A control method and system of an adaptive energy-saving fume hood

Abstract

The application discloses a control method and system of a self-adaptive energy-saving fume hood, relates to the technical field of energy-saving control of fume hoods, and obtains the height of a sliding door, the width of the sliding door, a set face wind speed, a personnel in-place result, a minimum exhaust volume result and a target pollutant concentration result in the cabinet of a target fume hood to generate a basic exhaust volume result; when personnel change from being present to being absent or the sliding door is at a preset small opening degree and is stable, a residual judgment window is established, a concentration peak value result before leaving is obtained, and a residual release result is generated in combination with the target pollutant concentration result in the cabinet, a concentration drop amplitude result and a residual release judgment boundary; when the residual release result is in an existing state, a delayed exhaust volume result between the minimum exhaust volume result and the basic exhaust volume result is generated, and the minimum exhaust volume result is generated when the state is ended; and the residual release judgment boundary and a residual exhaust coefficient are corrected according to the concentration rebound after exhaust.

Description

Technical Field

[0001] This invention relates to the field of energy-saving control technology for fume hoods, and more specifically, to a control method and system for an adaptive energy-saving fume hood. Background Technology

[0002] Existing laboratory fume hoods typically use exhaust systems to capture and remove gaseous pollutants, volatile substances, or acid mists generated during experiments within the hood, thereby reducing the risk of pollutants spreading into the laboratory environment. To reduce energy consumption caused by continuous high exhaust, existing variable air volume (VAV) fume hoods generally adjust the exhaust volume based on the door opening, set face velocity, personnel presence, or minimum exhaust volume requirements. This ensures a high exhaust volume when the door opening is large or when someone is operating the equipment, and enters a low exhaust energy-saving state when personnel leave, the door is closed, or the door is slightly open.

[0003] The existing technology has the following shortcomings: Current fume hood energy-saving controls typically use personnel leaving or the door opening to a small degree as the primary trigger for reducing exhaust volume, failing to adequately assess whether pollutants within the hood have completely decayed after the experiment. After volatile reagent transfer, bottle opening for sampling, acid mist handling, or cleaning of laboratory equipment, even after personnel have left or the door is slightly open, residual pollutants may still be released or their concentration may be slowly decreasing within the hood. Directly reducing to minimum exhaust volume at this point can easily lead to insufficient pollutant removal or the risk of escape when the door is reopened. Conversely, using a fixed-delay high exhaust strategy would result in excessively long exhaust times under low-risk conditions, increasing ventilation and air conditioning energy consumption. Therefore, a fume hood control method is urgently needed that can identify the residual release state within the hood during the unattended energy-saving switching phase and adjust the judgment boundary based on the concentration recovery after reducing airflow.

[0004] To address the above problems, this invention proposes a solution. Summary of the Invention

[0005] In order to overcome the above-mentioned defects of the prior art, embodiments of the present invention provide an adaptive energy-saving fume hood control method and system to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A control method for an adaptive energy-saving fume hood includes the following steps; Step S1: Obtain the door height, door width, set face velocity, personnel presence result, minimum exhaust volume result, and target pollutant concentration result of the target fume hood. Generate a basic exhaust volume result based on the door height, door width, and set face velocity. When the personnel presence result changes from a present state to an unpresent state, or when the door height is at a preset small opening and remains stable for a preset duration, establish a residual judgment window and obtain the maximum value of the target pollutant concentration result within the preset review time before triggering as the peak concentration result before leaving. Step S2: Obtain the concentration baseline result, peak value baseline result, and decrease rate baseline result to form the residual release judgment boundary. Within the residual judgment window, generate the residual release result based on the current target pollutant concentration result in the cabinet, the peak concentration result before leaving, and the concentration decrease rate result. Step S3: Obtain the residual exhaust coefficient. When the residual release result is in the present state, generate a delayed exhaust volume result between the minimum exhaust volume result and the basic exhaust volume result based on the degree to which the current target pollutant concentration result in the cabinet exceeds the concentration benchmark result. When the residual release result is in the end state, generate the minimum exhaust volume result. Step S4: Obtain the low concentration result before the wind reduction, the highest concentration result after the wind reduction, and the allowable recovery benchmark result. Based on the difference between the highest concentration result after the wind reduction and the low concentration result before the wind reduction, correct the residual release judgment boundary and the residual exhaust coefficient.

[0007] In a preferred embodiment, step S1 includes the following: The effective opening area of ​​the sliding door is determined based on the results of the sliding door height and width. Then, the required exhaust volume is generated based on the effective opening area of ​​the sliding door and the set surface wind speed. When the required exhaust volume for operation is lower than the minimum exhaust volume result, the minimum exhaust volume result shall be used as the base exhaust volume result. When the required exhaust volume for operation is higher than the minimum exhaust volume result, the required exhaust volume for operation shall be used as the basic exhaust volume result. An effective operating area is set in front of the target fume hood opening. When the personnel detection component continuously detects personnel in the effective operating area and the detection duration reaches the preset on-site confirmation time, the personnel on-site result is generated as a person-occupied state. If no personnel are detected within the effective operating area or the detection duration does not reach the preset on-site confirmation time, the personnel on-site result will be generated as an unmanned state. When the height of the sliding door is less than or equal to the preset small opening height and continues to reach the preset small opening stability time, the small opening result of the sliding door is generated as a satisfied state. When the result of the personnel being in place changes from "personnel present" to "no one present", or when the result of the door being slightly open changes from "unsatisfied" to "satisfied", a residual judgment window is established.

[0008] In a preferred embodiment, step S2 includes the following: The residual release results include the existence state, the candidate termination state, and the termination state; When the current concentration of the target pollutant in the cabinet is higher than the concentration baseline, the residual release result is directly generated as an existing state; When the current concentration of the target pollutant in the cabinet is not higher than the concentration benchmark, if the peak concentration before leaving is higher than the peak benchmark and the concentration decrease does not reach the decrease benchmark, then the residual release result is generated as an existing state. If the peak concentration result before departure is higher than the peak baseline result and the concentration decrease result reaches the decrease baseline result, then the residual release result is generated as the termination candidate state; If the peak concentration result before departure is not higher than the peak baseline result, then the residual release result is directly generated as the candidate state for termination; A candidate state must remain continuously for the required duration before it can be confirmed as an ended state. If, within the confirmation period, the concentration of the target pollutant in the cabinet exceeds the baseline concentration again or shows a continuous upward trend, the candidate status for ending the confirmation period will be revoked and the residual release result will be regenerated as the existing status.

