A switch cabinet fire early warning device and method based on pyrolysis particle sensor

Abstract

The application discloses a kind of based on pyrolysis particle sensor switch cabinet fire early warning device and method, belong to substation fire early warning field, including monitoring host computer, pyrolysis particle and characteristic gas monitoring module, environmental monitoring module and air extraction module, pyrolysis particle and characteristic gas monitoring module, environmental monitoring module are electrically connected with monitoring host computer respectively;Air extraction module includes gas conduit, controllable one-way air valve and gas collecting pipe, gas conduit is connected to the sealing flange on the back of switch cabinet;In the back of switch cabinet, close to cable chamber top hole, then install sealing flange, gas conduit passes through sealing flange, connects switch cabinet cable chamber space;The gas conduit of switch cabinet, after controllable one-way air valve, converge in gas collecting pipe, then the outlet of gas collecting pipe is connected with the sealing box of pyrolysis particle and characteristic gas monitoring module by a section of gas conduit.The application can find overheating defect very early, with the advantages of safety, economy and accuracy.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of substation fire early warning, more specifically, relates to a switch cabinet fire early warning device and method based on pyrolysis particle sensor. BACKGROUND

[0002] The switch cabinet is an important equipment of the power system, however, switch cabinet fire failure often occurs, causing huge economic losses. Especially the switch cabinet cable room, the probability of failure is greater.

[0003] The switch cabinet cable room belongs to high pressure cabin, and sensors cannot be installed in its space. Some switch cabinets are equipped with smoke alarm or temperature sensors, which have low sensitivity. When the alarm is sounded, a more serious open fire has occurred. SUMMARY

[0004] The purpose of the present application is to overcome the shortcomings of the prior art, provide a switch cabinet fire early warning device and method based on pyrolysis particle sensor, which can detect overheating defects at an early stage, and has the advantages of safety, economy and accuracy.

[0005] The purpose of the present application is achieved by the following scheme:

[0006] A switch cabinet fire early warning device based on pyrolysis particle sensor, comprising a monitoring host, a pyrolysis particle and characteristic gas monitoring module, an environmental monitoring module and an air extraction module, the pyrolysis particle and characteristic gas monitoring module, the environmental monitoring module are respectively electrically connected with the monitoring host;

[0007] The air extraction module comprises a gas conduit, a controllable one-way air valve and a gas collecting pipe, the gas conduit is connected to the sealing flange on the back of the switch cabinet; on the back of the switch cabinet, near the top opening of the cable room, then install the sealing flange, the gas conduit passes through the sealing flange, connects the switch cabinet cable room space; all the gas conduits of the switch cabinet converge in the gas collecting pipe after passing through the controllable one-way air valve, then the outlet of the gas collecting pipe is connected with the sealing box of the pyrolysis particle and characteristic gas monitoring module through a gas conduit;

[0008] The monitoring host is used for collecting data of the pyrolysis particle and characteristic gas monitoring module, the environmental monitoring module and the air extraction module, and performing overheating defect or fire warning through algorithm.

[0009] Further, the monitoring host specifically collects data of the pyrolysis particle and characteristic gas monitoring module, the environmental monitoring module and the air extraction module through the 485 bus, and displays the monitoring data through the screen.

[0010] Further, the monitoring host is also connected with the controllable one-way air valve, and controls the conduction and closing of the air valve.

[0011] Further, the pyrolyzed particle and characteristic gas monitoring module comprises a sealed box, a pyrolyzed particle sensor and a characteristic gas sensor.

[0012] Further, the sealed box has an air inlet and an air outlet at two ends, and the air inlet and the air outlet are respectively provided with sealing flanges connected with the gas guide pipes of the air extraction module; the pyrolyzed particle sensor and the characteristic gas sensor are installed on the top of the sealed box and communicate with the monitoring host through a bus.

[0013] Further, the characteristic gas sensor comprises CO, C2H4, C2H6 and CH3cl, and the ranges and resolutions of the four gas sensors are the same.

[0014] Further, the environmental monitoring module comprises an air quality sensor and a temperature and humidity sensor, and is installed on the outer wall of the measured switch cabinet.

