A precise self-adaptive drum water level regulating system

Abstract

A kind of drum water level self-adapting accurate regulation system.Fixed control parameter cannot adapt unit start-stop, steady state, different conditions such as deep peak regulation.The present application includes water-vapor system full parameter acquisition module, acquires full-dimension parameter required by drum water level regulation, provides data support for identification, modeling, regulation;False water level intelligent identification module, accurately identifies false water level phenomenon, distinguishes real water level fluctuation and pressure-induced false fluctuation, eliminates false regulation;Working condition self-adapting modeling module, adapts different operating conditions, dynamically updates control model and parameter, outputs optimal control parameter;Three-impulse collaborative regulation module, integrates water level, feedwater flow, steam flow three-impulse, realizes collaborative accurate regulation, outputs feedwater pump and control valve regulation instruction;Water level closed-loop deviation correction module.The present application is used for drum water level self-adapting accurate regulation.

Description

Technical Field

[0001] This invention relates to a steam drum water level adaptive precision adjustment system. Background Technology

[0002] Steam drum water level is a core protection parameter for boiler operation. Excessive water level can lead to steam carryover and turbine water hammer, while insufficient water level can cause boiler dry burning and tube overheating and rupture. Existing steam drum water level regulation mostly uses traditional three-impulse fixed PID control, which has significant drawbacks: First, it generates false water levels under varying loads and pressure fluctuations, leading to erroneous system adjustments and large water level fluctuations; second, fixed control parameters cannot adapt to different operating conditions such as unit start-up and shutdown, steady-state operation, and deep peak shaving; third, the three-impulse coupled regulation of feedwater flow, steam flow, and water level has low accuracy and poor anti-interference capability; and fourth, there is no specific regulation strategy during unit start-up and shutdown, resulting in an extremely high risk of water level runaway. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a steam drum water level adaptive and precise adjustment system.

[0004] The above objectives are achieved through the following technical solutions: A steam drum water level adaptive precision adjustment system, comprising: The water-steam system full-parameter acquisition module collects all-dimensional parameters required for steam drum water level regulation, providing data support for identification, modeling, and control. The intelligent identification module for false water levels accurately identifies false water level phenomena, distinguishes between real water level fluctuations and pressure-induced false fluctuations, and prevents erroneous adjustments. The adaptive modeling module adapts to different operating conditions, dynamically updates the control model and parameters, and outputs the optimal control parameters. The three-impulse coordinated control module integrates the three impulses of water level, water supply flow, and steam flow to achieve coordinated and precise regulation and outputs adjustment commands for the water supply pump and control valve. The water level closed-loop deviation correction module corrects the adjustment deviation in real time, eliminates steady-state error, and improves long-term control accuracy. The unit start-up and shutdown special adjustment module adopts a dedicated adjustment strategy for special operating conditions during unit start-up and shutdown, and solves the problem of uncontrolled water level during start-up and shutdown.

[0005] The aforementioned steam drum water level adaptive precision adjustment system includes a water-steam system full parameter acquisition module comprising: The water level acquisition unit collects data from the local water level of the steam drum, the remote water level, and data from multiple water level transmitters, and completes data comparison and calibration. The flow acquisition unit collects parameters such as total boiler feedwater flow, superheated steam outlet flow, and desuperheating water flow in real time. The pressure and temperature acquisition unit collects steam drum pressure, feedwater temperature, and main steam temperature, and captures false water level characteristics caused by pressure fluctuations. The operating condition acquisition unit collects unit load commands, load change rate, feedwater pump output, and valve opening parameters.

[0006] The aforementioned steam drum water level adaptive precision adjustment system includes a false water level intelligent identification module comprising: The fluctuation feature extraction unit extracts characteristic parameters such as water level fluctuation rate, pressure change rate, and flow matching deviation. The true / false water level detection unit accurately identifies false water level conditions based on characteristics such as rapid pressure rise and fall, reverse water level fluctuation, and flow mismatch. When the interference shielding unit detects a false water level, it temporarily disables the normal water level adjustment logic to prevent system malfunctions.

