KR102777699B1 - Dual functional Fiber Optic Distribution Temperature Measurement System - Google Patents

Abstract

The present invention relates to a dual-function optical fiber distributed temperature measurement system. The disclosed dual-function optical fiber distributed temperature measurement system is a dual-function optical fiber distributed temperature measurement system that implements functions for rapid temperature measurement and precise temperature measurement using a fire-fighting optical fiber distributed temperature measurement device, comprising: at least one fire detection optical cable for fire detection; a fire-fighting optical fiber distributed temperature measurement device that is connected to the fire detection optical cable and measures temperature by averaging Raman scattered light among scattered light generated from the optical fiber; at least one precision measurement optical cable for precise temperature measurement; an optical switch that connects the fire-fighting optical cable and the precision measurement optical cable and selectively switches the precision measurement optical cable; a fire receiver that receives the temperature measurement result of the fire-fighting optical fiber distributed temperature measurement device and determines whether there is a fire; an operating computer that averages and processes the temperature measurement results measured for a predetermined period of time through the precision measurement optical cable to output a precise temperature in order to obtain the precise temperature measurement result; and a data output of the fire-fighting optical fiber distributed temperature measurement device is shared with the fire receiver and the operating computer, and is transmitted to the optical switch from the operating computer. A dual-function optical fiber distributed temperature measurement system is provided, characterized by including a hub for connecting a control signal to an optical switch. According to the present invention, a dual-function optical fiber distributed temperature measurement system can be provided that can simultaneously implement the functions of fire detection as well as accurate temperature measurement by using a fire-fighting optical fiber distributed temperature measurement device that can detect temperature changes around an optical fiber as quickly as possible, in a system designed for cases where temperature measurement for two purposes, namely fire detection and precise temperature measurement, is simultaneously required.

Description

Dual functional Fiber Optic Distribution Temperature Measurement System

The present invention relates to a dual-function optical fiber distributed temperature measurement system, and more specifically, to a dual-function optical fiber distributed temperature measurement system capable of performing rapid fire detection and precise temperature measurement simultaneously using a fire-fighting optical fiber distributed temperature measurement device.

The material described in this section merely provides background information for the present embodiment and does not constitute prior art.

In general, to measure the temperature in multiple locations along a wide area or long distance, multiple temperature sensors must be installed and each temperature sensor must be connected to a central data collection device using a communication network. To measure the temperature in this way, temperature sensors must be installed in multiple locations, power must be supplied, and a communication network must be built, which costs a lot of money and takes a lot of time. In addition, it is difficult to install in environments with strong electromagnetic waves or where there is a risk of flooding. In environments with a high risk of explosion, installing an electrically operated temperature sensor itself can cause a fire. A sensor that utilizes optical fibers to solve these problems has been commercialized. An optical fiber sensor is a sensor that receives scattered light generated within an optical fiber by irradiating a laser pulse light onto an optical cable for the sensor at one end of an optical fiber that is several to several tens of kilometers long, and then obtains measurements of temperature, pressure, strain, etc. around the optical fiber at regular intervals. These optical fiber sensors can be used to replace sensors that would otherwise need to be installed at multiple locations with a single optical fiber, reducing the time and cost required for sensor installation. They are also less affected by surrounding electromagnetic waves, increasing the reliability and stability of measured values. They can also be used in environments with a high risk of explosion or submersion.

Fiber optic distributed temperature measurement devices are used for various purposes, but are mainly used for two purposes: firefighting, which measures temperature changes in a short period of time, such as fire monitoring, and precision temperature measurement, which measures temperature accurately over a sufficient period of time.

Conventionally, two types of fiber optic distributed temperature measuring devices have been used, each for its intended use. That is, fiber optic distributed temperature measuring devices for firefighting, which measure temperature in a short period of time to detect fire, and industrial fiber optic distributed temperature measuring devices, which measure for a longer period of time to detect accurate temperatures, are commercialized as different products. Fiber optic distributed temperature measuring devices for firefighting have a limitation on the measurement time, so the number of connectable optical cables is limited to one or a maximum of two, but industrial fiber optic distributed temperature measuring devices, which have no limitation on the measurement time, have no limitation on the number of connectable optical cables.