[0009] In a preferred embodiment, step S3 includes the following: When the personnel presence result is "occupied", the final exhaust command result uses the basic exhaust volume result; When the personnel presence result is "unmanned" and the residual release result is "existing", a delayed exhaust volume result is generated. The delayed exhaust volume result is set as high hold exhaust volume, medium hold exhaust volume, or low hold exhaust volume according to the degree to which the current target pollutant concentration result in the cabinet exceeds the concentration benchmark result. The hold exhaust volume is determined by the minimum exhaust volume result, the basic exhaust volume result, and the residual exhaust coefficient. When the final exhaust command result generated in the current control cycle is higher than the exhaust command result in the previous control cycle, the exhaust volume is increased according to the faster updraft slope. When the final exhaust command result generated in the current control cycle is lower than the exhaust command result in the previous control cycle, the exhaust volume is reduced according to the slower descent slope, where the rise slope is greater than the fall slope.

[0010] In a preferred embodiment, step S4 includes the following: Determine a valid air reduction process: If, within the air reduction observation period, personnel do not re-enter the effective operating area, the door height does not exceed the preset minimum opening height again, the pollutant detection components inside the cabinet do not malfunction, and the exhaust execution components operate normally, then this air reduction process is marked as a valid air reduction process. For an effective wind reduction process, if the difference between the highest concentration result after wind reduction and the lowest concentration result before wind reduction is greater than the allowable rebound benchmark result, then the wind reduction rebound result is generated as an over-limit state, and safety side correction is performed, including increasing the residual exhaust coefficient, reducing the concentration benchmark result, or increasing the reduction magnitude benchmark result. When the result of the wind rise is within the limit, record the number of times it is within the limit; Only when multiple consecutive effective air reduction processes are within the limit and no personnel re-operation or abnormal detection occurs will a minor energy-saving correction be implemented, including reducing the residual exhaust coefficient, appropriately relaxing the concentration benchmark result, or the reduction range benchmark result. Each correction shall not exceed the preset single correction range, and the corrected residual exhaust coefficient shall not be lower than the safety lower limit, the corrected concentration benchmark result shall not be higher than the preset safety upper limit, and the corrected reduction benchmark result shall not be lower than the preset safety lower limit.

[0011] An adaptive energy-saving fume hood control system includes: a trigger modeling module, a residual discrimination module, a delayed airflow reduction module, and a boundary correction module, with signal connections between the modules; Triggering the modeling module: Obtain the target fume hood's door height, door width, set surface velocity, personnel presence result, minimum exhaust volume result, and target pollutant concentration result inside the hood. Generate a basic exhaust volume result based on the door height, door width, and set surface velocity. When the personnel presence result changes from occupied to unoccupied, or when the door height is at a preset small opening and remains stable for a preset duration, establish a residual judgment window and obtain the maximum value of the target pollutant concentration result inside the hood within a preset review time before triggering as the peak concentration result before leaving. Residual detection module: acquires the concentration baseline result, peak value baseline result, and decrease rate baseline result to form the residual release judgment boundary. Within the residual judgment window, it generates the residual release result based on the current target pollutant concentration result in the cabinet, the peak concentration result before departure, and the concentration decrease rate result. Delayed exhaust module: Obtains residual exhaust coefficient. When the residual release result is in the present state, it generates a delayed exhaust volume result between the minimum exhaust volume result and the basic exhaust volume result based on the degree to which the current target pollutant concentration in the cabinet exceeds the concentration benchmark result. When the residual release result is in the end state, it generates the minimum exhaust volume result. Boundary Correction Module: Obtains the low concentration result before wind reduction, the highest concentration result after wind reduction, and the allowable recovery benchmark result. Based on the difference between the highest concentration result after wind reduction and the low concentration result before wind reduction, it corrects the residual release judgment boundary and the residual exhaust coefficient.

[0012] The technical effects and advantages of the adaptive energy-saving fume hood control method of the present invention are as follows: This invention establishes a residual release judgment window after personnel leave or the door is opened to a preset small degree. It generates a residual release result using the peak concentration result before departure, the current target pollutant concentration in the fume hood, and the concentration decrease result. This allows the energy-saving reduction of the fume hood to no longer rely solely on personnel status or door opening. It can identify situations where pollutants have not been fully discharged after the experiment, thereby reducing the accumulation of residual pollutants caused by directly reducing to the minimum exhaust volume during unattended energy-saving switching. When the residual release result is present, a delayed reduction exhaust volume result is generated between the minimum exhaust volume result and the basic exhaust volume result. This ensures the fume hood maintains necessary exhaust capacity even when residual pollutants have not completely decayed. Minimum exhaust volume control is only entered after the residual release result is complete. This avoids energy waste caused by maintaining the basic exhaust volume for a long time and reduces the risk of pollutant escape due to premature reduction. The residual release judgment boundary and residual exhaust coefficient are slightly modified based on the difference between the highest concentration result after reduction and the lowest concentration result before reduction. This allows the target fume hood to gradually adjust its reduction conditions according to its own operating status, improving the adaptability of energy-saving control during long-term operation. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the control method for an adaptive energy-saving fume hood according to the present invention.

[0014] Figure 2 This is a schematic diagram of the control system structure of an adaptive energy-saving fume hood according to the present invention. Detailed Implementation

[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] Example: Please refer to Figures 1-2 As shown, this invention discloses a control method for an adaptive energy-saving fume hood, comprising the following steps: Step S1: Obtain the door height, door width, set face velocity, personnel presence result, minimum exhaust volume result, and target pollutant concentration result of the target fume hood. Generate a basic exhaust volume result based on the door height, door width, and set face velocity. When the personnel presence result changes from a present state to an unpresent state, or when the door height is at a preset small opening and remains stable for a preset duration, establish a residual judgment window and obtain the maximum value of the target pollutant concentration result within the preset review time before triggering as the peak concentration result before leaving. Step S2: Obtain the concentration baseline result, peak value baseline result, and decrease rate baseline result to form the residual release judgment boundary. Within the residual judgment window, generate the residual release result based on the current target pollutant concentration result in the cabinet, the peak concentration result before leaving, and the concentration decrease rate result. Step S3: Obtain the residual exhaust coefficient. When the residual release result is in the present state, generate a delayed exhaust volume result between the minimum exhaust volume result and the basic exhaust volume result based on the degree to which the current target pollutant concentration result in the cabinet exceeds the concentration benchmark result. When the residual release result is in the end state, generate the minimum exhaust volume result. Step S4: Obtain the low concentration result before the wind reduction, the highest concentration result after the wind reduction, and the allowable recovery benchmark result. Based on the difference between the highest concentration result after the wind reduction and the low concentration result before the wind reduction, correct the residual release judgment boundary and the residual exhaust coefficient.

