Negative pressure ward air supply and exhaust energy-saving system and control method

Abstract

The invention relates to the technical field of energy-saving systems, in particular to a negative pressure ward air supply and exhaust energy-saving system and a control method, and the control method comprises the following steps: detecting the total current of a power supply loop for supplying power to a plurality of ward tail end exhaust fans; based on the detected total current and a preset load of an exhaust fan of a single ward, calculating the number of wards in which air exhaust is started currently, and generating a corresponding control voltage signal according to the number of the started wards; the variable-frequency controller is used for inputting the control voltage signal to the variable-frequency air feeder and the variable-frequency exhaust fan; the variable-frequency controller adjusts the operation frequencies of the variable-frequency air feeder and the variable-frequency exhaust fan according to the control voltage signal, and adjusts the air supply amount and the air exhaust amount in proportion; the air volume is proportional to the operation frequency. According to the invention, electrical parameter detection and fluid equipment control are combined, intelligent on-demand adjustment of the negative pressure ward ventilation system is realized through a simple and reliable hardware scheme, and the problem of overhigh energy consumption of a traditional system is solved while the safety of a medical environment is strictly guaranteed.

Description

Technical Field

[0001] This invention relates to an energy-saving system and control method for supplying and exhausting air in negative pressure wards, and particularly to an energy-saving system and control method for supplying and exhausting air in negative pressure wards, belonging to the field of energy-saving system technology. Background Technology

[0002] Negative pressure isolation wards are key medical facilities for treating patients with respiratory infectious diseases. Their core requirement is to prevent contaminated air from leaking out by maintaining a pressure inside the ward that is lower than that of the external environment. To this end, the air supply and exhaust systems need to be operated continuously to form a stable directional airflow. In traditional designs, a centralized supply and exhaust ventilation system often serves multiple wards. In order to ensure that the pressure difference and air exchange rate requirements can be met at any time under the most unfavorable conditions (such as when all wards are in use at the same time), the fans are usually selected based on the maximum load and run at full load at the industrial frequency for a long time. However, in actual use, not all wards are always fully occupied. Traditional systems still operate at maximum airflow when some wards are idle, resulting in a large amount of electricity being wasted on "over-ventilation" and extremely high energy consumption. This not only increases the hospital's operating costs but also contradicts the concept of building a green hospital. Therefore, it is urgent to improve a negative pressure ward air supply and exhaust energy-saving system and control method to solve the above-mentioned problems. Summary of the Invention

[0003] The purpose of this invention is to provide an energy-saving ventilation system and control method for negative pressure wards, in order to solve the problem that in actual use, not all wards are always fully occupied, and traditional systems still operate at maximum air volume when some wards are idle, resulting in a large amount of electricity being wasted on "over-ventilation" and extremely high operating energy consumption. This not only increases the hospital's operating costs, but also contradicts the concept of building a green hospital.

[0004] To achieve the above objectives, the present invention provides the following technical solution: A negative pressure ward air supply and exhaust energy-saving system and control method, comprising the following steps: Step 1: Detect the total current of the power supply circuits for the terminal exhaust fans in multiple wards. ; Step 2: Based on the detected total current Given the preset exhaust fan load P for a single ward, calculate the number N of wards currently with exhaust fans activated. The calculation formula is as follows: ; Step 3: Generate a corresponding control voltage signal based on the number N of open wards; Step 4: Input the control voltage signal to the frequency converter controller of the frequency converter fan and the frequency converter exhaust fan; Step 5: The frequency converter adjusts the operating frequency f of the frequency converter blower and the frequency converter exhaust fan according to the control voltage signal, and adjusts their air supply volume and exhaust volume Q proportionally; The air volume Q is proportional to the operating frequency f.

[0005] Preferably, step 1 further includes a signal conversion step: converting the total current in the range of 0 to 12P / 220 amperes using a current transmitter. Linearly converted to an analog voltage signal from 0 to 10V.

[0006] Preferably, in step 3, the step of generating the control voltage signal includes: inputting the analog voltage signal to a signal conditioning circuit for proportional calculation, and outputting the adjusted voltage signal as the control voltage signal.

[0007] Preferably, the signal conditioning circuit is a non-inverting proportional operational circuit, and its output voltage... This is achieved by adjusting the feedback resistor. and input resistance The value is used to correct signal errors.

[0008] Preferably, by setting the feedback resistor , making .

[0009] Preferably, the control voltage signal of 0 to 10V received by the frequency converter controller controls the frequency converter blower and the frequency converter exhaust fan to operate within the range of 0 to the rated frequency.

[0010] Preferably, the relationship between the rotational speed n of the variable frequency blower and the variable frequency exhaust fan and the operating frequency f satisfies ,in The number of pole pairs of the motor is denoted by ; the air volume Q is proportional to the rotational speed n.

