Gas Leak Detection System

Abstract

To specify a leakage source of gas.SOLUTION: A gas leakage detection system 1 comprises: a detection unit 10 which can detect leakage of gas of a detection object in a detection area; a first imaging device 12 which is installed in the detection area and can image the inside of the detection area; a movable mechanism 14 which fixes the detection unit 10 and can change the detection direction of the detection unit 10; a storage unit 40; and a detection control unit 44. The coordinates in the first image generated by the first imaging device 12 and the detection position of the detection object of the detection unit 10 are associated with each other, and the object position indicating the position where it is assumed that there is a high possibility of gas leakage is specified on the basis of the first image. The detection control unit 44 controls the movable mechanism 14 so as to make the detection unit detect the presence / absence of gas leakage at the object position, and makes the storage unit 40 store the leakage position where the leakage is detected when the gas leakage is detected.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a gas leak detection system. [Background technology]

[0002] For example, Patent Document 1 discloses a technique for scanning a target space with a laser beam and detecting hydrogen gas in the target space based on the scattered light from the laser beam. In this technique, the detection result of hydrogen gas is displayed superimposed on a background image of the target space. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2007-232374 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a mode in which gas is detected throughout the entire target space, it is easy to grasp that gas is leaking, but it is difficult to identify the specific source of the gas leak.

[0005] In view of the above problems, an object of the present invention is to provide a gas leak detection system capable of identifying the source of a gas leak. [Means for solving the problem]

[0006] In order to solve the above problems, the gas leak detection system of the present invention includes a detection unit capable of detecting leakage of a detection target gas within a detection area, a first imaging device installed within the detection area and capable of imaging the detection area, a movable mechanism to which the detection unit is fixed and which can change the detection direction of the detection unit, A second imaging device fixed to the movable mechanism and capable of imaging within the detection area; and a display unit. A storage unit and a detection control unit are provided, and coordinates in a first image generated by a first imaging device, coordinates in a second image generated by the second imaging device;A detection position to be detected by the detection unit is associated with the target position, which indicates a position where it is assumed that there is a high possibility of gas leakage, and the detection control unit controls the movable mechanism to cause the detection unit to detect the presence or absence of gas leakage at the target position, and when gas leakage is detected, causes the leakage position where the leakage was detected to be stored in the storage unit. At the same time, an index that allows the leak position to be grasped is superimposed on the second image and displayed on the display unit. . In order to solve the above problems, the gas leak detection system of the present invention includes a detection unit capable of detecting leakage of a detection target gas within a detection area, a first imaging device installed within the detection area and capable of imaging the detection area, a movable mechanism to which the detection unit is fixed and which can change the detection direction of the detection unit, a storage unit, and a detection control unit. The check section and a coordinate in a first image generated by the first imaging device is associated with a detection position to be detected by the detection unit, and a target position indicating a position assumed to be highly likely to cause gas leakage is identified based on the first image; A detection route is set that defines consecutive target positions. The detection control unit controls the detection unit to detect the presence or absence of gas leakage at the target position. , and to detect along the detection route, A movable mechanism is controlled, and when a gas leak is detected, the leak position where the leak is detected is stored in a memory unit. The check section is provided in the middle of the detection route and is filled with a gas so as to be detectable. The detection control section performs self-diagnosis based on whether or not the gas is detected in the check section. . Effect of the Invention

[0010] According to the present invention, it is possible to identify the source of gas leakage. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic diagram showing the configuration of a gas leak detection system according to the present embodiment. [Diagram 2] FIG. 2 is a diagram showing an example of the first image. [Diagram 3] FIG. 3 is a diagram showing an example of a screen display of the display unit when no leakage of the detection target gas occurs. [Figure 4] FIG. 4 is a diagram showing an example of a screen display on the display unit when leakage of the detection target gas is detected. [Diagram 5]FIG. 5 is a flowchart illustrating the flow of operations of the detection control unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. The dimensions, materials, and other specific values ​​shown in the embodiment are merely examples for facilitating understanding of the invention, and do not limit the present invention unless otherwise specified. In this specification and drawings, elements having substantially the same functions and configurations are given the same reference numerals to avoid repeated explanations, and elements not directly related to the present invention are not shown.

[0013] 1 is a schematic diagram showing the configuration of a gas leak detection system 1 according to the present embodiment. The gas leak detection system 1 includes a detection unit 10, a first imaging device 12, a movable mechanism 14, a second imaging device 16, and a control device 18.