Although there are two types of fiber optic distribution temperature measuring devices depending on the purpose, in some cases, a fire-fighting fiber optic distribution temperature measuring device must be installed in one location by the Fire Service Act, but in other cases, an industrial fiber optic distribution temperature measuring device is needed to prevent fire by checking for overheating before a fire through precise temperature measurement. For example, places such as underground power tunnels and communication tunnels are subject to significant damage in the event of a fire, so the Fire Service Act requires the installation of a fire-fighting fiber optic distribution temperature measuring device. However, if the temperature of the power cables in the power tunnels and communication tunnels can be precisely measured with an industrial fiber optic distribution temperature measuring device, it is possible to detect overheating before a fire and take preventive measures.

The conventional optical fiber distribution temperature measuring device had the problem that a fire-fighting optical fiber distribution temperature measuring device and an industrial optical fiber distribution temperature measuring device had to be installed separately for each purpose.

Accordingly, in order to overcome the limitations of conventional technologies, the present invention proposes a dual-function optical fiber distributed temperature measurement system that enables two measurements of not only fire monitoring but also precise temperature measurement using a fire-fighting optical fiber distributed temperature measurement device.

Korean Patent Publication No. 10-1356986, published on November 20, 2013 (Title: Raman sensor system for optical fiber distribution temperature measurement) Korean Patent Publication No. 10-1634679, published on June 29, 2016 (Title: Fire detection system using optical sensor linear detector) Korean Patent Publication No. 10-2023-0045699, published on April 5, 2023 (Title: Fiber optic sensor system for temperature and vibration measurement)

The present invention has been proposed to solve the problems of the prior art described above, and is a system designed for cases where temperature measurement for two purposes, namely fire detection and precise temperature measurement, is required at the same time. The main purpose of the present invention is to provide a dual-function optical fiber distributed temperature measurement system that can simultaneously implement the functions of fire detection as well as precise temperature measurement by using a fire-fighting optical fiber distributed temperature measurement device that can detect temperature changes around an optical fiber as quickly as possible.

The problems to be solved by the present invention are not limited to those mentioned above, and other problems to be solved that are not mentioned will be clearly understood by a person having ordinary skill in the art to which the present invention belongs from the description below.

In order to achieve the above-mentioned object, one aspect of the present invention is a dual-function optical fiber distributed temperature measurement system having functions for rapid temperature measurement and precise temperature measurement using a fire-fighting optical fiber distributed temperature measurement device, the system comprising: at least one fire detection optical cable for detecting fire; a fire-fighting optical fiber distributed temperature measurement device connected to the fire detection optical cable and measuring temperature by averaging Raman scattered light among scattered light generated from the optical fiber; at least one precision measurement optical cable for precise temperature measurement; an optical switch connecting between the fire detection optical cable and the precision measurement optical cable and selectively switching the precision measurement optical cable; a fire receiver receiving the temperature measurement result of the fire-fighting optical fiber distributed temperature measurement device and determining the presence or absence of a fire; an operating computer averaging the temperature measurement results measured for a predetermined period of time through the precision measurement optical cable to output a precise temperature in order to obtain the precise temperature measurement result; And the present invention provides a dual-function optical fiber distribution temperature measurement system, characterized by including a hub for sharing data output of the optical fiber distribution temperature measurement device for firefighting with the fire receiver and the operating computer, and connecting a control signal for the optical switch from the operating computer to the optical switch.

When using two optical cables for fire detection, one cable can be used as a first optical cable for fire detection, and the other can be used as a second optical cable for fire detection input to the optical switch.

When only one of the above fire detection optical cables is used, the fire detection optical cable can be used directly as a precision measurement optical cable without the above optical switch.

When using only one optical cable for fire detection, an optical switch with two or more channels can be used.

The above fire-fighting optical fiber distribution temperature measuring device has a minimum measurement time t for outputting the temperature, and can be expressed by the relationship between the fire detection time T1 stipulated in the Fire Service Act and T1 = nt (n is an integer).

