KR20080015639A - A optic fiber temperature monitoring apparatus using for monitoring an electric power equipment - Google Patents

Abstract

An optical temperature monitoring apparatus used for monitoring electric power equipment is provided to measure the temperature of electric power equipment from a distance by connecting a temperature sensor with a processing unit through an optical fiber. An optical temperature monitoring apparatus used for monitoring electric power equipment comprises a light source(1), a beam splitter(2), a lens(3), a temperature sensor(4), an optical fiber(4a), and an optical detector(5). The beam splitter passes a beam under a predetermined wave length and reflects a beam over a predetermined wave length among beams emitted from the light source. The lens focuses the beam passed through the beam splitter. The temperature sensor is attached to the electric power equipment, radiates a beam of a predetermined wave length when the beam is irradiated, and radiates the beam attenuating exponential functionally according to the surrounding temperature when stopping irradiation of the beam. The optical fiber is installed between the temperature sensor and the lens, extends from the temperature sensor as much as a predetermined length to be free from the influence of electro-magnetic force output by the electric power equipment, and transmits the beam irradiated to the temperature sensor and the beam radiated by the temperature sensor. The optical detector converts an optical signal into an electric signal according to the beam irradiated by the temperature sensor, passed through the optical fiber, focused through the lens, reflected through the beam splitter to be projected.

Description

Optical temperature measuring device for monitoring power equipment status {A OPTIC FIBER TEMPERATURE MONITORING APPARATUS USING FOR MONITORING AN ELECTRIC POWER EQUIPMENT}

1 is a perspective view showing an example of a temperature measuring device for monitoring the state of a power device according to the prior art,

Figure 1 (a) is a perspective view showing a resistance thermometer,

1 (b) is a perspective view of an infrared thermal imaging camera,

FIG. 2 is a block diagram illustrating a configuration of an optical temperature measuring device for monitoring a state of a power device according to an embodiment of the present disclosure.

Figure 2 (a) is a block diagram showing the configuration of an optical temperature measuring device for monitoring the state of the power device according to an embodiment of the present invention,

FIG. 2 (b) is a block diagram illustrating a configuration of an electrical signal processor connected to a rear end of a photo detector in an optical temperature measuring device for monitoring a state of a power device according to an embodiment of the present disclosure.

3 is a waveform diagram showing a signal waveform for each step in the optical temperature measuring device for monitoring the power device state according to an embodiment of the present invention.

3 (a) is a waveform diagram of an input signal for controlling the light emission and interruption of the light source,

FIG. 3B is a photodetector output waveform diagram showing an output waveform detected and output by the photodetector according to the control input signal of FIG.

3 (c) is a photo detector output waveform diagram showing only the exponential decay portion of the waveform of FIG. 3 (b) separately;

Fig. 3 (d) is a waveform diagram showing a straight line represented by data when natural logarithm is taken to the value according to the output waveform of Fig. 3 (c).

** Description of the symbols for the main parts of the drawings **

1: light source 2: spectrometer

3: lens 4: temperature sensor

5: optical detector 6: amplification circuit

7: analog-to-digital converter 8: processor

The present invention relates to an optical temperature measuring device for monitoring the status of a power device for monitoring abnormal temperature rise of a power device or a power equipment. Especially, the actual temperature of the power device is always maintained by attaching directly to the heating unit of the power device without additional insulation. The present invention relates to an optical temperature measuring device for monitoring the state of power equipment that can be measured.

In recent years, as the consumption of electric energy increases, electric power facilities are becoming very high voltage and high capacity, and if the electric power facilities, which have a great influence on society as a whole, malfunction due to various causes, they may cause great social disruption and economic loss. Therefore, it is very important to ensure safety and efficiency in the operation of power facilities. In particular, the operation above the limit temperature in the power plant is one of the main causes of the malfunction of the power plant and deteriorates due to various causes, but irrespective of the cause, in most cases it is abnormal in the final accident stage Thermal phenomena such as rising temperatures or fires are present. Therefore, it is necessary to constantly monitor the temperature of power equipment so that the power equipment is always operated at the proper temperature and an alarm occurs early to prevent the safety accident of the power equipment and minimize the spread of damage in the event of an accident.

