Pathology department air pressure balance system capable of dynamically adjusting air volume and control method

Abstract

The invention relates to the technical field of air pressure regulation and control, in particular to a pathology department air pressure balance system capable of dynamically regulating air volume and a control method. According to the system, the negative pressure of a controlled room is dynamically maintained in real time, harmful gas and pathogenic microorganisms are effectively prevented from leaking outwards, the health of medical staff and the safety of the surrounding environment are protected, it is ensured that each operating ventilation device can obtain the needed exhaust air rate through control over the electric sealing air valve, and the safety of the medical staff is improved. The performance and the safety protection effect of the ventilation equipment are guaranteed, airflow interference generated between different ventilation equipment through exhaust pipelines is avoided, and ventilation according to needs is achieved. According to the control method provided by the invention, the adjustment core is realized by controlling the frequencies of the fresh air handling unit and the exhaust fan, the system response is direct, the logic is clear, the rapid stabilization and dynamic adjustment of the pressure difference of the controlled room are realized through PID control, the frequency of the fan is matched with the air volume requirement according to the on-off state of the ventilation equipment, and the energy consumption is greatly reduced.

Description

Technical Field

[0001] This invention relates to the field of air pressure control technology, and more specifically, to a pathology department air pressure balance system and control method for dynamically adjusting air volume. Background Technology

[0002] The hospital pathology department is a crucial facility for disease diagnosis and pathological research. It typically contains various types of ventilation equipment, including sampling tables, fume hoods, and biosafety cabinets. Currently, the ventilation systems commonly used in hospital pathology departments primarily operate on traditional constant air volume (CAV) or simple variable air volume (VAV) control principles. These systems usually consist of a fresh air handling unit, exhaust fans, and a duct network connecting the various ventilation devices. This maintains a stable negative pressure in the controlled room relative to the external corridor or adjacent areas, ensuring that harmful gases do not diffuse outwards.

[0003] However, existing systems have revealed numerous technical deficiencies in actual operation: poor dynamic response capability; frequent start-up, shutdown, and operation of different ventilation equipment (such as biosafety cabinets, fume hoods, and sample collection cabinets) in the pathology department, resulting in constant changes in the total exhaust volume in the room; the traditional system's fresh air volume and exhaust volume are poorly matched, making it difficult to maintain room pressure differential in real time; when high-volume exhaust ventilation equipment is suddenly shut down, it can easily lead to excessive negative pressure in the room and abnormal equipment operation; conversely, when multiple ventilation equipment is started simultaneously, insufficient exhaust volume may lead to loss of negative pressure, posing a safety hazard; uneven air volume distribution and energy waste; the system lacks linkage control of terminal air valves; when one ventilation equipment is shut down, if its corresponding branch duct cannot be closed in time, it will cause that branch to steal the air volume required by other operating equipment, affecting their normal operation; at the same time, the system continuously operates at maximum or fixed air volume, which will cause huge energy waste when some equipment is shut down, resulting in high operating costs.

[0004] In summary, existing ventilation systems in hospital pathology departments have significant shortcomings in terms of safety, stability, energy efficiency, and intelligent management. Therefore, there is an urgent need in this field for a technical solution that can sense the environmental and equipment status in real time, thereby adjusting the total system airflow and the airflow distribution at each terminal, achieving dynamic air pressure balance and high-efficiency energy-saving operation. Summary of the Invention

[0005] The purpose of this invention is to address the problems existing in the prior art by providing a dynamic airflow regulation system and control method for a pathology ward air pressure balance system. The system provided by this invention maintains negative pressure in the controlled room in real time and dynamically, effectively preventing the leakage of harmful gases and pathogens, maximizing the protection of medical staff's health and the safety of the surrounding environment. By controlling the electrically operated sealing air valves, it ensures that each operating ventilation device receives the required exhaust volume, guaranteeing the performance and safety protection effect of the ventilation equipment, avoiding airflow interference between different ventilation devices through exhaust ducts, and achieving on-demand ventilation. The control method provided by this invention achieves its adjustment primarily through controlling the frequency of the fresh air handling unit and exhaust fan. The system response is direct and the logic is clear. Through PID control, it achieves rapid stabilization and dynamic adjustment of the pressure difference in the controlled room, and matches the fan frequency with the airflow demand according to the on / off status of the ventilation equipment, significantly reducing energy consumption.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A dynamic airflow regulation system for a pathology ward includes a ventilation module, a control module, an environmental monitoring module, and a communication module. The environmental monitoring module includes several sensors that monitor the environmental and equipment status. The output of the environmental monitoring module is electrically connected to the signal input of the communication module. The communication module converts signals from different protocols into a unified data format signal and outputs it to the control module. The control module generates target commands through a built-in control program, and these target commands are transmitted to the ventilation module via the communication module. The ventilation module includes a fresh air handling unit and an exhaust fan. The fresh air handling unit delivers outdoor airflow into the controlled room through fresh air ducts. In the controlled room, several ventilation devices are installed, each connected to an exhaust branch. These exhaust branches are connected to exhaust fans via exhaust ducts. A standard exhaust duct is laid within the controlled room, connecting to the exhaust duct, so that airflow from the controlled room sequentially passes through the standard exhaust duct, the exhaust duct, and the exhaust fan before being exhausted outdoors. A fresh air valve is installed at the air inlet of the fresh air unit, and an electrically adjustable damper is installed on the standard exhaust duct. Electrically sealed dampers are installed at the air outlets of the ventilation devices. The ventilation module adjusts the total fresh air volume, total exhaust air volume, and allocates airflow to each ventilation device according to target instructions.

[0008] Furthermore, the end of the exhaust duct away from the ventilation equipment is connected to the exhaust fan via a filter device, and the airflow is filtered by the filter device and then discharged by the exhaust fan; the environmental monitoring module includes a differential pressure filter sensor to monitor the resistance changes on both sides of the filter screen of the filter device.