The above fire-fighting optical fiber distribution temperature measuring device can be expressed by the relationship T2 = N * T1 (N is an integer), where the measuring time for precise temperature measurement is T2.

When using two of the above fire detection optical cables, if the measurement time of the above fire-fighting optical fiber distribution temperature measuring device satisfying the conditions defined in the Fire Service Act is T1 per optical cable, the first fire detection optical cable can be measured for T1 hour, the second fire detection optical cable can be measured for T1 hour, and then the fire detection optical cable can be measured again in this order.

The above operating computer receives, through the hub, temperature information of one precision measurement optical cable connected through the optical switch and the second fire detection optical cable among the temperature measurement results of the fire-fighting optical distribution temperature measuring equipment, and, in order to obtain a precision temperature measurement result, collects the temperature measurement results of the one precision measurement optical cable measured for T1 time a predetermined number of times and performs an average process to output a precision temperature.

The above operating computer collects the temperature measurement results of the one precision measurement optical cable a predetermined number of times, averages them to output a precise temperature, and then controls the optical switch to collect the temperature of another precision measurement optical cable, and can repeatedly perform the temperature collection and output operations for all precision measurement optical cables connected to the optical switch.

The above fire receiver can determine whether there is a fire by only receiving the temperature measurement result of the first fire detection optical cable from the fire-fighting optical distribution temperature measuring device, and output an alarm if the measurement result determines that there is a fire.

According to the dual-function optical fiber distributed temperature measurement system of the present invention, there is an effect in that a dual-function optical fiber distributed temperature measurement system can be provided that can simultaneously implement the functions of fire detection as well as accurate temperature measurement by using a fire-fighting optical fiber distributed temperature measurement device that can detect temperature changes around an optical fiber as quickly as possible.

The effects obtainable from the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art to which the present invention belongs from the description below.

The accompanying drawings, which are incorporated in and are intended to aid in the understanding of the present invention and are intended to be a part of the detailed description, provide embodiments of the present invention and, together with the detailed description, serve to explain the technical features of the present invention.
Figure 1 is a diagram illustrating input light and scattered light used in an optical fiber sensor.
Figure 2 is a diagram illustrating the wavelength-dependent light intensity characteristics of Raman scattered light.
FIG. 3 is a drawing illustrating the configuration of a dual-function optical fiber distribution temperature measurement system according to one embodiment of the present invention.
FIG. 4 is a drawing illustrating the configuration of a dual-function optical fiber distribution temperature measurement system according to another embodiment of the present invention.
FIG. 5 is a drawing illustrating a timing diagram of a dual-function optical fiber distributed temperature measurement system according to one embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The detailed description set forth below with the accompanying drawings is intended to explain exemplary embodiments of the present invention and is not intended to represent the only embodiments in which the present invention may be practiced. The following detailed description includes specific details in order to provide a thorough understanding of the present invention. However, one of ordinary skill in the art will appreciate that the present invention may be practiced without these specific details.

In some cases, to avoid obscuring the concept of the present invention, well-known structures and devices may be omitted or illustrated in block diagram format focusing on the core functions of each structure and device.

Throughout the specification, when a part is said to "comprising" or "including" a certain component, this does not mean that other components are excluded, but rather that other components can be included, unless otherwise specifically stated. In addition, terms such as "part," "unit," "module," etc. described in the specification mean a unit that processes at least one function or operation, which may be implemented by hardware, software, or a combination of hardware and software. In addition, "a" or "an," "one," "the," and similar related words may be used in the context of describing the present invention (especially, in the context of the claims below) to include both the singular and the plural, unless otherwise indicated herein or clearly contradicted by the context.

In describing embodiments of the present invention, if it is judged that a detailed description of a known function or configuration may unnecessarily obscure the gist of the present invention, the detailed description will be omitted. In addition, the terms described below are terms defined in consideration of functions in the embodiments of the present invention, and these may vary depending on the intention or custom of the user or operator. Therefore, the definitions should be made based on the contents throughout this specification.