[0015] Further, the air extraction module further comprises a vacuum pump and a gas flow meter, the vacuum pump is connected with the gas flow meter, and the gas flow meter is connected with the gas guide pipe; in the monitoring process, the air extraction flow is monitored through the gas flow meter.

[0016] A switch cabinet fire warning method based on a pyrolyzed particle sensor, based on the device of any one of the above, comprising the following steps:

[0017] Step one, the controllable one-way valves 1-n are opened by the monitoring host, and the air extraction flow is adjusted by the vacuum pump control;

[0018] Step two, the data of the environmental monitoring module and the pyrolyzed particle and characteristic gas monitoring module are monitored by the monitoring host, the pyrolyzed particle monitoring value is R, the monitoring values of the CO, C2H4, C2H6 and CH3cl characteristic gases are G1, G2, G3 and G4 respectively, and the value of PM2.5 in the air quality sensor is K; the data processing and determination are performed in the following manner:

[0019] Step (1), if the pyrolyzed particle monitoring data R does not exceed the set threshold TR, i.e. R < TR, at this time G1, G2, G3 and G4 are all 0, it indicates that the working state of the switch cabinet is normal, and the current switch tube cable chamber operating state score is a set full score, and the set full score includes 10 points.

[0020] Step (2), if the pyrolyzed particle monitoring data R does not exceed the set threshold TR, i.e. R < TR, at this time one of G1, G2, G3 and G4 is not 0, and the time duration T1 seconds or more, the current state score is calculated according to the following formula:

[0021] State S = k1*SR + k2*SG1 + k3*SG2 + k4*SG3 + k5*SG4

[0022] SR, SG1, SG2, SG3, SG4 are state fractions of pyrolysis particles, CO, C2H4, C2H6, CH3cl characteristic gas respectively; k1, k2, k3, k4, k5 are state fraction weight coefficients respectively; at this time, SR = 10; S = k1*10 + k2*SG1 + k3*SG2 + k4*SG3 + k5*SG4; according to different scores, different risk levels are divided and corresponding measures are taken;

[0023] Step (3), if the pyrolysis particle monitoring data R exceeds the set threshold TR at t1, that is, R > TR, and the value of R remains R > TR within T2 time period after t1, at this time, according to the value of K, if:

[0024] 1) K exceeds the set threshold TK at t2, and the value of K remains K > TK within T2 time period after t2; if t1 > t2, then see the values of G1, G2, G3, G4: if G1, G2, G3, G4 are all 0, it indicates that the switch cabinet working state is normal, and the current switch tube cable chamber operating state score is the set full score, which includes 10 points; if one of G1, G2, G3, G4 is not 0 and the time duration of not 0 is T1 seconds or more, then the state score is calculated, different risk levels are divided according to different state scores, and corresponding measures are taken;

[0025] 2) K exceeds the set threshold TK at t2, and the value of K remains K > TK within T2 time period after t2, t1 < t2; or, K has never exceeded TK, then the following way is adopted for processing:

[0026] First step: determine which switch cabinet cable chamber has fire hazard, close the controllable one-way air valve 1 through the monitoring host control, and monitor whether the value of R presents a downward trend, that is, R' < 0, R' is the first derivative of R data, after the set time from this time, if yes, it is the first switch cabinet, if not, open the controllable one-way air valve 1; then close the controllable one-way air valve 2, repeat the judgment until the switch cabinet cable chamber with fire hazard is found;

[0027] Second step: evaluate the risk level of the switch cabinet: S = k1*SR + k2*SG1 + k3*SG2 + k4*SG3 + k5*SG4; wherein, SR = 10 - (R - K) / K, if the calculated SR is less than 0, then take SR = 0;

[0028] SG1: if G1>0, and time lasts T1 seconds and above, SG1=0; otherwise SG1=10;

[0029] SG2: if G2>0, and time lasts T1 seconds and above, SG2=0; otherwise SG2=10;

[0030] SG3: if G3>0, and time lasts T1 seconds and above, SG3=0; otherwise SG3=10;

[0031] SG4: if G4>0, and time lasts T1 seconds and above, SG4=0; otherwise SG4=10;

[0032] Third step: according to the risk assessment level, corresponding measures are taken.

