049] The correction module is used to determine the actual operating energy consumption data according to the control curve and dynamically correct the weights of the collaborative algorithm.

[0050] Thirdly, the present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the unit induced draft fan capacity expansion and modification control method as described above.

[0051] Fourthly, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the unit induced draft fan capacity expansion and modification control method as described above.

[0052] Fifthly, the present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the unit induced draft fan capacity expansion and modification control method as described above.

[0053] The present invention provides a control method and system for the capacity expansion and retrofit of induced draft fans in a generating unit, comprising: expanding the hardware channels of the DCS system and deploying an anti-interference communication link to adapt to the multi-source measurement and control requirements of a dual-stage adjustable blade induced draft fan, and completing hardware resource reconfiguration; constructing a weighted adjustable collaborative algorithm for dual-stage blades and frequency converters in the reconfigured DCS to respond to dynamic changes in boiler negative pressure; generating progressive interlocking protection commands based on dynamic changes in boiler negative pressure, combined with the fusion analysis of vibration spectrum, oil pressure gradient, and actuator position feedback; executing the protection commands, diagnosing the operating status of both fans in real time, and achieving airflow balance under single fan failure through flue damper linkage and blade compensation; after achieving airflow balance, simulating load disturbance scenarios in the unit maintenance window and calibrating the blade-airflow control curve; determining the actual operating energy consumption data according to the control curve, dynamically correcting the weights of the collaborative algorithm, and through resource reconfiguration, adapting to multi-source measurement and control requirements, achieving collaboration between dual-stage blades and frequency converters under negative pressure, and achieving airflow balance, effectively improving the capacity expansion and retrofit effect of the induced draft fan in the generating unit. Attached Figure Description

[0054] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0055] Figure 1 This is a flowchart illustrating the control method for capacity expansion and modification of the induced draft fan of the unit provided in this embodiment;

[0056] Figure 2 This is a schematic diagram of the structure of the unit induced draft fan capacity expansion and modification control device provided in this embodiment;

[0057] Figure 3 This is a schematic diagram of the structure of the electronic device provided in this embodiment. Detailed Implementation

[0058] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0059] Figure 1 This is a flowchart illustrating the control method for capacity expansion and modification of the induced draft fan of the unit provided in this embodiment.

[0060] like Figure 1As shown, the unit induced draft fan capacity expansion and retrofit control method provided in this embodiment of the invention mainly includes the following steps:

[0061] 101. Expand the hardware channels of the DCS system and deploy anti-interference communication links to adapt to the multi-source measurement and control requirements of the dual-stage adjustable blade induced draft fan, and complete the hardware resource reconstruction.

[0062] Specifically, in the capacity expansion and modification of the induced draft fan, adapting to the multi-source measurement and control requirements of the two-stage adjustable blade induced draft fan necessitates the reconstruction of the DCS system hardware resources. Specifically, to expand the DCS system hardware channels, suitable input / output modules can be selected based on the DCS system architecture and the number and signal types of various sensors and actuators of the two-stage adjustable blade induced draft fan. When the existing module channels are insufficient, the number of hardware channels can be expanded by adding modules of the same type or selecting modules with higher channel density. For example, in some complex industrial scenarios, where the original DCS system control modules face insufficient output channels, relay arrays can be used to connect to the DCS output ports, thereby controlling more external devices and effectively expanding the system's I / O capabilities.

[0063] When deploying anti-interference communication links, configuring an independent shielded twisted-pair channel for high-frequency vibration sensors is a crucial step. High-frequency vibration sensors generate high-frequency signals during operation, making them susceptible to external electromagnetic interference. An independent shielded twisted-pair cable provides a dedicated transmission path. The shielding layer blocks external electromagnetic fields from interfering with the signal, and the twisted-pair structure effectively suppresses common-mode interference, ensuring the integrity and accuracy of the high-frequency vibration signal during transmission and reducing signal distortion and noise interference.

[0064] Installing signal isolation barriers on the DCS side to suppress electromagnetic interference is equally important. Signal isolation barriers are installed between the DCS system and field devices, electrically isolating input and output signals. In industrial environments, there are numerous sources of electromagnetic interference, such as electromagnetic noise generated by the start-up and shutdown of large motors and the operation of welding machines. Signal isolation barriers can block these interference signals from being transmitted to the DCS system through signal lines, protecting the DCS system's signal input and output modules, improving the system's anti-interference capability, and ensuring stable system operation.