[0007] The aforementioned adaptive and precise adjustment system for steam drum water level includes an adaptive modeling module comprising: The operating condition classification unit divides the unit into five core operating conditions: steady state, load increase, load decrease, deep peak shaving, and start-up / shutdown phase. The dynamic model unit constructs a water level-flow-pressure coupled dynamic model for different operating conditions, and fits the water level response characteristics under different operating conditions. The parameter self-tuning unit adaptively tunes the three-impulse PID control parameters, feedforward compensation coefficients, and filter coefficients.

[0008] The aforementioned steam drum water level adaptive precision adjustment system includes a three-impulse coordinated control module comprising: The main deviation adjustment unit generates basic adjustment commands based on the deviation between the set value and the actual value of the steam drum water level. The steam flow feedforward unit adjusts the feedwater flow in advance according to changes in steam flow to offset water level disturbances caused by load fluctuations. The water supply flow feedback unit provides closed-loop correction of water supply flow deviation, stabilizes water supply output, and avoids large fluctuations in flow. The multi-actuator coordination unit links the feedwater pump frequency converter, feedwater regulating valve, and bypass regulating valve to achieve graded adjustment of coarse and fine adjustment. The aforementioned steam drum water level adaptive precision adjustment system includes a water level closed-loop deviation correction module comprising: The steady-state deviation monitoring unit provides real-time statistics on water level steady-state deviation and fluctuation range, and identifies minute cumulative deviations. The dynamic correction unit uses integral fine-tuning to correct small deviations and proportional fast correction to correct large deviations, balancing accuracy and stability. The anti-interference unit introduces adaptive filtering to improve the system's anti-interference capability in response to random disturbances in fuel, air volume, and pressure.

[0009] The aforementioned adaptive and precise adjustment system for steam drum water level includes a unit start-up and shutdown control module comprising: The start-stop condition locking unit identifies the entire process of unit ignition, temperature and pressure rise, grid connection and shutdown, and locks the exclusive adjustment mode. The low-speed steady-state unit uses small-amplitude, slow-rate adjustments during start-up and shutdown to avoid water level fluctuations caused by large movements. The limit protection unit enhances high and low water level protection during start-up and shutdown, and immediately triggers emergency adjustment and alarm if the limit is exceeded. Beneficial effects

[0010] 1. This invention adds a false water level identification and shielding mechanism, which completely solves the problem of erroneous adjustment in traditional systems; the operating condition adaptive parameters are adapted to all operating scenarios, getting rid of the limitations of fixed parameters; the three-impulse coordinated graded adjustment has higher accuracy and stronger stability; the start-stop special strategy fills the gap in adjustment under special operating conditions, greatly improves the safety of steam drum water level control, and effectively avoids the risk of unit failure and shutdown. Attached Figure Description

[0011] Appendix Figure 1 This is a schematic diagram of the present invention. Detailed Implementation

[0012] A steam drum water level adaptive precision adjustment system, comprising: The water-steam system full-parameter acquisition module collects all-dimensional parameters required for steam drum water level regulation, providing data support for identification, modeling, and control. The intelligent identification module for false water levels accurately identifies false water level phenomena, distinguishes between real water level fluctuations and pressure-induced false fluctuations, and prevents erroneous adjustments. The adaptive modeling module adapts to different operating conditions, dynamically updates the control model and parameters, and outputs the optimal control parameters. The three-impulse coordinated control module integrates the three impulses of water level, water supply flow, and steam flow to achieve coordinated and precise regulation and outputs adjustment commands for the water supply pump and control valve. The water level closed-loop deviation correction module corrects the adjustment deviation in real time, eliminates steady-state error, and improves long-term control accuracy. The unit start-up and shutdown special adjustment module adopts a dedicated adjustment strategy for special operating conditions during unit start-up and shutdown, and solves the problem of uncontrolled water level during start-up and shutdown.

