CN112483450B - Early warning method of emergency fan with early warning function - Google Patents
Early warning method of emergency fan with early warning function Download PDFInfo
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- CN112483450B CN112483450B CN202011261881.4A CN202011261881A CN112483450B CN 112483450 B CN112483450 B CN 112483450B CN 202011261881 A CN202011261881 A CN 202011261881A CN 112483450 B CN112483450 B CN 112483450B
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
- F04D27/001—Testing thereof; Determination or simulation of flow characteristics; Stall or surge detection, e.g. condition monitoring
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
- F04D27/008—Stop safety or alarm devices, e.g. stop-and-go control; Disposition of check-valves
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- 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
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- 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]
- Y02B30/70—Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating
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- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Control Of Positive-Displacement Air Blowers (AREA)
Abstract
The invention provides an early warning method of an emergency fan with an early warning function, which comprises the following steps: setting a triangle connection mode and a star connection mode; setting an allowable value phi of envelope overlap ratio phimaxBias of electric currentTolerance Δ ImaxSetting a sampling time interval T; calculating and calculating the average value I of three-phase currentpAnd peak value ImaxExtreme value of sound pressure betamaxStored in the control unit; entering a polling mode, controlling the open of the no-load control unit by the control unit, and directly communicating the air inlet and the air outlet of the fan body at the moment to form a no-load working mode of the fan; according to the corresponding connection mode, calculating the current deviation degree in real time, carrying out early warning when the deviation is large, and receiving the sound pressure value beta transmitted by the sound pressure test unit when the deviation is small; when beta is greater than or equal to betamaxThe control unit starts an alarm unit to give an early warning when beta is less than betamaxAnd when the inspection mode is finished, the control unit controls to close the air valve of the no-load control unit, and the air inlet and the air exhaust of the fan body are not communicated at the moment, so that the standby working state of the fan is formed.
Description
[ technical field ] A method for producing a semiconductor device
The invention relates to an early warning method of an emergency fan with an early warning function.
[ background of the invention ]
An emergency fan mainly refers to a smoke prevention and exhaust fan in a building and an emergency fan in an underground space. The fan is characterized in that the fan does not operate at ordinary times and is started to work only under emergency conditions, so that high requirements are provided for the safety of the emergency fan, and the working state of the emergency fan must be ensured. Although relevant requirements are stipulated by national relevant specifications, for example, a smoke prevention and exhaust system is taken as an example, a smoke prevention and exhaust fan needs to be patrolled once every month, the extensive patrolling only can reflect that the fan can operate, potential hidden dangers of the fan cannot be judged, the working state of the fan cannot be fundamentally ensured, and even the extensive patrolling is just the main reason for burning out the fan motor under certain conditions.
The problem of the fan is mostly concentrated on the burning of the motor. The main reasons for burnout are as follows: 1) the power supply is open-phase. Because the starting current of the emergency fan at the starting moment is 5 to 7 times of the normal working current, the current of the control circuit is overlarge, so that the power supply is in phase failure due to one-time circuit breaking.
2) The motor is open-phase. In practical engineering, the common reasons are that the motor is overheated due to loosening of the joint, mechanical injury, breakage of the wiring terminal and the like, and the motor is burnt in a short time.
3) The control of an air valve linked with the fan fails, the fan is operated in a high-pressure area for a long time, so that the power of a motor shaft is increased, and the current of the motor exceeds a rated value; the temperature rise of the motor exceeds the rated temperature rise to cause burnout.
Through practical analysis, the motor is not burnt at all when the fan can rotate, and just when the started motor is overheated, which is particularly important for the emergency fan.
The chinese patent application No. 201520180697.5 proposes an automatic control device for protecting the no-load starting current of a centrifugal fan, which reduces the excessive starting current when the fan is started by controlling the opening time of an outlet air valve of the fan. The chinese patent application No. 201721865017.9 proposes an intelligent fan electric cabinet with an automatic effective protection function for accidental light or heavy load.
