CN108562016B - Total air volume control method and device for multi-terminal centralized air exhaust - Google Patents

Total air volume control method and device for multi-terminal centralized air exhaust Download PDF

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CN108562016B
CN108562016B CN201810298710.5A CN201810298710A CN108562016B CN 108562016 B CN108562016 B CN 108562016B CN 201810298710 A CN201810298710 A CN 201810298710A CN 108562016 B CN108562016 B CN 108562016B
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CN108562016A (en
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高军
侯玉梅
曹昌盛
柳国栋
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Tongji University
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/0001—Control or safety arrangements for ventilation
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/62—Control or safety arrangements characterised by the type of control or by internal processing, e.g. using fuzzy logic, adaptive control or estimation of values
    • F24F11/63—Electronic processing
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/70—Control systems characterised by their outputs; Constructional details thereof
    • F24F11/72—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure
    • F24F11/74—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure for controlling air flow rate or air velocity
    • F24F11/77—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure for controlling air flow rate or air velocity by controlling the speed of ventilators
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
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Abstract

In a multi-terminal centralized exhaust system, monitoring multiple terminals to obtain operation air demand, calculating the worst hydraulic power failure dispatching to correct the operation air demand to obtain the actual operation air discharge of the system, and controlling the operation of a fan according to the operation air demand. The invention also discloses a multi-terminal centralized exhaust control device, which comprises one or more variable frequency fans (1), a hydraulic power dispatching calculator (2) and a multi-terminal monitoring system (3); the one or more variable frequency fans are connected in parallel, and the hydraulic power dispatching loss calculator (2) is connected with the multi-terminal monitoring system (3); the invention can be used for solving the problem of variable air volume operation regulation and control in a multi-terminal centralized exhaust system. The invention overcomes the defects of complex system, high energy consumption and the like of the constant static pressure and variable static pressure control method in the prior art.

Description

Total air volume control method and device for multi-terminal centralized air exhaust
Technical Field
The invention belongs to the technical field of ventilation control, and relates to a total air volume control method, in particular to a total air volume control method and a total air volume control device for a multi-tail-end centralized exhaust system.
Background
The traditional control method of the total air volume of the ventilation system is a fixed static pressure method and a variable static pressure method. The static pressure method is simple to control, but the energy consumption of the fan is high, and most of the tail end valves are in a small state, so that the serious noise problem is caused correspondingly; the variable static pressure method has complex algorithm and difficult realization, and products provided by control companies generally do not provide the variable static pressure control algorithm, so that control personnel are required to program and debug on site, and the workload is large.
Disclosure of Invention
The invention aims to provide a simple total air volume control method and a simple total air volume control device, which can overcome the defects of complex system, high energy consumption and the like of a constant static pressure and variable static pressure control method in the prior art aiming at a multi-terminal centralized exhaust system.
In order to achieve the purpose, the technical scheme adopted by the invention has the following beneficial effects:
in a multi-terminal centralized exhaust system, multiple terminals are monitored to obtain the operation air demand, the worst hydraulic power failure dispatching is calculated to correct the operation air demand to obtain the actual operation air exhaust volume of the system, and the operation of a fan is controlled according to the actual operation air exhaust volume.
Further, the method comprises: solving the worst hydraulic power failure rate by an off-line method according to the opening rate calculated by the multi-terminal monitoring system, and calculating the hydraulic working conditions of the exhaust pipe network system under different operation opening rates in advance to form a single-value corresponding relation between the worst hydraulic power failure rate and the operation opening rate; in addition, according to the performance matching of the fans, the corresponding relation between the air quantity and the rotating speed of the fans can be obtained, the obtained worst hydraulic power failure scheduling is used for correcting the ideal operation air quantity, and then the fan operation frequency is obtained according to the corresponding relation between the air quantity and the rotating speed of the fans.
The total air discharge quantity is obtained by multiplying the calculated opening rate by the designed air discharge quantity of each tail end; correcting the air discharge amount by the worst scheduling to obtain the actual operation air discharge amount of the system; and finally, calculating the running frequency of the fan according to the air exhaust amount, and controlling the variable-frequency running of the fan according to the running frequency.
The designed air volume of each tail end of the multi-tail-end centralized exhaust system is consistent, and each tail end has the operation requirement of random opening and closing; in the system operation process, if the tail end is monitored to be opened and closed, the operation opening rate is calculated according to the following formula:
Figure BDA0001617299170000011
and further calculating the worst hydraulic power failure rate according to the calculated opening rate result.