[0014] The detection unit 10 is configured to be able to detect leakage of a target gas within a predetermined detection area. Hereinafter, the target gas may be referred to as a target gas. The target gas is, for example, methane gas, but is not limited to methane gas and may be any gas. The detection area is, for example, a facility in which the target gas is used, but may be any location where leakage of the target gas may occur.

[0015] The detection unit 10 has a first laser emitting unit 20, a light receiving unit 22, and a second laser emitting unit 24. The first laser emitting unit 20 is capable of emitting a first laser 26. The first laser 26 is a sensing laser for detecting the target gas. Specifically, the first laser 26 is a laser having a wavelength (e.g., infrared) similar to the absorption wavelength of the target gas.

[0016] The light receiving unit 22 is capable of receiving the backscattered light of the first laser 26. The detection unit 10 detects the concentration of the target gas at the position irradiated with the first laser 26 based on the backscattered light of the first laser 26 received by the light receiving unit 22. For example, when the concentration of the target gas increases, the amount of the first laser 26 absorbed by the target gas increases, and the intensity of the backscattered light of the first laser 26 decreases. The light receiving unit 22 outputs the concentration of the target gas so that the concentration of the target gas increases as the intensity of the backscattered light received by the first laser 26 decreases. If the concentration of the target gas detected by the light receiving unit 22 is higher than a predetermined concentration, it is found that the target gas is leaking at the position irradiated with the first laser 26.

[0017] The second laser irradiation unit 24 is capable of irradiating the second laser 28 in the same direction as the first laser irradiation unit 20. The second laser 28 is, for example, a visible light laser. Here, the first laser 26 is, for example, an infrared laser, and is therefore difficult to visually recognize. The second laser irradiation unit 24 is provided to make the irradiation direction of the first laser 26, which is difficult to visually recognize, visible by substituting the second laser 28. In other words, the second laser 28 is a laser for indicating the irradiation position of the first laser 26.

[0018] The method of detecting the target gas is not limited to a laser method, but may be, for example, a method of detection based on sound waves or vibrations, or a method of aspirating gas within the detection area and analyzing the gas components.

[0019] The first imaging device 12 is fixedly installed within the detection area and is configured to be able to capture an image of the entire detection area, such as an area 30 indicated by a dashed-dotted rectangle in Fig. 1. The first imaging device 12 is installed, for example, on the top of a pillar within the detection area so as to overlook the detection area. The first imaging device 12 generates a first image capturing an image of the entire detection area.

[0020] The movable mechanism 14 is, for example, a camera platform, and is disposed above the first imaging device 12 in Fig. 1. The detection unit 10 is fixed to the movable mechanism 14. The movable mechanism 14 is configured to be able to change the detection direction of the detection unit 10. For example, the movable mechanism 14 can change the horizontal angle (azimuth) and the vertical angle (elevation).

[0021] The second imaging device 16 is configured to be able to capture an image of a part of the detection area. The second imaging device 16 captures an image with a narrower imaging range than the first imaging device 12, such as the area 32 shown by the dashed square in FIG. 1. This allows the second imaging device 16 to capture an image of a narrower range than the first imaging device 12 in an enlarged manner without reducing the resolution. The second imaging device 16 generates a second image capturing a part of the detection area. The second imaging device 16 is fixed to the movable mechanism 14 so that the imaging direction of the second imaging device 16 is the same as the detection direction of the detection unit 10. The movable mechanism 14 is configured to be able to change the detection direction of the detection unit 10 and the imaging direction of the second imaging device 16 in synchronization with each other.

[0022] The movable mechanism 14 is not limited to a camera platform, but may be any mechanism capable of changing the detection direction of the detection unit 10 and the imaging direction of the second imaging device 16 and identifying the detection direction. For example, the movable mechanism 14 may be a robot arm or a drone.

[0023] Also, the second imaging device 16 may be omitted. In such a case, the movable mechanism 14 may be, for example, a galvanometer mirror or a polygon mirror, as long as it is capable of changing the detection direction of the detection unit 10.

[0024] The control device 18 includes a storage unit 40, a display unit 42, and a detection control unit 44. The storage unit 40 is composed of, for example, a non-volatile storage element. The storage unit 40 stores detection results and the like. The display unit 42 can display the first image, the second image, the detection results, and the like under the control of the detection control unit 44.

