Methods, devices, storage media and electronic equipment for starting and stopping peak shaving of coal-fired power units

Abstract

This application discloses a method, apparatus, storage medium, and electronic equipment for starting and stopping peak shaving of a coal-fired power unit. The method includes: receiving a start / stop peak shaving command from the power grid; adjusting the unit load, main steam temperature, and reheat steam temperature according to the unit's operational stability requirements; controlling the turbine to trip and the generator interlock to trip, while maintaining boiler operation; adjusting the opening of the high and low pressure bypass valves according to the main and reheat steam pressure stability requirements; and when the turbine speed drops to a preset range, setting the turbine's start-up mode to bypass mode according to the turbine's standby operation requirements, and controlling the turbine to start up to the target speed. This application controls the turbine to trip and the generator to trip while maintaining boiler operation during disconnection, then adjusts the high and low pressure bypass valves to stabilize steam pressure, and finally starts up with bypass to stabilize turbine speed, reducing thermal stress and equipment wear, and improving the operational safety of the coal-fired power unit.

Description

Technical Field

[0001] This application relates to the field of power grid technology, and in particular to a method, apparatus, storage medium and electronic equipment for starting and stopping peak shaving of coal-fired power units. Background Technology

[0002] During power grid operation, with the increasing frequency of load fluctuations and the upgrading of dispatching requirements, coal-fired power units need to frequently respond to start-up and shutdown peak-shaving commands to ensure the balance of power grid supply and demand. Currently, coal-fired power units implement peak-shaving operations from a dispatching coordination perspective when responding to start-up and shutdown peak-shaving commands. This involves obtaining the current configuration information of the coal-fired power units, analyzing the energy consumption information during the start-up and shutdown process based on the configuration information, and determining whether the start-up and shutdown peak-shaving threshold has been reached, provided that the power demand of the power grid is met. When the threshold is met and the relevant constraints are verified, the output power of the pumped storage unit is connected to assist in peak-shaving, and then the start-up and shutdown peak-shaving command is issued. The start-up and shutdown peak-shaving operations of the units are then executed on-site according to the guidance of standardized operation cards.

[0003] However, during the equipment start-up and shutdown operations performed according to standardized operation cards, boilers and steam turbines need to be stopped and started multiple times to meet peak-shaving demands. In this repeated start-up and shutdown mode, core equipment such as boilers and steam turbines will frequently experience alternating temperature changes of heating and cooling. The thermal stress generated by the continuous and sudden temperature changes will accelerate the aging and corrosion of equipment components over a long period of time, and may even lead to cracks or deformation in critical components such as heated surfaces and shaft systems. This increases the probability of equipment failure during subsequent startups and directly affects the safe operation of the unit. Summary of the Invention

[0004] In view of the above problems, this application provides a method, apparatus, storage medium and electronic equipment for starting and stopping peak shaving of coal-fired power units.

[0005] To solve the above-mentioned technical problems, this application proposes the following solution:

[0006] In a first aspect, this application provides a method for starting and stopping peak shaving of a coal-fired power unit. The method includes: after receiving a start-up and stop peak shaving command from the power grid, adjusting the unit load, main steam temperature, and reheat steam temperature according to the unit's operational stability requirements; controlling the turbine to trip and interlocking the generator to trip, while maintaining the boiler's operation; adjusting the opening of the high and low pressure bypass valves according to the main and reheat steam pressure stability requirements; and when the turbine speed drops to a preset range, setting the turbine's start-up mode to bypass mode according to the turbine's standby operation requirements, and controlling the turbine to start up to the target speed.

[0007] Secondly, this application provides a coal-fired power unit start-up and shutdown peak-shaving device, which includes:

[0008] The first adjustment module is used to receive start-stop peak-shaving instructions from the power grid and adjust the unit load, main steam temperature and reheat steam temperature according to the unit's operational stability requirements.

[0009] The control module is used to control the turbine to trip and the generator to interlock trip, and to keep the boiler from shutting down;

[0010] The second adjustment module is used to adjust the opening of the high and low pressure bypass control valves according to the main reheat steam pressure stabilization requirements.

[0011] The control module is also used to set the turbine's start-up mode to bypass mode according to the turbine's standby operation requirements when the turbine speed drops to a preset range, and to control the turbine to start up to the target speed.

[0012] To achieve the above objectives, according to a third aspect of this application, a storage medium is provided, the storage medium including a stored program, wherein, when the program is executed, the device where the storage medium is located is controlled to perform the coal-fired power unit start-up and shutdown peak-shaving method of the first aspect.

[0013] To achieve the above objectives, according to a fourth aspect of this application, an electronic device is provided, the device including at least one processor, and at least one memory and bus connected to the processor; wherein the processor and memory communicate with each other through the bus; the processor is used to call program instructions in the memory to execute the coal-fired power unit start-up and shutdown peak-shaving method of the first aspect described above.

[0014] By employing the above-described technical solution, the technical solution provided in this application has at least the following advantages:

[0015] Upon receiving grid start-up and shutdown peak-shaving commands, this application first adjusts the unit load, main steam temperature, and reheat steam temperature according to the unit's operational stability requirements. This avoids sudden changes in core operating parameters due to command response, reducing thermal shock to critical components such as heating surfaces and turbines caused by abrupt parameter changes, and alleviating thermal stress accumulation. It controls the turbine to trip and the generator interlock to safely disconnect the unit from the grid while maintaining boiler operation. This avoids frequent heating and cooling processes during cold restarts, reducing the risk of component aging and corrosion due to alternating temperature changes. Furthermore, the boiler remains in hot standby mode without repeated preheating, avoiding equipment wear caused by repeated start-ups and shutdowns. The application adjusts the opening of high and low pressure bypass valves according to the main and reheat steam pressure stability requirements, preventing sudden pressure rises or falls caused by abrupt changes in the steam path after turbine tripping. This prevents overpressure damage to equipment and water circulation disruptions, further protecting boilers, steam pipelines, and other components. When the turbine speed drops to the preset range, it is restarted to the target speed using a bypass method to ensure stable speed during standby, avoid problems such as excessive equipment vibration caused by improper restarting, reduce equipment losses in the standby state of the unit, and at the same time ensure that the unit can quickly respond to subsequent grid connection commands, reduce the number of frequent start-ups and shutdowns, reduce the thermal stress of components caused by repeated temperature changes, and improve the operational safety of the unit.

[0016] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0017] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0018] Figure 1 A schematic flowchart of a coal-fired power unit start-up and shutdown peak-shaving method provided in an embodiment of this application is shown;

[0019] Figure 2 This paper shows a schematic diagram of the structure of a coal-fired power unit start-up and shutdown peak-shaving device provided in an embodiment of this application;

[0020] Figure 3 A schematic diagram of the structure of an electronic device provided in an embodiment of this application is shown. Detailed Implementation

[0021] Exemplary embodiments of the present application will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present application are shown in the drawings, it should be understood that the present application may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this application will be thorough and complete, and will fully convey the scope of the present application to those skilled in the art.

[0022] In the embodiments of this application, the terms "first," "second," etc., do not have a logical or temporal dependency, nor do they limit the quantity or execution order. It should also be understood that although the following description uses the terms "first," "second," etc., to describe various elements, these elements should not be limited by the terms. These terms are merely used to distinguish one element from another.

[0023] In this application, the term "at least one" means one or more, and the term "multiple" means two or more.

[0024] It should also be understood that the term “if” can be interpreted as “when” or “upon”, or “in response to determination” or “in response to detection”. Similarly, depending on the context, the phrase “if determination…” or “if detection [the stated condition or event]” can be interpreted as “when determination…” or “in response to determination…” or “when detection [the stated condition or event]” or “in response to detection [the stated condition or event]”.