If the opening rate is not changed, the fan keeps the original rotating speed to operate, and if the opening rate is changed, the fan needs to correspondingly operate in a variable frequency mode; in a ventilation pipeline system, if the hydraulic stability of the system is equal to 1, the total impedance of the system is unchanged, and the total air quantity required by the system and the rotating speed of a fan are in a proportional relation through hydraulic calculation and fan performance matching in advance:
Figure BDA0001617299170000021
the relation between the operating state and the design state is as follows:
Figure BDA0001617299170000022
according to the relation between the rotating speed and the frequency:
Figure BDA0001617299170000023
calculating the running frequency f of the fan under the corresponding working conditionOperation of；
Wherein G is1Representing the system air volume before frequency conversion; g2Representing the system air volume after frequency conversion; n is a radical of1Representing the rotating speed of the fan before frequency conversion; n is a radical of2Representing the rotating speed of the fan after frequency conversion;
Gdesign ofRepresenting the system air volume under the design working condition; gOperation ofRepresenting the system air volume under the operation condition; n is a radical ofDesign ofRepresenting the rotating speed of the fan under the design working condition; n is a radical ofOperation ofIndicating the rotating speed of the fan under the operating condition; f. ofOperation ofRepresenting the fan frequency under the operating condition; p represents the fan power.
If the hydraulic stability of the multi-terminal system is not 1, and each opening rate also covers the combined information of a plurality of opening positions, namely a plurality of working conditions exist under one opening rate; under each working condition, different hydraulic power failure scheduling x at each tail end is set as the actual operation flow rate/the flow rate required by design; and calculating the worst hydraulic power failure rate at each opening rate, wherein the worst hydraulic power failure rate is the safety compensation coefficient 1/x at the corresponding opening rate.
Under a certain opening rate, analyzing the hydraulic working condition of a pipe network, wherein the total resistance of the system is the largest when the tail end positions are all gathered at the far end, and the sum of the total air flow of the system under the working condition is the smallest under the same fan frequency; according to the hydraulic power dispatching minimum value x of each tail end under the situationminThe result is used as the calculation basis of safety compensation under the corresponding opening rate, and the running rotating speed of the fan is further corrected to be
Figure BDA0001617299170000024
Frequency is corrected to
Figure BDA0001617299170000025
Further gathering the tail end position to the near end and dispersing the tail end position to x under the working condition of two endsminThe results are also pre-calculated and then x for three conditionsminTaking the minimum value as the final basis of the frequency conversion of the fan; wherein N isOperation ofIndicating the rotating speed of the fan under the operating condition; f. ofOperation ofIndicating the fan frequency under operating conditions.
The multi-terminal centralized air exhaust control device for realizing the multi-terminal centralized air exhaust total air volume control method at least comprises a variable frequency fan, a hydraulic power failure dispatching calculator and a multi-terminal monitoring system, wherein the operating frequency of the fan is determined according to the operating air volume demand fed back by the multi-terminal monitoring system and the worst hydraulic power imbalance value provided by the hydraulic power failure dispatching calculator.
Further, the system comprises one or more variable frequency fans, a worst hydraulic power failure scheduling calculator, a multi-tail-end monitoring system, a plurality of exhaust system branch pipes, a tail-end opening and closing valve and an exhaust system main pipe; the variable frequency fan is connected with the main exhaust system pipe to provide exhaust required by the system, the main exhaust system pipe is provided with a plurality of exhaust system branch pipes, each exhaust system branch pipe is provided with a tail end opening and closing valve, the multi-tail end monitoring system is connected with the tail end opening and closing valves arranged on the exhaust system branch pipes to obtain monitoring signals, the worst hydraulic power failure scheduling calculator is connected with the multi-tail end monitoring system to obtain the opening rate of the system, the required operating frequency of the system fan is fed back, and the worst hydraulic power failure scheduling calculator is connected with the variable frequency fan to transmit the current required operating frequency, so that the total air volume control of the system is achieved.
The fan is driven by a direct current or alternating current motor; the hydraulic power dispatching loss calculator is used for finishing calculation of the worst hydraulic power dispatching loss and the running frequency of the fan.
The multi-terminal monitoring system transmits information in a wired communication mode, and the total opening rate is calculated by monitoring the opening or closing condition of each terminal;
preferably, the communication line of the multi-terminal monitoring system is arranged in the sleeve and fixedly installed along the inner wall and the outer wall of the air pipe of the exhaust system.