[0017] In step S1, the following parameters are obtained: door height, door width, set face velocity, personnel presence, minimum exhaust volume, and target pollutant concentration inside the target fume hood. A basic exhaust volume is generated based on the door height, door width, and set face velocity. When the personnel presence changes from present to absent, or when the door height is at a preset small opening and remains stable for a preset duration, a residual judgment window is established. The maximum value of the target pollutant concentration inside the hood within a preset review time before triggering is obtained as the peak concentration before departure. Specific details include: Identify the target fume hood and collect data on the door status, personnel status, basic exhaust status, and concentration status within the hood during the current control cycle to establish the unmanned energy-saving trigger status required for subsequent residual assessment. The target fume hood is a single variable air volume (VAV) fume hood that requires adaptive energy-saving control. It includes the hood body, sliding door, hood opening, exhaust vent, damper or VAV valve, exhaust actuator, personnel detection device, sliding door detection device, and internal contaminant detection device. The exhaust actuator can be a variable frequency exhaust fan or a VAV valve connected to a centralized exhaust system. The personnel detection device determines whether there are continuously operating personnel in front of the target fume hood. The sliding door detection device obtains the door height. The internal contaminant detection device obtains the contaminant concentration inside the hood. The acquired parameters include: door height, door width, set face velocity, personnel presence, current exhaust volume, minimum exhaust volume, basic exhaust volume, and target pollutant concentration inside the cabinet. The door height is the effective opening height between the lower edge of the door and the work surface or preset baseline during the current control cycle. The door width is the effective opening width of the cabinet opening. The set face velocity is the face velocity required to maintain the pollutant capture capacity of the target fume hood under normal operating conditions. The personnel presence indicates whether there are continuously operating personnel in front of the target fume hood. The current exhaust volume is the actual exhaust volume fed back by the current air valve, exhaust fan, or variable air volume valve. The minimum exhaust volume is the basic ventilation volume that the target fume hood still needs to maintain under energy-saving conditions. The target pollutant concentration inside the cabinet is the pollutant concentration collected by the pollutant detection component during the current control cycle. The basic exhaust volume is the exhaust demand generated according to the existing variable air volume control logic. It should be noted that the basic exhaust volume result is generated using the basic control logic of the existing variable air volume fume hood. The effective opening area of ​​the sliding door is determined based on the results of the sliding door height and width. Then, the required exhaust volume is generated based on the effective opening area of ​​the sliding door and the set surface wind speed. When the required exhaust volume for operation is lower than the minimum exhaust volume result, the minimum exhaust volume result shall be used as the base exhaust volume result. When the required exhaust volume for operation is higher than the minimum exhaust volume result, the required exhaust volume for operation shall be used as the basic exhaust volume result. It ensures that when the sliding door is open, the exhaust volume increases with the increase of the opening area, and when the sliding door is open or closed, the minimum exhaust volume is still maintained. The basic exhaust volume result is only used as a reference for the existing technology and the upper limit of subsequent delayed air reduction. Furthermore, the personnel presence results are generated based on a continuous state, rather than being directly determined by a single human detection signal; An effective operating area is set in front of the target fume hood opening. When the personnel detection component continuously detects personnel within the effective operating area and the detection duration reaches the preset presence confirmation time, a personnel presence result is generated indicating a person is present. If no personnel are detected within the effective operating area, or only a short-term passerby is detected and the duration does not reach the preset on-site confirmation time, the personnel on-site result will be generated as an unmanned state. The preset on-site confirmation duration can be set according to laboratory management requirements and personnel operating habits, for example, it can be set to a certain number of seconds that can distinguish between passing by and actual operation; This can prevent personnel from accidentally triggering the operation state when passing in front of the target fume hood for a short time, and can also prevent actual operators from being mistakenly judged as being in an unattended state when they pause briefly. Furthermore, a small opening result for the sliding door is generated to indicate whether the sliding door has entered a low opening state that can trigger energy-saving judgment; When the sliding door height result is less than or equal to the preset small opening height, and this state continues to reach the preset small opening stable time, the generated sliding door small opening result is considered to be in a satisfied state. When the height of the sliding door is greater than the preset minimum opening height, or when the height of the sliding door is lower than the preset minimum opening height but is still changing frequently, the generated minimum opening result of the sliding door is not satisfied. The preset small opening height can be determined according to the structure of the target fume hood and the safety operating procedures. The preset small opening stabilization time is used to exclude the situation where the sliding door briefly passes through the small opening position but does not close stably. It should be noted that the result of the small opening of the sliding door only indicates that the target fume hood has the appearance conditions to enter the unmanned energy-saving judgment, and does not mean that the pollutants inside the hood have been discharged. The result of the small opening of the sliding door is used as one of the conditions for starting the residual judgment window. Furthermore, when the result of personnel presence changes from "personnel present" to "personless", or the result of door opening changes from "unsatisfactory" to "satisfactory", a residual judgment window is established; The residual judgment window is a continuous monitoring time starting from the moment the unattended energy-saving system is triggered, used to observe whether the concentration inside the cabinet has completed effective decay; The trigger time for unmanned energy saving is determined according to the following logic: if the result of personnel being present changes from a present state to an unmanned state first, then the moment when personnel leave is confirmed is taken as the trigger time for unmanned energy saving. If the result of the small opening of the sliding door first changes to the satisfied state, then the moment when the small opening of the sliding door stabilizes is taken as the moment when energy saving is triggered by no one. If the departure of personnel and the stable small opening of the sliding door occur simultaneously, the moment of simultaneous occurrence shall be taken as the moment of unattended energy saving. Furthermore, before the residual judgment window is established, the concentration peak results before departure are also obtained; The peak concentration result before departure is the maximum value of the target pollutant concentration in the cabinet during the preset review time before the unmanned energy-saving trigger moment. The preset review time is used to cover the operation process that is directly related to the end of this experiment before the personnel leave, such as reagent transfer, opening, cleaning, pouring or short-term evaporation process; If the peak concentration before leaving is high, it indicates that a strong release of pollutants occurred in the cabinet before the personnel left. Even if the current concentration has decreased, there may still be residual release. If the concentration peak before departure is low, it indicates that there was no significant pollutant release peak in this operation, and the risk of subsequent residual release is relatively small. The peak concentration result before departure is not used to control the exhaust volume alone, but serves as an important input for step S2 to determine whether residual release still exists; Furthermore, the concentration results of the target pollutants inside the cabinet are continuously collected within the remaining judgment window; the sampling period of the concentration results of the target pollutants inside the cabinet should match the control period of the fume hood, or be an integer multiple of the control period; If the pollutant detection component inside the cabinet outputs an instantaneous concentration value, the moving average or median value can be processed from several consecutive sampling values ​​to reduce the impact of single-point noise on subsequent judgments. It should be noted that this smoothing process is only used to eliminate isolated outliers and does not change the judgment logic of concentration change trend; When multiple consecutive sample values ​​show a concentration increase or a slow decrease, they should not be masked by filtering. The next step in the process will be determined based on the personnel presence and the degree of door opening. If the personnel presence result is "occupied", the target fume hood will maintain the basic exhaust volume result and will not enter the residual judgment process. If the personnel presence result is "unmanned" and the door opening result is "satisfied", the target fume hood will not directly enter the minimum exhaust volume. Instead, the target pollutant concentration result, the peak concentration result before leaving, the residual judgment window, and the minimum exhaust volume result will be transmitted to step S2. If the personnel are present but the door opening is not met, the system will continue to control according to the basic exhaust volume until the door status is stable or the personnel re-enter the operating area. This step acquires and generates results for the sliding door height, personnel presence, small opening of the sliding door, basic exhaust volume, target pollutant concentration in the cabinet, and peak concentration before departure. A residual judgment window is established when personnel leave or the sliding door enters a small opening state. This step converts these into trigger conditions for subsequent residual release judgment, avoiding premature airflow reduction issues caused by overly simplistic trigger conditions in existing unmanned energy-saving control systems. This step provides step S2 with the target pollutant concentration in the cabinet, the peak concentration before departure, and the residual judgment window, enabling further judgment on whether the pollutants in the cabinet have undergone effective attenuation.