[0025] This application provides a method for starting and stopping peak shaving of coal-fired power units. The method for starting and stopping peak shaving of coal-fired power units will be described in detail below with reference to the accompanying drawings. Figure 1 This application provides a flowchart illustrating a method for starting and stopping peak-shaving coal-fired power units. Specifically, it includes the following steps:

[0026] Step 110: After receiving the start-up and shutdown peak-shaving instructions from the power grid, adjust the unit load, main steam temperature and reheat steam temperature according to the unit's operational stability requirements.

[0027] When the control system of a coal-fired power unit receives a start / stop peak-shaving command from the power grid dispatch center, it first initiates the adjustment process of the unit's operating parameters. The core adjustments revolve around the unit load, main steam temperature, and reheat steam temperature to meet the requirements for stable operation. During this process, the control system gradually adjusts the unit's output load based on the unit's current operating status, ensuring that the rate of load change complies with equipment operating specifications and avoiding shocks to unit components due to sudden load changes.

[0028] In one specific implementation, when the coal-fired power unit control system receives a start / stop peak-shaving command from the power grid, it first performs a command parsing operation to extract the load adjustment direction (e.g., load reduction or load maintenance) and response time limit (e.g., requiring the load to be reduced from the current value to 30% of the rated load within 1 hour). These two parameters are the core basis for subsequent load adjustment planning and directly determine the overall rhythm and time nodes of load adjustment. Subsequently, the control system initiates the unit operation data acquisition process, collecting burner stability data on the boiler side, wall temperature distribution data of each area of ​​the heating surface, and turbine speed fluctuation data. The burner stability data is obtained through the boiler flame detection system, including flame intensity signals, flame pulsation frequency, and coal feed fluctuation feedback values ​​of each burner, used to determine whether the burner is in a stable combustion state. The wall temperature distribution data of each area of ​​the heating surface is collected by wall temperature sensors arranged in different areas of the heating surface such as the water-cooled wall, superheater, and reheater, forming a wall temperature distribution matrix along the height and width directions of each heating surface, which intuitively reflects the thermal uniformity of the heating surface. The turbine speed fluctuation data is collected in real time by the speed transmitter on the turbine shaft system, which records the fluctuation amplitude and frequency of the speed per unit time to evaluate the stability of the turbine operation.

[0029] Based on the collected burner stability data and wall temperature distribution data of various areas of the heated surface, the control system further analyzes the necessity and expected timing of the auxiliary steam header steam source switching and the plant power switching. For example, if the burner stability data shows insufficient flame intensity in some burners and localized low wall temperature distribution on the heated surface, it is determined that the current auxiliary steam header's onboard steam source cannot meet the steam demand of the auxiliary system. In this case, it is determined that the auxiliary steam header steam source switching needs to be performed, and the expected timing needs to be advanced to the initial stage of load adjustment (e.g., when the load drops to 80% of the rated load) to ensure the stability of subsequent burner air distribution and heated surface temperature control. If the heated surface wall temperature distribution is generally uniform, but the current power supply load of the plant power system is close to its upper limit, considering the potential increase in auxiliary equipment power demand during subsequent load adjustment, it is determined that the plant power switching needs to be performed, and the expected timing is set to when the load drops to 50% of the rated load to avoid instability in the plant power system due to power load fluctuations.

[0030] Meanwhile, during the load adjustment phase (before and after the switch between the auxiliary steam header and the plant power supply), the air preheater is put into continuous soot blowing operation: the continuous soot blowing mode is started through the air preheater soot blowing system to remove ash from the heated surface, ensure the heat exchange efficiency of the heated surface, avoid ash accumulation leading to local overheating or uneven heat exchange, and provide a basis for subsequent load and steam temperature stability adjustment.

[0031] After determining the response time limit and the expected sequence of the aforementioned switching operations, the control system divides the load adjustment process into stages. Taking a response time limit of 1 hour, an auxiliary steam switching sequence corresponding to 80% load, and a plant power switching sequence corresponding to 50% load as an example, the entire load adjustment process is divided into three stages. The first stage is the pre-processing stage, with a duration of 20 minutes, aiming to reduce the load from the current value to 80% of the rated load, while simultaneously completing the preparation work for the auxiliary steam header steam source switching. The second stage is the switching coordination stage, with a duration of 25 minutes, aiming to reduce the load from 80% to 50% of the rated load. During this stage, the auxiliary steam header steam source switching and plant power switching are performed simultaneously, ensuring load and steam temperature stability during the switching process. The third stage is the load reduction to the target range stage, with a duration of 15 minutes, aiming to reduce the load from 50% to below 30% of the rated load (i.e., the wet operating load range), preparing for the subsequent transition to wet operation. When the load further decreases to 10%~20% of the rated load, the control system sends a shutdown command to the coal mill to stop its operation and reduce the fuel supply to meet the low load operation requirements, thus avoiding coal quantity fluctuations or equipment wear caused by the low load operation of the coal mill.

[0032] Simultaneously, based on the collected turbine speed fluctuation data and wall temperature distribution data of each area of ​​the heated surface, the control system determines the load trigger point for the unit to switch to wet operation. For example, when the turbine speed fluctuation data shows that the speed fluctuation range exceeds ±50 rpm, or when the local wall temperature in each area of ​​the heated surface deviates from the design value by more than -30℃, combined with the unit's operating characteristic curve, it is determined that further load reduction at this time is likely to lead to water circulation instability. Therefore, the load trigger point is determined to be 30% of the rated load, and this trigger point is associated with the end of the third stage of load adjustment to ensure that when the load drops to 30% in the third stage, the wet operation switching operation can be initiated immediately.

[0033] Finally, based on the load adjustment direction (such as load reduction) and the wall temperature distribution data of each area of ​​the heated surface, the coordination logic between load adjustment and main steam temperature and reheat steam temperature adjustment at each stage is determined, forming a complete load adjustment strategy.

[0034] Specifically, based on the differences in wall temperature across different areas of the heated surface and the deviation of the wall temperature from the design tolerance value, the correlation between the load adjustment range and the main steam temperature adjustment range and the reheat steam temperature adjustment range for each stage is determined. For example, in the first stage (load decreases from the current value to 80%), if the wall temperature difference of the heated surface is 15℃ (less than the preset threshold of 20℃) and the deviation of the wall temperature from the design tolerance value is -10℃, the load adjustment range for this stage is determined to be a 5% reduction in rated load each time, the main steam temperature adjustment range is a 3℃ reduction each time, and the reheat steam temperature adjustment range is a 2℃ reduction each time, ensuring that the load and steam temperature adjustments are synchronized and do not exacerbate the wall temperature deviation. If in the second stage (load decreases from 80% to 50%), the wall temperature difference of the heated surface increases to 18℃ and the deviation of the wall temperature from the design tolerance value is -15℃, then the load adjustment range is reduced to a 3% reduction in rated load each time, the main steam temperature adjustment range is maintained at 3℃, and the reheat steam temperature adjustment range is increased to 3℃. By slowing down the rate of load decrease and increasing the intensity of reheat steam temperature adjustment, the wall temperature distribution of the heated surface is balanced.

[0035] Based on the anticipated timing of the auxiliary steam header steam source switching and the plant power switching, and according to the changes in the unit's thermal state before and after the switching, the control system further adjusts the adjustment rates of the main steam temperature and reheat steam temperature at each stage. For example, 10 minutes before the auxiliary steam header steam source switching in the second stage, the main steam temperature adjustment rate is reduced from 3℃ / 10 minutes to 2℃ / 10 minutes, and the reheat steam temperature adjustment rate is reduced from 3℃ / 10 minutes to 2.5℃ / 10 minutes to avoid sudden changes in steam temperature caused by steam source fluctuations during the switching process. Five minutes after the switching is completed, once the unit's thermal state has stabilized, the adjustment rates of the main steam temperature and reheat steam temperature are restored to their original set values ​​to ensure efficient steam temperature adjustment.