In the multi-terminal centralized exhaust system, the fan can be driven by a direct current or alternating current motor, the running air demand is obtained through the feedback of the multi-terminal monitoring system, and the worst hydraulic power dispatching loss value provided by the hydraulic power dispatching loss calculator corrects the running air demand. The simple total air volume control method has the characteristic of no air volume monitoring, and is simple, convenient, stable and reliable to control.
In some embodiments, the multi-terminal monitoring system is transmitted by wired communication, and the total opening rate is calculated by monitoring the opening or closing of each terminal; when the multi-terminal monitoring system monitors the opening and closing conditions of each terminal, the position information corresponding to each terminal does not need to be monitored; the communication line can be arranged in the sleeve and fixedly arranged along the inner wall and the outer wall of the air duct. The method has the advantages of rapid, stable and reliable signal transmission and capability of ensuring rapid response of the system.
In the simple total air volume control method of the multi-terminal centralized exhaust system, a hydraulic power dispatching loss calculator can calculate the worst hydraulic power dispatching loss and the running frequency of a fan, and the calculation method comprises the following steps: hydraulic working conditions of the exhaust pipe network system under different opening rates are calculated in advance to form a single-value corresponding relation between the worst hydraulic power failure rate x and the opening rate, namely one opening rate corresponds to the worst hydraulic power failure rate x, and the worst hydraulic power failure rate x is used as the running frequency f of the fanOperation ofThe correction coefficient of (2); as shown in equations (1), (2) and (3).
Figure BDA0001617299170000031
Figure BDA0001617299170000032
Figure BDA0001617299170000033
Wherein x represents the worst scheduling loss under a certain working condition; gDesign ofRepresenting the system air volume under the design working condition; gOperation ofRepresenting the system air volume under the operation condition; n is a radical ofDesign ofRepresenting the rotating speed of the fan under the design working condition; n is a radical ofOperation ofIndicating the rotating speed of the fan under the operating condition; f. ofOperation ofRepresenting the fan frequency under the operating condition; f. ofRunning, correctingRepresenting the actual operating frequency of the fan corrected by the worst scheduling loss; p represents the fan power, related to the fan parameters.
The worst hydraulic power failure rate is calculated in advance, the worst system failure rate under each hydraulic power failure rate needs to be calculated, namely the opening rate needs to be calculated from 0 to 1. Because each opening rate corresponds to a plurality of opening positions, and the workload is heavy, the invention provides that only the opening position is calculated to be positioned at the far fan end under each opening rate, and the minimum hydraulic power failure rate of the working condition is the worst hydraulic power failure rate under the opening rate.
The method has the advantages that the worst hydraulic power dispatching failure rate and the operation frequency corresponding to each opening rate are obtained through pre-calculation, and complicated hydraulic calculation of a pipe network in actual operation can be avoided.
In the simple total air volume control method of the multi-terminal centralized exhaust system, the total air volume is obtained by multiplying the opening rate calculated by the multi-terminal monitoring system by the designed air volume of each terminal; correcting the air discharge amount by the worst scheduling to obtain the actual operation air discharge amount of the system; and finally, calculating the running frequency of the fan according to the air exhaust amount, so that the fan runs in a variable frequency mode. The method has the advantages that the traditional complex control mode of static pressure fixing and static pressure changing is abandoned, and a simple single-value function control logic of the opening rate → the worst hydraulic power failure scheduling → the air quantity correction → the fan rotating speed → the fan operating frequency is formed, so that the simple air quantity changing requirement of the system can be quickly responded.
The calculation method of the worst scheduling loss is as follows: hydraulic working conditions of the exhaust pipe network system under different operation opening rates are calculated in advance, a simple single-value corresponding relation between the worst hydraulic power loss scheduling and the operation opening rate is formed, and the simple single-value corresponding relation is used as a simple and reliable calculation basis for hydraulic power loss scheduling off-line, so that the core of the simple total air volume control method technology is formed; and then the required operating frequency of the fan can be obtained by substituting according to the opening rate calculated by the multi-terminal monitoring system, so that the method is an off-line calculation method.