Meanwhile, an example of a temperature measuring apparatus according to the prior art will be described with reference to FIG. 1.

Figure 1 is a perspective view showing an example of a temperature measuring device for monitoring the state of the power device according to the prior art, Figure 1 (a) is a perspective view showing a resistance thermometer, Figure 1 (b) is a perspective view of an infrared thermal camera It is also.

In FIG. 1A, the RTD is a device in which a resistance value changes depending on an ambient temperature called a resistance temperature detector (RTD), and provides a change in resistance value according to temperature, for example, by a manufacturer of a sensor. The temperature can be measured by a table of temperature versus resistance values.

FIG. 1 (b) is a perspective view of an infrared thermal imaging camera (IR). When an infrared thermal imaging camera (IR) aims a lens at an object whose temperature is to be measured, the object is colored in different colors according to the surface temperature of the object. Can provide a thermal image.

However, the RTD has the advantage of being able to measure the internal temperature of the temperature measurement object of the power device and having an inexpensive price, while measuring the temperature of the power device because the sensor itself is composed of an electrical conductor. There is a risk of causing electrical insulation problems, and there is a problem that is vulnerable to noise due to electromagnetic fields generated around the power equipment.

In addition, the infrared thermal imaging camera (IR) has an advantage of easily knowing the surface temperature of the object to be measured, whereas the internal temperature of the object cannot be measured and the casing is outside of the object. That is, when the object is embedded in the case (case) there is a disadvantage that the temperature measurement is impossible and it is difficult to establish a constant monitoring system.

Therefore, the present invention was devised in view of the above problems, and an object of the present invention is to use an optical temperature measurement method, so that electrical insulation is unnecessary, and the measurement can be performed by spaced apart from the surrounding electromagnetic field by an unaffected distance. The present invention provides an optical temperature measuring device for monitoring the state of power equipment, which can measure temperature and which makes it easy to configure a monitoring device.

An object of the present invention as described above, in the optical temperature measuring device for monitoring the state of power equipment,

A light source;

A spectroscope for selectively transmitting the light emitted from the light source, transmitting a light below a predetermined wavelength and reflecting light having a wavelength larger than the predetermined wavelength;

A lens for condensing and providing light transmitted through the spectrometer;

A temperature sensor attached to a heat generating unit of the power device for monitoring the condition and emitting light having a predetermined wavelength as the light is irradiated, and emitting an exponentially attenuated light according to the ambient temperature when the light is stopped;

It is installed between the temperature sensor and the lens, and extends from the temperature sensor by a predetermined length to prevent the influence of electromagnetic noise from the power device, the light irradiated from the temperature sensor and the light emitted from the temperature sensor Optical fiber to transmit;

And a photo detector which converts an optical signal into an electrical signal according to the light incident through the optical fiber, collected through the lens, reflected through the spectrometer, and incident from the temperature sensor. It can be achieved by providing an optical temperature measuring device for monitoring the state of the power equipment according to the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First, referring to the accompanying FIG. 2, a configuration of an optical temperature measuring device for monitoring power state according to an embodiment of the present invention will be described.

FIG. 2 is a block diagram illustrating a configuration of an optical temperature measuring device for monitoring a state of a power device according to an embodiment of the present disclosure.

Figure 2 (a) is a block diagram showing the configuration of an optical temperature measuring device for monitoring the state of the power device according to an embodiment of the present invention,

FIG. 2 (b) is a block diagram illustrating a configuration of an electrical signal processor connected to a rear end of a photodetector in an optical temperature measuring apparatus for monitoring a power device state according to an embodiment of the present disclosure.