[0036] Finally, by integrating the aforementioned correlation between load and steam temperature adjustment ranges and steam temperature adjustment rates, the initiation and execution sequence of load adjustment, main steam temperature adjustment, and reheat steam temperature adjustment at each stage is determined. For example, in the first stage, each adjustment operation follows the sequence: first, initiate main steam temperature adjustment; 3 minutes later, initiate reheat steam temperature adjustment; 5 minutes later, initiate load adjustment, ensuring that steam temperature adapts to load changes in advance. During the second stage switching operation, the sequence follows: first, pause load adjustment; then, initiate the switching operation; after the switching is completed, first, restore steam temperature adjustment to the target value; then, initiate load adjustment, avoiding system instability caused by the overlap of switching and load / steam temperature adjustments. Through the above sequence settings, a load adjustment strategy is formed that includes the coordination path of load, main steam temperature, and reheat steam temperature at each stage. This strategy can be directly used to guide subsequent load and steam temperature adjustment operations of the unit, ensuring that the entire process meets the unit's operational stability requirements.

[0037] While the coal-fired power unit control system adjusts the output load based on the unit's current operating status, it simultaneously initiates a refined adjustment process for the main steam temperature and reheat steam temperature to ensure dynamic adaptation of steam temperature to load changes and maintain the stability of the unit's thermal system. Specifically, the control system achieves steam temperature regulation by coordinating the adjustment of boiler combustion parameters and desuperheating water flow. Based on previously collected burner stability data and wall temperature distribution data for each area of ​​the heating surface, the system dynamically adjusts the coal feed rate and air distribution method of the operating burners. If the wall temperature of a certain area of ​​the heating surface is too low and the main steam temperature does not meet the adjustment expectations, the coal feed rate of the corresponding burner in that area is increased and the secondary air supply is optimized to enhance local combustion intensity and increase steam temperature. If the wall temperature of the heating surface is close to the deviation range of the design tolerance value, the combustion load of the corresponding burner is appropriately reduced to avoid equipment risks caused by excessively high steam temperature. To adjust the desuperheating water flow rate, desuperheating water flow sensors installed on the main steam and reheat steam pipelines collect real-time data on the actual flow rate of the desuperheating water. This data, combined with the steam temperature deviation, dynamically adjusts the opening of the desuperheating water regulating valve. For example, when the main steam temperature is higher than the set value, the opening of the desuperheating water regulating valve is increased to boost the desuperheating water flow rate and quickly reduce the steam temperature; conversely, the opening is decreased when the temperature is lower. Simultaneously, the control system sets preset stabilization rates for the main steam temperature and reheat steam temperature based on the phases of load adjustment. These rates are constrained by the thermal stress tolerance range of the heated surfaces and determined in conjunction with the load adjustment amplitude. For instance, during the rapid load adjustment phase, the steam temperature adjustment rate is controlled at 10~20℃ / h, while during the stable transition phase, it is adjusted to 5~10℃ / h to ensure gradual steam temperature changes and prevent thermal stress damage caused by sudden temperature changes on the heated surfaces due to excessively rapid rates. Throughout the adjustment process, the control system analyzes the main steam temperature and reheat steam temperature data collected every minute in conjunction with the current load data. If it finds that the steam temperature and load mismatch exceeds the preset range (e.g., the load decreases by 10% but the steam temperature only decreases by 5°C), it immediately fine-tunes the combustion parameters or the desuperheating water flow rate until the steam temperature adjustment and load change are coordinated and matched, thus maintaining the stable operation of the unit's thermal system.

[0038] In addition, when the coal-fired power unit performs load adjustment according to the above-mentioned load adjustment strategy, and the unit load is confirmed in real time by the load transmitter to have dropped to the previously determined load trigger point for the unit to switch to wet operation, the feedwater flow stabilization control operation is initiated first. At this time, the unit's feedwater control system will immediately lock the current feedwater flow value, collect the actual flow data in the feedwater pipeline in real time through the feedwater flow transmitter, and compare this data with the locked value. If there is a fluctuation within ±5%, the control system will compensate by adjusting the speed of the feedwater pump or the opening of the feedwater regulating valve to ensure that the feedwater flow is always maintained at the stable value corresponding to the load trigger point, avoiding the disruption of water circulation on the boiler heating surface due to sudden changes in feedwater flow. The core purpose of this step is to provide a stable water circulation foundation for the subsequent switch to wet operation, preventing the heating surface from dry burning due to insufficient feedwater during the load reduction process, or the steam carrying water exceeding the standard due to excessive feedwater.

[0039] While maintaining a constant water flow rate, the control system begins to adjust the coal feed rate based on the unit's current operating data to achieve a smooth transition of the unit to wet operation. The core basis for adjusting the coal feed rate includes three aspects: First, the current burner stability data of the boiler obtained through the boiler flame detection system, such as the flame intensity signal of each burner, the flame pulsation frequency, and the feedback value of coal feed rate fluctuation. If it is detected that the flame intensity of some burners is close to the lower limit threshold of stable combustion, the rate of coal feed rate reduction needs to be slowed down to avoid burner shutdown. Second, the wall temperature distribution data of each area of ​​the heating surface collected by wall temperature sensors arranged in different areas of the boiler water-cooled wall, superheater, etc. If the wall temperature distribution shows that the wall temperature in a local area is more than 10°C lower than the design value, the reduction of coal feed rate needs to be appropriately controlled to prevent the wall temperature from dropping further and causing uneven thermal stress on the heating surface. Third, the load adjustment requirements of wet operation. In view of the current low load state below 30%, wet operation needs to ensure that the steam has a certain humidity to maintain water circulation. Therefore, the coal feed rate adjustment should aim to achieve a steam humidity of 10%-15% (detected by a steam humidity meter). In specific operation, the control system gradually reduces the speed of each coal feeder through the coal feeder speed controller. Each adjustment is controlled within the range of 5%-10% of the rated speed, and the adjustment interval is set to 2-3 minutes. Every minute, the steam humidity and steam pressure data are collected through the steam parameter monitoring system until the steam humidity stabilizes in the range of 10%-15%. At this time, it is confirmed that the unit has successfully switched to wet operation, and further adjustment of the coal feed rate is stopped.

[0040] During the transition of the unit to wet operation, the feedwater pathway switching operation is initiated simultaneously. Before switching, the control system first confirms the current status of the main feedwater valve and the bypass regulating valve (main valve fully open, bypass regulating valve fully closed) through the valve status monitor, and detects whether the pressure in the feedwater pipeline is stable at the pressure value corresponding to the current load (e.g., 3.5-4.0 MPa) through the pressure sensor. During switching, the principle of opening before closing is followed. First, the bypass regulating valve is slowly opened through the bypass regulating valve controller, with the opening rate set to increase by 10% every 10 seconds. At the same time, the flow rate of the bypass regulating valve is monitored through the flow transmitter. When the bypass regulating valve opening reaches 80% and the flow rate is basically consistent with the current flow rate of the main valve, the main feedwater valve is slowly closed, with the closing rate consistent with the opening rate, until the main valve is completely closed. Then, the opening of the bypass regulating valve is finely adjusted to a value that matches the current feedwater flow requirement (usually 50%-60% opening). After the switchover is complete, the control system will continuously monitor and fine-tune the feedwater flow rate through the bypass regulating valve to ensure that the feedwater flow rate matches the low-load water circulation requirements under wet operation. The key to this step is to avoid feedwater interruption or pipeline overpressure during the switchover process. At the same time, the fine adjustment capability of the bypass regulating valve adapts to the low-flow feedwater control requirements under low load during wet operation, ensuring that the boiler water-cooled walls and other heating surfaces are always in a stable water circulation state.