The method for calculating the running frequency of the fan comprises the following steps: the air quantity and the operation frequency of the exhaust pipe network system under the design working condition are also pre-calculated, and the corresponding relation between the air quantity and the rotating speed of the fan can be obtained according to the performance matching of the fan; then, the worst hydraulic power failure scheduling obtained in the last step is used for correcting the ideal air volume; and finally, calculating the running frequency of the fan according to the corresponding relation between the air quantity and the rotating speed of the fan.
Drawings
Fig. 1 is a schematic connection diagram of each device of a simple total air volume control system in an embodiment of the present invention.
Reference numerals: the system comprises a variable frequency fan 1, a worst hydraulic power failure scheduling calculator 2, a multi-tail-end monitoring system 3, an exhaust system branch pipe 4, a tail-end opening and closing valve 5 and an exhaust system main pipe 6.
Detailed Description
The invention will be described in more detail below with reference to an embodiment shown in the drawings.
As shown in fig. 1, the simple total air volume control method for a multi-terminal centralized exhaust system provided by the present invention has a schematic connection of related devices, and includes one or more variable frequency fans 1, a worst hydraulic power loss scheduling calculator 2, a multi-terminal monitoring system 3, a plurality of exhaust system branch pipes 4, a terminal opening and closing valve 5, and an exhaust system main pipe 6.
The worst hydraulic power failure rate calculator firstly needs to pass the pre-test to obtain the hydraulic power failure rates of the system under different opening rates, so as to obtain the minimum and worst hydraulic power failure rate, for example, the system corresponding to the embodiment calculates the corresponding results shown in the following table:
TABLE 1-2 calculation of worst hydraulic power loss scheduling
Figure BDA0001617299170000051
Programming the turn-on rate and worst-case schedulingThe calculation module applies the formulas (2), (3) and (4) after the hydraulic power descheduling calculator receives the current opening rate of the system, and combines the calculation result x of the most unfavorable hydraulic power descheduling which is implanted in advanceminAnd obtaining the running frequency of the fan under the corresponding opening rate.
The multi-terminal monitoring system consists of three parts, namely a sensor positioned at each terminal, a transmission lead for connecting the sensor and a control system, the control system and the like, and the circuit and the mechanical structure of the multi-terminal monitoring system are obvious.
The variable frequency fan 1 is connected with an exhaust system main pipe 6 to provide exhaust required by the system, a plurality of exhaust system branch pipes 4 are arranged on the exhaust system main pipe 6, a tail end opening and closing valve 5 is arranged on each exhaust system branch pipe 4, a multi-tail end monitoring system 3 is connected with the tail end opening and closing valves 5 arranged on the exhaust system branch pipes 4 to obtain monitoring signals, a worst hydraulic power failure scheduling calculator 2 is connected with the multi-tail end monitoring system 3 to obtain the opening rate of the system, the required operating frequency of the system fan is fed back, and the worst hydraulic power failure scheduling calculator 2 is connected with the variable frequency fan 1 to transmit the current required operating frequency, so that the total air volume control of the system is achieved.
The multi-tail-end centralized exhaust system in the embodiment can be a multi-tail-end exhaust system in any occasion, the designed air volume of each tail end is consistent, and each tail end has the operation requirement of random opening and closing. For example, a centralized collection system for waste gas of a plurality of devices in a vulcanization workshop, a multi-station centralized smoke exhaust system in a welding workshop, a centralized exhaust system of a multi-exhaust cabinet in a laboratory and the like. In the system operation process, if the tail end is opened and closed and changed, a multi-tail-end monitoring system monitors and counts opening and closing signals of a tail end valve, equipment and the like, after the monitoring signals are obtained, the operation opening rate is calculated, the opening rate result is transmitted to a hydraulic power failure scheduling calculator, and the calculation method of the opening rate is as follows:
Figure BDA0001617299170000052
if the opening rate is not changed, the fan keeps the original rotating speed to operate, and if the opening rate is changed, the fan needs corresponding frequency conversion operation. In a ventilation pipeline system, assuming that the hydraulic stability of the system is equal to 1, the total impedance of the system is unchanged, and the total air quantity required by the system and the rotating speed of a fan are in a direct proportion relationship through hydraulic calculation and fan performance matching in advance:
Figure BDA0001617299170000061
wherein G is1Representing the system air volume before frequency conversion; g2Representing the system air volume after frequency conversion; n is a radical of1Representing the rotating speed of the fan before frequency conversion; n is a radical of2And expressing the rotating speed of the fan after frequency conversion.