Although various solutions are provided for solving the problem, the difficulty of the emergency fan is early warning, if the problem is found in advance in daily routing inspection and is eliminated in advance, the emergency fan can be guaranteed to fully play a role when an accident occurs, and the safety performance is improved.
According to the practical summary of engineering, when the motor is out of phase or the fan impeller is eccentric when being installed or the bearing works unsatisfactorily, the motor can generate sharp sound. Therefore, the invention provides an early warning method of an emergency fan with an early warning function.
[ summary of the invention ]
The invention aims to solve the technical problem of providing an early warning method of an emergency fan with an early warning function, which can be used for early warning potential safety hazards formed by phase loss or fan bearing operation faults and improper installation of a fan impeller.
The invention is realized by the following steps:
an early warning method of an emergency fan with an early warning function is disclosed, wherein the fan comprises a control center, a box body, a fan body, a control unit, a phase failure detection unit, a sound pressure detection unit, a no-load control unit and an alarm unit;
the front and the back of the box body are respectively provided with a first air inlet and a first air outlet, a partition plate is arranged in the box body and divides the interior of the box body into a left chamber and a right chamber, the left chamber is communicated with the first air inlet, and the right chamber is communicated with the first air outlet;
the fan body is provided with a second air inlet and a second air outlet, the fan body is arranged in the left cavity of the box body, and the second air outlet of the fan body penetrates through the partition plate and is positioned in the right cavity;
the open-phase detection unit is connected with a motor of the fan body, the sound pressure detection unit is close to the second air outlet, and the no-load control unit is arranged on the partition plate and controls the partition plate to be opened and closed; the open-phase detection unit, the sound pressure detection unit, the no-load control unit and the alarm unit are all connected with the control unit, and the control unit is connected with the control center;
the method comprises the following steps:
step 1, setting a triangle connection mode and a star connection mode in a control unit;
step 4, entering a polling mode, controlling the open of the no-load control unit by the control unit, and directly communicating the air inlet and the air exhaust of the fan body at the moment to form the no-load working mode of the fan;
step 5.1, the control unit receives envelope information of the three-phase current actually measured by the defect detection unit, calculates the contact ratio phi of the envelope between the three phases, and when the phi is less than or equal to the phimaxCalculating the current deviation in real timeWherein: i isi,maxpRepresenting the maximum value of the mean value over the period of the test of the current of any of the three phases, when Δ I is less than Δ ImaxEntering step 6, when the delta I is larger than or equal to the delta ImaxThe control unit starts an alarm unit and enters the step 4 after maintenance;
when phi is>ΦmaxThen step 6 is entered;
step 5.2, the control unit receives envelope information of the three-phase current actually measured by the defect detection unit, calculates the contact ratio phi of the envelopes among the three phases, and when the phi is less than or equal to the phimaxCalculating the current deviation in real timeWhen Δ I is less thanEntering step 6;
when Δ I is equal to or greater thanThe control unit starts an alarm unit, and the step 4 is carried out after maintenance;
when phi is>ΦmaxEntering step 6;
when beta is less than betamaxIf yes, entering step 7;
and 7, finishing the inspection mode, controlling the air valve of the no-load control unit to be closed by the control unit, and at the moment, not communicating the air inlet and the air outlet of the fan body to form a standby working state of the fan.
Furthermore, the open-phase detection unit comprises a hall current sensor, a shaping circuit and an envelope detection circuit, the pole of the hall current sensor is arranged on a line in front of a three-phase wiring terminal of the motor, an output voltage signal of the hall current sensor is sequentially connected into the shaping circuit and the envelope detection circuit, and the envelope detection signal is connected with the control unit.
Furthermore, the sound pressure detection unit comprises a noise sensor and a preamplifier, the noise sensor is arranged on the inner wall of the box body and is close to the second air outlet, and a voltage signal of the noise sensor is connected to the preamplifier and then connected with the control unit.
Further, the no-load control unit is an air valve.
Furthermore, the alarm unit comprises an alarm bell and an alarm module, the alarm bell is arranged on the outer surface of the box body, and the alarm module is arranged in the control center and connected with the control unit.