[0041] Throughout the process, the water circulation status is continuously monitored through the boiler water circulation monitoring system (such as water-cooled wall outlet temperature monitoring and downcomer flow monitoring). If the water-cooled wall outlet temperature deviation exceeds 15℃ or the downcomer flow fluctuation exceeds ±10%, the coal feed adjustment or water supply path switching operation must be immediately suspended. The operation can only continue after the parameters have stabilized, ensuring the safety and stability of the entire process of the unit switching to wet operation.

[0042] Step 120: Control the turbine to trip and the generator interlock to trip, while keeping the boiler running.

[0043] After the unit load is adjusted to the preset disconnection preparation range, the control system executes the turbine tripping operation, which triggers the turbine's emergency shutdown mechanism to achieve the tripping action. At the same time, according to the preset interlocking logic, the generator synchronously completes the interlocking tripping, thereby realizing the disconnection of the unit from the grid.

[0044] Specifically, the control system first sends a trip command to the turbine's emergency shutdown system, which triggers the turbine's emergency shutdown valve to cut off the steam passage to the turbine, causing the turbine rotor to lose its power source and begin to decelerate. At the same time, the control system sends a trip command to the generator's output circuit breaker according to the preset interlocking logic, which disconnects the generator from the grid bus and completes the disconnection of the unit from the grid.

[0045] After the turbine trips and the generator interlock trips, the core task is to keep the boiler running. To maintain this, a preset number of burners are first determined and kept running based on the current burner stability data. At this time, the control system collects real-time combustion status data for each burner through the boiler flame detection system. This data specifically includes the flame intensity signal, flame pulsation frequency, and feedback on the matching degree between coal feed and flame intensity for each burner. If the flame intensity signal of a burner is detected to be below a preset threshold, the flame pulsation frequency exceeds the stable range of 5-15Hz, or there is a significant mismatch between the coal feed and flame intensity (e.g., the coal feed increases but the flame intensity does not increase synchronously), then the burner is deemed to have insufficient stability and must be shut down. Conversely, burners with stable flame intensity, normal pulsation frequency, and matching coal feed are kept running. The number of burners kept running must ensure sufficient heat load in the furnace to support stable boiler water circulation, and is usually determined based on the boiler's rated evaporation capacity. For example, for a 300MW boiler, retaining 2-3 burners is sufficient to meet the non-shutdown requirement, and the retained burners should be evenly distributed around the furnace to avoid local overheating or excessively low temperature in the furnace.

[0046] While maintaining the continuous operation of a preset number of burners, the control system further adjusts the burner air distribution ratio to maintain the boiler furnace temperature within a preset stable range, ensuring the boiler remains uninterrupted for extended periods and the safety of the heating surfaces. The air distribution ratio adjustment is based on three aspects: First, the aforementioned real-time collected boiler burner stability data. If the flame intensity of a retained burner shows a decreasing trend (e.g., the signal value drops from the normal 80% to 70%), the primary air ratio corresponding to that burner needs to be appropriately increased (primary air mainly carries pulverized coal into the furnace; increasing primary air can improve pulverized coal conveying efficiency and enhance flame intensity). If the flame pulsation intensifies (frequency exceeding 15Hz), the primary air ratio needs to be reduced and the secondary air ratio appropriately increased (secondary air mainly provides combustion air to optimize combustion conditions). Second, the wall temperature distribution data of each area of ​​the heating surface. This data is collected by wall temperature sensors placed in different areas of the boiler's water-cooled walls, superheaters, reheaters, etc., forming a wall temperature distribution map of each heating surface. If the map shows that the wall temperature of one side of the furnace heating surface is significantly higher than the other side (e.g., the temperature difference exceeds 30℃), then the air distribution ratio is adjusted. The system adjusts the secondary air opening of the burners on the low-temperature side to increase the secondary air supply to enhance the heat load in that area, while reducing the secondary air supply to the high-temperature side to suppress the heat load and balance the wall temperature of the heated surfaces. Thirdly, it maintains the boiler furnace temperature within a preset stable range. The furnace temperature is monitored in real time by thermocouple sensors arranged within the furnace. The preset stable range is usually determined based on the characteristics of the boiler fuel (such as the ignition temperature and burnout temperature of the coal). For example, for bituminous coal, the preset furnace temperature range is 800-900℃. If the furnace temperature is detected to be below 800℃, the overall ratio of primary and secondary air volume in each retained burner is increased (while ensuring a reasonable excess air coefficient, increasing combustion intensity to raise the furnace temperature). If the temperature is above 900℃, the overall air volume ratio is appropriately reduced or the coal feed is slightly adjusted to avoid excessively high furnace temperatures leading to overheating of the heated surfaces. During the specific air distribution adjustment process, the control system continuously fine-tunes the opening of the primary air damper and secondary air damper of each burner through the damper actuator. Each adjustment range is controlled within 5%-10% of the maximum damper opening, and the adjustment interval is set to 1-2 minutes. Every 30 seconds, the flame intensity, heating surface wall temperature and furnace temperature data are collected. Based on the data feedback, the air distribution ratio is continuously optimized until the furnace temperature stabilizes within the preset range, and the burner flame is stable and the heating surface wall temperature is uniformly distributed. At this time, the boiler enters a stable operating state that does not shut down for a long time.

[0047] Step 130: Adjust the opening of the high and low pressure bypass control valves according to the main reheat steam pressure stabilization requirements.

[0048] After the turbine trips, the pressure in the main reheat steam system will fluctuate due to the sudden change in the steam output path. At this time, the opening of the high and low pressure bypass valves needs to be adjusted promptly according to the main reheat steam pressure stabilization requirements. At the moment of tripping, the control system rapidly opens the high and low pressure bypass valves to a preset initial opening and maintains this opening for a preset duration. This quickly buffers the pressure surge caused by the tripping action, preventing damage to the boiler and steam pipelines from a sudden pressure increase. Once the pressure fluctuations subside, the high and low pressure bypass valves switch to automatic adjustment mode. The control system collects the actual pressure data of the main reheat steam in real time and compares it with the preset pressure control target. Based on the difference, it dynamically adjusts the valve opening to ensure the main reheat steam pressure remains stable within the set range, guaranteeing the safe operation of the boiler without shutting down.

[0049] Before activating the high and low pressure bypass valve control, the control system first increases the condensate pressure setpoint: the condensate pressure is set to the current main reheat steam pressure control target value +2MPa to ensure that the bypass system desuperheating water has sufficient pressure, and to avoid steam temperature runaway during valve adjustment due to insufficient desuperheating water pressure, thus providing a guarantee for the stable adjustment of the bypass valve in the future.