Each component in the drawings of the present invention is independently depicted to indicate different characteristic functions in the dual-function optical fiber distributed temperature measurement system, and does not mean that each component is composed of separate hardware or a single software component. That is, each component is listed and included as a separate component for convenience of explanation, and at least two components among each component may be combined to form a single component, or one component may be divided into multiple components to perform functions, and such integrated and separated embodiments of each component are also included in the scope of the present invention as long as they do not deviate from the essence of the present invention.

In addition, some components may not be essential components that perform essential functions in the present invention, but may be optional components that are merely used to improve performance. The present invention may be implemented by including only essential components for implementing the essence of the present invention, excluding components that are merely used to improve performance, and a structure that includes only essential components, excluding optional components that are merely used to improve performance, is also included in the scope of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the attached drawings.

Figure 1 is a diagram illustrating input light and scattered light used in an optical fiber sensor.

When a light pulse is input into an optical fiber, a weak amount of light returns to the input side due to scattering that occurs when the light collides with the glass grid component within the optical fiber.

Using the measurement principle of the OTDR (Optical Time Domain Reflectometer), since the speed of light inside the optical fiber is known, the location where the scattered light occurred can be calculated by measuring the time it takes for the scattered light to return.

In addition, among the scattered light returning to the input side, there is Raman scattered light that has a wavelength component different from the wavelength of the input light, and by measuring the intensity of these two wavelengths, the ambient temperature of the optical fiber can be calculated.

For reference, the scattered light from the optical fiber used in the optical fiber sensor includes Rayleigh scattered light, Raman scattered light, and Brillouin scattered light. Rayleigh scattered light is used to find the location of loss or short circuit in the optical fiber, Raman scattered light is used to measure the temperature around the optical fiber, and Brillouin scattered light is used to measure the strain in the optical fiber.

Figure 2 is a diagram illustrating the wavelength-dependent light intensity characteristics of Raman scattered light.

Raman scattered light is divided into anti-Stokes light with a shorter wavelength than the incident light and Stokes light with a longer wavelength than the incident light. While the amplitude of Stokes light changes little with changes in the temperature surrounding the optical fiber, the amplitude of anti-Stokes light changes sensitively with changes in the temperature surrounding the optical fiber. Therefore, by comparing and analyzing the light quantities of Stokes light and anti-Stokes light, the temperature surrounding the optical fiber can be calculated.

A device that measures temperature using this Raman scattered light is called an optical fiber distributed temperature measuring device. This device inputs a laser pulse into an optical fiber for sensing, and receives only the Raman scattered light (Stokes light and anti-Stokes light) among the backscattered light generated from the optical fiber for sensing, converts it into an electrical signal, processes the signal to convert it into digital data, and measures and averages the digital data of the Raman scattered light received at the same optical fiber location multiple times, and calculates the ambient temperature of the corresponding optical fiber location according to a predetermined algorithm using the ratio of the average value of the Stokes light and the average value of the anti-Stokes light.

Additionally, the position of the optical fiber where the temperature-calculated Raman scattered light is generated can be calculated using the time and light speed it takes for the Raman scattered light to return to the measuring device after the laser pulse light is incident.

The optical fiber distributed temperature measuring device that operates on this principle is used for various purposes, and is mainly used for two purposes. There is a firefighting purpose that measures temperature changes in a short period of time, such as fire monitoring, and a precision temperature measurement purpose that measures the temperature precisely over a sufficient period of time. Since the amount of Raman scattered light generated in the original optical fiber is only about one millionth of the incident light, the size of the electrical signal of the Raman scattered light (hereinafter referred to as the “Raman signal”) is very small and smaller than the random noise of the electronic circuit, so the temperature cannot be calculated directly without repeated measurements for averaging. Therefore, the optical fiber distributed temperature measuring device uses a noise filter circuit and minimizes the influence of random noise by acquiring as many Raman signals as possible and then averaging the acquired Raman signals. The greater the number of averaging times, the less the influence of random noise, which can improve the accuracy of the temperature value. However, if the number of averaging times is increased to improve the measurement accuracy, the temperature measurement time becomes longer. Therefore, the temperature accuracy and measurement time must be appropriately selected according to the purpose of using the optical fiber distributed temperature measuring device.