[0033] Further, the threshold TR and TK are dynamically adjusted according to the temperature and humidity measured by the environment monitoring module; the state weight coefficients are initially processed as follows: k1=0.6, k2=0.04, k3=0.08, k4=0.08, k5=0.2; and the initial weight coefficients are obtained through expert evaluation and analytic hierarchy process, which can be dynamically corrected through different scenes and actual conditions.

[0034] The beneficial effects of the present application include:

[0035] The present application adopts the form of an air extraction duct, without the need to install sensors inside the cable chamber of the switch cabinet, and is safer and more feasible.

[0036] The present application can use one pyrolysis particle sensor to determine which switch cabinet has hidden dangers, and is more economical.

[0037] The present application removes interference through comparison of environmental particle monitoring data, and uses a pyrolysis particle sensor and a gas sensor to comprehensively judge, and is more accurate. BRIEF DESCRIPTION OF DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0039] Figure 1 The structural block diagram of the device of the embodiment of the present application. DETAILED DESCRIPTION

[0040] All features disclosed in this specification, and / or all methods or processes disclosed in this specification may be combined in any combination, and / or substituted, unless specific excluded, in whole or part, by any preceding or following disclosure.

[0041] The specific implementation process of the present application is as follows:

[0042] In one aspect, in a preferred embodiment, a pyrolysis particle sensor-based switch cabinet early fire warning device is provided, comprising a monitoring host, a pyrolysis particle and characteristic gas monitoring module, an environment monitoring module and an air extraction module.

[0043] The main function of the monitoring host is to collect data of the pyrolysis particle and characteristic gas monitoring module, the environment monitoring module and the air extraction module through the 485 bus, and to perform overheating defect or fire warning through the corresponding algorithm, and to display through the screen. In addition, the monitoring host is connected with the controllable one-way air valve through the control circuit to control the conduction and closing of the air valve.

[0044] The pyrolysis particle and characteristic gas monitoring module is mainly composed of a sealed box, a pyrolysis particle sensor and a characteristic gas sensor. The sealed box is made of acrylic or epoxy material, and the size is not greater than 0.4m*0.3m*0.3m. There is an air inlet and an air outlet at both ends of the sealed box, and a sealing flange is installed respectively. The sealing flanges are connected with the gas guide pipe of the air extraction module. The pyrolysis particle sensor and the characteristic gas sensor are installed on the top of the sealed box, and communicate with the monitoring host through the 485 bus.

[0045] The characteristic gas sensor used in the present application includes CO, C2H4, C2H6 and CH3cl. The range and resolution of the four gas sensors are the same.

[0046] The environment monitoring module is mainly composed of an air quality sensor and a temperature and humidity sensor, and is installed on the outer wall of the measured switch cabinet.

[0047] The air extraction module is mainly composed of a vacuum pump, a gas flow meter, a gas guide pipe (blue line in the figure), a controllable one-way air valve and a gas collecting pipe. During the monitoring process, the air extraction flow is preferably monitored by the gas flow meter at 5L / min.

[0048] The gas guide pipe is connected to the sealing flange on the back of the switch cabinet. First, a hole is made on the back of the switch cabinet near the top of the cable chamber, and then the sealing flange is installed. The gas guide pipe passes through the sealing flange and connects the cable chamber space of the switch cabinet. After passing through the controllable one-way valve, all the gas guide pipes of the switch cabinet converge in the gas collecting pipe, and then the outlet of the gas collecting pipe is connected to the sealed box of the pyrolysis particle and characteristic gas monitoring module through a section of gas guide pipe.

[0049] In another aspect, in a preferred embodiment, a pyrolysis particle sensor-based switch cabinet early-stage fire warning method is provided, as shown in Figure 1 After the above device is installed, the controllable one-way valves 1-n are opened by the monitoring host computer, and the vacuum pump is adjusted to an appropriate output, so that the flow rate of the flow meter is about 5 L / min.

[0050] Through monitoring the data of the monitoring host computer, the environmental monitoring module, and the pyrolysis particle and characteristic gas monitoring module, the pyrolysis particle monitoring value is R, the monitoring values of the CO, C2H4, C2H6, and CH3cl characteristic gases are G1, G2, G3, and G4, respectively, and the value of PM2.5 in the air quality sensor is K.