The invention has the following advantages:
compared with the prior art, the emergency fan with the early warning function and the early warning method are provided according to the operation characteristics of the emergency fan and by considering the hidden danger of the frequent starting of an emergency fan system to the safety of the fan. Therefore, the following advantages are provided:
1) the no-load control unit is arranged, so that the safety damage of a fan motor caused by the starting current of the fan is greatly reduced, and meanwhile, the test time of fan polling is greatly reduced;
2) the potential safety hazard of phase failure is conveniently and quickly tested according to the contact ratio phi and the current deviation degree delta I of the current envelope curve of each phase; the purpose of early warning is achieved;
3) according to the operation sound pressure of the fan, potential safety hazards formed by phase loss or fan bearing operation faults and improper fan impeller installation are determined, and the early warning purpose is achieved;
4) the alarm module is provided with an alarm bell and can display fault alarm in the control center, so that the alarm module is convenient and quick to handle.
[ description of the drawings ]
The invention will be further described with reference to the following examples with reference to the accompanying drawings.
Fig. 1 is a schematic structural diagram of an emergency fan with an early warning function according to the present invention.
Fig. 2 is a circuit connection block diagram of an emergency fan with an early warning function according to the present invention.
Fig. 3 is a flow chart of the operation of the emergency fan with the early warning function according to the invention.
[ detailed description ] embodiments
The technical solution of the present invention will be described clearly and completely with reference to the accompanying drawings and the detailed description. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are conventional products which are not indicated by manufacturers and are commercially available.
In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
Referring to fig. 1 to 3, in the emergency blower with an early warning function according to the present invention, a control unit 3, a phase failure detection unit 4, a sound pressure detection unit 5, a no-load control unit 6, and an alarm unit 7 are added to a control center 100, a box 1, and a blower body 2 of an original emergency blower;
a first air inlet 11 and a first air outlet 12 are respectively formed in the front and the rear of the box body 1, a partition plate 13 is arranged in the box body 1, the partition plate 13 divides the interior of the box body into a left chamber 14 and a right chamber 15, the left chamber 14 is communicated with the first air inlet 11, and the right chamber 15 is communicated with the first air outlet 12;
the fan body 2 is provided with a second air inlet 21 and a second air outlet 22, the fan body 2 is arranged in the left chamber 14 of the box body, and the second air outlet 22 of the fan body 2 penetrates through the partition plate 13 and is positioned in the right chamber 15;
the open-phase detection unit 4 is connected with a motor 23 of the fan body 2, the sound pressure detection unit 5 is close to the second air outlet 22, and the no-load control unit 6 is arranged on the partition plate 13 and controls the partition plate 13 to be opened and closed;
the open-phase detection unit 4, the sound pressure detection unit 5, the no-load control unit 6 and the alarm unit 7 are all connected with the control unit 3, and the control unit 3 is connected with the control center 100.
In one embodiment, the following is preferred: the open-phase detection unit 4 comprises a hall current sensor 41, a shaping circuit 42 and an envelope detection circuit 43, the pole of the hall current sensor 41 is arranged on a line in front of a three-phase wiring terminal of the motor 23, an output voltage signal of the hall current sensor 41 is sequentially connected to the shaping circuit 42 and the envelope detection circuit 43, and the envelope detection signal 43 is connected with the control unit 3.
In one embodiment, the following is preferred: the sound pressure detection unit 5 comprises a noise sensor 51 and a preamplifier 52, the noise sensor 51 is arranged on the inner wall of the box body 1 and close to the second air outlet 22, and a voltage signal of the noise sensor 51 is connected to the preamplifier 52 and then connected to the control unit 3.
In one embodiment, the following is preferred: the no-load control unit 6 is an air valve 61.
In one embodiment, the following is preferred: the alarm unit 7 comprises an alarm bell 74, and the alarm bell 74 is arranged on the outer surface of the box body 1.
In one embodiment, the following is preferred: the alarm unit 7 further comprises an alarm module 72, and the alarm module 72 is disposed in the control center 100 and connected to the control unit 3. The motor 23 is electrically connected with the control center 100.