[0065] Establishing a dedicated data transmission channel for wind turbine control based on a fiber optic ring network is a powerful measure to ensure reliable data transmission. Fiber optic ring networks are characterized by high transmission rates, large bandwidth, and strong resistance to electromagnetic interference. Compared to traditional cable transmission, fiber optics are unaffected by electromagnetic interference, enabling high-speed and stable data transmission. Constructing a dedicated data transmission channel avoids mutual interference between wind turbine control data and other system data during transmission, and the redundant structure of the fiber optic ring network can automatically switch data transmission paths when some links fail, ensuring the continuity of data transmission.

[0066] A complete anti-interference system is formed through independently shielded twisted-pair channels, signal isolation barriers, and dedicated data transmission channels. All components work collaboratively, from interference protection at the sensor signal acquisition end to interference blocking at the DCS system front end, and anti-interference assurance during data transmission, comprehensively improving the reliability and stability of multi-source measurement and control data transmission for the two-stage adjustable-blade induced draft fan. This enables the DCS system to accurately acquire various parameters of the induced draft fan's operation, providing a solid data foundation for subsequent control algorithm execution and stable system operation, ensuring accurate and efficient operation of the induced draft fan even under complex working conditions.

[0067] 102. Construct a weighted and adjustable collaborative algorithm for the two-stage moving blades and frequency converter in the reconstructed DCS to respond to dynamic changes in boiler negative pressure.

[0068] Specifically, firstly, the boiler negative pressure change rate needs to be divided into intervals. Through analysis of historical operating data and monitoring of actual operating conditions, a suitable threshold for the negative pressure change rate is determined. When the boiler negative pressure change rate exceeds this threshold, it is determined to have entered the high-speed response interval; conversely, it is in the low-speed response interval. For example, based on statistical analysis of a large amount of operating data, if a negative pressure change rate of ±50 Pa per minute is set as the threshold, then when the actual operating negative pressure change rate is greater than 50 Pa per minute or less than -50 Pa per minute, it is in the high-speed response interval; when it is between -50 Pa and 50 Pa per minute, it is in the low-speed response interval.

[0069] In the high-speed response range, due to the rapid changes in boiler negative pressure, the system's response speed is extremely critical. Therefore, blade angle adjustment is assigned as the primary control weight. This is because direct adjustment of the blade angle can quickly change the fan's airflow, thus affecting the pressure state within the furnace more rapidly. The specific value of the blade angle adjustment weight can be determined through experimental testing and theoretical calculation. For example, after multiple tests and optimizations under different operating conditions, it was determined that in the high-speed response range, the blade angle adjustment weight is set to 0.7, and the inverter adjustment weight is set to 0.3. This weight allocation allows the system to achieve optimal regulation performance in the high-speed response range.

[0070] In the low-speed response range, the boiler negative pressure changes relatively gradually, so the requirement for response speed is slightly lower, but energy saving and stability are more important. At this time, allocating inverter regulation as the main control weight, and adjusting the fan airflow by changing the motor speed, can effectively reduce energy consumption. Similarly, the specific values ​​of the inverter regulation weights need to be determined through extensive experiments and calculations. For example, in the low-speed response range, after repeated testing and optimization, the inverter regulation weight was set to 0.6, and the blade angle adjustment weight was set to 0.4 to ensure that the system achieves efficient and energy-saving operation while meeting regulation requirements.

[0071] During operation, the switching of the main control weight is crucial. The DCS system collects real-time data on the deviation between the air volume setpoint and the actual output. By analyzing and calculating the collected real-time data, the weight coefficients of the blades and the frequency converter are dynamically adjusted. When the deviation continues to increase and exceeds a preset threshold, the system will forcibly switch to the blade angle emergency adjustment mode, completing the switching of the main control weight. For example, if the preset air volume deviation threshold is ±10%, when it is found that the deviation between the air volume setpoint and the actual output continues to increase and exceeds 10% during actual operation, the system immediately activates the blade angle emergency adjustment mode, rapidly increasing the blade angle adjustment weight to 0.9 or even higher to correct the air volume deviation as soon as possible and stabilize the furnace negative pressure.