[0025] The detection control unit 44 is a computer configured with semiconductor integrated circuits including a central processing unit (CPU), a ROM in which programs and the like are stored, and a RAM as a work area. The detection control unit 44 controls the entire gas leakage detection system 1. For example, the detection control unit 44 controls the detection direction of the detection unit 10 by controlling the movable mechanism 14. The operation of the detection control unit 44 will be described in detail later.

[0026] Here, in the gas leak detection system 1, coordinates in the first image generated by the first imaging device 12, coordinates in the second image generated by the second imaging device 16, and a detection position that is a detection target of the detection unit 10 are associated with each other. The coordinates in the first image, the coordinates in the second image, and the detection position may be associated with parameters such as azimuth and elevation of the movable mechanism 14. In other words, it is sufficient to be able to represent a substantially equivalent position before and after the coordinate transformation.

[0027] 2 is a diagram showing an example of the first image. In the gas leak detection system 1, a target position indicating a position where it is assumed that the target gas is likely to leak is specified based on the first image. The position where the target gas is likely to leak is, for example, the gas pipe 50, a flange at the end of the gas pipe 50, a valve provided in the gas pipe 50, etc., but is not limited to these and can be set arbitrarily.

[0028] When setting the target position, a first image is displayed on the display unit 42 as shown in Fig. 2. As shown by a black circle 52 in Fig. 2, the user sets a position such as a bent part of the gas pipe 50 in the first image as a representative target position. Then, the coordinates of the set target position are registered in the detection control unit 44.

[0029] When the user registers the coordinates of multiple representative target positions, a detection route is set to connect the registered target positions, as shown by arrow 54 in FIG. 2. The detection route includes the registered representative target positions, and defines a series of target positions that are assumed to have a high possibility of leakage of the target gas. The detection route is set, for example, along the gas pipe 50. The detection route may also be set across multiple gas pipes 50. The double circle 56 in FIG. 2 indicates an example of the start point of the detection route, and the triple circle 58 in FIG. 2 indicates an example of the end point of the detection route.

[0030] Note that the present invention is not limited to the embodiment in which the user sets the detection route by viewing the first image. For example, the detection control unit 44 may perform image analysis on the first image to extract a bent portion of the gas pipe 50, a flange at the end of the gas pipe 50, a valve provided in the gas pipe 50, and the like from the first image. Then, the detection control unit 44 may set a detection route using the extracted bent portion, flange, valve, and the like of the gas pipe 50 as representative target positions.

[0031] Once the setting of the target position is completed, the detection control unit 44 periodically executes a gas leakage detection process to detect leakage of the detection target gas. For example, the detection control unit 44 may execute gas leakage detection at any timing, such as once a day, once an hour, or once every 10 minutes.

[0032] When the gas leakage detection process is started, the detection control unit 44 controls the movable mechanism 14 to cause the detection unit 10 to detect the presence or absence of leakage of the detection target gas at the target position. More specifically, the detection control unit 44 controls the movable mechanism 14 to cause detection along the detection route indicated by the arrow 54 in Fig. 2 from the start point indicated by the double circle 56 in Fig. 2 to the end point indicated by the triple circle 58 in Fig. 2.

[0033] The detection control unit 44 determines that the target gas is leaking when the concentration of the target gas detected by the detection unit 10 along the detection route is equal to or greater than a predetermined value. The predetermined value is set to a value that makes it possible to distinguish between the general presence of the target gas within the detection area and the leakage of the target gas within the detection area.

[0034] 3 is a diagram showing an example of the screen display of the display unit 42 when no leakage of the target gas is occurring. The screen of the display unit 42 is divided into a coordinate display area 60, a concentration display area 62, and a second image display area 64.

[0035] The coordinate display area 60 displays each coordinate on the detection route. For example, the coordinate display area 60 may display the coordinates of a representative target position registered when the target position was set. The concentration display area 62 displays the concentration of the target gas detected by the detection unit 10 at the current coordinate on the detection route. The second image display area 64 displays the current second image generated by the second imaging device 16.

[0036] Fig. 4 is a diagram showing an example of the screen display of the display unit 42 when a leak of the detection target gas is detected. A circle 66 in the second image display area 64 in Fig. 4 indicates the leak position, and the cross-hatched area including the circle 66 indicates an area where the concentration of the detection target gas is high. In other words, the circle 66 is an indicator that makes it possible to grasp the leak position.

[0037] When a leakage of the detection target gas is detected, the detection control unit 44 causes the storage unit 40 to store the leakage position where the leakage was detected and the second image at the time when the leakage was detected.