In another embodiment of the invention, the early warning operation method of the invention is as follows:
step 1, a triangle connection mode and a star connection mode are set in a control unit 3;
step 4, entering a polling mode, wherein the control unit 3 controls to open the air valve 61 of the no-load control unit 6, and at the moment, the inlet air is directly communicated with the outlet air (namely, the inlet air of the second air inlet 21 is discharged from the second air outlet 22 and then enters the second air inlet 21 again through the air valve 61 on the partition plate 13, and the circulation is carried out in this way), so that the no-load working mode of the fan is formed;
step 5.1, the control unit 3 receives envelope information of three-phase current actually measured by the defect detection unit 4, calculates the coincidence degree phi of the envelopes among the three phases, and when the phi is less than or equal to the phimaxCalculating the current deviation in real timeWherein: I.C. Ai,maxpRepresenting the maximum value of the mean value over the period of the test of the current of any of the three phases, when Δ I is less than Δ ImaxEntering step 6, when Δ I is larger than or equal to Δ ImaxThe control unit 3 starts an alarm bell 71 to give an alarm, sends an instruction to an alarm module 72 of the control center 100 to display a fault alarm, and enters the step 4 after maintenance;
when phi is>ΦmaxThen step 6 is entered;
step 5.2, the control unit 3 receives envelope information of the three-phase current actually measured by the defect detection unit 4, calculates the coincidence degree phi of the envelopes among the three phases, and when the phi is less than or equal to the phimaxCalculating the current deviation in real timeWhen Δ I is less thanEntering step 6;
when Δ I is equal to or greater thanThe control unit 3 starts an alarm bell 71 to give an alarm, sends an instruction to an alarm module 72 of the control center 100 to display a fault alarm, and enters the step 4 after maintenance;
when phi is>ΦmaxEntering step 6;
when beta is less than betamaxIf yes, entering step 7;
and 7, finishing the inspection mode, controlling the air valve 61 of the no-load control unit 13 to be closed by the control unit 3, and at the moment, not communicating the air inlet with the air exhaust to form a waiting working state of the fan.
Compared with the prior art, the emergency fan with the early warning function and the early warning method are provided according to the operation characteristics of the emergency fan and by considering the hidden danger of the frequent starting of an emergency fan system to the safety of the fan. Therefore, the following advantages are provided:
1) the no-load control unit is arranged, so that the safety damage of a fan motor caused by the starting current of the fan is greatly reduced, and meanwhile, the test time of fan polling is greatly reduced;
2) the potential safety hazard of phase failure is conveniently and quickly tested according to the contact ratio phi and the current deviation degree delta I of the current envelope curve of each phase; the purpose of early warning is achieved;
3) according to the operation sound pressure of the fan, potential safety hazards formed by phase loss or fan bearing operation faults and improper fan impeller installation are determined, and the early warning purpose is achieved;
4) the alarm module is provided with an alarm bell and can display fault alarm in the control center, so that the alarm module is convenient and quick to handle.
While specific embodiments of the invention have been described, it will be understood by those skilled in the art that the specific embodiments described are illustrative only and are not limiting upon the scope of the invention, as equivalent modifications and variations as will be made by those skilled in the art in light of the spirit of the invention are intended to be included within the scope of the appended claims.