[0072] This weighted, adjustable collaborative algorithm delivers significant results. When faced with dynamic changes in boiler negative pressure, it can precisely adjust the collaborative operation of the two-stage impeller and the frequency converter according to different rates of change. In the high-speed response range, impeller angle adjustment is the primary method, rapidly responding to negative pressure changes and ensuring the stability of the furnace negative pressure, effectively avoiding problems such as unstable combustion and flameout caused by excessive negative pressure fluctuations. In the low-speed response range, frequency converter adjustment is the primary method, reducing fan operating energy consumption and improving the unit's economy. Simultaneously, through real-time monitoring of airflow deviation and intelligent switching of main control weights, the system's adaptability to complex operating conditions is enhanced, ensuring efficient and precise control of the induced draft fan under various circumstances, thus improving the reliability and stability of the entire unit's operation.

[0073] 103. Based on the dynamic changes in boiler negative pressure, combined with the fusion analysis of vibration spectrum, oil pressure gradient and actuator position feedback, a progressive interlocking protection command is generated.

[0074] Specifically, in the process of generating progressive interlocking protection commands based on the dynamic changes in boiler negative pressure, the vibration spectrum, oil pressure gradient, and actuator position feedback must first be integrated and analyzed.

[0075] For the vibration spectrum, wavelet packet decomposition is employed. Since the vibration signal from a wind turbine contains a wealth of information reflecting its operating state, wavelet packet decomposition can break down the complex vibration spectrum signal into multiple different sub-bands. In practice, appropriate wavelet basis functions (such as the db series wavelets) and the number of decomposition levels are selected to process the acquired vibration spectrum signal. After decomposition, the energy of each sub-band is calculated, i.e., the characteristic frequency band energy is extracted. Different fault types or abnormal operating states will exhibit significant energy changes in specific frequency bands, allowing for the sensitive detection of abnormal signs in the wind turbine's vibration state.

[0076] Regarding oil pressure gradients, a time series prediction model for the rate of change of the oil pressure gradient needs to be established for oil pressure forecasting. First, actual oil pressure gradient data over a period of time is collected, forming a time series. Based on the data characteristics and fluctuation patterns, a suitable time series prediction model is selected, such as the Autoregressive Integral Moving Average (ARIMA) model or a Long Short-Term Memory (LSTM) network. If an ARIMA model is chosen, the stationarity of the oil pressure gradient rate of change time series needs to be tested first to determine the model's autoregressive order (p), differencing order (d), and moving average order (q). Through training on historical data, the model can learn the trends and patterns of oil pressure gradient changes, thereby predicting future oil pressure.

[0077] When the characteristic frequency band energy and the predicted oil pressure both exceed a preset threshold, the system will trigger an intermediate response, which in turn generates a progressive interlocking protection command. The progressive interlocking protection command is divided into three levels: primary response, intermediate response, and advanced response.

[0078] During the initial response, the system detects potential abnormalities in the fan operation, but these have not yet reached a critical level. At this time, the system automatically increases the power of the lubrication oil station cooler to enhance the cooling effect of the lubricating oil and prevent a decline in lubrication performance due to increased oil temperature. Simultaneously, the system adjusts the oil pressure setpoint to better meet the fan's safe operation requirements under current conditions, maintaining good lubrication of all components and reducing wear and the risk of failure.

[0079] When the fault condition further develops and both the characteristic frequency band energy and oil pressure prediction results exceed the limits, the system enters an intermediate response phase. At this point, the system gradually reduces the abnormal fan blade opening to a safe range. By precisely controlling the blade opening, the fan's airflow and pressure are adjusted to bring the fan's operating parameters back to a safe range, preventing equipment damage due to the continued development of the abnormal operating condition.

[0080] If the abnormal situation cannot be effectively controlled and the fan's operating status deteriorates significantly, the system will execute an advanced response. At this time, the system will trip the faulty fan immediately to prevent further escalation and more serious damage to the equipment. Simultaneously, the connecting damper will be opened to release pressure, quickly releasing the pressure within the pipeline to ensure the safety of the entire system and prevent other safety accidents caused by excessive pressure.

[0081] This method of generating progressive interlocking protection commands based on multi-parameter fusion analysis can comprehensively and accurately monitor the operating status of the wind turbine. By executing protection commands in stages and levels, when anomalies occur in the wind turbine, timely measures can be taken for adjustment and protection to prevent small problems from escalating into major failures. In extreme cases, the source of the fault can be quickly cut off, ensuring the safe and stable operation of the entire unit, effectively reducing the equipment failure rate, and improving the reliability and safety of the unit's operation.

[0082] 104. Execute protection commands, diagnose the operating status of both fans in real time, and achieve air volume balance under single fan failure through flue damper linkage and blade compensation.