[0018] In step S2, the concentration baseline result, peak value baseline result, and decrease rate baseline result are obtained to form the residual release judgment boundary. Within the residual judgment window, the residual release result is generated based on the current target pollutant concentration in the cabinet, the peak concentration result before departure, and the concentration decrease rate result. The specific content includes: It receives the residual judgment window, the target pollutant concentration result in the cabinet, and the peak concentration result before departure, and generates the residual release result based on the decrease of the concentration in the cabinet within the residual judgment window; The residual release results are used to characterize whether the pollutants inside the target fume hood are still not fully discharged after personnel leave or the door is opened slightly. The residual release results include the existence status, the candidate end status, and the end status. The existence status indicates that the air volume cannot be reduced to the minimum exhaust volume. The candidate end status indicates that the air volume reduction conditions are initially met but still need to be continuously confirmed. The end status indicates that the minimum exhaust volume control is allowed. This step is implemented based on the following parameters: current target pollutant concentration in the cabinet, initial concentration at the window, peak concentration before departure, concentration decrease rate, baseline concentration, peak concentration, decrease rate, and end confirmation time. The current target pollutant concentration in the cabinet is the concentration in the cabinet corresponding to the current control cycle within the residual judgment window; The initial concentration result of the window is the representative value of the cabinet concentration in the preset period after the residual judgment window starts. The average value of multiple sampling values ​​in the previous period can be taken. The peak concentration before departure is the maximum concentration obtained during the review period in step S1. The concentration decrease result is used to represent the degree of decrease between the initial concentration in the window and the current concentration in the cabinet; The concentration baseline result is the baseline that the concentration in the cabinet should not exceed the minimum allowable exhaust volume. Peak baseline results are used to determine whether a high level of pollutant release occurred before personnel left; The baseline result of the decrease is used to determine whether the concentration inside the cabinet has decreased sufficiently. The end confirmation time is used to avoid misjudgment due to low concentration values ​​in a single instance; It should be noted that the concentration baseline result, peak value baseline result, and decrease rate baseline result together constitute the boundary for judging residual release; The judgment boundary can be determined during system initialization based on the usage of the target fume hood, the detection range of the pollutant detection components, laboratory safety management requirements, and on-site commissioning results. It should be noted that the background concentration inside the target fume hood under stable exhaust conditions under no-load conditions can be used as a baseline reference first, and then the concentration baseline result can be determined according to the laboratory's allowable safety margin. Peak baseline results can be higher than concentration baseline results and can be used to identify whether there was a significant release of pollutants before personnel left. The baseline result for the rate of decrease can be set as the percentage decrease or the difference in decrease relative to the initial concentration of the window, used to determine whether the pollutants have been effectively removed; The above boundaries are not fixed and immutable. Step S4 can be slightly modified based on whether the concentration rebounds after the actual wind reduction. Furthermore, the concentration decrease result is generated first. After the residual judgment window begins, the controller acquires multiple concentration sampling values ​​in the cabinet according to the preset sampling period and performs simple smoothing processing on the sampling values. The concentration representative value at the beginning of the residual judgment window is used as the initial concentration result of the window, and the smoothed concentration value of the current control cycle is used as the current target pollutant concentration result in the cabinet. If the current concentration of the target pollutant in the cabinet is lower than the initial concentration at the window, the difference between the two or the percentage decrease is taken as the result of the concentration decrease. If the current concentration of the target pollutant in the cabinet is not lower than the initial concentration of the window, the result of the concentration decrease is recorded as not meeting the decrease requirement; Avoid judging solely based on the absolute value of the current concentration, but rather on whether pollutants inside the cabinet are being continuously discharged; Furthermore, a first-level judgment is made on the current target pollutant concentration result in the cabinet: when the current target pollutant concentration result in the cabinet is higher than the concentration benchmark result, the residual release result is directly generated as the existence state; The judgment logic states that as long as the concentration of pollutants inside the cabinet still exceeds the concentration boundary for allowing low air volume operation, the target fume hood must not directly enter the minimum exhaust volume, so as to avoid premature reduction of air volume due to unattended energy-saving logic when the current pollutant concentration is still high. Furthermore, when the current concentration of the target pollutant in the cabinet is not higher than the concentration baseline, the second level of judgment is entered, which combines the peak concentration result before leaving and the concentration decrease result for judgment. If the peak concentration result before leaving is higher than the peak baseline result, it indicates that a high level of pollutant release occurred before the personnel left. In this case, even if the current concentration in the cabinet is temporarily lower than the concentration baseline result, it cannot be immediately confirmed that the residual release has ended. Further assessment is needed to determine whether the concentration decrease has reached the baseline result. If the concentration decrease does not reach the baseline decrease result, the residual release result is generated as an existing state; If the concentration decrease reaches the baseline decrease result, the residual release result is generated as the candidate state for termination. It should be noted that the second layer of judgment is used to solve the problem of misjudging low concentration values ​​in a single instance. Pollutant detection components may experience short-term fluctuations, and exhaust disturbances may also cause the concentration near the sensor to temporarily decrease. If a peak release occurred before leaving, but the concentration decrease process was not sufficient, there may still be residual pollutants remaining. Therefore, it is required that the concentration decrease condition must be met after the peak release in order to enter the candidate state of termination. Furthermore, when the current concentration of the target pollutant in the cabinet is not higher than the concentration baseline, and the peak concentration before leaving is not higher than the peak baseline, the residual release result can be directly generated as the candidate state for termination. No significant pollutant release peak was observed during this operation, and the current concentration already meets the concentration benchmark for allowing low airflow operation. Therefore, it is not necessary to conduct a strict attenuation judgment based on the high peak release scenario. Furthermore, an ending candidate state must be maintained continuously for the specified ending confirmation duration before it can be confirmed as an ending state. Once the residual release result first enters the candidate state for termination, the concentration of the target pollutant in the cabinet will continue to be monitored in subsequent control cycles. If, within the confirmation period, the current concentration of the target pollutant in the cabinet remains no higher than the baseline concentration and there is no significant increase compared to the previous stage, the residual release result is confirmed as the end state. If, within the confirmation period, the concentration of the target pollutant in the cabinet exceeds the baseline concentration again, or shows a continuous upward trend, the candidate status for termination will be revoked, and the residual release result will be regenerated as the existing status. Furthermore, protection against detection anomalies is implemented; If the contaminant detection component inside the cabinet experiences data loss, continuously outputs the same fixed value, exceeds the detection range, or the single jump amplitude exceeds the preset abnormal amplitude within the residual judgment window, the residual release result will not be generated as the end state, but will remain as the existence state or enter the detection abnormality hold state. If the abnormality is maintained, the target fume hood continues to operate according to the delayed reduction in exhaust volume or the basic exhaust volume in step S3, and outputs a detection and maintenance prompt. For example, after the target fume hood completes the transfer of volatile reagents, personnel leave and close the sliding door, and the concentration inside the hood shows a significant peak before leaving; If, after the residual judgment window begins, the current concentration in the cabinet drops below the concentration baseline result for a short period of time, but the decrease is insufficient relative to the initial concentration of the window, the residual release result is still determined to be present. If the concentration inside the cabinet remains below the concentration baseline for multiple consecutive control cycles, and has already decreased sufficiently relative to the initial concentration of the window, then it will first enter the candidate state for termination. After the candidate state is continuously maintained for the end confirmation time, the residual release result is confirmed as the end state. In this step, within the residual judgment window established in step S1, the residual release result is generated by combining the current target pollutant concentration in the cabinet, the initial concentration result of the window, the peak concentration result before departure, and the concentration decrease result. This residual release result is then classified into an existing state, a candidate state for termination, and a terminated state. This step identifies whether the pollutants in the cabinet are still in a state of incomplete discharge by checking whether a high concentration release occurs before departure and whether the concentration in the residual judgment window has decreased sufficiently. This reduces the risk of misjudgment caused by single low concentration values, sensor fluctuations, or short-term exhaust disturbances. This step takes over the unmanned energy-saving trigger state and concentration acquisition results provided in step S1 and passes the residual release result to step S3, enabling step S3 to determine whether to execute delayed air reduction or enter minimum exhaust volume control based on whether the residual release has ended.

