Foreign matter falling detection system for nuclear fuel pool

Abstract

The utility model provides a nuclear fuel pool foreign matter falling detection system, and belongs to the technical field of target detection. The system comprises an industrial camera, a millimeter wave radar, a grating sensor, a switch, an upper computer, a server and an alarm system. The industrial camera, the millimeter wave radar and the grating sensor can acquire different information from different heights and angles through reasonable installation and arrangement, so that multiple detection is carried out, and the detection range is large; the switch, the server and the upper computer receive the collected data and analyze and process the data; the alarm system is responsible for sending an alarm signal when the foreign matter falls. Compared with a manual inspection mode, the system can realize real-time detection and automatic alarm of the falling condition of the foreign matters in the nuclear fuel pool, so that the detection accuracy and efficiency are improved; compared with detection modes of other sensors, the system has the advantages that missing detection and false detection are avoided, the detection precision is higher, millimeter-level tiny foreign matters can be detected, interference of human factors is reduced, and safe operation of the nuclear fuel pool is guaranteed.

Description

Technical Field

[0001] The utility model belongs to the technical field of target detection and relates to a nuclear fuel pool foreign body falling detection system. Background Art

[0002] With the continuous development of technology, the safety and efficiency of nuclear power plants are constantly improving, and nuclear power generation has become an important clean energy generation method. Nuclear power plants convert nuclear energy into electrical energy through nuclear reactors with the help of nuclear fuel, and nuclear fuel usually has strong radiation, so the handling and storage of nuclear fuel is crucial. The function of the nuclear fuel pool is to store and load nuclear fuel elements, fuel rods, etc., and also to store used nuclear fuel elements. In the nuclear fuel pool, water or other coolants are usually filled inside to ensure the stability and safety of nuclear fuel, and nuclear fuel elements are placed on specially designed brackets or racks to ensure that they do not interfere with each other or produce dangerous reactions. At the same time, when an accident occurs in a nuclear power plant or an emergency shutdown is required, the nuclear fuel pool can provide emergency cooling and safe storage of nuclear fuel to prevent overheating of nuclear fuel from causing the nuclear reactor to go out of control. Therefore, the nuclear fuel pool plays an important role in safely protecting nuclear fuel and is one of the key components to ensure the safe and stable operation of nuclear power plants.

[0003] However, during the operation of nuclear power plants, foreign objects are prone to fall due to equipment aging, human negligence and other reasons. Foreign object falling events inside nuclear power plants, especially around nuclear fuel pools, will not only cause equipment failures, but also easily lead to safety accidents and even affect the normal operation of the entire nuclear power plant. Therefore, it is very important to effectively monitor and protect the nuclear fuel pools of nuclear power plants. At present, the traditional foreign object falling detection method mainly relies on manual inspection and equipment sensor detection, which has the problems of strong human subjectivity, limited detection range, low detection efficiency, and easy false detection; due to the wide coverage area of ​​the nuclear fuel pool, the high height above, and the large overall range, the detection of a single sensor is prone to missed detection; and the nuclear fuel pool is surrounded by various working equipment, and the overall structure is complex, making it difficult to detect its surroundings; and the working environment of the nuclear fuel pool is complex, with high temperature and strong radiation, which puts higher requirements on the stability and tolerance of the detection equipment; plus there are personnel working areas and a large number of sports equipment around, there are certain blind spots and interference, which will also cause certain difficulties for foreign object falling detection. Therefore, in order to improve the reliability, accuracy and detection efficiency of foreign object falling detection, the utility model proposes a nuclear fuel pool foreign object falling detection system. Utility Model Content

[0004] In order to solve the above problems existing in the prior art, the utility model provides an efficient detection system that can be applied to the interior of a nuclear power plant and around a nuclear fuel pool, and detects whether millimeter-level tiny foreign objects have fallen into a nuclear fuel pool in scenes with a large number of equipment and a complex environment. The system adopts a three-level hardware system of high-resolution industrial cameras, millimeter-wave radars, and grating sensors, and optimizes the arrangement of the three-level hardware systems. It can achieve detection of a large coverage area with a small number of sensors. It not only has high detection accuracy, fast detection speed and response time, and high detection efficiency, but also is simple to install and easy to use. It is suitable for situations that are difficult to detect with other single sensor systems, and also has a variety of development functions.