[0013] The aforementioned steam drum water level adaptive precision adjustment system includes a water-steam system full parameter acquisition module comprising: The water level acquisition unit collects data from the local water level of the steam drum, the remote water level, and data from multiple water level transmitters, and completes data comparison and calibration. The flow acquisition unit collects parameters such as total boiler feedwater flow, superheated steam outlet flow, and desuperheating water flow in real time. The pressure and temperature acquisition unit collects steam drum pressure, feedwater temperature, and main steam temperature, and captures false water level characteristics caused by pressure fluctuations. The operating condition acquisition unit collects unit load commands, load change rate, feedwater pump output, and valve opening parameters.

[0014] The aforementioned steam drum water level adaptive precision adjustment system includes a false water level intelligent identification module comprising: The fluctuation feature extraction unit extracts characteristic parameters such as water level fluctuation rate, pressure change rate, and flow matching deviation. The true / false water level detection unit accurately identifies false water level conditions based on characteristics such as rapid pressure rise and fall, reverse water level fluctuation, and flow mismatch. When the interference shielding unit detects a false water level, it temporarily disables the normal water level adjustment logic to prevent system malfunctions.

[0015] The aforementioned adaptive and precise adjustment system for steam drum water level includes an adaptive modeling module comprising: The operating condition classification unit divides the unit into five core operating conditions: steady state, load increase, load decrease, deep peak shaving, and start-up / shutdown phase. The dynamic model unit constructs a water level-flow-pressure coupled dynamic model for different operating conditions, and fits the water level response characteristics under different operating conditions. The parameter self-tuning unit adaptively tunes the three-impulse PID control parameters, feedforward compensation coefficients, and filter coefficients.

[0016] The aforementioned steam drum water level adaptive precision adjustment system includes a three-impulse coordinated control module comprising: The main deviation adjustment unit generates basic adjustment commands based on the deviation between the set value and the actual value of the steam drum water level. The steam flow feedforward unit adjusts the feedwater flow in advance according to changes in steam flow to offset water level disturbances caused by load fluctuations. The water supply flow feedback unit provides closed-loop correction of water supply flow deviation, stabilizes water supply output, and avoids large fluctuations in flow. The multi-actuator coordination unit links the feedwater pump frequency converter, feedwater regulating valve, and bypass regulating valve to achieve graded adjustment of coarse and fine adjustment. The aforementioned steam drum water level adaptive precision adjustment system includes a water level closed-loop deviation correction module comprising: The steady-state deviation monitoring unit provides real-time statistics on water level steady-state deviation and fluctuation range, and identifies minute cumulative deviations. The dynamic correction unit uses integral fine-tuning to correct small deviations and proportional fast correction to correct large deviations, balancing accuracy and stability. The anti-interference unit introduces adaptive filtering to improve the system's anti-interference capability in response to random disturbances in fuel, air volume, and pressure.

[0017] The aforementioned adaptive and precise adjustment system for steam drum water level includes a unit start-up and shutdown control module comprising: The start-stop condition locking unit identifies the entire process of unit ignition, temperature and pressure rise, grid connection and shutdown, and locks the exclusive adjustment mode. The low-speed steady-state unit uses small-amplitude, slow-rate adjustments during start-up and shutdown to avoid water level fluctuations caused by large movements. The limit protection unit enhances high and low water level protection during start-up and shutdown, and immediately triggers emergency adjustment and alarm if the limit is exceeded.

Claims

1. A steam drum water level adaptive precision adjustment system, characterized in that: Its components include: The water-steam system full-parameter acquisition module collects all-dimensional parameters required for steam drum water level regulation, providing data support for identification, modeling, and control. The intelligent identification module for false water levels accurately identifies false water level phenomena, distinguishes between real water level fluctuations and pressure-induced false fluctuations, and prevents erroneous adjustments. The adaptive modeling module adapts to different operating conditions, dynamically updates the control model and parameters, and outputs the optimal control parameters. The three-impulse coordinated control module integrates the three impulses of water level, water supply flow, and steam flow to achieve coordinated and precise regulation and outputs adjustment commands for the water supply pump and control valve. The water level closed-loop deviation correction module corrects the adjustment deviation in real time, eliminates steady-state error, and improves long-term control accuracy. The unit start-up and shutdown special adjustment module adopts a dedicated adjustment strategy for special operating conditions during unit start-up and shutdown, and solves the problem of uncontrolled water level during start-up and shutdown.