[0009] Furthermore, the system is also equipped with an air conditioner, which is connected to the fresh air unit. The total fresh air volume is equal to the sum of the air supply volume of the air conditioner and the air supply volume of the fresh air unit; the total exhaust volume is equal to the sum of the exhaust volume of the ordinary exhaust duct and the exhaust volume of the ventilation equipment.

[0010] Furthermore, the environmental monitoring module includes a fresh air temperature sensor and a fresh air volume sensor respectively installed at the air inlet and air outlet of the fresh air unit, and an exhaust air volume sensor and an exhaust air temperature sensor sequentially installed on the exhaust duct. The fresh air temperature sensor is used to monitor the outdoor air temperature, and the fresh air volume sensor is used to monitor the total fresh air volume; the exhaust air volume sensor is used to monitor the total exhaust air volume of the exhaust duct, and the exhaust air temperature sensor is used to monitor the exhaust air temperature of the exhaust duct.

[0011] Furthermore, the environmental monitoring module also includes a differential pressure sensor, an indoor temperature and humidity sensor group, and an air quality sensor group installed in the controlled room. The differential pressure sensor monitors the pressure difference between the inside and outside of the controlled room, the indoor temperature and humidity sensor group monitors the temperature and humidity in the controlled room, and the air quality sensor group includes several gas concentration sensors for monitoring the concentrations of carbon dioxide, formaldehyde, xylene, and VOCs in the controlled room.

[0012] Furthermore, the control module includes a main controller, an expansion unit, and a device control input / output terminal, as well as a power supply unit. The communication module includes a signal conversion and receiving unit and a signal conversion relay. The output terminal of the power supply unit is electrically connected to the main controller, the expansion unit, and the device control input / output terminal. The main controller is connected to the expansion unit, the expansion unit is connected to the device control input / output terminal, and the device control input / output terminal is connected to the signal conversion and receiving unit and the signal conversion relay. The signal output by the environmental monitoring module is transmitted to the signal conversion and receiving unit, and the target command generated by the control module is sent to the signal conversion relay through the device control input / output terminal. The output terminal of the signal conversion relay is connected to each actuator.

[0013] A method for dynamically adjusting airflow and controlling air pressure balance in a pathology department, the method being based on a dynamically adjusted airflow and air pressure balance system for a pathology department, the method comprising the following steps:

[0014] System initialization and self-test: The system starts up and the control module runs the self-test program; initializes system parameters, sets the target differential pressure value of the controlled room, the target indoor temperature and humidity, and the alarm thresholds for various air quality parameters, and sets the initial frequency of the fresh air unit and exhaust fan to the reference frequency;

[0015] Real-time data acquisition: The sensors in the environmental monitoring module continuously collect data and send the real-time data information to the control module through the communication module. The data information includes air volume data, environmental data, and equipment status data.

[0016] Decision-making and target instruction generation: The control module selects the operating mode, generates target instructions, and executes them based on real-time data information.

[0017] Furthermore, the control module selects an operating mode based on real-time data information. The operating modes include the following:

[0018] Static operating mode: All ventilation equipment is not started, and the system operates according to the preset low load baseline. In the static operating mode, the fresh air unit and exhaust fan initially operate at the reference frequency. The electric sealing air valves of the ventilation equipment are closed, and the electric opening regulating air valves of the ordinary exhaust duct are open at 100%. The control module continuously monitors the pressure difference ΔP between the inside and outside of the controlled room. If ΔP deviates from the target value, the frequency difference between the fresh air unit and the exhaust fan is adjusted to achieve balance.

[0019] Dynamic operating mode: When ventilation equipment starts or stops, the corresponding status signal is sent to the main controller. The control module determines the number of exhaust fans (N) based on the number of currently activated ventilation equipment. 排风 The number of fresh air handling units is N 新风 The system calculates and executes the target frequency of the fan, matches the target frequency f of the fresh air handling unit with the target exhaust frequency f of the fresh air handling unit, and matches the target frequency f of the exhaust fan with the target exhaust frequency of the exhaust fan, so that the total air volume of the system matches the operating requirements of the ventilation equipment. The control module opens the electric sealing air valves corresponding to the operating ventilation equipment and closes the electric sealing air valves corresponding to the non-operating ventilation equipment.

[0020] Air quality emergency: When the air quality sensor group detects that the concentration of any harmful gas exceeds the set threshold, the control module immediately triggers the emergency linkage, the frequency of the fresh air unit and exhaust fan is forcibly set to the maximum value, all electric sealing air valves are switched to the open state, and the human-machine interface triggers an audible and visual alarm.

[0021] Fire emergency response: When the control module receives a fire emergency stop alarm monitoring signal, it immediately sets the frequency of the fresh air unit and exhaust fan to 0Hz and stops the operation of the fresh air unit and exhaust fan.

[0022] Furthermore, when ΔP deviates from the target value, the frequency difference between the fresh air handling unit and the exhaust fan is adjusted through PID control. Let the target pressure difference value of the controlled room be P. 目标 The current actual pressure difference is P. 当前 If the deviation is e(t), then:

[0023] e(t) = P 目标 -P 当前 ;

[0024] When e(t) < 0, the actual negative pressure in the controlled room is insufficient;

[0025] When e(t) > 0, the negative pressure in the controlled room is too high;

[0026] Let the frequency correction be Δf, Δf = P 输出 +I 输出 +D 输出 ,in:

[0027] P 输出 =Kp×e(t;

[0028] I 输出 =Ki×∫e(t)dt;

[0029] D 输出 =Kd×de(t) / dt;

[0030] Kp, Ki, and Kd are constants determined by optimizing and adjusting parameters on-site based on the dynamic characteristics of the controlled system and observing the system response curve.