The relationship between the operating state and the design state can be obtained as follows:
Figure BDA0001617299170000062
and then according to the relation between the rotating speed and the frequency:
Figure BDA0001617299170000063
the operating frequency f of the fan under the corresponding working condition can be obtainedOperation of。
Wherein x represents the worst scheduling loss under a certain working condition; gDesign ofRepresenting the system air volume under the design working condition; gOperation ofRepresenting the system air volume under the operation condition; n is a radical ofDesign ofRepresenting the rotating speed of the fan under the design working condition; n is a radical ofOperation ofIndicating the rotating speed of the fan under the operating condition; f. ofOperation ofRepresenting the fan frequency under the operating condition; f. ofRunning, correctingRepresenting the actual operating frequency of the fan corrected by the worst scheduling loss; p represents the fan power, related to the fan parameters.
Thus, the total air volume and the fan running frequency at the current moment can be determined by the running opening rate obtained by the multi-terminal monitoring system; however, the hydraulic stability of the multi-terminal system cannot be 1, and the combined information of many opening positions is covered at each opening rate, that is, there are many working conditions at one opening rate, and each terminal has different hydraulic power failure schedule x (actual operation flow/flow required by design) at each working condition. And calculating the worst hydraulic power loss schedule (namely the minimum value of the hydraulic imbalance value) at each opening rate, wherein the worst hydraulic power loss schedule is the safe compensation coefficient 1/x at the corresponding opening rate.
According to hydraulic working condition analysis, under a certain opening rate (simply, the ratio of the number of opened tail ends to the number of all tail ends of certain tail end opening and closing valves in an opening state), three limit situations of tail end positions are considered, wherein the opened tail ends are all gathered at the near fan end, the opened tail ends are all gathered at the far fan end, and the opened tail ends are dispersed at the far and near ends. For analysis of hydraulic working conditions of a pipe network, the total resistance of the system is the largest when all the air flow is gathered at a far end, and under the same fan frequency, the total air flow of the system is the smallest under the working conditions, namely the actual total air flow of the system exhausted from each opened tail end is the smallest. Therefore, the invention proposes to use the minimum value x of the hydraulic power loss schedule at each end in the sceneminThe result is used as the calculation basis of the safety compensation under the corresponding opening rate, and the running rotating speed of the fan is corrected to
Figure BDA0001617299170000064
Frequency is corrected to
Figure BDA0001617299170000065
Considering the reliability of the simple total wind control method, all the x are gathered at the near end and dispersed under the working conditions of two endsminThe results are also pre-calculated and then x for three conditionsminAnd taking the minimum value as the final basis of the frequency conversion of the fan.
The system adopts a main air pipe with equal section, the size is 350mm × 350mm, every two branch pipes are spaced by 3m, the length of each branch pipe is 1.5m, the section shape is square, the side length is 150mm, in this example, the design air quantity of a single branch pipe is 400m3The design opening rate is 0.6. At an opening rate of 0.6 and is openedUnder the working condition that the positions are uniformly distributed, the air exhaust volume of each branch pipe is ensured to be uniformly distributed by designing the flow guide component. According to the design working condition, the total resistance of the system under the design air volume is calculated to be 200Pa, and the air volume is 2400m3H is used as the reference value. The model of the fan is selected according to the design working condition, the frequency of the fan can be changed within 15-100Hz, and the frequency of the fan corresponding to the design working condition is 35 Hz.
In this embodiment, the opening rate is 0.4, and when the opening rate is 0.4, the total air volume of the system corresponding to the operation is 400m3/h×4＝1600m3H is used as the reference value. In the experimental test, three limit scenes of the tail end position are considered, the 1#, 2#, 3#, 4# air ports are firstly opened, other air ports are closed, and the running rotating speed of the fan is adjusted to be
Figure BDA0001617299170000071
The corresponding fan operating frequency is 23 Hz; and measuring the air volume of each opening branch by using a pitot tube, a micro-pressure meter and the like, and recording a test result. And similarly, opening the 7#, 8#, 9#, and 10# branches, closing other branches, maintaining the rotating speed of the fan, and measuring and recording the air volume of the corresponding opened branch. Finally, the air volume under the working conditions of opening the 4#, 5#, 6#, and 7# branches is tested, and the result is processed as the following table 1. According to the test result, under the combination of three different opening positions, a most unfavorable hydraulic power failure schedule x can be obtainedmin0.89. Thereby serving as a correction factor for the operation of the fan, namely the operation speed N when the fan is at the opening rate of 0.4Operation of/xminSince the fan operating speed is in direct proportion to the frequency, the frequency correction is 23Hz/0.89 to 26 Hz.