[0005] The technical solution adopted by the utility model is:

[0006] A nuclear fuel pool foreign body falling detection system, comprising an industrial camera 1, a millimeter wave radar 2, a grating sensor 3, a switch 4, a host computer 5 and a server 6;

[0007] The millimeter wave radar 2 is installed at a fixed height on the wall above the nuclear fuel pool; the industrial camera 1 is installed at a fixed position below the millimeter wave radar 2; the grating sensor 3 is installed at a position above the nuclear fuel liquid level and below the industrial camera 1;

[0008] The network communication interfaces of the industrial camera 1 and the millimeter-wave radar 2 are connected to the switch 4 via a gigabit network cable, the grating sensor 3 is connected to the switch 4 via an RS-485 communication line, the switch 4 is connected to the host computer 5 and the server 6 respectively via a gigabit network cable, and the host computer 5 is connected to the server 6 via a USB interface and a data cable.

[0009] In one of the embodiments, the millimeter-wave radar 2 is a first-level hardware system. Two millimeter-wave radars 2 are installed on the walls in all directions above the nuclear fuel pool, and the signal transmitting and receiving ports of the millimeter-wave radar 2 are perpendicular to the wall. The installation height is 18 to 19 meters above the liquid surface of the nuclear fuel pool. It is used to detect foreign objects at a height of 17 to 20 meters from the liquid surface and confirm whether there are objects within this range entering the range above the nuclear fuel pool.

[0010] In one embodiment, the distance between two millimeter-wave radars 2 on the same wall is 3-5 m, and the distance between each millimeter-wave radar 2 and the wall is 3-5 m.

[0011] In one of the embodiments, a plurality of industrial cameras equipped with industrial lenses are used as the second-level hardware system, and the second-level hardware system is divided into three subsystems according to the installation height. In each subsystem, two groups of industrial cameras are respectively installed on two opposite walls above the nuclear fuel pool, and the number and installation positions of the two groups of industrial cameras correspond one to one; the number and installation positions of industrial cameras in two adjacent subsystems are consistent, and the industrial cameras of the three-layer subsystem form a camera matrix, and the distance between each vertical column of industrial cameras in the matrix is ​​1~2.5m; the distance between each industrial camera and the wall is 1~2m.

[0012] In one of the embodiments, in the three-layer subsystem, the installation angle of the industrial cameras in the lower two layers is downward, so as to collect the overhead images of the liquid surface of the nuclear fuel pool and analyze the falling situation and specific location of foreign objects; the center line of the lens of the industrial camera in the lowest layer is 10°~20° with the wall, and the installation height is 5~6m above the liquid surface of the nuclear fuel pool; the center line of the lens of the industrial camera in the middle layer is 40°~60° with the wall, and the installation height is 6~7m above the liquid surface of the nuclear fuel pool; the distance between the industrial cameras in the lower two layers is 1~2m; the installation angle of the industrial camera in the top layer is upward, the center line of the lens is 40°~60° with the wall, and the installation height is 5~6m from the ceiling, so as to collect the upward images of the ceiling and analyze the trajectory of the falling foreign objects.

[0013] In one of the embodiments, the grating sensor 3 is a third-level hardware system, and a plurality of grating sensors 3 are provided and installed on the walls around the nuclear fuel pool to form an optical matrix; the transmitting end and the receiving end of the grating sensor 3 are perpendicular to the wall, and the installation height is 1 to 2 meters above the liquid surface of the nuclear fuel pool, which is used to assist in detecting foreign matter and prevent missed detection.

[0014] In one embodiment, it also includes an alarm system 7 and a display screen 8; the alarm system 7 is connected to the switch 4 via an RS-485 communication line, receives and sends out an alarm signal input by the switch 4, and displays relevant information on the display screen 8; the display screen 8 is connected to the alarm system 7 via a USB interface and a data cable, and also has a control panel.

[0015] In one of the embodiments, if any one of the industrial camera 1, the millimeter wave radar 2, and the grating sensor 3 detects a foreign object, an alarm signal is sent back and the alarm system is triggered.