[0051] Further, data processing and determination are performed as follows:

[0052] (1) If the pyrolysis particle monitoring data R does not exceed the set threshold TR, i.e., R < TR, and G1, G2, G3, and G4 are all 0 at this time, it indicates that the switch cabinet is in a normal working state, and the current switch tube cable chamber operating state score is 10.

[0053] (2) If the pyrolysis particle monitoring data R does not exceed the set threshold TR, i.e., R < TR, and one of G1, G2, G3, and G4 is not 0 at this time, and the time duration of not being 0 is T1 seconds or more, the current state score is calculated according to the following formula (T1 can be 5 seconds). State score S = k1*SR+k2*SG1*k3*SG2+k4*SG3+k5*SG4; SR, SG1, SG2, SG3, and SG4 are the state scores of the pyrolysis particle, CO, C2H4, C2H6, and CH3cl characteristic gas, respectively. K1, k2, k3, k4, and k5 are the state score weight coefficients.

[0054] At this time, SR = 10, so S = k1*10+k2*SG1*k3*SG2+k4*SG3+k5*SG4; and the processing is performed according to the following Table 1:

[0055] Table 1

[0056]

[0057] (3) If the pyrolysis particle monitoring data R exceeds the set threshold TR at t1, i.e., R > TR, and the value of R remains R > TR within a T2 time period after t1 (T2 can be 1 second or 2 seconds).

[0058] At this time, the value of K needs to be evaluated again. If:

[0059] 1) K exceeds the set threshold value TK at time t2, and the value of K remains K > TK after t2 for a period of T2 (the value of TK can be set to be consistent with TR);

[0060] If t1 > t2, then look at the values of G1, G2, G3, and G4 again:

[0061] (A) If G1, G2, G3, and G4 are all 0, it indicates that the switch cabinet is in a normal working state. The current switch tube cable chamber operation state score is 10 points.

[0062] (B) If one of G1, G2, G3, and G4 is not 0 and the time duration is T1 seconds or more, calculate the state score, divide different risk levels according to different state scores, and take corresponding measures. The specific processing can be carried out according to the method of (2).

[0063] 2) K exceeds the set threshold value TK at time t2, and the value of K remains K > TK after t2 for a period of T2, t1 < t2;

[0064] Alternatively, K has not exceeded TK all the time, and the following processing is carried out:

[0065] First step: Determine which switch cabinet cable chamber has fire hazards

[0066] Close the controllable one-way air valve 1 through the monitoring host, and monitor whether the value of R presents a downward trend within 30 seconds after this time, i.e. R' < 0 (R' is the first derivative of R data), if so, it is the first switch cabinet, if not, open the controllable one-way air valve 1.

[0067] Then close the controllable one-way air valve 2 and repeat the above steps to determine. Until it is determined which switch cabinet cable chamber has fire hazards.

[0068] Second step: Evaluate the risk level of the switch cabinet

[0069] S = k1*SR + k2*SG1 + k3*SG2 + k4*SG3 + k5*SG4;

[0070] Wherein, SR = 10 - (R - K) / K, if the calculated SR is less than 0, then take SR = 0;

[0071] SG1: If G1 > 0 and the time duration is T1 seconds or more, SG1 = 0; otherwise, SG1 = 10;

[0072] SG2: If G2 > 0 and the time duration is T1 seconds or more, SG2 = 0; otherwise, SG2 = 10;

[0073] SG3: if G3>0 and time lasts T1 seconds and above, SG3=0; otherwise, SG3=10;

[0074] SG4: if G4>0 and time lasts T1 seconds and above, SG4=0; otherwise, SG4=10;

[0075] Third step: according to the risk assessment, take corresponding measures, as shown in the following table 2.

[0076] Table 2

[0077]

[0078] In the above embodiment, the threshold TR and TK need to be dynamically adjusted according to the temperature and humidity measured by the environment monitoring module.