[0050] Specifically, the moment the turbine receives the tripping command and begins the tripping operation, the initial opening control of the high-pressure and low-pressure bypass valves must be initiated immediately. First, the bypass valve control system simultaneously sends opening commands to both the high-pressure and low-pressure bypass valves, adjusting their initial openings to 3-5% (the specific opening is determined based on the unit's rated capacity; for example, 3% for a 300MW unit and 5% for a 600MW unit). Simultaneously, opening commands are sent to the high-pressure and low-pressure bypass desuperheating water electric valves, ensuring they are fully open within 10 seconds of valve opening. This allows desuperheating water to enter the bypass system promptly, preventing high-temperature steam from directly impacting the pipelines and damaging equipment when the valves open. After completing the initial opening and desuperheating water electric valve operation, maintain this initial opening for a preset time (usually set to 1-2 minutes, the specific duration determined based on the pressure fluctuation curve after previous unit trips, ensuring coverage of the peak pressure surge). The core purpose of this operation is to buffer the main reheat steam pressure surge caused by the sudden change in the steam output path after turbine tripping. Because the steam that was originally entering the turbine to perform work suddenly loses its discharge channel after turbine tripping, the pressure in the main reheat steam system can easily surge rapidly within 10-30 seconds. An initial opening of 3-5% can quickly establish a steam bypass channel, directing excess steam into the condenser, thereby suppressing the pressure surge and preventing the pressure from exceeding the rated withstand pressure of the pipelines or equipment. During this period, pressure data is collected in real time through the main reheat steam pressure transmitter, and the pressure value is recorded every 2 seconds. If the pressure peak does not exceed 120% of the control target value, the initial opening and maintenance time settings are considered reasonable. If the pressure peak exceeds the target value, the initial opening is appropriately increased (e.g., by 0.5~1%) or the maintenance time is extended (e.g., by 30 seconds) in the next operation to ensure the pressure buffering effect.

[0051] After the main reheat steam pressure has passed the initial opening buffer, the pressure fluctuation amplitude will gradually decrease (usually, when the pressure change rate drops to within ±0.1 MPa / min, the pressure fluctuation is considered to be relatively flat). At this point, the system switches to a mode that adjusts the opening of the high and low pressure bypass valves based on the difference between the actual main reheat steam pressure and the control target. First, the actual pressure data is continuously collected by the main reheat steam pressure transmitter. Every second, the actual pressure value is compared with the previously determined control target value, and the difference between the two is calculated. For example, if the actual pressure is 7.5 MPa and the control target is 7 MPa, the difference is +0.5 MPa; if the actual pressure is 6.3 MPa and the control target is 7 MPa, the difference is -0.7 MPa. Subsequently, the bypass valve control system outputs corresponding opening adjustment commands based on the sign and absolute value of the difference: If the difference is positive (actual pressure is higher than the control target), it indicates insufficient steam discharge, and the valve opening is increased. The adjustment range is proportional to the absolute value of the difference. For example, when the difference is within 0.5 MPa, the valve opening is increased by 1-2% each time; when the difference is 0.5-1 MPa, the valve opening is increased by 2-3% each time, with an adjustment interval of 30 seconds to avoid sudden pressure drops caused by abrupt changes in opening. If the difference is negative (actual pressure is lower than the control target), it indicates excessive steam discharge, and the valve opening is decreased. The adjustment logic is the same as when the difference is positive. For example, when the difference is within -0.5 MPa, the valve opening is decreased by 1-2% each time; when the difference is -0.5 to -1 MPa, the valve opening is decreased by 2-3% each time. Simultaneously, during the adjustment of the regulating valve opening, the flow rate and temperature of the high and low bypass desuperheating water are continuously monitored. By adjusting the opening of the desuperheating water regulating valve, the flow rate of the desuperheating water is ensured to match the valve opening (e.g., when the valve opening is 5%, the desuperheating water flow rate is controlled at 50 t / h; when the valve opening is 8%, the desuperheating water flow rate is controlled at 80 t / h). This ensures that the temperature of the steam passing through the bypass is reduced to a range that the condenser can withstand (e.g., below 200℃), preventing high-temperature steam from damaging the condenser. Through the above dynamic adjustments, the main reheat steam pressure is ultimately stabilized within ±0.2 MPa of the control target value, achieving stable control of the main reheat steam pressure.

[0052] Step 140: When the turbine speed drops to the preset range, set the turbine's start-up mode to bypass mode according to the turbine's standby operation requirements, and control the turbine to start up to the target speed.

[0053] After the turbine is tripped, its speed gradually decreases, and the control system continuously monitors the turbine's speed data in real time. When the speed drops to the preset start-up preparation range, the control system switches the turbine's start-up mode to bypass mode according to the technical requirements of the turbine's standby operation. This mode can provide stable steam parameter support for the start-up process through the coordinated adjustment of the high and low pressure bypass systems. Subsequently, the control system initiates the start-up control process, controlling the turbine's start-up rate by adjusting the steam flow and pressure entering the turbine, ensuring a smooth start-up process, and avoiding problems such as excessive speed fluctuations and excessive vibration. Ultimately, the turbine speed is stabilized at the target speed, putting the turbine in a stable standby state so that it can quickly respond to grid connection commands when needed by the power grid.

[0054] Specifically, during the start-up process, if the deviation between the heating surface wall temperature and the design tolerance value is determined to be within a preset warning range based on the heating surface wall temperature distribution data (e.g., the design tolerance value is 480℃, and the preset warning range is 460~480℃, i.e., deviation ≤20℃), or if the burner stability is determined to have decreased based on the burner stability data (e.g., the flame intensity signal value drops from 80% to 65%, or the flame pulsation frequency exceeds the 5~15Hz range to 18Hz), the control system immediately initiates a start-up rate reduction operation. First, it retrieves the current boiler burner stability data and the wall temperature distribution data for each area of ​​the heating surface, and combines this with the turbine's standby operation requirements (the target speed is 3000rpm, which needs to be gradually approached while ensuring safety) to determine the rate reduction magnitude. For example, if the flame intensity of only a single burner drops to 68% (close to the lower limit of stability, 65%), and the maximum deviation of the heating surface wall temperature is 15°C (within the warning range), the start-up rate should be reduced from the initial 50 rpm / min to 30 rpm / min. If the flame intensity of both burners drops to 65%, and the wall temperature deviation in two superheater areas reaches 18°C, the start-up rate should be further reduced to 15 rpm / min to avoid increased steam demand due to excessively rapid start-up, which could exacerbate burner instability or the risk of overheating of the heating surface. After adjustment, the above parameters should be monitored every 30 seconds. If burner stability recovers (flame intensity rises back to above 70%) and the wall temperature deviation of the heating surface decreases to below the lower limit of the warning range, the start-up rate can be gradually restored to 70%~80% of the initial value to ensure that the start-up progress is not excessively affected.

[0055] If, during the start-up process, the monitoring of the main reheat steam pressure trend indicates that the difference between the actual main reheat steam pressure and the control target exceeds the preset allowable range (e.g., the allowable range is ±0.3 MPa, and the actual pressure reaches 7.4 MPa or 6.6 MPa), the control system prioritizes bringing the main reheat steam pressure back to the control target and adjusts the opening of the high-pressure and low-pressure bypass valves based on this difference. For example, if the actual pressure is 7.4 MPa (difference +0.4 MPa, exceeding the allowable range), the opening of the high-pressure bypass valve is increased from the current 10% to 12%, and the opening of the low-pressure bypass valve is increased from 8% to 10%, thereby reducing the system pressure by increasing steam discharge. If the actual pressure is 6.6 MPa (difference -0.4 MPa), the opening of the high-pressure bypass valve is decreased from 10% to 8%, and the opening of the low-pressure bypass valve is decreased from 8% to 6%, thereby increasing the system pressure by reducing steam discharge. After correction, the main reheat steam pressure is continuously monitored until it stabilizes within ±0.2 MPa of the control target (determined as pressure stability). Subsequently, based on the wall temperature distribution data of each area of ​​the heating surface after pressure stabilization (e.g., whether the wall temperature is still within the safe range), the current burner stability data of the boiler (e.g., whether the flame has returned to stability), and the turbine's standby operation requirements (e.g., the difference between the current speed and the target speed of 3000 rpm), the start-up rate is adjusted accordingly. For example, if the burner flame intensity recovers to 75% after pressure stabilization, the wall temperature deviation of the heating surface decreases to 10°C, and the current speed is 2500 rpm (a difference of 500 rpm from the target speed), then the start-up rate is set to 40 rpm / min, ensuring start-up efficiency while avoiding further parameter fluctuations.