[0016] In one embodiment, the industrial camera 1, millimeter wave radar 2, grating sensor 3, switch 4, host computer 5, server 6, alarm system 7, and display screen 8 are each independently powered and connected to the power supply through power cords.

[0017] Beneficial effects of the utility model: The utility model adopts a variety of sensors including millimeter-wave radar, industrial camera, grating sensor, etc. to collect different information from different heights and angles to perform multiple detections. The system structure is clear and the levels are distinct. The sensors of each subsystem have clear division of labor. Millimeter-wave radar is used to detect low-speed tiny foreign objects falling from a high place, and the process of foreign objects falling is captured by industrial cameras with different resolutions and frame rates. Finally, a fast-response grating sensor is used to detect high-speed moving objects that are about to enter the liquid. The utility model not only has a large overall detection range and a wide coverage area, but also has a reasonable distribution of the installation positions of each sensor, which avoids the problem of interference in the detection process without affecting the normal operation of other surrounding equipment in the nuclear power plant, and can achieve detection of a large coverage area with a small number of sensors; and the detection angle is relatively comprehensive, which solves the problems of strong human subjectivity and limited detection range in traditional methods, as well as the problems of difficulty in installation, low sensitivity, and susceptibility to human interference in the detection process of detection systems based on other sensors in complex scenes of nuclear fuel pools, and also solves the problems of small detection range, missed detection, false detection, poor stability, and low detection accuracy caused by the use of a single sensor; it not only improves the detection efficiency and detection accuracy, but also reduces the workload of manual inspection and reduces the detection cost. At the same time, the system can also realize the detection of millimeter-level tiny objects and real-time detection of foreign body falling events; the overall detection accuracy and detection efficiency are high, the detection speed and response time are fast, it has a variety of developable functions, and can also be used in conjunction with other equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the structure of the utility model.

[0019] Figure 2 It is a system block diagram of the utility model.

[0020] Figure 3 It is a schematic diagram of the three-level hardware system distribution of the utility model.

[0021] Figure 4 It is a side view schematic diagram of the single-sided imaging area coverage of an industrial camera.

[0022] Figure 5 It is a top-down diagram of the imaging area coverage of an industrial camera.

[0023] Figure 6 This is the millimeter-wave radar detection screen.

[0024] In the picture: 1 industrial camera, 2 millimeter wave radar, 3 grating sensor, 4 switch, 5 host computer, 6 server, 7 alarm system, 8 display screen. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the utility model more clear, the specific implementation methods of the utility model will be described in detail below with reference to the accompanying drawings.

[0026] like Figure 1 The present embodiment provides a nuclear fuel pool foreign body falling detection system, comprising an industrial camera 1, a millimeter wave radar 2, a grating sensor 3, a switch 4, a host computer 5, a server 6, an alarm system 7 and a display screen 8; wherein the industrial camera 1 is used to shoot and record real-time video of the nuclear fuel pool site, the millimeter wave radar 2 is used to detect whether there is a foreign body within the top range of the nuclear fuel pool, the grating sensor 3 is used to detect foreign bodies within a certain range above the liquid surface of the nuclear fuel pool, and the switch 4 is used for real-time communication and data transmission; the host computer 5 and the server 6 implement data storage and detection processing based on the existing method; the alarm system 7 is used to issue an alarm signal; the display screen 8 is used as a control panel to display alarm information; when any one of the industrial camera 1, the millimeter wave radar 2 and the grating sensor 3 detects a foreign body, the alarm signal is transmitted to the alarm system 7 through the switch 4, and the alarm system 7 issues an alarm and displays it on the display screen 8, thereby finally achieving the purpose of foreign body detection.