In FIG. 2 (a), the optical temperature measuring device for monitoring the power device state according to an embodiment of the present invention includes: a light source 1; A spectroscope (2) for selectively transmitting the light emitted from the light source (1), for transmitting light below a predetermined wavelength and reflecting light having a wavelength larger than the predetermined wavelength; A lens (3) for condensing and providing light transmitted through the spectroscope (2); The temperature sensor (4) attached to the heat generating unit of the power device for monitoring the condition, emits light of a predetermined wavelength as the light is irradiated, and emits light which exponentially attenuates according to the ambient temperature when the light is stopped. )Wow; It is provided between the temperature sensor 4 and the lens 3, and extends from the temperature sensor 4 by a predetermined length to prevent the influence of electromagnetic noise from the power device, and to the temperature sensor 4 An optical fiber (4a) for transmitting the irradiated light and the light emitted from the temperature sensor (4); The optical signal is converted into an electrical signal according to the light incident through the optical fiber 4a and collected through the lens 3 and reflected through the spectrometer 2 and is incident. It can be configured to include; and a photo detector (5).

Preferably, the light source 1 may be configured as an LED (Light Emitting Device). The light source 1 is not limited to an LED but may be configured as, for example, a laser diode.

Preferably, the spectrometer 2 has a dichroism having the property of transmitting light having a wavelength smaller than a predetermined wavelength, especially light from an LED, and reflecting light having a wavelength larger than the predetermined wavelength, in particular, emitted light from the temperature sensor 4. It is composed of a dichroic beam splitter, and thus, it is possible to prevent incorporation of noisy light that may be intervened.

Preferably, the lens 3 consists of a ball lens. The ball lens is used for matching the central axis of the light emitted from the light source 1 with the central axis of the optical fiber 4a, which is a transmission path of the light, that is, for condensing, in particular connected to the end or the end of the optical fiber 4a. It is easy to mount and fix by an arc welding etc. to a coupler or a light receiving port, and can be comprised preferably. The lens 3 is not necessarily configured as a ball lens, and a general convex lens may also be used, but a ball lens in terms of optical center axis alignment with the optical fiber 4a and convenience of mounting and maintenance of the mounting position. It is desirable to.

 The temperature sensor 4 may be composed of any one of rare earth metal elements. Here, the rare earth metal element means lanthanide 15 elements, scandium (element symbol Sc), and yttrium (element symbol Y). The lanthanide 15 elements are elements of atomic number 57 to 71, and are lanthanum (element symbol La), cerium (element symbol Ce), praseodymium (element symbol Pr), neodymium (element symbol Nd). ), Promethium (element symbol Pm), samarium (Samarium, element symbol Sm), Europium (element symbol Eu), gadolinium (Gadolinium, element symbol Gd), terbium (element symbol Tb), dysprosium (Dysprosium) , Element symbol Dy, Holmium, Element symbol Ho, Erbium, Element symbol Er, Thulium, Element symbol Tm, Ytterbium, Element symbol Yb, Ruthetium, Lu to be.

Rare earth metals have the property of emitting light of a different wavelength, such as 750 nm (nanometer), when irradiated with light of a specific wavelength, such as 630 nm (nanometer). In addition, when the irradiation of the light irradiated on the rare earth metal is stopped, the light emitted from the rare earth metal is attenuated by exhibiting an exponential decay curve, and when the ambient temperature of the rare earth metal is high, the decay rate of the exponential decay curve is increased, In other words, it quickly decays, and taking the natural logarithm to the exponential function increases the slope of the graph.

When the ambient temperature of the rare earth metal is low, the decay rate of the exponential decay curve becomes small, that is, it decays slowly, and when the natural log is taken into the exponential function, the graph of the value decreases as well. Therefore, the temperature of the heat generating portion of the power device can be measured by using the change of the slope indicated by the rare earth metal in accordance with the ambient temperature.

In view of the above characteristics according to the ambient temperature of the rare earth metal, the present invention is configured to measure the temperature by attaching the rare earth metal as a temperature sensor to a heat generating part of a power device or a power equipment (for example, an ultra-high pressure gas insulated switch).

Since the optical fiber 4a itself has a very low optical loss ratio compared to its length, the optical fiber 4a is sufficiently spaced apart from the heat generating portion of the power device, which is the temperature measurement object, so that the It may be determined and configured to have a predetermined long length so as to exclude the influence.