[0083] Specifically, during the execution of protection commands, the reconstructed DCS system first collects operating parameters such as vibration, wind pressure, and current of both fans in real time, and uses a preset diagnostic model to determine whether a fan fault exists. When a fault is detected in one fan, the single-fan fault airflow balance control logic is immediately activated.

[0084] When calculating the theoretical airflow gap on the side of the faulty fan, the average airflow of the fan on the faulty side in the 30 seconds before the fault occurred is used as the baseline value. This is then subtracted from the actual output airflow of the fan on that side after the fault (which is usually zero). The resulting difference is the theoretical airflow gap that needs to be filled. For example, if the average airflow of the fan before the fault was 8000 m³ / s... 3 / h, after the fault the actual air volume is 0, then the theoretical air volume gap is 8000m³ / h. 3 / h.

[0085] Based on the theoretical airflow gap calculated above, the DCS system automatically increases the upper limit of the operating fan's blade opening—for example, if the original upper limit is 70%, it can be dynamically increased to 85%–90% depending on the size of the gap. This allows the operating fan to increase its output by increasing the blade opening, thus compensating for the airflow gap. Simultaneously, the system adjusts the opening of the connecting damper: if the faulty side is the left-side fan, the left-side flue damper is gradually closed while the connecting damper is opened, adjusting the resistance distribution of the flue on both sides by changing the flue flow area, allowing the airflow output from the operating fan to be more smoothly distributed throughout the flue. During this process, the DCS monitors the deviation between the total airflow and the target airflow in real time, dynamically fine-tuning the blade opening and damper opening until the deviation between the actual airflow and the total airflow before the fault is controlled within ±5%, achieving airflow balance.

[0086] This process, through precise calculation of air volume deficit and coordinated adjustment of moving blades and dampers, can quickly restore air volume balance within 10 to 15 seconds after a single fan failure. It avoids severe fluctuations in boiler negative pressure and unstable combustion caused by a sudden drop in air volume, significantly improving the unit's anti-interference capability and operational stability under sudden failures, buying valuable time for fault handling, and reducing the risk of unplanned shutdowns.

[0087] 105. After achieving air volume balance, simulate load disturbance scenarios in the unit maintenance window and calibrate the blade-air volume control curve.

[0088] Specifically, firstly, based on the unit's historical operating data and design parameters, simulated load disturbance scenarios are set. For example, simulating typical operating conditions such as the unit load rapidly increasing from 70% to 90% of the rated load, or suddenly dropping from full load to 50% of the rated load. The rate and magnitude of the simulated load changes are precisely controlled through the DCS system to closely match the sudden load changes that may be encountered in actual operation.

[0089] Next, before simulating load disturbances begins, ensure that all monitoring parameters of the DCS system are accurate, including key data such as the blade opening, air volume, air pressure, and current of both fans, as well as boiler negative pressure and steam flow. Simultaneously, record the blade opening and corresponding air volume values ​​under the current stable operating conditions as initial data for subsequent analysis.

[0090] During simulated load disturbances, the DCS system continuously and frequently acquires real-time airflow data for the blade openings of both fans. Data is acquired every 100 milliseconds to capture the dynamic relationship between instantaneous changes in blade opening and airflow response. As the load disturbance progresses, the fans adjust their blade openings to maintain system stability, and the DCS system records these changes synchronously. For example, when the simulated load increases, the fans need to increase airflow, and the blade opening gradually increases. The DCS system meticulously records the airflow value corresponding to each minute change in blade opening as it increases from 30% to 50%.

[0091] After the simulated load disturbance ended and the system stabilized again, the large amount of collected blade opening and airflow data was processed and analyzed. Data fitting algorithms, such as the least squares method, were used to fit these discrete data points, and a blade-airflow control curve was plotted. This curve visually demonstrates the changes in the actual output airflow of the fan under different blade openings.

[0092] After conducting multiple simulated load disturbance tests of different types and amplitudes, and repeating the above data acquisition and analysis process, multiple sets of blade-airflow control curves were obtained. These curves were compared, and the most representative and stable curves were selected as the final calibrated blade-airflow control curves, which were then stored in the DCS system database.

[0093] This method of calibrating the blade-airflow control curve by simulating load disturbance scenarios during unit maintenance has proven highly effective. On one hand, by simulating various load disturbance conditions that may occur in actual operation, it comprehensively and realistically reflects the relationship between blade opening and airflow under different operating conditions, improving the accuracy and applicability of the control curve. On the other hand, the precisely calibrated control curve provides an important reference for the unit's daily operation. Operators can precisely adjust the blade opening based on real-time load demands according to this curve, enabling the fan's output airflow to quickly and accurately match system requirements. This improves the stability and response speed of unit operation, effectively avoiding problems such as combustion instability and reduced unit efficiency caused by improper airflow adjustment, thus ensuring the safe and efficient operation of the unit.