[0027] like Figure 1 and Figure 2 As shown, the nuclear fuel pool foreign body falling detection system includes an industrial camera 1, a millimeter wave radar 2, a grating sensor 3, a switch 4, a host computer 5, a server 6, an alarm system 7 and a display screen 8; wherein the millimeter wave radar 2 is installed at a fixed height on the wall above the nuclear fuel pool, the industrial camera 1 equipped with a high-resolution industrial lens is installed at a fixed position below the millimeter wave radar 2, and the grating sensor 3 is installed at a position above the nuclear fuel liquid level and below the industrial camera 1; the switch 4 is connected to the host computer 5 and the server 6 respectively through a gigabit network cable, and the host computer 5 is connected to the server 6 through a USB interface and a data cable; the network communication interfaces of the industrial camera 1 and the millimeter wave radar 2 are connected to the switch 4 through a gigabit network cable, and the grating sensor 3 is connected to the switch 4 through an RS-485 communication line. The alarm system 7 is connected to the switch 4 via an RS-485 communication line, and is composed of a buzzer, a diode, a control circuit, a display screen and other devices. The control circuit judges and processes the input data through a built-in logic judgment module. If an alarm signal from the switch 4 is received, the buzzer and the diode are triggered, and the relevant information is displayed on the display screen 8; the display screen 8 is connected to the alarm system 7 via a USB interface and a data cable, and is also equipped with a control panel to remind relevant personnel to pay attention and perform subsequent operations. The industrial camera 1, millimeter wave radar 2, grating sensor 3, switch 4, host computer 5, server 6, alarm system 7, and display screen 8 are each independently powered and connected to the power supply via power lines.

[0028] like Figure 3As shown, the millimeter-wave radar 2 at the highest point is the first-level hardware system; the industrial camera 1 at the second highest point is the second-level hardware system, which includes three layers of camera subsystems; and the grating sensor 3 at the lowest point is the third-level hardware system.

[0029] Figure 6 This is an image containing foreign objects detected by one of the millimeter-wave radars. The millimeter-wave radar is a first-level hardware system with high resolution and sensitivity for objects of millimeter size. It can detect low-speed moving objects falling from a height by transmitting and receiving millimeter-wave signals. Two millimeter-wave radars 2 are installed on the walls in each direction around the nuclear fuel pool. The installation angle is perpendicular to the wall and is installed 18m above the liquid surface of the nuclear fuel pool; the distance between the two millimeter-wave radars 2 in the same direction is 5m, and the distance between the millimeter-wave radar 2 and the wall is 3m.

[0030] Figure 4 and Figure 5 All of them are installation layout diagrams of industrial cameras in one of the embodiments of the utility model. The second-level hardware system is divided into three subsystems according to the installation height. Each subsystem contains 10 industrial cameras, and each group of five industrial cameras is installed on two opposite walls above the nuclear fuel pool, and the installation positions correspond to each other. The three-layer subsystem arranges 5 rows of industrial cameras on two walls to form a camera matrix. The distance between each vertical row of industrial cameras in the matrix is ​​2.26m. A part of the overlapping field of view is created between each row of cameras to take into account the imaging of a certain height area from the surface of the imaging area. The installation distance between each industrial camera and the wall is 1m. The two layers of industrial cameras at the bottom are down-looking cameras, used to collect the down-looking images of the nuclear fuel pool surface; among them, the lens centerline of the bottom layer industrial camera is 18.22° to the wall, and is installed 5m above the nuclear fuel pool surface; the lens centerline of the middle layer camera is 46.675° to the wall, and is installed 6m above the nuclear fuel pool surface, with a distance of 1m between the two layers of cameras; the top layer industrial camera is an up-looking camera, with a lens 46.675° to the wall, and is installed 6m from the top ceiling of the nuclear fuel pool, 8m away from the second layer industrial camera, used to collect the up-looking images of the ceiling. The down-looking camera is responsible for covering the field of view of the imaging area surface, and taking into account the monitoring range within 1m height from the imaging area surface, responsible for analyzing the falling situation and specific location of foreign objects. The blind area of ​​the downward camera is provided by the upward camera at the initial stage of the foreign object falling from the ceiling. At this time, the foreign object has just started to fall freely, and the speed is very low within the field of view of the upward camera. Therefore, the upward camera is sufficient to provide reliable continuous frame images of the falling foreign object and is responsible for analyzing the trajectory of the falling foreign object. When the foreign object falls to within 1 m of the surface of the imaging area, the downward camera will take continuous frame images before and after entering the water.

[0031] The grating sensor 3 is a third-level hardware system that can obtain information about an object at a very high response speed and detect the object by measuring the degree of reflection or shielding of the light emitted by the sensor. The grating sensor 3 is provided in multiple numbers and multiple grating sensors 3 are installed on the walls around the nuclear fuel pool to form an optical matrix; the transmitting end and the receiving end of the grating sensor are perpendicular to the wall and installed at a position 1m above the liquid surface of the nuclear fuel pool, responsible for monitoring whether there are foreign objects falling into the liquid surface of the nuclear fuel pool, realizing auxiliary detection, and preventing missed detection and false detection problems.