Claims (5)
1. The early warning method of the emergency fan with the early warning function is characterized by comprising the following steps of: the fan comprises a control center, a box body, a fan body, a control unit, a phase failure detection unit, a sound pressure detection unit, a no-load control unit and an alarm unit;
the front and the back of the box body are respectively provided with a first air inlet and a first air outlet, a partition plate is arranged in the box body and divides the interior of the box body into a left chamber and a right chamber, the left chamber is communicated with the first air inlet, and the right chamber is communicated with the first air outlet;
the fan body is provided with a second air inlet and a second air outlet, the fan body is arranged in the left cavity of the box body, and the second air outlet of the fan body penetrates through the partition plate and is positioned in the right cavity;
the open-phase detection unit is connected with a motor of the fan body, the sound pressure detection unit is close to the second air outlet, and the no-load control unit is arranged on the partition plate and controls the partition plate to be opened and closed; the open-phase detection unit, the sound pressure detection unit, the no-load control unit and the alarm unit are all connected with the control unit, and the control unit is connected with the control center;
the method comprises the following steps:
step 1, setting a triangle connection mode and a star connection mode in a control unit;
step 2, setting an allowable value phi of the envelope overlap ratio phi in a control unitmaxAllowable deviation of current Δ ImaxSetting a sampling time interval T, whereini, j represent different phase groups, ω represents the phase angle,0.02 is the time period of alternating current 50 Hz;
step 3, counting the running parameters of the three-phase current and the sound pressure of the motor of the fan body in a plurality of sampling periods, taking the running parameters as training samples, and calculating the average value I of the three-phase currentpAnd peak value ImaxExtreme value of sound pressure betamaxStored in the control unit;
step 4, entering a polling mode, controlling the open of the no-load control unit by the control unit, and directly communicating the air inlet and the air exhaust of the fan body at the moment to form the no-load working mode of the fan;
step 5, entering step 5.1 when the triangle connection mode is selected to be set, and entering step 5.2 when the star connection mode is selected to be set;
step 5.1, the control unit receives envelope information of the three-phase current actually measured by the defect detection unit, calculates the contact ratio phi of the envelope between the three phases, and when the phi is less than or equal to the phimaxCalculating the current deviation in real timeWherein: i isi,maxpRepresenting the maximum value of the mean value over the period of the test of the current of any of the three phases, when Δ I is less than Δ ImaxEntering step 6, when the delta I is larger than or equal to the delta ImaxThe control unit starts an alarm unit and enters the step 4 after maintenance;
when phi is>ΦmaxThen entering step 6;
step 5.2, the control unit receives envelope information of the three-phase current actually measured by the defect detection unit, calculates the contact ratio phi of the envelopes among the three phases, and when the phi is less than or equal to the phimaxCalculating the current deviation in real timeWhen Δ I is less thanEntering step 6;
when Δ I is equal to or greater thanThe control unit starts an alarm unit, and the step 4 is carried out after maintenance;
when phi is>ΦmaxThen entering step 6;
step 6, the control unit receives the sound pressure value beta transmitted by the sound pressure test unit, and when the beta is more than or equal to the betamaxThe control unit starts an alarm unit, and the step 4 is carried out after maintenance;
when beta is less than betamaxIf yes, entering step 7;
and 7, finishing the inspection mode, controlling the no-load control unit to be closed by the control unit, and at the moment, preventing the air inlet and the air exhaust of the fan body from being communicated, so that the waiting working state of the fan is formed.
2. The early warning method of the emergency fan with the early warning function according to claim 1, wherein: the open-phase detection unit comprises a Hall current sensor, a shaping circuit and an envelope detection circuit, the pole of the Hall current sensor is arranged on a circuit in front of a three-phase wiring terminal of the motor, an output voltage signal of the Hall current sensor is sequentially connected into the shaping circuit and the envelope detection circuit, and the envelope detection signal is connected with the control unit.
3. The early warning method of the emergency fan with the early warning function according to claim 1, wherein: the sound pressure detection unit comprises a noise sensor and a preamplifier, the noise sensor is arranged on the inner wall of the box body and is close to the second air outlet, and a voltage signal of the noise sensor is connected into the preamplifier and then is connected with the control unit.
4. The early warning method of the emergency fan with the early warning function according to claim 1, wherein: the no-load control unit is an air valve.
5. The early warning method for the emergency fan with the early warning function as claimed in claim 1, wherein: the alarm unit comprises an alarm bell and an alarm module, the alarm bell is arranged on the outer surface of the box body, and the alarm module is arranged in the control center and connected with the control unit.
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CN103207604A (en) * | 2013-03-24 | 2013-07-17 | 北京工业大学 | Online monitoring and fault diagnosis system of operating state of embedded ventilator |
CN103321933A (en) * | 2013-05-22 | 2013-09-25 | 北京工业大学 | Fan state online monitoring system and method based on advanced reduced instruction-set computer machine (ARM) and ZigBee |
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