[0019] In step S3, the residual exhaust coefficient is obtained. When the residual release result is in a state of existence, a delayed exhaust volume result is generated based on the degree to which the current target pollutant concentration in the cabinet exceeds the concentration baseline result, falling between the minimum exhaust volume result and the baseline exhaust volume result. When the residual release result is in a state of termination, the minimum exhaust volume result is generated, specifically including: Based on the residual release result generated in step S2, the final exhaust command result of the target fume hood is generated. An executable delayed air reduction layer is added before the existing unmanned energy-saving air reduction action, so that the target fume hood maintains an exhaust capacity higher than the minimum exhaust volume before the residual release ends, and then smoothly enters the minimum exhaust volume after the residual release ends. This step is implemented based on the following parameters: personnel presence results, basic exhaust volume results, minimum exhaust volume results, current target pollutant concentration in the cabinet results, concentration baseline results, residual release results, residual exhaust coefficient, exhaust command results from the previous control cycle, and final exhaust command results. The residual exhaust coefficient is used to represent the additional exhaust intensity that needs to be maintained relative to the minimum exhaust volume when residual release exists. The exhaust command results from the previous control cycle are used to achieve smooth air reduction. The final exhaust command results are used to convert into damper opening, variable air volume valve flow rate, or exhaust fan frequency. Furthermore, priority will be given to determining personnel based on their availability. If the personnel presence result is "occupied", the target fume hood is in the operation and exhaust state, and the final exhaust command result adopts the basic exhaust volume result. Regardless of the outcome of the residual release, the system will not perform unattended energy-saving wind reduction. Furthermore, when the personnel presence result is "unmanned" and the residual release result is "existent", the delayed reduction and exhaust volume result is generated. The delayed exhaust volume result is the exhaust volume between the minimum exhaust volume result and the baseline exhaust volume result. Its generation logic is related to the degree to which the current target pollutant concentration result in the cabinet exceeds the concentration benchmark result. Determine the status of the current target pollutant concentration in the cabinet relative to the concentration baseline: If the current concentration of the target pollutant in the cabinet is significantly higher than the concentration baseline, the delayed exhaust volume result shall be the high maintenance exhaust volume that is close to the baseline exhaust volume result. If the current target pollutant concentration in the cabinet is slightly higher than the concentration baseline, the delayed exhaust volume result shall be the middle exhaust volume between the baseline exhaust volume result and the minimum exhaust volume result. If the current target pollutant concentration in the cabinet is no higher than the concentration benchmark but the residual release result is still in the termination candidate state or confirmation stage, then the delayed exhaust volume result shall be the low maintenance exhaust volume that is slightly higher than the minimum exhaust volume result. It should be noted that the high, medium, and low hold-up exhaust volumes can all be determined by the minimum exhaust volume result, the baseline exhaust volume result, and the residual exhaust coefficient. For example, the high hold-up exhaust volume can be set to the baseline exhaust volume result or an exhaust volume close to the baseline exhaust volume result; the medium hold-up exhaust volume can be set to the intermediate value between the minimum exhaust volume result and the baseline exhaust volume result; the low hold-up exhaust volume can be set to an exhaust volume slightly higher than the minimum exhaust volume result; the residual exhaust coefficient is used to fine-tune the above hold-up exhaust volumes. When step S4 determines that the concentration rebounds too much after the airflow is reduced, the residual exhaust coefficient is increased, thereby increasing the overall hold-up exhaust volume; when there is no concentration rebound for a long period of time, the residual exhaust coefficient can be slightly reduced, making the hold-up exhaust volume closer to the minimum exhaust volume. Furthermore, when the personnel presence result is an unmanned state and the residual release result is an ended state, the target fume hood is allowed to enter the minimum exhaust volume control, and the final exhaust command result is set to the minimum exhaust volume result; It should be noted that even if the residual release result has ended, the exhaust volume can be gradually reduced to the minimum according to the air reduction and smoothing logic to avoid sudden changes in the exhaust volume causing disturbances in the flow field inside the cabinet or a short-term rebound in concentration. Furthermore, the final exhaust command result is subjected to amplitude limiting processing; If the final exhaust command result obtained according to the hierarchical logic is lower than the minimum exhaust volume result, then the final exhaust command result will be corrected to the minimum exhaust volume result. If the final exhaust command result is higher than the basic exhaust volume result, the final exhaust command result will be corrected to the basic exhaust volume result. Furthermore, the execution logic for prioritizing rising winds and smoothing falling winds is set; When the final exhaust command result generated in the current control cycle is higher than the exhaust command result in the previous control cycle, the controller increases the exhaust volume according to the faster air rise slope. When the final exhaust command result generated in the current control cycle is lower than the exhaust command result in the previous control cycle, the controller reduces the exhaust volume at a slower descent rate. The upward slope is greater than the downward slope; Reflecting the principle of safety first: When the concentration inside the cabinet increases or the residual release results reappear, it is necessary to quickly increase the exhaust ventilation. When the concentration inside the cabinet decreases and energy conservation is in progress, the exhaust air should be reduced slowly to prevent insufficient removal of pollutants due to a sudden drop in airflow. Furthermore, the final exhaust command result is converted into an execution command for the target fume hood; If the target fume hood uses a damper control method, the controller generates a damper opening command based on the calibration relationship between the exhaust volume and the damper opening. If the target fume hood is controlled by a variable air volume valve, the controller generates the target flow command for the variable air volume valve based on the final exhaust command result. If the target fume hood uses a variable frequency exhaust fan control method, the controller generates an exhaust fan frequency command based on the calibration relationship between the exhaust volume and the exhaust fan frequency. The calibration relationship can be obtained through factory calibration, on-site commissioning, or operational calibration. The controller can use table lookup or linear interpolation to convert the final exhaust command result into an execution command. Furthermore, during the delayed ventilation process, if the personnel presence result changes back to "personnel present" or the door height result changes back to "door height" than the preset small opening height, the delayed ventilation state is immediately exited, and the basic exhaust volume result from step S1 is used again for ventilation. If the pollutant detection component inside the cabinet malfunctions during the delayed airflow process, the controller will not enter the minimum exhaust volume, but will maintain the exhaust volume or the basic exhaust volume, and output a detection malfunction prompt. If the current target pollutant concentration in the cabinet continues to rise during the delayed airflow process, the controller will re-regard the residual release result as existing and increase the final exhaust command result to the high hold exhaust volume or the basic exhaust volume result. This step generates the final exhaust command result based on the residual release result generated in step S2. When the residual release result is in the present state, the target fume hood maintains a delayed exhaust volume higher than the minimum exhaust volume result. When the residual release result is in the end state, the target fume hood smoothly enters the minimum exhaust volume control. This step adds an executable intermediate exhaust layer during the unmanned energy-saving switching process, so that the fume hood will not jump directly from the basic exhaust volume to the minimum exhaust volume. This allows the necessary exhaust capacity to be maintained even before the pollutants in the cabinet have finished decaying, while avoiding energy waste caused by maintaining the basic exhaust volume for a long time. This step uses the residual release result of the previous step as the control basis and leaves the concentration change result after the reduction of air volume to step S4 for boundary correction. It can further optimize the subsequent judgment and exhaust control based on the actual reduction of air volume effect.