[0094] 106. Based on the control curve, determine the actual operating energy consumption data and dynamically adjust the weights of the collaborative algorithm.

[0095] Specifically, in determining actual operating energy consumption data and dynamically adjusting the weights of the collaborative algorithm, the first step is to construct a three-dimensional relationship surface between blade angle, airflow, and power consumption based on the calibrated blade-airflow control curve and accumulated historical operating energy consumption data. From the historical operating data, blade angle, corresponding actual airflow, and power consumption data for different operating conditions are selected. For example, relevant data for the unit under different loads (e.g., 30%, 50%, 75%, 100% of rated load) are collected, with multiple sets of blade angle, airflow, and power consumption values ​​for each operating condition. Using these discrete data points, a suitable surface fitting algorithm, such as a multivariate polynomial fitting algorithm, is employed to construct a three-dimensional relationship surface with blade angle as one coordinate axis, airflow as another, and power consumption as the dependent variable. This surface can intuitively present the energy consumption of the fan under different combinations of blade angle and airflow.

[0096] As the unit continues to operate, real-time energy consumption data is constantly acquired. When new real-time operating data is generated, such as collecting the latest blade angle, airflow, and corresponding power consumption data every hour, this new data is incorporated into the existing data system. An iterative algorithm is used to update the control points of the three-dimensional relationship surface based on the new data. During the iteration process, minimizing the surface slope is the optimization objective. Because the surface slope reflects the rate of change in power consumption when the blade angle and airflow change, minimizing the surface slope means finding a blade angle and airflow adjustment relationship with the most gradual increase in energy consumption; that is, under this adjustment relationship, the increase in energy consumption is minimized when changing the blade angle and airflow. Through multiple iterative updates, the three-dimensional relationship surface can more accurately reflect the relationship between blade angle, airflow, and power consumption under the current operating state of the unit.

[0097] Based on the updated 3D relational surface, the weights of the dual-stage blade and inverter collaborative algorithm are adjusted according to the combination of blade angle and airflow adjustment corresponding to the minimum surface slope. For example, if surface analysis reveals that the surface slope is minimum under a certain operating condition when the blade angle is in the range of 40°-45° and the airflow is within a specific range, then the weights of blade adjustment and inverter adjustment in the collaborative algorithm need to be adjusted so that the system tends to maintain the blade angle within this range under that operating condition, while also coordinating with inverter adjustment to achieve the lowest energy consumption operating state.

[0098] This method of dynamically adjusting the weights of the collaborative algorithm based on actual operating energy consumption data has yielded significant results. By continuously optimizing the three-dimensional relationship surface between blade angle, air volume, and power consumption, the collaborative algorithm can adapt to changes in unit operating conditions in real time, precisely adjusting the collaborative working weights of the blades and the frequency converter. Under different loads and operating environments, it can guide the fan to operate in the most energy-efficient manner, effectively reducing fan energy consumption and improving the economic efficiency of unit operation. Simultaneously, because the algorithm can continuously self-optimize based on actual operating conditions, it enhances the system's adaptability to complex and changing operating conditions, ensuring the long-term, stable, and efficient operation of the unit.

[0099] Furthermore, based on the above embodiments, this embodiment also includes: collecting stall critical state spectrum data during historical operation; extracting amplitude-frequency correlation features from the spectrum data to form a unit-specific stall fingerprint database; and performing similarity matching between the real-time spectrum and the fingerprint database.

[0100] Specifically, firstly, during long-term operation of the unit, high-precision vibration sensors are used to locate measuring points at key parts of the wind turbine (such as the impeller and bearing housing) to collect vibration signals approaching the stall critical state under different operating conditions. These vibration signals contain rich information about the wind turbine's operating status. The sensors continuously collect signals at a high sampling frequency (e.g., 1000 times per second or higher, depending on the wind turbine type and operating characteristics) to ensure that subtle vibration changes can be captured. The collected raw time-domain vibration signals are transmitted to a data acquisition system, which converts the signals into digital form and stores them. Simultaneously, the Fast Fourier Transform (FFT) algorithm is used to transform the collected time-domain signals, converting them from the time domain to the frequency domain to obtain the corresponding spectral data. During the transformation process, the FFT parameters, such as the number of data points and the window function type (e.g., Hanning window, Hamming window), are set appropriately according to the signal characteristics to improve spectral resolution and accuracy, fully preserving the spectral characteristics under the stall critical state.