[0056] Throughout the start-up process, the start-up rate and bypass valve opening are continuously and collaboratively controlled: every minute, based on the latest collected data on speed fluctuations, burner stability, main reheat steam pressure, and heating surface wall temperature, both are finely adjusted to ensure that the start-up rate and steam parameters are always matched. When the turbine speed reaches the preset target speed (3000 rpm) as monitored by the speed transmitter, and the speed fluctuation is ≤ ±10 rpm (determined as stable speed), while the main reheat steam pressure is stable within the control target range of ±0.2 MPa, the burner continues to operate stably, and there is no risk of overheating of the heating surface wall temperature, the start-up rate adjustment is stopped, the current bypass valve opening and burner operating status are maintained, and the turbine is stabilized at the target speed of 3000 rpm, entering standby mode to prepare for grid connection operations when the grid demands it.

[0057] After the turbine stabilizes at the target speed and enters standby mode, various operating parameters need to be continuously monitored during start-up, shutdown, and peak shaving. Once a parameter exceeds the protection limit, the control system will immediately issue an alarm signal, specifically including: the wall temperature of each stage of heating surface is lower than the design value; the liquid level of the condenser and deaerator becomes unstable; the vacuum is lower than the lower limit or higher than the upper limit; the vibration value of each bearing of the unit exceeds the alarm value; the temperature of each bearing of the unit exceeds the alarm value and the rate of temperature rise of the bearing exceeds the limit value; the superheated or reheated steam temperature is out of control or the steam temperature drops by more than 50°C within 10 minutes; the temperature difference between the superheated or reheated temperature and the cylinder temperature is greater than 50°C; the temperature difference between the upper and lower walls of the high-pressure inner cylinder increases by more than 42°C; the temperature difference between the upper and lower walls of the intermediate and high-pressure outer cylinder increases by more than 56°C; the negative expansion difference of the cylinder is less than -1.8mm; the axial displacement increases by more than ±1.0mm; the high-pressure exhaust temperature is too high; the high-pressure exhaust pressure ratio is less than or equal to 1.7; and the liquid level in the storage tank exceeds 20m and shows no signs of falling for more than 30 seconds.

[0058] When a grid connection command is received, the generator is first checked to see if it meets the grid connection conditions. Specifically, this includes the turbine speed being stable at the target speed (3000 rpm), the generator output voltage matching the grid voltage, the frequency being consistent, and the phase being synchronized. After confirming that the grid connection conditions are met, an application is made to the grid dispatch for grid connection. Once the dispatch permits, a routine grid connection operation ticket is executed to complete the unit grid connection operation and realize the closed-loop process of start-up, shutdown, and peak shaving.

[0059] In summary, this application prioritizes adjusting the unit load, main steam temperature, and reheat steam temperature after receiving grid start-up and shutdown peak-shaving commands. This avoids sudden changes in the core operating parameters of the unit due to command response, and solves the problem of impact and operational fluctuations caused by sudden parameter changes on key components such as the unit's heating surface and turbine.

[0060] By controlling the turbine tripping, the turbine can be stopped from working, and the generator interlock tripping can directly disconnect the electrical connection between the unit and the grid. The two work together to achieve physical isolation between the unit and the grid, avoiding the impact of current and torque fluctuations on the grid and unit components during the disconnection process, thus ensuring safe disconnection. At the same time, keeping the boiler running means that the boiler always maintains a certain combustion intensity and thermal state, without having to go through the long heating, pressurization, and fuel preheating process of cold restart, which significantly reduces the fuel consumption and time cost required for restart. During peak shaving, the unit needs to be temporarily shut down to adapt to the grid load demand, and it also needs to be quickly connected to the grid for power generation when the grid needs it. This shutdown without shutting down the boiler not only meets the peak shaving shutdown requirements, but also puts the boiler in a hot standby state. Subsequently, the turbine can be quickly started to complete the start-up and grid connection, thus resolving the contradiction between unit shutdown and rapid response to grid connection requirements.

[0061] After the turbine trips, the main reheat steam that was originally going to the turbine to perform work suddenly loses its normal output path, which can easily lead to a sudden increase in system pressure due to steam retention, or a sudden drop in pressure due to the lack of proper steam drainage. This application adjusts the opening of the high and low pressure bypass valves according to the main reheat steam pressure stabilization requirements, and can flexibly control the steam discharge through the bypass channel. This stable pressure environment can prevent overpressure damage caused by excessive pressure exceeding the rated tolerance of the boiler and steam pipelines, and can also prevent excessively low pressure from disrupting the balance of the water circulation in the boiler and causing turbulence, ultimately solving the equipment risks caused by abnormal pressure.

[0062] By using a bypass method to rev up to the target speed when the turbine speed drops to the preset range, the turbine speed stability during standby is ensured, avoiding problems such as speed fluctuations and excessive equipment vibration caused by improper revving methods. This solves the problem of the unit's inability to quickly adapt to subsequent grid connection commands in standby mode, and ultimately enables coal-fired power units to safely, stably and efficiently cooperate with grid dispatching needs during start-up, shutdown and peak shaving.

[0063] It is understood that, in order to achieve the functions in the above embodiments, the computer device includes hardware structures and / or software modules corresponding to the execution of each function. Those skilled in the art should readily recognize that, based on the units and method steps described in conjunction with the embodiments disclosed in this application, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed by hardware or by computer software driving hardware depends on the specific application scenario and design constraints of the technical solution.

[0064] Furthermore, as a response to the above Figure 2 The implementation of the method embodiment shown in this application provides a coal-fired power unit start-up and shutdown peak-shaving device. The embodiment of this device corresponds to the aforementioned method embodiment. For ease of reading, this embodiment will not repeat the details of the aforementioned method embodiment, but it should be understood that the device in this embodiment can correspondingly implement all the contents of the aforementioned method embodiment. Specifically, as shown... Figure 2 As shown, the coal-fired power unit start-up and shutdown peak-shaving device 200 includes:

[0065] The first adjustment module 210 is used to receive start-stop peak-shaving instructions from the power grid and adjust the unit load, main steam temperature and reheat steam temperature according to the unit's operational stability requirements.

[0066] The control module 220 is used to control the turbine to trip and the generator to interlock trip, and to keep the boiler from shutting down;

[0067] The second adjustment module 230 is used to adjust the opening of the high and low pressure bypass control valves according to the main reheat steam pressure stabilization requirements.

[0068] The control module 240 is also used to set the turbine's start-up mode to bypass mode according to the turbine's standby operation requirements when the turbine speed drops to a preset range, and to control the turbine to start up to the target speed.

[0069] Furthermore, such as Figure 2 As shown, the first adjustment module 210 is specifically used to extract the load adjustment direction and response time limit from the start-up and shutdown peak shaving command; collect the current boiler burner stability data, wall temperature distribution data of each area of ​​the heating surface, and turbine speed fluctuation data; determine the necessity and expected timing of the auxiliary steam header steam source switching and plant power switching based on the burner stability data and wall temperature distribution data of each area of ​​the heating surface; divide the load adjustment into stages based on the response time limit and expected timing; determine the load trigger node for the unit to switch to wet operation based on the turbine speed fluctuation data and wall temperature distribution data of each area of ​​the heating surface, and associate the load trigger node with the corresponding load adjustment stage; determine the coordination logic between load adjustment and main steam temperature and reheat steam temperature adjustment in each stage based on the load adjustment direction and wall temperature distribution data of each area of ​​the heating surface, and form a load adjustment strategy.