[0031] The current frequency of the exhaust fan is f. 当前排风 The target frequency of the adjusted exhaust fan is f. 目标排风 The current frequency of the fresh air handling unit is f 当前新风 The target frequency of the adjusted fresh air handling unit is f. 目标新风 ,but:

[0032] When Δf > 0, increase the exhaust volume and decrease the fresh air volume, f 目标排风 =f 当前排风 +Δf,f 目标新风 =f 当前新风 -Δf×k; When Δf < 0, reduce the exhaust volume and increase the fresh air volume, f 目标排风 =f 当前排风 -Δf, f 目标新风 =f 当前新风 +Δf×k; where k takes values ​​from 0.5 to 0.8.

[0033] Furthermore, the algorithm for calculating and executing the target frequency of the wind turbine is as follows: f 目标排风 =5×N 排风 +20; f 目标新风 =4×N 新风 +16; The reference frequency of the exhaust fan is 20Hz, and the reference frequency of the fresh air unit is 16Hz.

[0034] Compared with the prior art, the beneficial effects of the present invention are:

[0035] The system provided by this invention maintains negative pressure in the controlled room in real time and dynamically, effectively preventing the leakage of harmful gases and pathogenic microorganisms, maximizing the protection of the health of medical staff and the safety of the surrounding environment. By controlling the electrically operated sealing air valves, it ensures that each operating ventilation device receives the required exhaust volume, guaranteeing the performance and safety protection of the ventilation equipment, avoiding airflow interference between different ventilation devices through exhaust ducts, and achieving on-demand ventilation. The control method provided by this invention achieves its adjustment primarily through controlling the frequency of the fresh air unit and exhaust fan. The system has a direct response and clear logic. Through PID control, it achieves rapid stabilization and dynamic adjustment of the pressure difference in the controlled room, and matches the fan frequency with the airflow demand according to the on / off status of the ventilation equipment, significantly reducing energy consumption. Attached Figure Description

[0036] Figure 1 This is a system connection diagram of the ventilation module of the present invention;

[0037] Figure 2 This is a schematic diagram of the hardware system structure of the present invention;

[0038] Figure 3 This is an overall system connection diagram of the present invention;

[0039] Figure 4 This is a system connection diagram of the fresh air handling unit of the present invention;

[0040] Figure 5 This is a system connection diagram of the controlled room according to the present invention;

[0041] Figure 6 This is a system connection diagram of the exhaust fan of the present invention;

[0042] In the diagram: 11. Fresh air handling unit; 12. Fresh air duct; 121. Fresh air temperature sensor; 122. Fresh air volume sensor; 123. Fresh air valve; 13. Exhaust fan; 14. Exhaust duct; 141. Exhaust air temperature sensor; 142. Exhaust air volume sensor; 143. Ordinary exhaust duct; 15. Filter device; 16. Ventilation equipment; 17. Electric adjustable damper; 18. Electric sealing damper; 21. Air conditioner; 22. Controlled room; 221. Differential pressure sensor; 222. Indoor temperature and humidity sensor group; 223. Air quality sensor group; 23. Ceiling; 31. Power supply unit; 32. Power conversion unit; 33. Emergency fuse unit; 34. Main controller; 35. Expansion unit; 36. Equipment control input / output terminal; 37. Human-machine interface; 41. Signal conversion and receiving unit; 42. Signal conversion relay;

[0043] The functional descriptions of each signal line are as follows:

[0044] A1. Fresh air valve control; A2. Fresh air temperature signal; A3. Fresh air handling unit start / stop, fan speed control and status monitoring; A4. Fresh air handling unit medium efficiency alarm monitoring; A5. Air conditioning control; A6. Fresh air volume signal;

[0045] B1. Control signal for electrically sealed damper; B2. Equipment start signal; B3. Human-machine interface control signal; B4. Differential pressure signal; B5. Indoor temperature and humidity signal; B6. Air quality signal; B7. Fire emergency stop alarm monitoring; B8. System status alarm; B9. Control signal for electrically adjustable damper.

[0046] C1. Exhaust fan start / stop, speed control and status monitoring; C2. Filter device alarm monitoring; C3. Exhaust air temperature signal; C4. Exhaust air volume signal. Detailed Implementation

[0047] The technical solution of the present invention will be clearly and completely described below. 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.

[0048] Example 1:

[0049] Please see Figure 1-6 A dynamic airflow regulation system for a pathology department includes a ventilation module, a control module, an environmental monitoring module, and a communication module. The environmental monitoring module includes several sensors that monitor the environment and equipment status. The output of the environmental monitoring module is electrically connected to the signal input of the communication module. The communication module converts signals from different protocols into a unified data format signal and outputs it to the control module. The control module generates target commands through a built-in control program, and the target commands are transmitted to the ventilation module via the communication module. The ventilation module includes a fresh air handling unit 11 and an exhaust fan 13. The fresh air handling unit 11 delivers outdoor airflow into the controlled room 22 through a fresh air duct 12. The controlled room 22 is equipped with... Several ventilation devices 16 are connected to exhaust branch lines, which are connected to exhaust fans 13 via exhaust ducts 14. A general exhaust duct 143 is laid in the controlled room 22, which is connected to the exhaust duct 14, so that the airflow in the controlled room 22 is sequentially sent to the outside through the general exhaust duct 143, the exhaust duct 14, and the exhaust fan 13. A fresh air valve 123 is installed at the air inlet of the fresh air unit 11, and an electrically operated opening regulating valve 17 is installed on the general exhaust duct 143. An electrically operated sealing valve 18 is installed at the air outlet of each of the ventilation devices 16. The ventilation module adjusts the total air volume of the system and distributes the air volume of each ventilation device 16 according to the target command.

[0050] The sensors in the environmental monitoring module continuously collect environmental parameters of the controlled room 22 and the operating status of each ventilation device 16, and send the raw signals of different protocols to the communication module. The communication module converts all heterogeneous signals into a unified data format signal and transmits it to the control module to achieve data standardization and integration.