[0011] Preferably, it includes a supply and exhaust ventilation system serving multiple wards; variable frequency supply fans and variable frequency exhaust fans; and a current detection unit for detecting the total current of the power supply circuit that powers the terminal exhaust fans of the multiple wards. The current detection unit includes a current transmitter; a control unit configured to perform the control method as described in any one of claims 1-7; a frequency converter for adjusting the operating frequency of the frequency converter blower and the frequency converter exhaust fan according to the control signal generated by the control unit; and a signal conditioning circuit connected to the current detection unit and the frequency converter.

[0012] This invention has at least the following beneficial effects: This invention combines electrical parameter detection with fluid equipment control, and with a simple and reliable hardware solution, realizes intelligent on-demand adjustment of the ventilation system in negative pressure wards. While strictly ensuring the safety of the medical environment, it solves the problem of excessive energy consumption in traditional systems, and has outstanding economic value and social benefits. Attached Figure Description

[0013] Figure 1 This is a block diagram of an energy-saving air supply and exhaust system for a negative pressure ward according to the present invention; Figure 2 This is a flowchart of a control method for an energy-saving supply and exhaust ventilation system in a negative pressure ward according to the present invention. Detailed Implementation

[0014] The following will describe in detail the implementation of this application with reference to the accompanying drawings and embodiments, so that the implementation process of how this application uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0015] like Figure 1-2 As shown in the figure, this embodiment provides an energy-saving supply and exhaust ventilation system and control method for negative pressure wards, which includes the following steps: Step 1: Detect the total current of the power supply circuits for the terminal exhaust fans in multiple wards. Step 2: Based on the detected total current Given the preset exhaust fan load P for a single ward, calculate the number N of wards currently with exhaust fans activated. The calculation formula is as follows: Step 3: Generate a corresponding control voltage signal based on the number of wards N opened; Step 4: Input the control voltage signal to the frequency converter controller of the frequency converter supply fan and the frequency converter exhaust fan; Step 5: The frequency converter controller adjusts the operating frequency f of the frequency converter supply fan and the frequency converter exhaust fan according to the control voltage signal, and adjusts their air supply volume and exhaust volume Q proportionally; the air volume Q is proportional to the operating frequency f.

[0016] As a further implementation of this scheme, step 1 further includes a signal conversion step: converting the total current in the range of 0 to 12P / 220 Amperes using a current transmitter. This current transmitter linearly converts high-voltage current signals to 0 to 10V analog voltage signals, achieving precise linear conversion from high-voltage current signals to standard, safe low-voltage analog signals. This provides a stable, reliable, and easy-to-process input signal for subsequent control circuits, enhancing the system's anti-interference capability and measurement accuracy. As a further implementation of this scheme, in step 3, the step of generating the control voltage signal includes: inputting the analog voltage signal to the signal conditioning circuit for proportional calculation, and outputting the adjusted voltage signal as the control voltage signal. The signal conditioning circuit performs precise proportional calculation and amplification on the voltage signal, which can flexibly adapt to the input voltage range requirements of different frequency converters and compensate for losses during signal transmission to ensure the accuracy of the final control signal. As a further implementation of this scheme, the signal conditioning circuit is a non-inverting proportional operational circuit, and its output voltage... This is achieved by adjusting the feedback resistor. and input resistance The values ​​of Rf and R1 are used to correct signal errors. A non-inverting proportional operational circuit is adopted, which has a simple structure and stable performance. By adjusting the resistance values ​​of Rf and R1, the system errors (such as transmitter errors and line attenuation) of the entire detection and control link can be easily calibrated and compensated, thereby improving the overall control accuracy. As a further implementation of this solution, wherein: by setting a feedback resistor , making The circuit is configured as a voltage follower, primarily serving as an isolation and buffer when signal amplification is not required. This effectively reduces the output load of the preceding signal source, preventing signal attenuation or distortion during transmission due to load changes, thus ensuring signal fidelity. As a further implementation of this scheme, the variable frequency controller receives a control voltage signal of 0 to 10V, which corresponds to the control of the variable frequency supply fan and the variable frequency exhaust fan to operate within the range of 0 to the rated frequency. This clarifies the linear correspondence between the control signal and the fan output, and realizes continuous, smooth and precise proportional control of the fan speed (and air volume), avoiding step changes, making the system response more stable and the energy-saving adjustment more refined. As a further implementation of this scheme, the relationship between the rotational speed n of the variable frequency supply fan and the variable frequency exhaust fan and the operating frequency f satisfies the following: ,in The number of pole pairs of the motor is given; the air volume Q is proportional to the speed n. From the perspective of motor principle, the direct control relationship between frequency f and speed n is clarified, and the proportional relationship between speed and air volume Q is also established, laying the core theoretical foundation of the entire control method and ensuring the scientificity and effectiveness of achieving precise air volume control by adjusting the frequency. As a further implementation of this solution, it includes: a supply and exhaust ventilation system serving multiple wards; variable frequency supply fans and variable frequency exhaust fans; and a current detection unit for detecting the total current of the power supply circuit powering the terminal exhaust fans in multiple wards. The current detection unit includes a current transmitter (using a current transmitter as the detection core, it can safely and accurately convert the main circuit current signal into a standard control signal, and is a key component for realizing non-invasive, high-reliability load quantity detection); a control unit configured to execute the control method as described in any one of claims 1-7; a frequency converter for adjusting the operating frequency of the frequency converter supply fan and the frequency converter exhaust fan according to the control signal generated by the control unit; and a signal conditioning circuit connected to the current detection unit and the frequency converter (adding an independent signal conditioning circuit improves the modularity and flexibility of the system design; this circuit can optimize the detection signal before sending it to the frequency converter, improving the stability and reliability of the entire control loop); the system fully integrates all the key hardware and logic of the control method, and can automatically and in real time dynamically adjust the total supply and exhaust air volume according to the actual number of patients in the ward, accurately matching the fan energy consumption with the load demand, thereby achieving significant energy saving while ensuring the safety of the negative pressure environment.