TABLE 1 test results for 0.4 opening ratio
Figure BDA0001617299170000072
Referring to the above process, the correction coefficients at opening ratios of 0.1, 0.2, 0.3, 0.5, 0.7, 0.8, 0.9, 1 were found, and the results are shown in table 2.
TABLE 2 Fan operating frequency for different opening ratios
Figure BDA0001617299170000081
And writing the fan operation frequency result corresponding to each opening rate listed in the table 2 into a fan control module, and detecting the tail end opening rate to give the fan operation frequency and ensure the air exhaust volume design of each branch, so that the simple total air volume control of the system is completed.
The embodiments described above are intended to facilitate one of ordinary skill in the art in understanding and using the present invention. It will be readily apparent to those skilled in the art that various modifications to these embodiments may be made, and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present invention is not limited to the embodiments described herein, and those skilled in the art should make improvements and modifications within the scope of the present invention based on the disclosure of the present invention.

Claims (9)

1. A total air volume control method for multi-tail-end centralized air exhaust is characterized in that: in the multi-tail-end centralized exhaust system, monitoring the multiple tail ends to obtain the operation air demand, calculating the worst hydraulic power failure scheduling to correct the operation air demand to obtain the actual operation exhaust air volume of the system, and controlling the operation of the fan according to the corrected operation air demand;
which comprises the following steps: solving the worst hydraulic power failure rate by an off-line method according to the opening rate calculated by the multi-terminal monitoring system, and calculating the hydraulic working conditions of the exhaust pipe network system under different operation opening rates in advance to form a single-value corresponding relation between the worst hydraulic power failure rate and the operation opening rate; in addition, according to the performance matching of the fans, the corresponding relation between the air quantity and the rotating speed of the fans can be obtained, the obtained worst hydraulic power failure scheduling is used for correcting the ideal operation air quantity, and then the operation frequency of the fans is solved according to the corresponding relation between the air quantity and the rotating speed of the fans;
under a certain opening rate, analyzing the hydraulic working condition of a pipe network, wherein the total resistance of the system is the largest when the tail end positions are all gathered at the far end, and the sum of the total air flow of the system under the working condition is the smallest under the same fan frequency; with the sameHydraulic power descheduling minimum value x of each end under sceneminThe result is used as the calculation basis of safety compensation under the corresponding opening rate, and the running rotating speed of the fan is further corrected to be
Figure FDA0002497785770000011
Frequency is corrected to
Figure FDA0002497785770000012
Further gathering the tail end position to the near end and dispersing the tail end position to x under the working condition of two endsminThe results are also pre-calculated and then x for three conditionsminTaking the minimum value as the final basis of the frequency conversion of the fan; wherein N isOperation ofIndicating the rotating speed of the fan under the operating condition; f. ofOperation ofIndicating the fan frequency under operating conditions.
2. The total air volume control method of multi-terminal concentrated exhaust according to claim 1, characterized in that: the total air discharge quantity is obtained by multiplying the calculated opening rate by the designed air discharge quantity of each tail end; correcting the air discharge amount by the worst scheduling to obtain the actual operation air discharge amount of the system; and finally, calculating the running frequency of the fan according to the air exhaust amount, and controlling the variable-frequency running of the fan according to the running frequency.
3. The total air volume control method of multi-terminal concentrated exhaust according to claim 1, characterized in that: the designed air volume of each tail end of the multi-tail-end centralized exhaust system is consistent, and each tail end has the operation requirement of random opening and closing; in the system operation process, if the tail end is monitored to be opened and closed, the operation opening rate is calculated according to the following formula:
Figure FDA0002497785770000013
and further calculating the worst hydraulic power failure rate according to the calculated opening rate result.