As an example of application, when installed along a power cable, the temperature of the entire power cable is measured at regular intervals to predict the transmittable power capacity, and it can be used to detect the location of partial high temperature generation caused by deterioration of the power cable. In this case, in order to determine overheating, the temperature must be measured precisely over a long period of time. (Hereinafter, an optical fiber distributed temperature measuring device for such precise temperature measurement is referred to as an “industrial optical fiber distributed temperature measuring device”). Another example of application is to use it for fire detection in buildings, tunnels, utility tunnels, or power tunnels where power cables are installed.

Since a fire detection device must detect the occurrence and location of a fire in real time rather than the accuracy of the fire temperature and issue an alarm and respond as quickly as possible, the fire detection time is limited by the Fire Service Act. (Hereinafter, the fiber optic distributed temperature measuring device for fire detection is referred to as a “fiber optic distributed temperature measuring device for firefighting.” Compared to the temperature measurement results of a fiber optic distributed temperature measuring device for firefighting, which are output quickly but have a large deviation from the actual temperature, the temperature measurement results of an industrial fiber optic distributed temperature measuring device take longer to output but have a much smaller deviation from the actual temperature.)

Previously, two types of fiber-optic distributed temperature measuring devices were used, each for its intended use. That is, fiber-optic distributed temperature measuring devices for firefighting, which measure temperature in a short period of time to detect fire, and industrial fiber-optic distributed temperature measuring devices, which measure for a longer period of time to detect accurate temperatures, were commercialized as different products. Fiber-optic distributed temperature measuring devices for firefighting have a limitation on the measurement time, so the number of connectable optical cables is limited to one or a maximum of two, but industrial fiber-optic distributed temperature measuring devices, which have no limitation on the measurement time, have no limitation on the number of connectable optical cables.

Although there are two types of fiber optic distribution temperature measuring devices according to the purpose, in some cases, a fiber optic distribution temperature measuring device for firefighting must be installed in one place by the Fire Service Act, but an industrial fiber optic distribution temperature measuring device is also needed to prevent fire by checking the overheating condition before a fire through a separate, precise temperature measurement. For example, in places such as underground power and communication tunnels, the damage is great in case of a fire, so the Fire Service Act requires the installation of a fiber optic distribution temperature measuring device for firefighting.

If the temperature of power cables in power or communication facilities can be precisely measured using an industrial fiber-optic distribution temperature measuring device, it is possible to detect overheating before a fire occurs and take preventive measures. However, in the case of conventional technology, there was a problem that a fire-fighting fiber-optic distribution temperature measuring device and an industrial fiber-optic distribution temperature device had to be installed separately for this purpose.

Hereinafter, an embodiment of a dual-function optical fiber distribution temperature measurement system of the present invention for solving problems in the prior art will be described in detail.

The components included in the description of the invention of this specification can be configured to operate individually or in combination.

FIG. 3 is a drawing illustrating the configuration of a dual-function optical fiber distribution temperature measurement system according to one embodiment of the present invention.

A dual-function optical fiber distribution temperature measurement system (100) according to one embodiment of the present invention may include a fire-fighting optical fiber distribution temperature measurement device (1), a fire detection optical cable (2), an optical switch (3), a precision measurement optical cable (4), an operating computer (5), a fire receiver (6), and a hub (7), as shown in FIG. 3.

The optical fiber distribution temperature measuring device (1) is a device that measures temperature by averaging Raman scattered light among scattered light generated from an optical fiber, and the minimum measurement time for outputting the temperature is determined.

If this minimum measurement time is t, the temperature measurement time per optical cable is determined by the condition that the fire detection time stipulated by the fire service law is satisfied for the optical fiber distribution temperature measuring device (1). If this time is T1, the relationship with the minimum measurement time is T1 = nt, which can be expressed as n times (integer multiple) of the minimum measurement time (t).