[0017] If certain terms are used in the specification and claims to refer to specific components, those skilled in the art will understand that hardware manufacturers may use different names to refer to the same component. This specification and claims do not distinguish components based on differences in name, but rather on differences in function. The term "comprising" as used throughout the specification and claims is an open-ended term and should be interpreted as "comprising but not limited to." "Approximately" means that within an acceptable margin of error, those skilled in the art can solve the technical problem and substantially achieve the technical effect within a certain margin of error.

[0018] It should be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a product or system comprising a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a product or system. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the product or system that includes that element.

[0019] The foregoing description illustrates and describes several preferred embodiments of the present invention. However, as previously stated, it should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the inventive concept described herein through the foregoing teachings or techniques or knowledge in related fields. Any modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.

Claims

1. A control method for an energy-saving supply and exhaust ventilation system in a negative pressure ward, characterized in that, Includes the following steps: Step 1: Detect the total current of the power supply circuits for the terminal exhaust fans in multiple wards. ; Step 2: Based on the detected total current Given the preset exhaust fan load P for a single ward, calculate the number N of wards currently with exhaust fans activated. The calculation formula is as follows: ; Step 3: Generate a corresponding control voltage signal based on the number N of open wards; Step 4: Input the control voltage signal to the frequency converter controller of the frequency converter fan and the frequency converter exhaust fan; Step 5: The frequency converter adjusts the operating frequency f of the frequency converter blower and the frequency converter exhaust fan according to the control voltage signal, and adjusts their air supply volume and exhaust volume Q proportionally; The air volume Q is proportional to the operating frequency f.

2. The control method for an energy-saving supply and exhaust ventilation system in a negative pressure ward according to claim 1, characterized in that: Step 1 also includes a signal conversion step: converting the total current in the range of 0 to 12P / 220 Amperes using a current transmitter. Linearly converted to an analog voltage signal from 0 to 10V.

3. The control method for an energy-saving supply and exhaust ventilation system in a negative pressure ward according to claim 1, characterized in that: In step 3, the step of generating the control voltage signal includes: inputting the analog voltage signal to the signal conditioning circuit for proportional calculation, and outputting the adjusted voltage signal as the control voltage signal.

4. The control method for an energy-saving supply and exhaust ventilation system in a negative pressure ward according to claim 1, characterized in that: The signal conditioning circuit is a non-inverting proportional operational circuit, and its output voltage This is achieved by adjusting the feedback resistor. and input resistance The value is used to correct signal errors.

5. The control method for an energy-saving supply and exhaust ventilation system in a negative pressure ward according to claim 1, characterized in that: By setting the feedback resistor , making .

6. The control method for an energy-saving supply and exhaust ventilation system in a negative pressure ward according to claim 1, characterized in that: The frequency converter receives a control voltage signal of 0 to 10V, which corresponds to controlling the frequency converter blower and the frequency converter exhaust fan to operate within the range of 0 to the rated frequency.

7. The control method for an energy-saving supply and exhaust ventilation system in a negative pressure ward according to claim 1, characterized in that: The relationship between the rotational speed n of the variable frequency blower and the operating frequency f satisfies ,in The number of pole pairs of the motor is denoted by ; the air volume Q is proportional to the rotational speed n.

8. The energy-saving supply and exhaust ventilation system for negative pressure wards according to claim 1, characterized in that: This includes a supply and exhaust ventilation system that serves multiple wards; Variable frequency blowers and variable frequency exhaust fans; The current detection unit is used to detect the total current of the power supply circuit that supplies power to the multiple ward terminal exhaust fans. The current detection unit includes a current transmitter; The control unit is configured to perform the control method as described in any one of claims 1-7; A frequency converter is used to adjust the operating frequency of the frequency converter blower and the frequency converter exhaust fan according to the control signal generated by the control unit. It also includes a signal conditioning circuit connected to the current detection unit and the frequency converter.

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