[0020] In step S4, the low concentration result before the wind reduction, the highest concentration result after the wind reduction, and the allowable recovery benchmark result are obtained. Based on the difference between the highest concentration result after the wind reduction and the low concentration result before the wind reduction, the residual release judgment boundary and the residual exhaust coefficient are corrected. Specific contents include: The results of the airflow recovery are generated based on the changes in the concentration inside the cabinet after the airflow reduction. The residual release judgment boundary and residual exhaust coefficient are slightly modified based on the results of the airflow recovery. The purpose of this step is to make steps S2 and S3 more consistent with the actual pollutant discharge characteristics of the target fume hood in long-term operation, and to modify the subsequent judgment boundary based on whether the concentration recovers after the airflow reduction. This step is implemented based on the following parameters: low concentration before air reduction, highest concentration after air reduction, air reduction rebound result, allowable rebound baseline result, residual exhaust coefficient, concentration baseline result, peak value baseline result, air reduction range baseline result, single correction range, and effective air reduction process marker. The low concentration before air reduction is a representative low value of the concentration inside the target fume hood during a stable period before air reduction; it can be the average of multiple concentration values ​​or a lower stable value within that stable period. The highest concentration after air reduction is the highest concentration reached inside the hood during an observation period after air reduction. The air reduction rebound result characterizes whether the concentration inside the hood has rebounded beyond the allowable range after air reduction. The allowable rebound baseline result is the acceptable concentration rebound range after air reduction. The single correction range limits the size of each boundary correction. The effective air reduction process marker determines whether this air reduction process can be used for boundary correction. Furthermore, first determine the effective precipitation process; If, during the wind reduction observation period, personnel do not re-enter the effective operating area of ​​the target fume hood, the door height does not exceed the preset minimum opening height again, the pollutant detection components inside the hood do not malfunction, and the exhaust execution components can execute normally according to the final exhaust command, then this wind reduction process will be marked as an effective wind reduction process. If, during the wind reduction observation period, personnel re-operate, the sliding door reopens, the detection component malfunctions, the execution component fails, or manual forced ventilation occurs, the wind reduction process will be marked as an invalid wind reduction process. Invalid wind reduction processes are not used to correct judgment boundaries, but are only saved as operation records to prevent abnormal operation behavior from affecting the system's learning of the residual release decay law; Furthermore, for an effective windfall process, a windfall rebound result is generated, and the highest concentration result after the windfall is compared with the lowest concentration result before the windfall. If the difference between the two is greater than the allowable recovery benchmark result, then the generated wind recovery result is an over-limit state; If the difference between the two is not greater than the allowable rebound benchmark result, then the generated wind speed rebound result is in an unexceeded state; If the concentration inside the cabinet rises significantly after the air is reduced, it indicates that the previous assessment of residual release may have ended too early, or that the air volume for delayed air reduction was insufficient. If the concentration does not rise significantly after the wind decreases, it indicates that the wind decrease is acceptable under the current assessment criteria. Furthermore, when the result of the wind rise is in an excessive state, a safety-side correction is performed, which includes increasing the residual exhaust coefficient or tightening the residual release judgment boundary. After increasing the residual exhaust coefficient, step S3 will generate a higher delayed exhaust volume under the same or similar operating conditions, so that the target fume hood retains more exhaust capacity when residual release exists. Tightening the threshold for judging residual release can include lowering the concentration baseline result or increasing the baseline result for the magnitude of the decrease; After lowering the concentration baseline result, step S2 requires the concentration in the cabinet to drop to an even lower level before the residual release can be terminated; After improving the baseline result of the decrease, step S2 requires that the concentration in the cabinet has a more significant decrease relative to the initial concentration at the window before it is allowed to enter the candidate state of termination. Furthermore, when the result of the wind rise is within the limit, the judgment boundary is not immediately relaxed significantly, but the number of times the limit is not exceeded is recorded; Only when multiple consecutive effective wind reduction processes are within the limit and no personnel re-operation or abnormal detection occurs during these effective wind reduction processes will a minor energy-saving adjustment be implemented. Minor adjustments to the energy-saving side may include reducing the residual exhaust coefficient, or, within a safe range, moderately relaxing the concentration baseline and the reduction baseline. After reducing the residual exhaust coefficient, the delayed exhaust volume generated in step S3 when residual release exists will be closer to the minimum exhaust volume. By appropriately relaxing the concentration benchmark or the decrease benchmark, step S2 can more quickly confirm the end status in low-risk residual release scenarios. It should be noted that the boundary adjustment adopts a small, limited, and fallback-friendly approach to avoid over-relaxation due to a small number of samples or occasional fluctuations. Each increase or decrease in the residual exhaust coefficient must not exceed the preset single correction range; The revised residual exhaust coefficient shall not be lower than the lower safety limit, nor higher than the upper limit that the equipment can perform. The revised concentration baseline result must not exceed the preset safety upper limit; The revised baseline result of the descent range shall not be lower than the preset safety lower limit; if the subsequent wind rise exceeds the limit, the safety side correction can be re-executed to bring the judgment boundary back to a more conservative state. Furthermore, the judgment boundary is only corrected for the same target fume hood, and the correction result of one fume hood is not directly applied to other fume hoods; Different fume hoods may have different cabinet structures, exhaust ducts, sensor locations, and actuator response characteristics. Even if the same residual release judgment process is used, their actual concentration decay rates may differ. The correction results of this step are linked to and saved with the target fume hood identifier; If the target fume hood has its pollutant detection components replaced, its exhaust execution components adjusted, or its sensor installation location changed, the initial judgment boundary can be reactivated, and the effective airflow process can be re-accumulated. Furthermore, the residual release judgment result, final exhaust command result, reduction and rise result, and corrected judgment boundary are recorded for each effective reduction process to form an operation record, which is used by maintenance personnel to check whether the target fume hood frequently exceeds the reduction and rise limit; If the limit is exceeded during multiple consecutive effective air reduction processes, even if the residual exhaust coefficient has been increased and the judgment boundary has been tightened, a maintenance prompt can be output to prompt the inspection of the pollutant detection components, air valve actuators or exhaust duct status inside the cabinet. In this step, the boundary correction module generates a result indicating a rebound in airflow after the concentration change in the hood following the reduction in airflow in step S3. Based on this result, it makes minor, limited, and reversible corrections to the residual release judgment boundary and the residual exhaust coefficient. This step can use the target fume hood's own operating results to correct subsequent residual release judgment logic: when the concentration rebounds significantly after the reduction in airflow, the system tightens the judgment boundary or increases the residual exhaust coefficient to reduce premature reduction in airflow; when no significant rebound occurs during continuous effective reduction in airflow, the system can appropriately relax the judgment boundary within a safe range to reduce unnecessary delayed exhaust. This step forms a closed loop with the previous steps; step S1 establishes the unmanned energy-saving trigger state and provides the basic exhaust volume result; step S2 generates the residual release result based on the concentration decay state in the cabinet; step S3 generates the delayed reduction exhaust volume result based on the residual release result; step S4 corrects the subsequent residual release judgment boundary based on whether the concentration rebounds after the reduction of exhaust volume; through this closed loop, the target fume hood can gradually adjust when it is allowed to reduce to the minimum exhaust volume and how much exhaust volume is retained when residual release exists during operation, thereby solving the problem of premature reduction of exhaust volume in existing unmanned energy-saving control before the pollutants in the cabinet have completed decay, while avoiding unnecessary energy consumption caused by long-term use of fixed high exhaust volume.