[0051] After receiving the standardized environmental and equipment data signals, the control module performs real-time analysis and calculation by its built-in control program, generates target instructions, and then transmits them to the various actuators of the ventilation module through the communication module.

[0052] The ventilation module coordinates actions according to the target instructions to realize the adjustment of the total air volume of the system, the allocation of the exhaust air volume of each of the 16 ventilation devices, and the adjustment of the background exhaust air.

[0053] Specifically, the total air volume of the system is adjusted by controlling the opening and closing of the fresh air valve 123 and adjusting the frequency of the fresh air unit 11; at the same time, the frequency of the exhaust fan 13 is adjusted synchronously to control the total exhaust volume, so as to ensure that the air volume difference between the total fresh air volume and the total exhaust volume is always maintained to maintain the negative pressure of the controlled room 22.

[0054] Air volume distribution of each ventilation device 16: The total exhaust volume is distributed to the operating ventilation devices 16 by controlling the opening and closing of the electric sealing air valve 18 at the air outlet of each ventilation device 16.

[0055] Background exhaust ventilation adjustment: By adjusting the electric opening regulating valve 17 on the ordinary exhaust duct 143, the background exhaust ventilation of the controlled room 22 is controlled so that the pressure difference between the inside and outside of the controlled room 22 is always maintained regardless of the opening and closing status of the ventilation equipment 16.

[0056] Preferably, the fresh air duct 12 and the ordinary exhaust duct 143 are respectively connected to the air inlet and the air outlet on the ceiling 23 of the controlled room 22.

[0057] Preferably, the ventilation device 16 includes one or more of a biosafety cabinet, a fume hood, and a material handling station.

[0058] It should be noted that the total exhaust volume is equal to the sum of the exhaust volume of the ordinary exhaust duct 143 and the exhaust volume of each ventilation device 16.

[0059] The system provided by this invention maintains negative pressure in the controlled room in real time and dynamically, effectively preventing the leakage of harmful gases and pathogenic microorganisms, and maximizing the protection of the health of medical staff and the safety of the surrounding environment. By controlling the electric sealing air valve 18, it is ensured that each operating ventilation device 16 can obtain the required exhaust volume, guaranteeing the performance and safety protection effect of the ventilation device 16, and avoiding airflow interference between different ventilation devices 16 through the exhaust duct 14.

[0060] The present invention changes the constant air volume operation mode used in the prior art, realizes on-demand ventilation, and closes the electric sealing air valve 18 that controls the ventilation equipment 16 that is not in operation, thus avoiding ineffective energy waste.

[0061] The end of the exhaust duct 14 away from the ventilation equipment 16 is connected to the exhaust fan 13 through the filter device 15. The airflow is filtered by the filter device 15 and then discharged through the exhaust fan 13.

[0062] The polluted airflow in the controlled room 22, under the negative pressure generated by the exhaust fan 13, enters the exhaust duct 14 through the ordinary exhaust duct 143 and the exhaust branch pipes of each ventilation device 16. Under the suction of the exhaust fan 13, the polluted airflow is first forcibly transported to the filter device 15. When the airflow passes through the filter device 15, the harmful substances (such as pathogenic microorganisms, chemical gas aerosols, dust, etc.) are intercepted or adsorbed by the filter material. After purification, the airflow is then discharged into the external atmosphere of the building through the exhaust fan 13.

[0063] The environmental monitoring module includes a differential pressure filter sensor. The system monitors the resistance changes across the filter screen of the filter device 15 using the differential pressure filter sensor. When the differential pressure across the filter screen rises to a set threshold, the control module determines that the filter screen needs to be replaced or maintained and issues an alarm signal. At the same time, when filter screen blockage causes increased exhaust resistance, the system adjusts the frequency of the exhaust fan 13 to maintain the required total exhaust volume, ensuring the stability of system operation.

[0064] Preferably, the system is also equipped with an air conditioner 21, which is connected to a fresh air handling unit 11. The total fresh air volume is equal to the sum of the air supply volume of the air conditioner 21 and the air supply volume of the fresh air handling unit 11.

[0065] The environmental monitoring module includes a fresh air temperature sensor 121 and a fresh air volume sensor 122 installed at the air inlet and air outlet of the fresh air unit 11, respectively, and an exhaust air volume sensor 142 and an exhaust air temperature sensor 141 installed sequentially on the exhaust duct 14. The fresh air temperature sensor 121 is used to monitor the outdoor air temperature, and the fresh air volume sensor 122 is used to monitor the total fresh air volume. The exhaust air volume sensor 142 is used to monitor the total exhaust air volume of the exhaust duct 14, and the exhaust air temperature sensor 141 is used to monitor the exhaust air temperature of the exhaust duct 14.

[0066] This system achieves real-time data acquisition by deploying sensors at key nodes in the air duct. The fresh air temperature sensor 121 probes into the air flowing through the air inlet of the fresh air unit 11 and converts the sensed outdoor air temperature physical quantity into an electrical signal; the fresh air volume sensor 122 measures the airflow velocity at the air outlet of the fresh air unit 11 and, combined with the known duct cross-sectional area, calculates the volumetric flow rate, i.e., the total fresh air volume.

[0067] The exhaust air volume sensor 142 is similar to the fresh air volume sensor 122. It is installed on the exhaust duct 14 and is used to measure the total exhaust airflow, i.e., the total exhaust volume. The exhaust temperature sensor 141 is similar to the fresh air temperature sensor 121. It is installed on the exhaust duct and is used to measure the temperature of the mixed airflow that is about to be discharged to the filter device 15.

[0068] The environmental monitoring module also includes a differential pressure sensor 221, an indoor temperature and humidity sensor group 222, and an air quality sensor group 223 installed in the controlled room 22. The differential pressure sensor 221 monitors the pressure difference between the inside and outside of the controlled room 22, the indoor temperature and humidity sensor group 222 monitors the temperature and humidity in the controlled room 22, and the air quality sensor group 223 includes several gas concentration sensors for monitoring the concentrations of carbon dioxide, formaldehyde, xylene, and VOCs in the controlled room 22.