[0101] Next, amplitude-frequency correlation features are extracted from the acquired spectrum data to form a stall fingerprint database specific to the turbine. Signal processing algorithms are used to analyze the amplitude magnitude and distribution patterns of different frequency components in the spectrum data. For example, for some common wind turbine stall types, abnormal amplitude increases or fluctuations occur in specific frequency ranges. By setting appropriate thresholds and feature extraction rules, key frequency ranges related to stall and their corresponding amplitude change characteristics are selected. Taking a certain type of wind turbine as an example, analysis of a large amount of historical data revealed that at the stall critical state, the amplitude in the 100-150Hz frequency range increases significantly, and the amplitude change rate exceeds a certain threshold. These feature data are organized, classified, and stored according to a specific data structure to construct a stall fingerprint database specific to the turbine. This fingerprint database will be continuously updated and improved with new historical operating data to adapt to the slow changes in the operating characteristics of the turbine.

[0102] During the real-time operation of the unit, the current vibration signal of the wind turbine is continuously collected, and a fast Fourier transform is performed to obtain the real-time spectrum. The real-time spectrum is then matched with the feature data in the stall fingerprint database. A similarity calculation algorithm (such as Euclidean distance algorithm, cosine similarity algorithm, etc.) is used to calculate the similarity index between the real-time spectrum and each feature data in the fingerprint database. If the similarity index exceeds a preset threshold (e.g., 0.8, which is determined through historical data verification and actual operating experience), the current wind turbine operating state is determined to be close to or at the stall critical state, and the system immediately issues a warning signal.

[0103] This method, based on historical data collection, feature extraction and database construction, and real-time spectrum matching, effectively improves the accuracy and timeliness of wind turbine stall monitoring. Through the analysis and processing of a large amount of historical operating data, the constructed stall fingerprint database closely matches the actual operating characteristics of the unit, providing a precise reference standard for real-time monitoring. Rapid matching of the real-time spectrum with the fingerprint database can provide timely warnings before the wind turbine enters a stall state. Operators can then take preventative measures, such as adjusting the turbine's blade opening and optimizing load distribution, to avoid wind turbine stall failures, ensure the safe and stable operation of the unit, and reduce downtime and economic losses caused by wind turbine failures.

[0104] Based on the same general inventive concept, this invention also protects a unit induced draft fan capacity expansion and modification control system. The unit induced draft fan capacity expansion and modification control system described below and the unit induced draft fan capacity expansion and modification control method described above can be referred to in correspondence.

[0105] Figure 2 This is a schematic diagram of the structure of the unit induced draft fan capacity expansion and retrofit control system provided by the present invention.

[0106] like Figure 2 As shown in the figure, the unit induced draft fan capacity expansion and retrofit control system provided in this embodiment includes:

[0107] The reconfiguration module 210 is used to expand the hardware channels of the DCS system and deploy anti-interference communication links to adapt to the multi-source measurement and control requirements of the dual-stage adjustable blade induced draft fan and complete the hardware resource reconfiguration.

[0108] The coordination module 220 is used to build a weighted adjustable coordination algorithm between the two-stage moving blades and the frequency converter in the reconstructed DCS to respond to dynamic changes in boiler negative pressure.

[0109] The fusion module 230 is used to generate progressive interlocking protection commands based on the dynamic changes of boiler negative pressure, combined with the vibration spectrum, oil pressure gradient and actuator position feedback.

[0110] The balancing module 240 is used to execute protection commands, diagnose the operating status of both fans in real time, and achieve air volume balance under single fan failure through flue damper linkage and blade compensation.

[0111] The calibration module 250 is used to calibrate the blade-airflow control curve by simulating load disturbance scenarios in the unit maintenance window after achieving airflow balance.

[0112] The correction module 260 is used to determine the actual operating energy consumption data according to the control curve and dynamically correct the weights of the collaborative algorithm.

[0113] Figure 3 This is a schematic diagram of the structure of the electronic device provided in this embodiment.