In addition, in cases where the temperature must be measured precisely, a longer measurement time is required. In this case, if the measurement time for the case where the temperature must be measured precisely is T2, it can be set to N times (integer multiple) of the measurement time T1 of the fire-fighting optical fiber distribution temperature measuring device, as T2 = N * T1.

The measurement time of a typical fire-fighting optical fiber distribution temperature measuring device is within several seconds, and the measurement time of an industrial optical fiber distribution temperature measuring device is from several tens of seconds to several minutes. When two optical cables for fire detection are used, if the measurement time of a fire-fighting optical fiber distribution temperature measuring device (1) that satisfies the conditions defined in the Fire Service Act is T1 per optical cable, the first fire-detection optical cable (21) is measured for T1 hour, the second fire-detection optical cable (22) is measured for T1 hour, and then the first fire-detection optical cable (21) is measured again, and this is repeated in this order.

When two optical cables for fire detection are used as in Fig. 3, the first optical cable for fire detection (21) is used for fire detection, the remaining second optical cable for fire detection (22) is input to the optical switch (3), and the optical cable connected to the output of the optical switch (3) is used as an optical cable (4) for precision measurement.

In Fig. 3, an optical cable (4) for precision measurement is shown as an example with four (41), (42), (43), (44) and an optical switch (3) having four output ports, but the number of these four is only an example and is not limited thereto.

For example, in the case where only one optical cable (2) for fire detection is used, the optical switch (3) can be omitted as shown in Fig. 4 and the optical cable (2) for fire detection can be used directly as an optical cable for precision measurement, or the optical switch (3) can be used as an optical switch with two or more channels.

The operating computer (5) receives temperature information of one precision measurement optical cable (41) connected through the second fire detection optical cable (22) and the optical switch (3) from among the temperature measurement results of the fire-fighting optical distribution temperature measuring equipment (1) through the hub (7), and in order to obtain a precise temperature measurement result, it collates the temperature measurement results of one precision measurement optical cable (41) measured for T1 time for a set number of times (set to N times), averages them, and outputs a precise temperature.

Thereafter, the temperature of another precision measurement optical cable (42) is collected by controlling the optical switch (3). The above operation is repeatedly performed for all precision measurement optical cables connected to the optical switch (3).

The fire receiver (6) receives only the temperature measurement result of the first fire detection optical cable (21) from the fire-fighting optical distribution temperature measuring device (1) to determine whether there is a fire, and outputs an alarm if the measurement result determines that there is a fire.

The hub (7) shares the data output of the fire-fighting optical fiber distribution temperature measuring device with the fire receiver (6) and the operating computer (5), and connects the control signal for the optical switch (3) from the operating computer (5) to the optical switch (3).

FIG. 4 is a drawing illustrating the configuration of a dual-function optical fiber distribution temperature measurement system according to another embodiment of the present invention.

Figure 4 is a configuration diagram illustrating a case where only one optical cable for fire detection is connected to a fire-fighting optical fiber distribution temperature measuring device (1).

In this case, the temperature information measured by the fire-fighting optical fiber distribution temperature measuring device (1) is transmitted to the fire receiver (6) through the hub (7), and then transmitted to the operating computer (5).

If the temperature information measured for firefighting needs to be measured N more times to calculate the desired level of precision, the operating computer (5) measures the received temperature information repeatedly a preset number of N times and then averages it to calculate the precise temperature result value.

In general, the role of an operating computer used in an industrial optical fiber distribution temperature measurement system that performs precision temperature measurement is played by an operating computer (5) in the dual-function optical fiber distribution temperature measurement system (100) according to the present invention.

The role of the operating computer (5) is to receive temperature data, schematically represent the location where the sensor optical cable is installed, and quickly confirm the location by indicating the location where abnormal temperature occurs with the actual distance on the field drawing rather than the length of the optical fiber. Various alarm criteria can be set for detecting abnormal temperature, and in some cases, past temperature measurement results can be stored in a database for confirmation.

In addition to the basic fire detection function of the fire-fighting optical fiber distribution temperature measuring device (1), a dual-function optical fiber distribution temperature measuring system can be configured by adding an N-times averaging function per channel through software from an operating computer (5) to an optical fiber (4) for precision measurement connected to an optical switch (3).