[0032] The above-mentioned embodiments are all preferred implementation methods of the utility model, and do not limit the utility model in other forms. Any technician familiar with the profession may use the above content to make changes or follow suit. However, any changes made to the above embodiments based on the essence of the method of the utility model without departing from the content of the solution in the utility model still fall within the scope of protection of the utility model.

Claims

1. Nuclear fuel pool foreign body falling detection system, characterized in that: Including industrial cameras, millimeter wave radars, grating sensors, switches, host computers and servers; The millimeter wave radar is installed at a fixed height on the wall above the nuclear fuel pool; the industrial camera is installed at a fixed position below the millimeter wave radar; the grating sensor is installed at a position above the nuclear fuel liquid level and below the industrial camera; The switch is connected to a host computer, a server, an industrial camera, a millimeter-wave radar and a grating sensor respectively, and the host computer is connected to the server.

2. The nuclear fuel pool foreign body falling detection system according to claim 1, characterized in that: The millimeter-wave radar is a first-level hardware system. Two millimeter-wave radars are installed on the walls in all directions above the nuclear fuel pool. The signal transmitting and receiving ports of the millimeter-wave radar are perpendicular to the wall. The installation height is 18 to 19 meters above the liquid surface of the nuclear fuel pool.

3. The nuclear fuel pool foreign body falling detection system according to claim 2, characterized in that: The distance between two millimeter-wave radars on the same wall is 3~5m, and the distance between each millimeter-wave radar and the wall is 3~5m.

4. The nuclear fuel pool foreign body falling detection system according to claim 1, characterized in that: Multiple industrial cameras equipped with industrial lenses are used as the second-level hardware system. The second-level hardware system is divided into three subsystems according to the installation height. In each subsystem, two groups of industrial cameras are installed on two opposite walls above the nuclear fuel pool, and the number and installation positions of the two groups of industrial cameras correspond one to one; the number and installation positions of industrial cameras in two adjacent subsystems are consistent, and the industrial cameras of the three-layer subsystem form a camera matrix. The distance between each vertical column of industrial cameras in the matrix is ​​1~2.5m; the distance between each industrial camera and the wall is 1~2m.

5. The nuclear fuel pool foreign body falling detection system according to claim 4, characterized in that: In the three-layer subsystem, the installation angles of the industrial cameras on the lower two layers are downward, wherein the center line of the lens of the industrial camera on the lowest layer is 10°~20° with the wall, and the installation height is 5~6m above the liquid surface of the nuclear fuel pool; the center line of the lens of the industrial camera on the middle layer is 40°~60° with the wall, and the installation height is 6~7m above the liquid surface of the nuclear fuel pool; the distance between the industrial cameras on the lower two layers is 1~2m; the installation angle of the industrial camera on the top layer is upward, the center line of the lens is 40°~60° with the wall, and the installation height is 5~6m from the ceiling.

6. The nuclear fuel pool foreign body falling detection system according to claim 1, characterized in that: The grating sensor is a third-level hardware system. A total of multiple grating sensors are arranged and installed on the walls around the nuclear fuel pool to form an optical matrix. The transmitting end and the receiving end of the grating sensor are perpendicular to the wall, and the installation height is 1 to 2 meters above the liquid surface of the nuclear fuel pool.

7. The nuclear fuel pool foreign body falling detection system according to claim 1, characterized in that: It also includes an alarm system and a display screen; the alarm system is connected to the switch, receives and sends out an alarm signal input by the switch, and displays relevant information on the display screen; the display screen is connected to the alarm system.

8. The nuclear fuel pool foreign body falling detection system according to claim 1, characterized in that: If any of the industrial cameras, millimeter-wave radars, and grating sensors detects a foreign object, an alarm signal will be sent back and the alarm system will be triggered.

9. The nuclear fuel pool foreign body falling detection system according to claim 1, characterized in that: The industrial camera, millimeter wave radar, grating sensor, switch, host computer, server, alarm system, and display screen are each independently powered and connected to the power supply through a power cord.

Images