4. The total air volume control method of multi-terminal concentrated exhaust according to claim 1, characterized in that:
if the opening rate is not changed, the fan keeps the original rotating speed to operate, and if the opening rate is changed, the fan needs to correspondingly operate in a variable frequency mode; in a ventilation pipeline system, if the hydraulic stability of the system is equal to 1, the total impedance of the system is unchanged, and the total air quantity required by the system and the rotating speed of a fan are in a proportional relation through hydraulic calculation and fan performance matching in advance:
Figure FDA0002497785770000014
the relation between the operating state and the design state is as follows:
Figure FDA0002497785770000021
according to the relation between the rotating speed and the frequency:
Figure FDA0002497785770000022
calculating the running frequency f of the fan under the corresponding working conditionOperation of；
Wherein G is1Representing the system air volume before frequency conversion; g2Representing the system air volume after frequency conversion; n is a radical of1Representing the rotating speed of the fan before frequency conversion; n is a radical of2Representing the rotating speed of the fan after frequency conversion;
Gdesign ofRepresenting the system air volume under the design working condition; gOperation ofRepresenting the system air volume under the operation condition; n is a radical ofDesign ofRepresenting the rotating speed of the fan under the design working condition; n is a radical ofOperation ofIndicating the rotating speed of the fan under the operating condition; f. ofOperation ofRepresenting the fan frequency under the operating condition; p represents the fan power.
5. The total air volume control method of multi-terminal concentrated exhaust according to claim 1, characterized in that:
if the hydraulic stability of the multi-terminal system is not 1, and each opening rate also covers the combined information of a plurality of opening positions, namely a plurality of working conditions exist under one opening rate; under each working condition, different hydraulic power failure scheduling x at each tail end is set as the actual operation flow rate/the flow rate required by design; and calculating the worst hydraulic power failure rate at each opening rate, wherein the worst hydraulic power failure rate is the safety compensation coefficient 1/x at the corresponding opening rate.
6. The control device for multi-terminal concentrated air discharge for realizing the method for controlling the total air volume of multi-terminal concentrated air discharge according to any one of claims 1 to 5, characterized in that: the system at least comprises a variable frequency fan (1), a hydraulic power dispatching calculator (2), a multi-tail-end monitoring system (3), a plurality of exhaust system branch pipes (4), a tail-end opening and closing valve (5) and an exhaust system main pipe (6); the variable frequency fan (1) is connected with an exhaust system main pipe (6) to provide exhaust required by the system, a plurality of exhaust system branch pipes (4) are arranged on the exhaust system main pipe (6), each exhaust system branch pipe (4) is provided with a tail end opening and closing valve (5), a multi-tail end monitoring system (3) is connected with the tail end opening and closing valves (5) arranged on the exhaust system branch pipes (4) to obtain monitoring signals, a worst hydraulic power failure scheduling calculator (2) is connected with the multi-tail end monitoring system (3) to obtain the opening rate of the system, the required operating frequency of the fan of the system is fed back, the worst hydraulic power failure scheduling calculator (2) is connected with the variable frequency fan (1) to transmit the current required operating frequency, and the total air volume control of the system is achieved.
7. The control device for multi-terminal concentrated exhaust according to claim 6, wherein: the variable frequency fan (1) is driven by a direct current or alternating current motor; the hydraulic power dispatching loss calculator is used for finishing calculation of the worst hydraulic power dispatching loss and the running frequency of the fan.
8. The control device for multi-terminal concentrated exhaust according to claim 6, wherein: the multi-terminal monitoring system transmits information in a wired communication mode, and the total opening rate is calculated according to related information by monitoring the opening or closing condition of each terminal.
9. The control device for multi-terminal concentrated exhaust according to claim 8, wherein: and the communication line of the multi-terminal monitoring system is arranged in the sleeve and fixedly installed along the inner wall and the outer wall of the air pipe of the exhaust system.
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CN109630447B (en) * 2018-11-01 2021-04-20 浙江铭振电子股份有限公司 Control method of fan wall and fan wall
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07219558A (en) * 1994-01-28 1995-08-18 Hitachi Ltd Active silencer for duct
CN1711462A (en) * 2002-11-18 2005-12-21 株式会社山武 Fluid detection device
CN101842128A (en) * 2007-05-11 2010-09-22 雷斯梅德有限公司 Automated control for detection of flow limitation
KR20180081656A (en) * 2017-01-06 2018-07-17 엘지전자 주식회사 Chiller system

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07219558A (en) * 1994-01-28 1995-08-18 Hitachi Ltd Active silencer for duct
CN1711462A (en) * 2002-11-18 2005-12-21 株式会社山武 Fluid detection device
CN101842128A (en) * 2007-05-11 2010-09-22 雷斯梅德有限公司 Automated control for detection of flow limitation
KR20180081656A (en) * 2017-01-06 2018-07-17 엘지전자 주식회사 Chiller system

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