FIG. 5 is a drawing illustrating a timing diagram of a dual-function optical fiber distributed temperature measurement system according to one embodiment of the present invention.

The top row in Fig. 5 explains the operation of the fire-fighting optical fiber distribution temperature measuring device (1). The first fire detection optical cable (21) and the second fire detection optical cable (22) alternately perform repeated measurements with a T cycle.

Among them, the measurement results of the first fire detection optical cable (21) are transmitted to the fire receiver (6) to monitor whether there is a fire.

The second row of Fig. 5 explains the operation of the optical switch (3), where the second fire detection optical cable (22) is connected to the input of the optical switch (3) and the optical cable (4) for precision measurement is connected sequentially.

The initial connection is connected to a precision measurement optical cable (41), so that when the fire-fighting optical fiber distribution temperature measuring device (1) measures the fire detection optical cable (22), the temperature up to the extended precision measurement optical cable (41) is measured, and the measurement result is acquired from the operating computer (5).

By repeating the measurement N times in this way and averaging the measured results, a precise temperature can be obtained.

The third row of Figure 5 shows the operation of the operating computer (5). At this time, the number of repetitions N can be adjusted by the operating computer according to the desired temperature precision.

Figure 5 is a diagram illustrating the case where the number of N is 4. As the number of N increases, the temperature accuracy increases, but it takes more time to measure the temperature.

When the precision temperature measurement of the precision measurement optical cable (41) is completed N times in this way, the operating computer (5) outputs the temperature measurement result of the precision measurement optical cable (41) and controls the optical switch (3) so that channel 2 of the fire-fighting optical fiber distribution temperature measuring device (1) is connected to another precision measurement optical cable (42) to sequentially measure the temperature of the remaining precision measurement optical cables.

The combination of each block of the block diagram attached to this specification and each step of the flow diagram may be performed by computer program instructions. These computer program instructions may be installed in a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus, so that the instructions, which are executed by the processor of the computer or other programmable data processing apparatus, create a means for performing the functions described in each block of the block diagram or each step of the flow diagram. These computer program instructions may also be stored in a computer-available or computer-readable memory that can be directed to a computer or other programmable data processing apparatus to implement the functions in a specific manner, so that the instructions stored in the computer-available or computer-readable memory can produce an article of manufacture that includes an instruction means for performing the functions described in each block of the block diagram or each step of the flow diagram. Since the computer program instructions can also be installed on a computer or other programmable data processing apparatus, a series of operational steps are performed on the computer or other programmable data processing apparatus to create a computer-executable process, and the instructions that cause the computer or other programmable data processing apparatus to perform the steps for executing the functions described in each block of the block diagram and each step of the flowchart can also provide steps for executing the functions described in each block of the block diagram and each step of the flowchart.

Additionally, each block or step may represent a module, segment, or portion of code that includes one or more executable instructions for performing a specified logical function(s). It should also be noted that in some alternative embodiments, the functions mentioned in the blocks or steps may occur out of order. For example, two blocks or steps depicted in succession may in fact be performed substantially concurrently, or the blocks or steps may sometimes be performed in reverse order, depending on the functionality they serve.

The above description is merely an illustrative description of the technical idea of the present invention, and those skilled in the art will appreciate that various modifications and variations may be made without departing from the essential characteristics of the present invention. Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to explain it, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within a scope equivalent thereto should be interpreted as being included in the scope of the rights of the present invention.

According to the dual-function optical fiber distributed temperature measurement system of the present invention, it is a system designed for cases where temperature measurement for two purposes, namely fire detection and precise temperature measurement, is required at the same time, and it is a solution that can provide a dual-function optical fiber distributed temperature measurement system that can simultaneously implement the functions of fire detection as well as precise temperature measurement by using a fire-fighting optical fiber distributed temperature measurement device that can detect temperature changes around an optical fiber as quickly as possible, and since it overcomes the limitations of existing technologies, it is an invention with industrial applicability because it has sufficient possibility of not only utilizing related technologies but also commercializing or selling the applicable devices, and is clearly implementable in reality.