[0070] Furthermore, such as Figure 2 As shown, the first adjustment module 210 is specifically used to determine the correlation between the load adjustment range and the main steam temperature adjustment range and the reheat steam temperature adjustment range at each stage based on the wall temperature differences in each area of ​​the heated surface and the deviation of the wall temperature from the design tolerance value; combined with the expected timing of the auxiliary steam header steam source switching and plant power switching, and based on the changes in the unit's thermal state before and after the switching, adjust the adjustment rate of the main steam temperature and reheat steam temperature at each stage; integrate the correlation and rate adjustment to determine the start and execution sequence of the load adjustment and the main steam temperature adjustment and reheat steam temperature adjustment at each stage, forming a load adjustment strategy that includes the coordination path of the load at each stage and the main steam temperature and reheat steam temperature.

[0071] Furthermore, such as Figure 2 As shown, the first adjustment module 210 is also used to maintain the feedwater flow rate unchanged when the unit load is adjusted to the load trigger node; reduce the coal feed rate according to the current burner stability data, wall temperature distribution data of each area of ​​the heating surface, and load adjustment requirements of wet operation, so that the unit switches to wet operation; and switch the feedwater passage from the main valve to the bypass regulating valve to adapt to the feedwater control requirements under wet operation.

[0072] Furthermore, such as Figure 2As shown, the control module 220 is specifically used to control the turbine to trip and cause the generator interlock to trip, and then, based on the current burner stability data of the boiler, retain a preset number of burners to continue operating; based on the current burner stability data of the boiler, the wall temperature distribution data of each area of ​​the heating surface, and the requirement to maintain the boiler furnace temperature within a preset stable range, the control module adjusts the burner air distribution ratio to maintain the boiler furnace temperature within a preset stable range, so as to ensure that the boiler does not shut down.

[0073] Furthermore, such as Figure 2 As shown, the second adjustment module 230 is specifically used to determine the control target of the main reheat steam pressure based on the current burner operation status and coal feed fluctuation of the boiler; at the moment of turbine tripping, the high and low pressure bypass valves are opened to the preset initial opening degree and maintained for a preset duration to buffer the main reheat steam pressure fluctuation caused by tripping; after the pressure fluctuation tends to level off, the opening degree of the high and low pressure bypass valves is adjusted according to the difference between the actual pressure of the main reheat steam and the control target.

[0074] Furthermore, such as Figure 2 As shown, the control module 240 is specifically used to monitor turbine speed fluctuation data, current boiler burner stability data, and main reheat steam pressure change trends after starting the turbine in bypass mode. If the deviation between the heating surface wall temperature and the design tolerance value is within a preset warning range, or if the boiler's current burner stability data indicates a decrease in burner stability, the start-up rate is reduced based on the boiler's current burner stability data, the wall temperature distribution data of each area of ​​the heating surface, and the turbine's standby operation requirements. If the difference between the actual main reheat steam pressure and the control target exceeds a preset allowable range, the opening of the high and low pressure bypass regulating valves is adjusted according to the difference to stabilize the pressure. After the pressure stabilizes, the start-up rate is adjusted based on the wall temperature distribution data of each area of ​​the heating surface, the boiler's current burner stability data, and the turbine's standby operation requirements.

[0075] Optionally, the start-stop peak-shaving device for the coal-fired power unit can be an electronic device with data processing capabilities, or a functional module within the electronic device, without limitation.

[0076] For example, the electronic device can be a server, which can be a single server or a server cluster consisting of multiple servers. As another example, the electronic device can be a mobile phone, tablet computer, desktop computer, laptop computer, handheld computer, notebook computer, ultra-mobile personal computer (UMPC), netbook, as well as cellular phone, personal digital assistant (PDA), augmented reality (AR), virtual reality (VR) device, and other terminal devices. Furthermore, the electronic device can also be a recording device, video surveillance device, etc. This application does not impose any special limitations on the specific form of the electronic device.

[0077] The following example uses the start-up and shutdown peak-shaving device of a coal-fired power unit as an electronic device. Figure 3 As shown, Figure 3 The hardware structure of an electronic device 300 provided in this application.

[0078] like Figure 3 As shown, the electronic device 300 includes a processor 310, a communication line 320, and a communication interface 330.

[0079] Optionally, the electronic device 300 may also include a memory 340. The processor 310, memory 340, and communication interface 330 can be connected via a communication line 320.

[0080] The processor 310 can be a central processing unit (CPU), a general-purpose processor, a network processor (NP), a digital signal processor (DSP), a microprocessor, a microcontroller, a programmable logic device (PLD), or any combination thereof. The processor 310 can also be any other device with processing capabilities, such as a circuit, device, or software module, without limitation.

[0081] In one example, processor 310 may include one or more CPUs, for example Figure 3 CPU0 and CPU1 in the CPU.

[0082] As an optional implementation, the electronic device 300 may include multiple processors, for example, in addition to processor 310, it may also include processor 370. A communication line 320 is used to transmit information between the components included in the electronic device 300.

[0083] Communication interface 330 is used for communication with other devices or other communication networks. These other communication networks can be Ethernet, Radio Access Network (RAN), Wireless Local Area Networks (WLAN), etc. Communication interface 330 can be a module, circuit, transceiver, or any device capable of enabling communication.

[0084] The memory 340 is used to store instructions. These instructions can be computer programs.

[0085] The memory 340 may be a read-only memory (ROM) or other type of static storage device capable of storing static information and / or instructions; it may also be a random access memory (RAM) or other type of dynamic storage device capable of storing information and / or instructions; it may also be an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical discs, laser discs, optical discs, digital universal optical discs, Blu-ray discs, etc.), disk storage media, or other magnetic storage devices, etc., without limitation.

[0086] It should be noted that the memory 340 can exist independently of the processor 310, or it can be integrated with the processor 310. The memory 340 can be used to store instructions, program code, or some data, etc. The memory 340 can be located inside or outside the electronic device 300, without restriction.

[0087] The processor 310 is configured to execute instructions stored in the memory 340 to implement the communication method provided in the following embodiments of this application. For example, when the electronic device 300 is a terminal or a chip in a terminal, the processor 310 can execute instructions stored in the memory 340 to implement the steps performed by the sending end in the following embodiments of this application.

[0088] As an optional implementation, the electronic device 300 also includes an output device 350 and an input device 360. The output device 350 can be a display screen, speaker, or other device capable of outputting data from the electronic device 300 to the user. The input device 360 ​​can be a keyboard, mouse, microphone, joystick, or other device capable of inputting data into the electronic device 300.

[0089] It should be pointed out that, Figure 3 The structure shown does not constitute a limitation on the electronic device, except... Figure 3 In addition to the components shown, the electronic device may include more or fewer components than illustrated, or combine certain components, or have different component arrangements.

[0090] The coal-fired power unit start-up and shutdown peak-shaving devices and application scenarios described in this application are intended to more clearly illustrate the technical solutions of this application and do not constitute a limitation on the technical solutions provided in this application. As those skilled in the art will know, with the evolution of coal-fired power unit start-up and shutdown peak-shaving devices and the emergence of new business scenarios, the technical solutions provided in this application are also applicable to similar technical problems.

[0091] This application provides a storage medium storing a program that, when executed by a processor, implements the coal-fired power unit start-up and shutdown peak-shaving method.

[0092] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0093] In a typical configuration, the device includes one or more processors (CPUs), memory, and a bus. The device may also include input / output interfaces, network interfaces, etc.

[0094] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, like read-only memory (ROM) or flash RAM, and memory includes at least one memory chip. Memory is an example of computer-readable media.