[0079] In the above embodiment, the initial values of the weight coefficients are processed as follows: k1=0.6, k2=0.04, k3=0.08, k4=0.08, and k5=0.2. The basis for the initial values of the weight coefficients is that through the laboratory test data in the early stage, it is found that the sensitivity of the pyrolysis particles is always higher than that of the gas sensor, so the score weight of the pyrolysis particles is higher. Among the four gases, if CH3Cl gas containing chlorine element appears, it indicates that the outer skin PVC material of the cable starts to pyrolyze (indicating that the internal temperature is higher), so among the gases, the weight of G4 is higher. CO may be disturbed to a certain extent, so the weight of CO is relatively small. Then, through expert evaluation and analytic hierarchy process, the initial weight coefficients are obtained. These weight coefficients can also be dynamically corrected through different scenarios and actual situations.

[0080] The units described in the embodiments of the present application can be implemented in software or hardware, and the described units can also be arranged in a processor. In some cases, the names of these units do not constitute a limitation on the units themselves.

[0081] According to an aspect of an embodiment of the present application, a computer program product or computer program is provided, which includes computer instructions stored in a computer readable storage medium. The processor of the computer device reads the computer instructions from the computer readable storage medium, and the processor executes the computer instructions, so that the computer device executes the method provided in the various optional implementation manners described above.

[0082] As another aspect, the embodiments of the present application also provide a computer readable medium, which can be included in the electronic device described in the above embodiments, or can exist independently without being assembled into the electronic device. The computer readable medium carries one or more programs, which, when executed by the electronic device, enable the electronic device to implement the method described in the above embodiments.

Claims

1. A pyrolytic particle sensor-based switchgear fire early warning method, characterized by, The method is based on the pyrolysis particle sensor switch cabinet fire warning device, the device includes monitoring host, pyrolysis particle and characteristic gas monitoring module, external environment monitoring module and air extraction module, the pyrolysis particle and characteristic gas monitoring module, external environment monitoring module are electrically connected with monitoring host respectively;The air extraction module includes gas conduit, controllable one-way air valve and gas collecting pipe, and the gas conduit is connected to the sealing flange on the back of the switch cabinet;On the back of the switch cabinet, close to the cable chamber top opening, then install the sealing flange, the gas conduit passes through the sealing flange, connects the switch cabinet cable chamber space;All the gas conduits of the switch cabinet converge in the gas collecting pipe through the controllable one-way air valve, and then the outlet of the gas collecting pipe is connected to the sealing box of the pyrolysis particle and characteristic gas monitoring module through a gas conduit;The monitoring host is used for collecting the data of the pyrolysis particle and characteristic gas monitoring module, external environment monitoring module and air extraction module, and performing overheating defect or fire warning through algorithm;The external environment monitoring module includes air quality sensor and temperature and humidity sensor, and is installed on the outer wall of the measured switch cabinet; And the following steps are performed: Step one, the monitoring host controls the controllable one-way valve to be opened, and adjusts the vacuum pump to control the air extraction flow; Step two, the data of the external environment monitoring module and the pyrolysis particle and characteristic gas monitoring module are monitored through the monitoring host, the pyrolysis particle monitoring value is R, the monitoring values of CO, C2H4, C2H6 and CH3cl characteristic gases are G1, G2, G3 and G4 respectively, and the value of PM2.5 in the air quality sensor is K;Data processing and determination are performed in the following manner: Step (1), if the pyrolysis particle monitoring data R does not exceed the set threshold TR, that is, R<TR, and G1, G2, G3 and G4 are all 0 at this time, it indicates that the working state of the switch cabinet is normal, and the current switch tube cable chamber operating state score is the set full score, and the set full score includes 10 points; Step (2), if the pyrolysis particle monitoring data R does not exceed the set threshold TR, that is, R<TR, and one of G1, G2, G3 and G4 is not 0 at this time, and the time duration of not being 0 is T1 seconds or more, then the current state score is calculated according to the following formula: State score S=k1*SR+k2*SG1*k3*SG2+k4*SG3+k5*SG4; SR, SG1, SG2, SG3 and SG4 are the state scores of pyrolysis particle, CO, C2H4, C2H6 and CH3cl characteristic gas respectively;K1, k2, k3, k4 and k5 are state score weight coefficients;At this time, SR=10;S=k1*10+k2*SG1*k3*SG2+k4*SG3+k5*SG4;According to different state scores, different risk levels are classified and corresponding measures are taken; Step (3), if the pyrolysis particle monitoring data R exceeds the set threshold TR at t1, that is, R>TR, and the value of R remains R>TR within T2 time period after t1, then the value of K is evaluated according to the value of K, if: 1) K exceeds the set threshold TK at t2, and the value of K remains K>TK state within T2 time period after t2; if t1>t2, then look at G1, G2, G3, G4 values: if G1, G2, G3, G4 are all 0, it indicates that the switch cabinet is in normal working state, and the current switch tube cable chamber operation state score is set to full score, which includes 10 points; if G1, G2, G3, G4 is not 0, and the time is T1 seconds or more, the state score is calculated, different risk levels are divided according to different state scores, and corresponding measures are taken; 2) K exceeds the set threshold TK at t2, and the value of K remains K>TK state within T2 time period after t2, t1<t2; or, K has not exceeded TK, then the following way is adopted: First step: determine which switch cabinet cable chamber has fire hazard, control the controllable one-way air valve 1 to close through the monitoring host, and monitor whether the value of R presents a downward trend within the set time after this moment, that is, R'<0, R' is the first derivative of R data, if yes, it is the first switch cabinet, if not, open the controllable one-way air valve 1; then close the controllable one-way air valve 2, and repeat the judgment until the switch cabinet cable chamber with fire hazard is found; Second step: evaluate the risk level of the switch cabinet: S=k1*SR+k2*SG1*k3*SG2+k4*SG3+k5*SG4; wherein, SR=10-(R-K) / K, if SR calculated is less than 0, then take SR=0; SG1: if G1>0, and the time is T1 seconds or more, SG1=0; otherwise, SG1=10; SG2: if G2>0, and the time is T1 seconds or more, SG2=0; otherwise, SG2=10; SG3: if G3>0, and the time is T1 seconds or more, SG3=0; otherwise, SG3=10; SG4: if G4>0, and the time is T1 seconds or more, SG4=0; otherwise, SG4=10; Third step: take corresponding measures according to the risk evaluation level.