100: Dual-function fiber optic distribution temperature measurement system
1: Fiber optic distribution temperature measuring device for firefighting 2: Optical cable for fire detection
21: Optical cable for fire detection 1st 22: Optical cable for fire detection 2nd (22)
3: Optical switch 4: Optical cable for precision measurement
5: Operating computer 6: Fire alarm receiver 7: Hub

Claims (10)

In a dual-function optical fiber distributed temperature measurement system that implements the functions of rapid temperature measurement and precise temperature measurement using a fire-fighting optical fiber distributed temperature measurement device,
One or more fire detection optical cables for fire detection;
A fire-fighting optical fiber distributed temperature measuring device that is connected to the above-mentioned fire detection optical cable and measures temperature by averaging Raman scattered light among scattered light generated from the optical fiber;
One or more precision measurement optical cables for precise temperature measurement;
An optical switch that connects the optical cable for fire detection and the optical cable for precision measurement, and selectively switches the optical cable for precision measurement;
A fire receiver that receives the temperature measurement result of the fire detection optical cable from the above fire-fighting optical fiber distribution temperature measuring device and determines whether there is a fire;
In order to obtain the above precise temperature measurement results, an operating computer that averages the temperature measurement results measured over a predetermined period of time through the above precision measurement optical cable and outputs a precise temperature; and
The data output of the above fire-fighting optical fiber distribution temperature measuring device is shared with the fire receiver and the operating computer, and a hub is included that connects the control signal for the optical switch from the operating computer to the optical switch.
When using two optical cables for fire detection, one cable is used as the first optical cable for fire detection, and the other cable is used as the second optical cable for fire detection input to the optical switch.
The above fire-fighting optical fiber distribution temperature measuring device, when using two fire detection optical cables, if the measurement time of the fire-fighting optical fiber distribution temperature measuring device satisfying the conditions defined in the Fire Service Act is T1 per optical cable, the first fire detection optical cable is measured for T1 hours, the second fire detection optical cable is measured for T1 hours, and then the first fire detection optical cable is measured again in this order.
The above operating computer controls the optical switch for each repeated measurement for T1 hour through the second fire detection optical cable. A dual-function optical fiber distributed temperature measurement system characterized in that the temperature information of one precision measurement optical cable connected through the second fire detection optical cable and the optical switch is received through the hub, the temperature measurement results of the one precision measurement optical cable measured for T1 hour are collected a predetermined number of times to obtain a precision temperature measurement result, the temperature is averaged and output as a precision temperature, and the optical switch is controlled again to collect the temperature of another precision measurement optical cable for T1 hour, and the temperature collection and output operation is repeatedly performed for all precision measurement optical cables connected to the optical switch. delete In the first paragraph,
If only one optical cable for fire detection is used,
A dual-function optical fiber distributed temperature measurement system characterized in that the optical cable for fire detection is directly used as an optical cable for precision measurement without the above-mentioned optical switch. In the first paragraph,
If only one optical cable for fire detection is used,
A dual-function optical fiber distributed temperature measurement system characterized by using an optical switch having multiple channels, more than two channels. In the first paragraph,
The above fire-fighting optical fiber distribution temperature measuring device is,
The minimum measurement time t for outputting the temperature,
A dual-function optical fiber distributed temperature measurement system characterized by a fire detection time T1 stipulated by the Fire Service Act and expressed by the relationship T1=nt (n is an integer). In paragraph 5,
The above fire-fighting optical fiber distribution temperature measuring device is,
A dual-function optical fiber distributed temperature measurement system characterized by the relationship T2=N*T1 (N is an integer), where the measurement time in cases where precise temperature measurement is required is T2. delete delete delete In the first paragraph,
The above fire alarm receiver,
A dual-function optical fiber distributed temperature measurement system characterized in that it receives only the temperature measurement result of the first fire detection optical cable from the above fire-fighting optical fiber distributed temperature measurement device to determine whether there is a fire, and outputs an alarm if the measurement result determines that a fire has occurred.