[0038] Then, the detection control unit 44 causes an indicator capable of grasping the leakage position to be superimposed on the second image in the second image display area 64, as shown by a circle 66 in Fig. 4. At this time, the detection control unit 44 may cause an area where the concentration of the detection target gas is high to be displayed, as shown by a cross-hatched area including the circle 66. Furthermore, the detection control unit 44 may cause the background of the concentration display area 62 to be displayed in a display mode different from that when the detection target gas is not leaking, for example, in red, as exemplified by hatching in Fig. 4.

[0039] When a leak of the detection target gas is detected, the detection control unit 44 may notify the user by displaying the information on the display unit 42, but may also notify the user by an alarm sound or a warning light. When a leak of the detection target gas is detected, the detection control unit 44 may also transmit information about the occurrence of the leak and the location of the leak to, for example, a communication terminal of an administrator. In FIG. 4, an indicator of the leak location is displayed superimposed on the second image. However, the detection control unit 44 may display an indicator of the leak location superimposed on the first image.

[0040] Furthermore, even if a leak of the detection target gas is detected midway along the detection route, the detection control unit 44 performs the gas leak detection process up to the end point of the detection route.

[0041] In addition, even if a leak of the target gas is detected halfway along the detection route and the end point of the detection route is reached, the gas leak detection process may be performed again from the start point so that the change in the leak over time can be grasped.

[0042] Fig. 5 is a flowchart explaining the flow of the operation of the detection control unit 44. When a predetermined interrupt timing occurs in a predetermined control period, the detection control unit 44 executes the series of processes in Fig. 5. The predetermined control period can be set arbitrarily, for example, every day, every hour, every 10 minutes, etc.

[0043] When a predetermined interrupt timing occurs at a predetermined control period, the detection control unit 44 initializes the detection position to the start point of the detection route and starts detection along the detection route (S10). More specifically, the detection control unit 44 controls the movable mechanism 14 to move the irradiation direction of the first laser 26 from the direction toward the start point along the detection route. Next, the detection control unit 44 determines whether the detection position has reached the end point of the detection route (S11).

[0044] If the detection position has not reached the end point of the detection route (NO in S11), the detection control unit 44 acquires the concentration of the target gas, which is the detection result of the detection unit (S12). Then, the detection control unit 44 determines whether the target gas is leaking or not based on the acquired concentration of the target gas (S13). Specifically, the detection control unit 44 determines that the target gas is leaking when the concentration of the target gas is equal to or greater than a preset value.

[0045] When it is not determined that the target gas is leaking (NO in S13), the detection control unit 44 causes the acquired concentration to be displayed in the concentration display area 62 of the display unit 42, and causes the second image at the timing when the concentration was acquired to be displayed in the second image display area 64 of the display unit 42 (S14). Then, the detection control unit 44 returns to the process of step S11, and repeats the processes from step S11 onwards until the detection position reaches the end point of the detection route.

[0046] When it is determined in step S13 that the target gas is leaking (YES in S13), the detection control unit 44 stores the detection position of the target gas at the timing when the concentration was acquired in step S12 in the memory unit 40 as the leakage position (S20). The detection control unit 44 stores the second image at the timing when the concentration was acquired in step S12 in the memory unit 40 (S21). The detection control unit 44 generates a composite image in which an index that allows the leakage position to be grasped is superimposed on the second image (S22). Then, the detection control unit 44 displays the acquired concentration in the concentration display area 62 of the display unit 42, and displays the composite image in the second image display area 64 of the display unit 42 (S14). Then, the detection control unit 44 returns to the process of step S11, and repeats the process from step S11 onwards until the detection position reaches the end point of the detection route.

[0047] In the example of Fig. 5, when the detection position reaches the end point of the detection route, the detection control unit 44 temporarily ends the gas leakage detection process and waits until the next predetermined interrupt timing. However, when the detection position reaches the end point of the detection route, the detection control unit 44 may initialize the detection position to the start point of the detection route and resume the gas leakage detection process shown in Fig. 5 without delay. In other words, the detection control unit 44 may continuously repeat the gas leakage detection process.

[0048] As described above, in the gas leak detection system 1 of this embodiment, a target position indicating a position where the target gas is likely to leak is specified based on the first image. Then, the detection control unit 44 of this embodiment controls the movable mechanism 14 to cause the detection unit 10 to detect the presence or absence of leakage of the target gas at the target position, and when leakage of the target gas is detected, causes the leakage position where the leakage was detected to be stored in the memory unit.