[0069] One end of the differential pressure sensor 221 is connected to the inside of the controlled room 22 through a sampling tube, and the other end is connected to a reference area (such as an external corridor), thereby measuring the pressure difference between the two ends and outputting a real-time pressure difference signal between the controlled room 22 and the reference area; the indoor temperature and humidity sensor group 222 continuously measures the air temperature and relative humidity values ​​in the controlled room 22 and converts them into electrical signals.

[0070] The air quality sensor group 223 includes sensing units for carbon dioxide, formaldehyde, xylene and VOC gases. The gas concentration sensors convert the concentration values ​​of the corresponding gases into electrical signals that can be read by the system.

[0071] All signals generated by the sensors are transmitted to the communication module. The communication module performs analog-to-digital conversion and protocol unification on the collected signals before sending them to the control module.

[0072] The control module includes a main controller 34, an expansion unit 35, and a device control input / output terminal 36, as well as a power supply unit 31 for power supply. The communication module includes a signal conversion and receiving unit 41 and a signal conversion relay 42.

[0073] The output terminal of the power supply unit 31 is electrically connected to the main controller 34, the expansion unit 35 and the equipment control input / output terminal 36. The power supply unit 31 converts the 380V / AC main power supply to the DC / 24V power supply voltage of the actuator through the power conversion unit 32.

[0074] The main controller 34 is connected to the expansion unit 35 via an internal bus. The expansion unit 35 is connected to the device control input / output terminal 36 via its own interface circuit. The device control input / output terminal 36 is connected to the signal conversion receiving unit 41 and the signal conversion relay. The signal output by the environmental monitoring module is transmitted to the signal conversion receiving unit 41. The target command generated by the control module is sent to the signal conversion relay 42 via the device control input / output terminal 36. The output terminal of the signal conversion relay 42 is connected to each actuator.

[0075] A human-machine interface 37 is installed in the controlled room 22. The human-machine interface 37 is electrically connected to the main controller 34 through a communication module, thereby realizing local control.

[0076] The control module adopts an integrated design of strong and weak current. The main controller 34 is a direct digital controller (DDC), which is connected to the actuator through a local I / O interface.

[0077] In a direct digital controller (DDC), DI serves as a digital input used to receive switching signals.

[0078] The fresh air unit 11 has a built-in medium-efficiency filter. The medium-efficiency filter is existing technology and will not be described in detail here. When the medium-efficiency filter is clogged, an alarm signal is issued. The DI interface receives the status of the medium-efficiency alarm monitoring A4 of the fresh air unit in real time.

[0079] A differential pressure switch sensor is installed on the medium-efficiency filter of the fresh air unit 11. When the pressure difference between the two sides of the filter exceeds the sensor trigger value due to dust accumulation, the electrical contacts inside the medium-efficiency filter change from an open state to a closed state, and the closing signal is transmitted to the DI interface of the main controller 34. The DI interface monitors the continuity of the A4 line in real time. When it detects that the A4 line changes from an open circuit to a closed circuit, the main controller 34 determines that a medium-efficiency filter blockage event has occurred and triggers the alarm information on the human-machine interface 37, thereby notifying the management personnel to perform maintenance.

[0080] The control module also includes an emergency safety unit 33, which constantly monitors the fire status of the system and issues an alarm signal when a fire emergency occurs. The DI interface receives the status of the fire emergency stop alarm monitoring B7 in real time.

[0081] Emergency safety unit 33 independently monitors the building's fire alarm signals. When a fire emergency is confirmed, emergency safety unit 33 outputs a signal to the DI interface of the main controller 34. Once the DI interface detects that the fire emergency stop alarm monitoring B7 line is connected, the main controller 34 immediately stops the operation of the fresh air unit 11 and the exhaust fan 13.

[0082] The resistance change on both sides of the filter screen of the filter device 15 is monitored by the differential pressure filter sensor. When the differential pressure on both sides of the filter screen rises to the set threshold, the control module determines that the filter screen needs to be replaced or maintained and issues an alarm signal. The DI interface receives the status of the filter device alarm monitoring C2 in real time. After the main controller 34 detects that the filter device alarm monitoring C2 line is connected, it determines that the filter device 15 needs maintenance and triggers the alarm information for replacing the filter screen on the human-machine interface 37.

[0083] DO, as a digital output, is used to issue switch command signals.

[0084] A fresh air valve 123 is installed at the air inlet of the fresh air unit 11. The human-machine interface 37 sends a signal to open the fresh air valve 123, and the main controller 34 controls the opening of the fresh air valve 123 through the fresh air valve control A1 line.

[0085] Each ventilation device 16 is equipped with an electric sealing damper 18 at its air outlet. When the ventilation device 16 is running, it sends a signal to open the electric sealing damper 18. The main controller 34 controls the opening of the electric sealing damper 18 through the electric sealing damper control signal.

[0086] The main controller 34 continuously runs a self-diagnostic program and monitors all key parameters in the system. When any parameter exceeds the normal range or a fault occurs, the internal logic of the main controller 34 determines that the system is abnormal and immediately outputs a signal through the system status alarm B8 line to trigger the alarm information on the human-machine interface 37.

[0087] AI is used as an analog input to receive continuously changing signals:

[0088] The fresh air temperature sensor 121 monitors the temperature of the airflow that is about to enter the fresh air unit 11 in real time and transmits the real-time data to the main controller 34 through the fresh air temperature signal A2 line.

[0089] The fresh air volume sensor 122 monitors the total fresh air volume in real time and transmits the real-time data to the main controller 34 through the fresh air volume signal A6 line.

[0090] The differential pressure sensor 221 monitors the pressure difference between the inside and outside of the controlled room 22 in real time and transmits the real-time data to the main controller 34 through the differential pressure signal B4 line.