[0095] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0096] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0097] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0098] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A method for starting and stopping peak shaving of a coal-fired power unit, characterized in that, The method includes: After receiving the start-up and shutdown peak-shaving instructions from the power grid, the unit load, main steam temperature and reheat steam temperature are adjusted according to the unit's operational stability requirements. Control the turbine to trip and the generator to trip interlock, while keeping the boiler running. Adjust the opening degree of the high and low pressure bypass control valves according to the main reheat steam pressure stability requirements; When the turbine speed drops to the preset range, the turbine's start-up mode is set to bypass mode according to the turbine's standby operation requirements, and the turbine is controlled to start up to the target speed. Adjusting unit load, main steam temperature, and reheat steam temperature according to the unit's operational stability requirements includes: Extract the load adjustment direction and response time limit from the start / stop peak shaving command; Collect current boiler burner stability data, wall temperature distribution data of each area of ​​the heating surface, and turbine speed fluctuation data; Based on the burner stability data and the wall temperature distribution data of each area of ​​the heating surface, the necessity and expected timing of the auxiliary steam header steam source switching and the plant power switching are determined. Based on the response time limit and the expected timing, the load adjustment is divided into stages; Based on the turbine speed fluctuation data and the wall temperature distribution data of each area of ​​the heated surface, the load triggering node for the unit to switch to wet operation is determined, and the load triggering node is associated with the corresponding load adjustment stage. Based on the load adjustment direction and the wall temperature distribution data of each area of ​​the heated surface, the coordination logic between load adjustment and main steam temperature and reheat steam temperature adjustment at each stage is determined to form a load adjustment strategy. Controlling the turbine to accelerate to the target speed includes: After starting the turbine with bypass, monitor the turbine speed fluctuation data, the current boiler burner stability data, and the main reheat steam pressure change trend. If the deviation between the wall temperature of the heated surface and the design tolerance value is within the preset warning range, or if the current burner stability data of the boiler indicates a decrease in burner stability, the start-up rate will be reduced based on the current burner stability data of the boiler, the wall temperature distribution data of each area of ​​the heated surface, and the standby operation requirements of the steam turbine. If the difference between the actual pressure of the main reheat steam and the control target exceeds the preset allowable range, the opening of the high and low pressure bypass regulating valves is adjusted according to the difference to stabilize the pressure. After the pressure stabilizes, the turbine speed is adjusted by combining the wall temperature distribution data of each area of ​​the heating surface, the current burner stability data of the boiler, and the turbine standby operation requirements.

2. The method according to claim 1, characterized in that, Based on the load adjustment direction and the wall temperature distribution data of each region of the heated surface, the coordination logic between load adjustment and main steam temperature and reheat steam temperature adjustment at each stage is determined to form a load adjustment strategy, including: Based on the differences in wall temperature in each region of the heated surface and the deviation of the wall temperature from the design tolerance value, the correlation between the load adjustment range at each stage and the main steam temperature adjustment range and the reheat steam temperature adjustment range is determined. Based on the expected timing of the auxiliary steam header steam source switching and plant power switching, and according to the changes in the unit's thermal state before and after the switching, the adjustment rate of the main steam temperature and reheat steam temperature at each stage is adjusted. By integrating the aforementioned relationships and rate adjustments, the initiation and execution sequence of load adjustments, main steam temperature adjustments, and reheat steam temperature adjustments at each stage are determined, forming a load adjustment strategy that includes the coordination path of load adjustments at each stage with main steam temperature and reheat steam temperature.

3. The method according to claim 2, characterized in that, The method further includes: When the unit load is adjusted to the load trigger node, the feedwater flow rate remains unchanged; Based on the current burner stability data, wall temperature distribution data of each area of ​​the heating surface, and load adjustment requirements for wet operation, the coal feed rate is reduced to enable the unit to switch to wet operation. The water supply path was switched from the main valve to the bypass regulating valve to adapt to the water supply control requirements under wet conditions.

4. The method according to claim 1, characterized in that, Controlling the turbine to trip and the generator interlock to trip, while maintaining boiler flameout, includes: After controlling the turbine to trip and causing the generator to interlock trip, a preset number of burners are kept running based on the current burner stability data of the boiler. Based on the current burner stability data, wall temperature distribution data of each area of ​​the heating surface, and the requirement to maintain the boiler furnace temperature within the preset stable range, the burner air distribution ratio is adjusted to maintain the boiler furnace temperature within the preset stable range, so as to ensure that the boiler does not shut down.

5. The method according to claim 1, characterized in that, Adjust the opening of the high and low pressure bypass control valves according to the main reheat steam pressure stabilization requirements, including: The control target for the main reheat steam pressure is determined based on the current operating status of the boiler burners and the fluctuation of the coal feed rate. At the moment of turbine tripping, the high and low pressure bypass valves are opened to the preset initial opening and maintained for a preset duration to buffer the main reheat steam pressure fluctuation caused by tripping. After the pressure fluctuations have subsided, adjust the opening of the high and low pressure bypass valves according to the difference between the actual pressure of the main reheat steam and the control target.

6. A start-up and shutdown peak-shaving device for a coal-fired power unit, characterized in that, The device includes: The first adjustment module is used to receive start-stop peak-shaving instructions from the power grid and adjust the unit load, main steam temperature and reheat steam temperature according to the unit's operational stability requirements. The control module is used to control the turbine to trip and the generator to interlock trip, and to keep the boiler from shutting down; The second adjustment module is used to adjust the opening of the high and low pressure bypass control valves according to the main reheat steam pressure stabilization requirements. The control module is also used to set the turbine's start-up mode to a bypass mode according to the turbine's standby operation requirements when the turbine speed drops to a preset range, and to control the turbine to start up to the target speed. The first adjustment module is specifically used to extract the load adjustment direction and response time limit from the start-up and shutdown peak shaving command; collect the current boiler burner stability data, wall temperature distribution data of each area of ​​the heating surface, and turbine speed fluctuation data; determine the necessity and expected timing of auxiliary steam header steam source switching and plant power switching based on the burner stability data and the wall temperature distribution data of each area of ​​the heating surface; divide the load adjustment into stages based on the response time limit and the expected timing; determine the load trigger node for the unit to switch to wet operation based on the turbine speed fluctuation data and the wall temperature distribution data of each area of ​​the heating surface, and associate the load trigger node with the corresponding load adjustment stage; and determine the coordination logic between load adjustment and main steam temperature and reheat steam temperature adjustment in each stage based on the load adjustment direction and the wall temperature distribution data of each area of ​​the heating surface, thus forming a load adjustment strategy. The control module is specifically used to monitor turbine speed fluctuation data, current boiler burner stability data, and main reheat steam pressure change trends after starting the turbine in bypass mode. If the deviation between the heating surface wall temperature and the design tolerance value is within a preset warning range, or if the boiler burner stability is determined to be declining based on the current boiler burner stability data, the turbine will reduce the start-up rate according to the current boiler burner stability data, the wall temperature distribution data of each area of ​​the heating surface, and the turbine's standby operation requirements. If the difference between the actual main reheat steam pressure and the control target exceeds a preset allowable range, the high and low pressure bypass valve openings will be adjusted according to the difference to stabilize the pressure. After the pressure stabilizes, the turbine will adjust the start-up rate based on the wall temperature distribution data of each area of ​​the heating surface, the current boiler burner stability data, and the turbine's standby operation requirements.

7. A storage medium, characterized in that, The storage medium includes a stored program, wherein, when the program is executed, it controls the device containing the storage medium to perform the coal-fired power unit start-up and shutdown peak-shaving method as described in any one of claims 1-5.

8. An electronic device, characterized in that, The device includes at least one processor, at least one memory connected to the processor, and a bus; wherein the processor and the memory communicate with each other through the bus; the processor is used to call program instructions in the memory to execute the coal-fired power unit start-up and shutdown peak shaving method as described in any one of claims 1-5.

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