[0021] This invention discloses an adaptive energy-saving fume hood control system, comprising: a trigger modeling module, a residual discrimination module, a delayed airflow reduction module, and a boundary correction module, wherein the modules are connected by signals. Triggering the modeling module: Obtain the target fume hood's door height, door width, set surface velocity, personnel presence result, minimum exhaust volume result, and target pollutant concentration result inside the hood. Generate a basic exhaust volume result based on the door height, door width, and set surface velocity. When the personnel presence result changes from occupied to unoccupied, or when the door height is at a preset small opening and remains stable for a preset duration, establish a residual judgment window and obtain the maximum value of the target pollutant concentration result inside the hood within a preset review time before triggering as the peak concentration result before leaving. Residual detection module: acquires the concentration baseline result, peak value baseline result, and decrease rate baseline result to form the residual release judgment boundary. Within the residual judgment window, it generates the residual release result based on the current target pollutant concentration result in the cabinet, the peak concentration result before departure, and the concentration decrease rate result. Delayed exhaust module: Obtains residual exhaust coefficient. When the residual release result is in the present state, it generates a delayed exhaust volume result between the minimum exhaust volume result and the basic exhaust volume result based on the degree to which the current target pollutant concentration in the cabinet exceeds the concentration benchmark result. When the residual release result is in the end state, it generates the minimum exhaust volume result. Boundary Correction Module: Obtains the low concentration result before wind reduction, the highest concentration result after wind reduction, and the allowable recovery benchmark result. Based on the difference between the highest concentration result after wind reduction and the low concentration result before wind reduction, it corrects the residual release judgment boundary and the residual exhaust coefficient.

[0022] The above formulas are all dimensionless calculations. The formulas are derived from software simulations based on a large amount of collected data to obtain the most recent real-world results. The preset parameters in the formulas are set by those skilled in the art according to the actual situation.

[0023] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, in the form of a computer program product.

[0024] Those skilled in the art will recognize that the modules and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and inventive constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0025] In addition, the functional modules in the various embodiments of this application can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module.

[0026] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0027] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A control method for an adaptive energy-saving fume hood, characterized in that, Includes steps; Step S1: Obtain the door height, door width, set face velocity, personnel presence result, minimum exhaust volume result, and target pollutant concentration result of the target fume hood. Generate a basic exhaust volume result based on the door height, door width, and set face velocity. When the personnel presence result changes from a present state to an unpresent state, or when the door height is at a preset small opening and remains stable for a preset duration, establish a residual judgment window and obtain the maximum value of the target pollutant concentration result within the preset review time before triggering as the peak concentration result before leaving. Step S2: Obtain the concentration baseline result, peak value baseline result, and decrease rate baseline result to form the residual release judgment boundary. Within the residual judgment window, generate the residual release result based on the current target pollutant concentration result in the cabinet, the peak concentration result before leaving, and the concentration decrease rate result. Step S3: Obtain the residual exhaust coefficient. When the residual release result is in the present state, generate a delayed exhaust volume result between the minimum exhaust volume result and the basic exhaust volume result based on the degree to which the current target pollutant concentration result in the cabinet exceeds the concentration benchmark result. When the residual release result is in the end state, generate the minimum exhaust volume result. Step S4: Obtain the low concentration result before the wind reduction, the highest concentration result after the wind reduction, and the allowable recovery benchmark result. Based on the difference between the highest concentration result after the wind reduction and the low concentration result before the wind reduction, correct the residual release judgment boundary and the residual exhaust coefficient.