[0091] The indoor temperature and humidity sensor group 222 monitors the temperature and humidity in the controlled room 22 in real time and transmits the real-time data to the main controller 34 through the indoor temperature and humidity signal B5 line.

[0092] The exhaust temperature sensor 141 monitors the temperature of the airflow in the exhaust duct 14 in real time and transmits the real-time data to the main controller 34 through the exhaust temperature signal C3.

[0093] The exhaust air volume sensor 142 monitors the total exhaust air volume in real time and transmits the real-time data to the main controller 34 through the exhaust air volume signal C4.

[0094] AO, as an analog output, is used to send continuously changing control signals.

[0095] The electric opening regulating damper 17 controls the exhaust volume of the ordinary exhaust duct 143. The electric opening regulating damper 17 is a proportional-integral electric damper actuator (0-10V control) and can adjust the opening from 0 to 100%. The opening adjustment of the electric opening regulating damper 17 is controlled by the electric opening regulating damper control signal B9.

[0096] The signal conversion and receiving unit 41 of the communication module processes RS485 signals, converting signals of different protocols into signals that can be recognized by the main controller 34, thereby realizing data exchange.

[0097] The command control and status information of the fresh air handling unit 11 are transmitted bidirectionally to the main controller 34 through the fresh air handling unit start / stop, wind speed control and status monitoring A3 line; the command control of the air conditioner 21 is transmitted bidirectionally to the main controller 34 through the air conditioner control A5 line; the start-up and operation status of the ventilation equipment 16 is transmitted to the main controller 34 through the equipment start signal B2 line; the operation of the human-machine interface 37 is transmitted to the main controller 34 through the human-machine interface control signal B3 line; the data collected by the air quality sensor group 223 is transmitted to the main controller 34 through the air quality signal B6 line; the command control and status information of the exhaust fan 13 are transmitted bidirectionally to the main controller 34 through the exhaust fan start / stop, wind speed control and status monitoring C1 line.

[0098] This system is centered around a main controller 34, which connects to all devices through various interfaces: Digital input (DI) receives real-time alarm signals from switches such as medium-efficiency filter blockage and fire emergency stop; Analog input (AI) continuously collects environmental parameters such as temperature, humidity, air volume, and room pressure difference of fresh air / exhaust air; Digital output (DO) controls the opening and closing of fresh air valve 123 and electrically sealed air valve 18 and triggers system alarms; Analog output (AO) adjusts the opening of electrically adjustable air valve 17. A human-machine interface 37 provides a window for on-site operation. The core function of the communication module is to perform protocol conversion, unifying heterogeneous signals from different devices such as the fresh air handling unit 11, air conditioner 21, exhaust fan 13, ventilation equipment 16, and air quality sensor group 222 into data recognizable by the main controller 34, thereby achieving bidirectional data exchange and centralized intelligent control between all subsystems.

[0099] The system provided by this invention achieves the adjustment and dynamic response of the pressure difference, air volume and equipment status of the controlled room 22 through centralized processing and direct digital control by the main controller 34. Based on real-time data acquisition and logical judgment, the system realizes fully automatic intelligent management from safety alarm linkage, on-demand ventilation to energy-saving operation, effectively ensuring safety, comfort and energy efficiency.

[0100] Example 2:

[0101] Please see Figure 1-6 A method for dynamically adjusting airflow and controlling air pressure balance in a pathology department, according to Example 1, includes the following steps:

[0102] S1. System Initialization and Self-Test: When the system is powered on, the control module runs a self-test program to check the status of each sensor, actuator, and communication line of the environmental monitoring module; initialize system parameters, including setting the target differential pressure value of the controlled room, the target indoor temperature and humidity, and the alarm thresholds for various air quality parameters; and set the initial frequency of the fresh air unit and exhaust fan to the reference frequency.

[0103] S2. Real-time data acquisition: The sensors in the environmental monitoring module continuously collect data, and the communication module performs protocol conversion and standardization to send real-time data information in a unified format to the control module. The data information includes air volume data, environmental data and equipment status data.

[0104] The air volume data includes the total fresh air volume (Q). 总新 ) and total exhaust volume (Q 总排 Environmental data includes controlled room pressure difference (ΔP), indoor temperature and humidity, fresh air temperature, exhaust air temperature, carbon dioxide concentration, formaldehyde concentration, xylene concentration, and VOC concentration; equipment status data includes the start / stop status of each ventilation device, filter devices, blockage alarm signals of medium-efficiency filters in fresh air units, and fire emergency stop signals.

[0105] S3. Decision-making and target instruction generation: Based on the real-time data from step S2 and combined with the built-in control program, the control module makes a comprehensive judgment and selects the appropriate operating mode to generate target instructions for each actuator.

[0106] S3.1 Static Operating Mode: All ventilation equipment is not started, and the system operates at a preset low load baseline. The control module continuously monitors the pressure difference ΔP between the inside and outside of the controlled room. If ΔP deviates from the target value, the frequency difference between the fresh air handling unit and the exhaust fan is adjusted to achieve balance. In static operating mode, the fresh air handling unit and the exhaust fan operate at the baseline frequency. All electric sealing dampers of the ventilation equipment are closed, and the electric opening regulating dampers of the ordinary exhaust duct are open with an opening of 100%.

[0107] Preferably, the reference frequency of the exhaust fan is 20Hz, and the reference frequency of the fresh air unit is 16Hz.

[0108] Preferably, when ΔP deviates from the target value, the frequency difference between the fresh air handling unit and the exhaust fan is adjusted by PID control. Let the target pressure difference value of the controlled room be P. 目标 The current actual pressure difference is P. 当前 If the deviation is e(t), then:

[0109] e(t) = P 目标 -P 当前 ;

[0110] When e(t) < 0, the actual negative pressure in the controlled room is insufficient;

[0111] When e(t) > 0, the negative pressure in the controlled room is too high.