The photo detector 5 converts and provides an optical signal reflected through the spectroscope 2 into an electrical signal, and may be selectively configured, for example, by a well-known photoconductor photodetector, a semiconductor diode photodetector, or the like.

On the other hand, in the optical temperature measuring device for monitoring the power device state according to an embodiment of the present invention configured as described above, is connected to the rear end of the photo detector 5, according to the temperature provided by the photo detector 5 Referring to FIG. 2 (b), a configuration for finally obtaining a heat generating unit temperature of a power device to be measured by processing an electrical signal is as follows.

FIG. 2 (b) is a block diagram illustrating a configuration of an electrical signal processor connected to a rear end of a photodetector in an optical temperature measuring apparatus for monitoring a power device state according to an embodiment of the present disclosure.

The electrical signal processor is connected to the output of the photodetector 5, the amplifying circuit (6) for amplifying and providing a voltage of the electrical signal according to the emission light from the temperature sensor (4) output by the photodetector (5) Wow;

An analog-to-digital converter (7) for converting an electrical signal amplified by the voltage provided by the amplification circuit (6) into a digital signal and outputting the digital signal;

On the basis of the digital signal output from the analog-to-digital converter 7, a natural log is taken on the value of the digital signal according to the light which is exponentially attenuated according to the ambient temperature when the irradiation of the light is stopped. And a processor 8 for calculating a slope of the value and determining the temperature of the power device by comparing the calculated slope with a slope reference value according to a pre-stored temperature.

The processor 8 may be composed of arithmetic means capable of arithmetic processing according to a program stored in advance for digital values such as a microprocessor or a personal computer.

According to the present invention, as a configuration for controlling the lighting and turning off of the light source 1, for example, an input / output circuit (not shown) for providing a control signal from the processor 8 to the light source 1 may be configured. In addition, there may be a modified embodiment of separately configuring a square wave oscillation circuit (not shown) for providing the square wave input signal 4-1 as shown in FIG. 3 to control the lighting and turning off of the light source 1.

The operation of the optical temperature measuring device for monitoring the state of power equipment according to an embodiment of the present invention configured as described above will be described with reference to FIGS. 2 to 3.

When the square wave input signal 4-1 is provided to the light source 1 from the input / output circuit (not shown) or the square wave oscillation circuit (not shown) at all times, the light source 1 receives the square wave input signal 4-1. Light is emitted for a high level time and light emission is stopped for a time when the square wave input signal 4-1 is low level.

Light emitted from the light source 1 passes through the spectrometer 2 and is collected through the lens 3 and irradiated to the temperature sensor 5 through the optical fiber 4a.

Since the temperature sensor 5 is made of a rare earth metal material as described above, the square wave input signal 4-1 in which the irradiation of light is stopped in accordance with the ambient temperature of the position where the temperature sensor 5 is installed, that is, the internal temperature of the heat generating portion of the power device, is applied. Emits exponentially decaying light for a time at which is low level.

Therefore, the exponentially attenuated light emitted from the temperature sensor 5 is transmitted again through the optical fiber 4a, collected through the lens 3, reflected by the spectroscope 2 and reflected by the photodetector 5. Is detected.

The photodetector 5 converts the optical signal emitted from the detected temperature sensor 5 and reflected by the spectrometer 2 into an electrical signal and outputs the signal waveform as shown in FIG.

The signal waveform shown in FIG. 3 (b) output by the photodetector 5 is a temperature-independent period 4-2 corresponding to the time when the square wave input signal 4-1 is at a high level. And a temperature characteristic related section 4-3 which attenuates exponentially in response to the time when the square wave input signal 4-1 is at a low level.

 When the photodetector 5 outputs an electrical signal such as a signal waveform as shown in Fig. 3B, it is processed by the signal processing means according to the present invention as shown in Fig. 2B.

That is, the amplifier circuit 6 amplifies and outputs the voltage of the electrical signal output from the photodetector 5, and the analog-to-digital converter 7 digitally converts the electrical signal amplified by the voltage provided by the amplifier circuit 6. Convert it to a signal and output it.