[0114] like Figure 3 As shown, the electronic device may include: a processor 310, a communication interface 320, a memory 330, and a communication bus 340, wherein the processor 310, the communication interface 320, and the memory 330 communicate with each other through the communication bus 340. The processor 310 can call logic instructions in the memory 330 to execute the unit induced draft fan capacity expansion and modification control method. This method includes: expanding the DCS system hardware channels and deploying anti-interference communication links to adapt to the multi-source measurement and control requirements of the dual-stage adjustable blade induced draft fan, and completing hardware resource reconstruction; constructing a weighted adjustable collaborative algorithm for the dual-stage blades and frequency converter in the reconstructed DCS to respond to dynamic changes in boiler negative pressure; generating progressive interlocking protection instructions based on the dynamic changes in boiler negative pressure, combined with the fusion analysis of vibration spectrum, oil pressure gradient, and actuator position feedback; executing the protection instructions to diagnose the operating status of both fans in real time, and achieving air volume balance under single fan failure through flue damper linkage and blade compensation; after achieving air volume balance, simulating load disturbance scenarios in the unit maintenance window and calibrating the blade-air volume control curve; and determining the actual operating energy consumption data according to the control curve and dynamically correcting the weights of the collaborative algorithm.

[0115] Furthermore, the logical instructions in the aforementioned memory 330 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, 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 the present invention. 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.

[0116] On the other hand, the present invention also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the unit induced draft fan capacity expansion and modification control method provided by the above methods. The method includes: expanding the hardware channels of the DCS system and deploying an anti-interference communication link to adapt to the multi-source measurement and control requirements of the dual-stage adjustable blade induced draft fan and completing the hardware resource reconstruction; constructing a weighted adjustable collaborative algorithm of dual-stage blades and frequency converter in the reconstructed DCS to respond to the dynamic changes in boiler negative pressure; generating a progressive interlocking protection command based on the dynamic changes in boiler negative pressure, combined with the fusion analysis of vibration spectrum, oil pressure gradient and actuator position feedback; executing the protection command to diagnose the operating status of both fans in real time, and achieving air volume balance under single fan failure through flue damper linkage and blade compensation; after achieving air volume balance, simulating load disturbance scenarios in the unit maintenance window and calibrating the blade-air volume control curve; and determining the actual operating energy consumption data according to the control curve and dynamically correcting the weights of the collaborative algorithm.

[0117] On another front, the present invention also provides a non-transitory computer-readable storage medium storing a computer program thereon. When executed by a processor, this computer program implements the control method for capacity expansion and modification of the induced draft fan provided by the above methods. This method includes: expanding the hardware channels of the DCS system and deploying an anti-interference communication link to adapt to the multi-source measurement and control requirements of the dual-stage adjustable blade induced draft fan, and completing hardware resource reconfiguration; constructing a weighted adjustable collaborative algorithm for the dual-stage blade and frequency converter in the reconfigured DCS to respond to dynamic changes in boiler negative pressure; generating progressive interlocking protection commands based on the dynamic changes in boiler negative pressure, combined with the fusion analysis of vibration spectrum, oil pressure gradient, and actuator position feedback; executing the protection commands to diagnose the operating status of both fans in real time, and achieving airflow balance under single fan failure through flue damper linkage and blade compensation; after achieving airflow balance, simulating load disturbance scenarios in the unit maintenance window and calibrating the blade-airflow control curve; and determining the actual operating energy consumption data according to the control curve and dynamically correcting the weights of the collaborative algorithm.

[0118] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0119] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0120] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A control method for capacity expansion and retrofitting of a generator unit's induced draft fan, characterized in that, include: Expand the hardware channels of the DCS system and deploy anti-interference communication links to adapt to the multi-source measurement and control requirements of the dual-stage adjustable blade induced draft fan and complete the hardware resource reconstruction; In the reconstructed DCS, a weighted and adjustable collaborative algorithm for two-stage moving blades and frequency converters is constructed to respond to dynamic changes in boiler negative pressure. Based on the dynamic changes in the boiler negative pressure, combined with the fusion analysis of vibration spectrum, oil pressure gradient and actuator position feedback, a progressive interlocking protection command is generated. The protection command is executed to diagnose the operating status of both fans in real time, and to achieve air volume balance under single fan failure through the linkage of flue damper and blade compensation. After achieving air volume balance, simulate load disturbance scenarios in the unit maintenance window and calibrate the blade-air volume control curve. Based on the control curve, the actual operating energy consumption data is determined, and the weights of the collaborative algorithm are dynamically adjusted.