[0049] As a result, the gas leak detection system 1 of this embodiment does not include detection results from extraneous space within the detection area, and detects only target locations where the target gas is likely to leak, making it possible to identify the source of the target gas leakage.

[0050] Furthermore, in the gas leak detection system 1 of this embodiment, detection is limited to target positions assumed to have a high probability of leaking the target gas, compared to a mode in which a wide space including extra space within the detection area is scanned, thereby reducing the processing load on the detection control unit 44.

[0051] Furthermore, in the gas leak detection system 1 of this embodiment, the coordinates in the first image, the coordinates in the second image, and the detection position are associated with each other. Therefore, in the gas leak detection system 1 of this embodiment, it is possible to identify a leakage source that reflects the coordinates in the depth direction of the detection area based on the installation position of the detection unit 10. Therefore, in the gas leak detection system 1 of this embodiment, maintenance to deal with leakage can be performed quickly.

[0052] In the gas leak detection system 1 of this embodiment, a predetermined check section may be provided midway along the detection route. The check section is formed, for example, of a hollow container or the like, and is a member in which the target gas is sealed in a detectable manner. An exposed section such as a glass window is provided in a part of the container of the check section. The exposed section is formed of a material that allows the first laser 26 to penetrate into the check section while preventing the target gas in the check section from leaking out of the check section. The size of the exposed section is smaller than the width of the target object, such as the gas pipe 50, on the detection route.

[0053] In a configuration in which such a check section is provided, the detection control section 44 intentionally detects the target gas in the check section through the exposed section. Then, the detection control section 44 may perform self-diagnosis as to whether the gas leakage detection process is being performed normally (in other words, the presence or absence of an abnormality in the gas leakage detection process) based on whether the target gas in the check section is detected. If the gas leakage detection process is being performed normally along the detection route, the detection control section 44 detects the target gas in the check section. However, if the target gas in the check section cannot be detected, it can be recognized that the gas leakage detection process along the detection route is no longer being performed, and the movable mechanism 14 can be calibrated. In addition, it is also possible to discover a malfunction of the movable mechanism 14 or the detection section 10. In addition, since the exposed section of the check section is smaller than the width of the target object such as a gas pipe, it is possible to improve the accuracy of discovering a malfunction when the actual detection route deviates from the normal detection route.

[0054] Although the preferred embodiment of the present invention has been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such an embodiment. It is clear that a person skilled in the art can think of various modifications or alterations within the scope of the claims, and it is understood that these also naturally belong to the technical scope of the present invention. [Explanation of symbols]

[0055] 1. Gas leak detection system 10. Detection unit 12 First imaging device 14 Movable mechanism 16 Second imaging device 40 Storage section 42 Display section 44 Detection control section

Claims

1. A detection unit capable of detecting leakage of a detection target gas within a detection area; A first imaging device that is installed within the detection area and is capable of imaging the detection area; a movable mechanism to which the detection unit is fixed and capable of changing a detection direction of the detection unit; a second imaging device fixed to the movable mechanism and capable of imaging an image within the detection area; A display unit; A storage unit; A detection control unit; Equipped with coordinates in a first image generated by the first imaging device, coordinates in a second image generated by the second imaging device, and a detection position that is a detection target of the detection unit are associated with each other; a target position indicating a position where it is assumed that the gas is likely to leak is identified based on the first image; The detection control unit is controlling the movable mechanism to cause the detection unit to detect the presence or absence of gas leakage at the target position; A gas leak detection system that, when a gas leak is detected, stores the location of the detected leak in the memory unit and displays an indicator that allows the location of the leak to be grasped on the display unit, superimposed on the second image.

2. A detection unit capable of detecting leakage of a detection target gas within a detection area; A first imaging device that is installed within the detection area and is capable of imaging the detection area; a movable mechanism to which the detection unit is fixed and capable of changing a detection direction of the detection unit; A storage unit; A detection control unit; The check section and Equipped with coordinates in a first image generated by the first imaging device and a detection position to be detected by the detection unit are associated with each other; a target position indicating a position where it is assumed that the gas is likely to leak is identified based on the first image; A detection route is set that defines the target positions consecutively, The detection control unit is controlling the movable mechanism to cause the detection unit to detect the presence or absence of the gas leakage at the target position and along the detection route; When a gas leak is detected, a leak position where the leak is detected is stored in the memory unit; the check section is provided midway along the detection route, and the gas is sealed therein in a detectable manner; The detection control unit performs self-diagnosis based on whether the gas is detected in the check unit.

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