2. The steam drum water level adaptive precision adjustment system according to claim 1, characterized in that: The aforementioned water vapor system full parameter acquisition module includes: The water level acquisition unit collects data from the local water level of the steam drum, the remote water level, and data from multiple water level transmitters, and completes data comparison and calibration. The flow acquisition unit collects parameters such as total boiler feedwater flow, superheated steam outlet flow, and desuperheating water flow in real time. The pressure and temperature acquisition unit collects steam drum pressure, feedwater temperature, and main steam temperature, and captures false water level characteristics caused by pressure fluctuations. The operating condition acquisition unit collects unit load commands, load change rate, feedwater pump output, and valve opening parameters.

3. The steam drum water level adaptive precision adjustment system according to claim 1, characterized in that: The aforementioned intelligent false water level identification module includes: The fluctuation feature extraction unit extracts characteristic parameters such as water level fluctuation rate, pressure change rate, and flow matching deviation. The true / false water level detection unit accurately identifies false water level conditions based on characteristics such as rapid pressure rise and fall, reverse water level fluctuation, and flow mismatch. When the interference shielding unit detects a false water level, it temporarily disables the normal water level adjustment logic to prevent system malfunctions.

4. The steam drum water level adaptive precision adjustment system according to claim 1, characterized in that: The aforementioned adaptive working condition modeling module includes: The operating condition classification unit divides the unit into five core operating conditions: steady state, load increase, load decrease, deep peak shaving, and start-up / shutdown phase. The dynamic model unit constructs a water level-flow-pressure coupled dynamic model for different operating conditions, and fits the water level response characteristics under different operating conditions. The parameter self-tuning unit adaptively tunes the three-impulse PID control parameters, feedforward compensation coefficients, and filter coefficients.

5. The steam drum water level adaptive precision adjustment system according to claim 1, characterized in that: The aforementioned three-impulse coordinated control module includes: The main deviation adjustment unit generates basic adjustment commands based on the deviation between the set value and the actual value of the steam drum water level. The steam flow feedforward unit adjusts the feedwater flow in advance according to changes in steam flow to offset water level disturbances caused by load fluctuations. The water supply flow feedback unit provides closed-loop correction of water supply flow deviation, stabilizes water supply output, and avoids large fluctuations in flow. The multi-actuator coordination unit links the water pump frequency converter, water supply regulating valve, and bypass regulating valve to achieve graded adjustment of coarse and fine adjustment.

6. The steam drum water level adaptive precision adjustment system according to claim 1, characterized in that: The water level closed-loop deviation correction module includes: The steady-state deviation monitoring unit provides real-time statistics on water level steady-state deviation and fluctuation range, and identifies minute cumulative deviations. The dynamic correction unit uses integral fine-tuning to correct small deviations and proportional fast correction to correct large deviations, balancing accuracy and stability. The anti-interference unit introduces adaptive filtering to improve the system's anti-interference capability in response to random disturbances in fuel, air volume, and pressure.

7. The steam drum water level adaptive precision adjustment system according to claim 1, characterized in that: The aforementioned unit start-up and shutdown special adjustment module includes: The start-stop condition locking unit identifies the entire process of unit ignition, temperature and pressure rise, grid connection and shutdown, and locks the exclusive adjustment mode. The low-speed steady-state unit uses small-amplitude, slow-rate adjustments during start-up and shutdown to avoid water level fluctuations caused by large movements. The limit protection unit enhances high and low water level protection during start-up and shutdown, and immediately triggers emergency adjustment and alarm if the limit is exceeded.

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