Thus, the electrical signal converted into a digital signal is transmitted to the processor 8 for processing. That is, the processor 8 takes a natural logarithm on the digital value of the waveform as shown in FIG. Obtain the data value of the waveform as 3 (d). The data value is shown along a waveform as shown in FIG. 3 (d) of a linear waveform with a constant slope, and the slope of the linear waveform varies with the ambient temperature of the temperature sensor 4. That is, when the ambient temperature of the temperature sensor 4 is high, the slope of the linear waveform of the data value is large (the steep slope), and when the ambient temperature of the temperature sensor 4 is low, the slope of the linear waveform of the data value is small. (The slope is gentle).

Therefore, the processor 8 converts the measured slope using the reference data of the pre-stored inclination and the reference data of the pre-stored inclination into the temperature value for the pre-stored inclination to complete the temperature measurement.

It is foreseeable that a means for alerting the administrator may additionally be included if the temperature of the power device measured according to the invention exceeds, for example, the normal level of the preset power device. Such alarm means may include various embodiments, such as a buzzer, a constantly flashing alarm lamp, a voice alarm by a stored voice or an acoustic message.

As described in detail above, by providing a light temperature measuring device for monitoring the state of the power device according to the present invention, the present invention uses an optical temperature measurement configuration and method, that is, the temperature sensor itself is different from the irradiation light according to the ambient temperature Since it is composed of a rare thorium metal material that emits light, it is not necessary to electrically insulate the temperature sensor, and thus it is possible to avoid the cost and time required by installing a separate means necessary for the electric insulation.

In addition, the optical temperature measuring device for monitoring the state of the power device according to the present invention is configured by a sufficient distance between the temperature sensor and the processing unit performing the electrical processing by the optical fiber, so as to be spaced apart from the surrounding electromagnetic field by the power device by no influence. It is possible to measure the temperature.

In addition, it is possible to measure the internal temperature of the object, there is an effect that can obtain an optical temperature measuring device for monitoring the state of the power device, which is easy to configure the constant-time monitoring device.

Claims (6)

In the optical temperature measuring device for monitoring the state of power equipment, A light source; A spectroscope for selectively transmitting the light emitted from the light source, transmitting a light below a predetermined wavelength and reflecting light having a wavelength larger than the predetermined wavelength; A lens for condensing and providing light transmitted through the spectrometer; A temperature sensor attached to a heat generating unit of the power device for monitoring the condition and emitting light having a predetermined wavelength as the light is irradiated, and emitting an exponentially attenuated light according to the ambient temperature when the light is stopped; It is installed between the temperature sensor and the lens, and extends from the temperature sensor by a predetermined length to prevent the influence of electromagnetic noise from the power device, the light irradiated from the temperature sensor and the light emitted from the temperature sensor Optical fiber to transmit; And a photo detector which converts an optical signal into an electrical signal according to the light incident through the optical fiber, collected through the lens, reflected through the spectrometer, and incident from the temperature sensor. Optical temperature measuring device for monitoring the state of power equipment. The method of claim 1, The temperature sensor is an optical temperature measuring device for monitoring the state of the power device, characterized in that consisting of any one of rare earth metal elements. The method of claim 1, An amplifying circuit connected to an output of the photodetector and amplifying and providing a voltage of an electrical signal according to radiated light from a temperature sensor output by the photodetector; An analog-digital converter for converting an electrical signal amplified by the amplification circuit and converting the electrical signal into a digital signal and outputting the digital signal; On the basis of the digital signal output from the analog-to-digital converter, the natural log is taken to the value of the digital signal according to the light which exponentially attenuates according to the ambient temperature when the irradiation of the light is stopped, and the slope of the natural log value And a processor configured to determine the temperature of the power device by comparing the calculated slope with a slope reference value according to a pre-stored temperature; and additionally, the power device state monitoring optical temperature. Measuring device. The method of claim 1, The light source is an optical temperature measuring device for monitoring the power device status, characterized in that consisting of an LED (Light Emitting Device). The method of claim 1, And said lens is comprised of a ball lens. The method of claim 1, And the spectrometer comprises a dichroic beam splitter.

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