[0112] Let the frequency correction be Δf, Δf = P 输出 +I 输出 +D 输出 , where P 输出 For the proportional element, I 输出 For the integration stage, D 输出 For the differential element:

[0113] P 输出 =Kp×e(t;

[0114] I 输出 =Ki×∫e(t)dt;

[0115] D 输出 =Kd×de(t) / dt;

[0116] Kp, Ki, and Kd are constants determined by optimizing and adjusting parameters on-site based on the dynamic characteristics of the controlled system and observing the system response curve.

[0117] Let the current frequency of the exhaust fan be f. 当前排风 The target frequency of the adjusted exhaust fan is f. 目标排风 The current frequency of the fresh air handling unit is f 当前新风 The target frequency of the adjusted fresh air handling unit is f. 目标新风 ,but:

[0118] When Δf > 0, increase the exhaust volume and decrease the fresh air volume, f 目标排风 =f 当前排风 +Δf,f 目标新风 =f 当前新风 -Δf×k, where k is a constant coefficient, k takes the value of 0.5~0.8, to ensure that the fresh air volume follows the change of the exhaust air volume and that the change of the fresh air volume is small, thereby maintaining a reasonable pressure difference.

[0119] When Δf < 0, reduce the exhaust volume and increase the fresh air volume. 目标排风 =f 当前排风 -Δf, f 目标新风 =f 当前新风 +Δf×k, where k is a constant coefficient, k takes the value of 0.5~0.8, to ensure that the fresh air volume follows the change of the exhaust air volume, and the change of the fresh air volume is small, so as to maintain a reasonable pressure difference.

[0120] S3.2 Dynamic operating mode: When ventilation equipment 16 is started or stopped, a status signal is sent to the main controller. The control module determines the number of exhaust fans (N) based on the number of currently activated ventilation equipment. 排风 The number of fresh air handling units is N 新风 Calculate and execute matching of the fresh air handling unit and exhaust fan to the target frequency f of the fresh air handling unit. 目标排风 Target frequency f of the exhaust fan 目标排风 To ensure that the total air volume of the system matches the operating requirements of the ventilation equipment, the control module opens the electric sealing air valves corresponding to the operating ventilation equipment and closes the electric sealing air valves corresponding to the non-operating ventilation equipment.

[0121] Preferred, f 目标排风 =5×N 排风 +20, f 目标新风 =4×N 新风 +16.

[0122] Preferably, the frequency of the fresh air handling unit is 80% of the frequency of the exhaust fan, thereby ensuring that the fresh air volume and exhaust air volume are matched and maintaining a slight negative pressure in the room (-5~-15Pa).

[0123] S3.3 Emergency Operating Mode:

[0124] Air quality emergency: When the air quality sensor group detects that the concentration of any harmful gas exceeds the set threshold, the control module immediately triggers the emergency linkage, the frequency of the fresh air unit and exhaust fan is forcibly set to the maximum value, all electric sealing air valves are switched to the open state, and the human-machine interface triggers an audible and visual alarm.

[0125] Fire emergency response: When the control module receives a fire emergency stop alarm monitoring signal through the DI interface, it immediately sets the frequency of the fresh air handling unit and the exhaust fan to 0Hz and stops the operation of the fresh air handling unit and the exhaust fan.

[0126] S4. Command Execution and System Status Feedback: The fan frequency target command generated by the control module is transmitted to the drivers of the fresh air handling unit and exhaust fan through the communication module. The environmental monitoring module senses changes in real time and feeds back data to form a closed-loop control.

[0127] S5. Continuous monitoring and alarm: The control module continuously runs a self-diagnostic program to monitor key system parameters. In case of filter blockage, equipment failure, or communication interruption, it triggers a system status alarm, which is displayed on the human-machine interface.

[0128] The control method provided by this invention achieves its core adjustment by controlling the frequency of the fresh air handling unit and the exhaust fan. The system has a direct response and clear logic. Through PID control, it achieves rapid stabilization and dynamic adjustment of the pressure difference in the controlled room. Based on the on / off status of the ventilation equipment, it matches the fan frequency with the air volume demand, significantly reducing energy consumption.

[0129] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A dynamic airflow regulation system for pediatric ward air pressure balance, characterized in that: The system includes a ventilation module, a control module, an environmental monitoring module, and a communication module. The environmental monitoring module includes several sensors that monitor the environment and equipment status. The output of the environmental monitoring module is electrically connected to the signal input of the communication module. The communication module converts signals from different protocols into a unified data format signal and outputs it to the control module. The control module generates target commands through a built-in control program, and the target commands are transmitted to the ventilation module via the communication module. The ventilation module includes a fresh air unit and an exhaust fan. The fresh air unit delivers outdoor airflow into the controlled room through fresh air ducts. Several [unclear - possibly referring to a specific type of ventilation system] are installed in the controlled room. A ventilation system is provided, with several ventilation devices connected to exhaust branch lines. These exhaust branch lines are connected to exhaust fans via exhaust ducts. A standard exhaust duct is laid within the controlled room, connecting to the exhaust duct, so that airflow within the controlled room sequentially passes through the standard exhaust duct, the exhaust duct, and the exhaust fan before being delivered outdoors. A fresh air valve is installed at the air inlet of the fresh air unit, and an electrically adjustable damper is installed on the standard exhaust duct. Electrically sealed dampers are installed at the air outlets of the ventilation devices. The ventilation module adjusts the total fresh air volume, total exhaust air volume, and allocates airflow to each ventilation device according to target instructions.

2. The pathology ward air pressure balance system with dynamic air volume adjustment according to claim 1, characterized in that: The end of the exhaust duct away from the ventilation equipment is connected to the exhaust fan via a filter device, and the airflow is filtered by the filter device and then discharged by the exhaust fan.