2. The pyrolytic particle sensor-based switchgear fire early warning method according to claim 1, characterized in that, The monitoring host collects the data of pyrolysis particle and characteristic gas monitoring module, external environment monitoring module and air extraction module through 485 bus, and displays the monitoring data through the screen.

3. The pyrolytic particle sensor-based switchgear fire early warning method according to claim 1, characterized in that, The monitoring host is also connected with the controllable one-way air valve for controlling the conduction and closing of the air valve.

4. The pyrolytic particle sensor-based switchgear fire early warning method according to claim 1, characterized in that, The pyrolysis particle and characteristic gas monitoring module comprises a sealed box body, a pyrolysis particle sensor and a characteristic gas sensor.

5. The pyrolytic particle sensor-based switchgear fire early warning method according to claim 4, characterized in that, The sealed box body has an air inlet and an air outlet at both ends, and a sealing flange is installed on each of the air inlet and the air outlet, and the sealing flanges are connected with the gas guide pipe of the air extraction module; the pyrolysis particle sensor and the characteristic gas sensor are installed on the top of the sealed box body, and the pyrolysis particle sensor and the characteristic gas sensor communicate with the monitoring host through the bus.

6. The pyrolytic particle sensor-based switchgear fire early warning method according to claim 4, characterized in that, The characteristic gas sensor includes CO, C2H4, C2H6, CH3cl, and the range and resolution of the four gas sensors are the same.

7. The pyrolytic particle sensor-based switchgear fire early warning method according to claim 1, characterized in that, The gas extraction module further comprises a vacuum pump and a gas flow meter, the vacuum pump is connected with the gas flow meter, and the gas flow meter is connected with the gas guide pipe; during the monitoring process, the gas flow meter is used to monitor the flow of the extracted gas.

8. The pyrolytic particle sensor-based switchgear fire early warning method according to claim 1, characterized in that, The threshold values TR and TK are dynamically adjusted according to the temperature and humidity measured by the external environment monitoring module; the initial values of the state distribution weight coefficients are processed as follows: k1=0.6, k2=0.04, k3=0.08, k4=0.08, and k5=0.2; and the initial weight coefficients are obtained through expert evaluation and analytic hierarchy process, and can be dynamically corrected according to different scenes and actual conditions.

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