2. The control method for an adaptive energy-saving fume hood according to claim 1, characterized in that, The effective opening area of ​​the sliding door is determined based on the results of the sliding door height and width. Then, the required exhaust volume is generated based on the effective opening area of ​​the sliding door and the set surface wind speed. When the required exhaust volume for operation is lower than the minimum exhaust volume result, the minimum exhaust volume result shall be used as the base exhaust volume result. When the required exhaust volume for operation is higher than the minimum exhaust volume result, the required exhaust volume for operation shall be used as the base exhaust volume result.

3. The control method for an adaptive energy-saving fume hood according to claim 2, characterized in that, An effective operating area is set in front of the target fume hood opening. When the personnel detection component continuously detects personnel in the effective operating area and the detection duration reaches the preset on-site confirmation time, the personnel on-site result is generated as a person-occupied state. If no personnel are detected within the effective operating area or the detection duration does not reach the preset on-site confirmation time, the personnel on-site result will be generated as an unmanned state. When the sliding door height result is less than or equal to the preset small opening height and continues to reach the preset small opening stable time, the generated sliding door small opening result is in a satisfied state; When the result of the personnel being in place changes from "personnel present" to "no one present", or when the result of the door being slightly open changes from "unsatisfied" to "satisfied", a residual judgment window is established.

4. The control method for an adaptive energy-saving fume hood according to claim 1, characterized in that, The residual release results include the existence state, the candidate termination state, and the termination state; When the current concentration of the target pollutant in the cabinet is higher than the concentration baseline, the residual release result is directly generated as an existing state; When the current concentration of the target pollutant in the cabinet is not higher than the concentration benchmark, if the peak concentration before leaving is higher than the peak benchmark and the concentration decrease does not reach the decrease benchmark, then the residual release result is generated as an existing state. If the peak concentration result before departure is higher than the peak baseline result and the concentration decrease result reaches the decrease baseline result, then the residual release result is generated as the termination candidate state; If the peak concentration result before departure is not higher than the peak baseline result, then the residual release result is directly generated as the candidate state for termination.

5. The control method for an adaptive energy-saving fume hood according to claim 4, characterized in that, A candidate state must remain continuously for the required duration before it can be confirmed as an ended state. If, within the confirmation period, the concentration of the target pollutant in the cabinet exceeds the baseline concentration again or shows a continuous upward trend, the candidate status for ending the confirmation period will be revoked and the residual release result will be regenerated as the existing status.

6. The control method for an adaptive energy-saving fume hood according to claim 1, characterized in that, When the personnel presence result is "occupied", the final exhaust command result uses the basic exhaust volume result; When the personnel presence result is "unmanned" and the residual release result is "present", a delayed exhaust volume result is generated. The delayed exhaust volume result determines the residual exhaust coefficient according to the degree to which the current target pollutant concentration in the cabinet exceeds the concentration benchmark result. The residual exhaust coefficient takes a value between the preset safety lower limit and the preset safety upper limit. The delayed exhaust volume result is equal to the minimum exhaust volume result plus the residual exhaust coefficient multiplied by the difference between the basic exhaust volume result and the minimum exhaust volume result.

7. The control method for an adaptive energy-saving fume hood according to claim 6, characterized in that, When the final exhaust command result generated in the current control cycle is higher than the exhaust command result in the previous control cycle, the exhaust volume is increased according to the faster updraft slope. When the final exhaust command result generated in the current control cycle is lower than the exhaust command result in the previous control cycle, the exhaust volume is reduced according to the slower descent slope, where the rise slope is greater than the fall slope.

8. The control method for an adaptive energy-saving fume hood according to claim 1, characterized in that, First, determine the effective wind reduction process: If, within the observation period of wind reduction, personnel do not re-enter the effective operating area, the height of the sliding door does not exceed the preset minimum opening height again, the pollutant detection components inside the cabinet do not malfunction, and the exhaust execution components operate normally, then this wind reduction process will be marked as an effective wind reduction process. For an effective wind reduction process, if the difference between the highest concentration result after the wind reduction and the lowest concentration result before the wind reduction is greater than the allowable rebound benchmark result, then the wind reduction rebound result is generated as an over-limit state, and a safety side correction is performed. The safety-side correction increases the residual exhaust coefficient by a preset single correction margin, or decreases the concentration baseline result by a preset single correction margin, or increases the decrease margin baseline result by a preset single correction margin.

9. The control method for an adaptive energy-saving fume hood according to claim 1, characterized in that, When the result of the wind rise is within the limit, record the number of times it is within the limit; Only when multiple consecutive effective wind reduction processes are within the limit and no personnel re-operation or abnormal detection occurs will a minor energy-saving adjustment be implemented; Small-scale energy-saving corrections include: reducing the residual exhaust coefficient by a preset single correction range, or increasing the concentration baseline result by a preset single correction range, or decreasing the reduction baseline result by a preset single correction range; Each correction shall not exceed the preset single correction range, and the corrected residual exhaust coefficient shall not be lower than the safety lower limit, the corrected concentration benchmark result shall not be higher than the preset safety upper limit, and the corrected reduction benchmark result shall not be lower than the preset safety lower limit.

10. A control system for an adaptive energy-saving fume hood, used to implement the control method for an adaptive energy-saving fume hood according to any one of claims 1-9, characterized in that... ； Triggering the modeling module: Obtain the target fume hood's door height, door width, set surface velocity, personnel presence result, minimum exhaust volume result, and target pollutant concentration result inside the hood. Generate a basic exhaust volume result based on the door height, door width, and set surface velocity. When the personnel presence result changes from occupied to unoccupied, or when the door height is at a preset small opening and remains stable for a preset duration, establish a residual judgment window and obtain the maximum value of the target pollutant concentration result inside the hood within a preset review time before triggering as the peak concentration result before leaving. Residual detection module: acquires the concentration baseline result, peak value baseline result, and decrease rate baseline result to form the residual release judgment boundary. Within the residual judgment window, it generates the residual release result based on the current target pollutant concentration result in the cabinet, the peak concentration result before departure, and the concentration decrease rate result. Delayed exhaust module: Obtains residual exhaust coefficient. When the residual release result is in the present state, it generates a delayed exhaust volume result between the minimum exhaust volume result and the basic exhaust volume result based on the degree to which the current target pollutant concentration in the cabinet exceeds the concentration benchmark result. When the residual release result is in the end state, it generates the minimum exhaust volume result. Boundary Correction Module: Obtains the low concentration result before wind reduction, the highest concentration result after wind reduction, and the allowable recovery benchmark result. Based on the difference between the highest concentration result after wind reduction and the low concentration result before wind reduction, it corrects the residual release judgment boundary and the residual exhaust coefficient.

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