3. The pathology ward air pressure balance system with dynamic air volume adjustment according to claim 1, characterized in that: The system is also equipped with an air conditioner, which is connected to the fresh air unit. The total fresh air volume is equal to the sum of the air supply volume of the air conditioner and the air supply volume of the fresh air unit. The total exhaust volume is equal to the sum of the exhaust volume of the ordinary exhaust duct and the exhaust volume of the ventilation equipment.

4. A pathology ward air pressure balance system with dynamic air volume adjustment according to claim 3, characterized in that: The environmental monitoring module includes a fresh air temperature sensor and a fresh air volume sensor installed at the air inlet and air outlet of the fresh air unit, respectively, and an exhaust air volume sensor and an exhaust air temperature sensor installed sequentially on the exhaust duct.

5. A pathology ward air pressure balance system with dynamic air volume adjustment according to claim 4, characterized in that: The environmental monitoring module also includes a differential pressure sensor, an indoor temperature and humidity sensor group, and an air quality sensor group installed in the controlled room. The air quality sensor group includes several sensors for monitoring the concentration of harmful gases.

6. A pathology ward air pressure balance system with dynamic air volume adjustment according to claim 1, characterized in that: The control module includes a main controller, an expansion unit, and a device control input / output terminal, as well as a power supply component. The communication module includes a signal conversion and receiving unit and a signal conversion relay. The output terminal of the power supply component is electrically connected to the main controller, the expansion unit, and the device control input / output terminal. The main controller is connected to the expansion unit, the expansion unit is connected to the device control input / output terminal, and the device control input / output terminal is connected to the signal conversion and receiving unit and the signal conversion relay. The signal output by the environmental monitoring module is transmitted to the signal conversion and receiving unit. The target command generated by the control module is sent to the signal conversion relay through the device control input / output terminal. The output terminal of the signal conversion relay is connected to each actuator.

7. A method for dynamically adjusting airflow and controlling air pressure balance in a pathology department, characterized in that: The control method is based on a dynamic airflow adjustment system for pathology ward air pressure balance as described in any one of claims 1-6, and the control method includes the following steps: System initialization and self-test: The system starts up and the control module runs the self-test program; initializes system parameters, sets the target differential pressure value of the controlled room, the target indoor temperature and humidity, and the alarm thresholds for various air quality parameters, and sets the initial frequency of the fresh air unit and exhaust fan to the reference frequency; Real-time data acquisition: The sensors in the environmental monitoring module continuously collect data and send the real-time data information to the control module through the communication module. The data information includes air volume data, environmental data, and equipment status data. Decision-making and target instruction generation: The control module selects the operating mode, generates target instructions, and executes them based on real-time data information.

8. A method for dynamically adjusting airflow and controlling air pressure balance in a pathology department according to claim 7, characterized in that: The control module selects the operating mode based on real-time data information. The operating modes include the following modes: Static operating mode: All ventilation equipment is not started, and the system operates according to the preset low load baseline. In the static operating mode, the fresh air unit and exhaust fan initially operate at the reference frequency. The electric sealing air valves of the ventilation equipment are closed, and the electric opening regulating air valves of the ordinary exhaust duct are open at 100%. The control module continuously monitors the pressure difference ΔP between the inside and outside of the controlled room. If ΔP deviates from the target value, the frequency difference between the fresh air unit and the exhaust fan is adjusted to achieve balance. Dynamic operating mode: When ventilation equipment starts or stops, the corresponding status signal is sent to the main controller. The control module determines the number of exhaust fans (N) based on the number of currently activated ventilation equipment. 排风 The number of fresh air units is N 新风 Calculate and execute the target frequency of the fan, and match the target frequency f of the fresh air handling unit. 目标排风 The exhaust fan is matched with the target frequency f. 目标排风 To ensure that the total air volume of the system matches the operating requirements of the ventilation equipment, the control module opens the electric sealing air valves corresponding to the operating ventilation equipment and closes the electric sealing air valves corresponding to the non-operating ventilation equipment. Air quality emergency: When the air quality sensor group detects that the concentration of any harmful gas exceeds the set threshold, the control module immediately triggers the emergency linkage, the frequency of the fresh air unit and exhaust fan is forcibly set to the maximum value, all electric sealing air valves are switched to the open state, and the human-machine interface triggers an audible and visual alarm.

9. A method for dynamically adjusting airflow and controlling air pressure balance in a pathology department according to claim 8, characterized in that: When ΔP deviates from the target value, the frequency difference between the fresh air handling unit and the exhaust fan is adjusted by PID control. Let the target pressure difference value of the controlled room be P. 目标 The current actual pressure difference is P. 当前 If the deviation is e(t), then: e(t)=P 目标 -P 当前 ; When e(t) < 0, the actual negative pressure in the controlled room is insufficient; When e(t) > 0, the negative pressure in the controlled room is too high; Let the frequency correction be Δf, Δf = P 输出 +I 输出 +D 输出 The current frequency of the exhaust fan is f. 当前排风 The target frequency of the adjusted exhaust fan is f. 目标排风 The current frequency of the fresh air handling unit is f 当前新风 The target frequency of the adjusted fresh air handling unit is f. 目标新风 ,but: When Δf > 0, increase the exhaust volume and decrease the fresh air volume, f 目标排风 =f 当前排风 +Δf,f 目标新风 =f 当前新风 -Δf×k; When Δf < 0, reduce the exhaust volume and increase the fresh air volume. 目标排风 =f 当前排风 -Δf, f 目标新风 =f 当前新风 +Δf×k; where k takes values ​​from 0.5 to 0.

8.

10. A method for dynamically adjusting airflow and controlling air pressure balance in a pathology department according to claim 8, characterized in that: The algorithm for calculating and executing the target frequency of the wind turbine is as follows: f 目标排风 =5×N 排风 +20; f 目标新风 =4×N 新风 +16; The reference frequency of the exhaust fan is 20Hz, and the reference frequency of the fresh air unit is 16Hz.

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