2. The control method for capacity expansion and modification of the induced draft fan of a generating unit according to claim 1, characterized in that, The deployment of the anti-interference communication link includes: Configure an independent shielded twisted-pair channel for the high-frequency vibration sensor; Install a signal isolation barrier on the DCS side to suppress electromagnetic interference; A dedicated data transmission channel for wind turbine control was established based on a fiber optic ring network. The independent shielded twisted-pair channel, the signal isolation barrier, and the dedicated data transmission channel form a complete anti-interference system.

3. The control method for capacity expansion and modification of the induced draft fan of a generating unit according to claim 1, characterized in that, The weight-adjustable collaborative algorithm includes: The dynamic response range of the boiler negative pressure change rate is divided into a high-speed response range and a low-speed response range; In the high-speed response range, blade angle adjustment is assigned as the main control weight, and in the low-speed response range, inverter adjustment is assigned as the main control weight.

4. The control method for capacity expansion and modification of the induced draft fan of a generating unit according to claim 3, characterized in that, The switching method for the master control weight is as follows: Real-time calculation of the deviation between the air volume setpoint and the actual output; The weighting coefficients of the moving blades and the frequency converter are dynamically adjusted based on the aforementioned deviation. When the deviation continues to increase and exceeds the threshold, the emergency adjustment mode of the moving blade angle is forcibly switched to complete the main control weight switch.

5. The control method for capacity expansion and modification of the induced draft fan of a generating unit according to claim 1, characterized in that, The fusion analysis includes: The vibration spectrum is decomposed using wavelet packet decomposition to extract characteristic frequency band energy; Based on the oil pressure gradient, a time series prediction model for the rate of change of the oil pressure gradient is established to predict oil pressure. When both the characteristic frequency band energy and the oil pressure prediction result exceed the limit, an intermediate response is triggered to generate a progressive interlocking protection command.

6. The control method for capacity expansion and modification of the induced draft fan of a generating unit according to claim 5, characterized in that, The generation of progressive interlocking protection commands includes: Generate primary, intermediate, and advanced responses; The primary response is to: increase the power of the lubricating oil station cooler and adjust the oil pressure setting value; The intermediate response is executed as follows: gradually reduce the blade opening of the abnormal wind to a safe level; The advanced response is executed as follows: the fan is tripped and the intercom damper is opened to release pressure.

7. The control method for capacity expansion and modification of the induced draft fan of a generating unit according to claim 6, characterized in that, Also includes: Collect stall critical state spectrum data during historical operation; Extract the amplitude-frequency correlation features from the spectrum data to form a unit-specific stall fingerprint database; The real-time spectrum is matched with the fingerprint database for similarity.

8. The control method for capacity expansion and modification of the induced draft fan of a generating unit according to claim 1, characterized in that, The method of achieving airflow balance under single fan failure through flue damper linkage and blade compensation includes: Calculate the theoretical airflow gap on the side of the faulty fan; Based on the dynamic gap value and the theoretical air volume gap, the upper limit of the operating fan blade opening is increased, and the opening of the connecting damper is adjusted simultaneously to balance the flue resistance and achieve air volume balance.

9. The control method for capacity expansion and modification of the induced draft fan of a generating unit according to any one of claims 1-8, characterized in that, The dynamic adjustment of the weights of the collaborative algorithm includes: Based on the control curve and historical operating energy consumption data, a three-dimensional relationship surface between blade angle, air volume, and power consumption is established. Based on the actual operating energy consumption data, the control points of the three-dimensional relational surface are iteratively updated, and the minimum slope of the surface is used as the optimization target of the weight coefficient to correct the weight of the collaborative algorithm.

10. A control system for upgrading and retrofitting a generator induced draft fan, characterized in that, include: The reconfiguration module is used to expand the hardware channels of the DCS system and deploy anti-interference communication links to adapt to the multi-source measurement and control requirements of the dual-stage adjustable blade induced draft fan and complete the hardware resource reconfiguration. The coordination module is used to build a weighted adjustable coordination algorithm between the two-stage moving blades and the frequency converter in the reconstructed DCS to respond to dynamic changes in boiler negative pressure. The fusion module is used to generate progressive interlocking protection commands based on the dynamic changes of the boiler negative pressure, combined with the fusion analysis of vibration spectrum, oil pressure gradient and actuator position feedback. The balancing module is used to execute the protection command, diagnose the operating status of both fans in real time, and achieve air volume balance under single fan failure through flue damper linkage and blade compensation. The calibration module is used to calibrate the blade-airflow control curve by simulating load disturbance scenarios in the unit maintenance window after achieving airflow balance. The correction module is used to determine the actual operating energy consumption data according to the control curve and dynamically correct the weights of the collaborative algorithm.

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