JPH07297038A - Internal abnormality detection device and internal abnormality detection method for electric equipment - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide an internal abnormality detection device and an internal abnormality detection method for an electric device, which has a simple structure and enables early confirmation of oil leakage. [Structure] An abnormality detection device is arranged near the bottom of a tank and detects the pressure of insulating oil near the bottom of the tank, and the output signal of this pressure sensor determines whether or not there is an abnormality in the insulating medium in the tank. And a determination device 5 that does.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal abnormality detection device and an internal abnormality detection method for electric equipment, and in particular, a liquid such as mineral oil or perfluorocarbon liquid is sealed inside the electric equipment as a cooling and insulating medium. The present invention relates to a device for detecting liquid leakage and internal abnormality of an electric device and a detection method thereof.

[0002]

2. Description of the Related Art As this type of oil leakage detection device which has been generally adopted, a device shown in FIG. 3 is known. That is, the oil level of the transformer tank 1 filled with insulation 4 oil is detected by the oil level gauge 9 provided in the conservator 2, and the oil temperature detectors 10a provided at a plurality of positions such as the upper and lower portions of the tank, The temperature of the insulating oil 4 is detected by 10b.

Then, the detected oil level detection signal S1 and the oil temperature detection signal S2 are sent to the determination device 5 which is composed of a microcomputer having a calculation function, and the average oil temperature is detected from a plurality of oil temperature detection signals. The temperature was calculated, and this was compared with the oil level signal to determine oil leakage.

Further, as a simple device, an oil leak detecting device as shown in FIG. 4 is also known. That is, the oil level gauge 9 is provided in the conservator 2 and the oil level detection signal S1
Is configured to monitor the oil surface and issue an alarm when the oil surface is abnormally lowered.

[0005]

In the internal abnormality detecting device formed as described above, in the former case of the oil leak determination,
Since it is judged from the oil level and the oil temperature, there is a dislike that the structure of the oil leak detection device is complicated, and the abnormality determination standard is complicated, and when the oil level drops to the minimum level of the oil level meter 9. Since the oil leak alarm is issued in the above, there is a dislike that it is not possible to confirm the oil leak early by spending a predetermined time from the occurrence of the oil leak until the alarm is issued.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an internal abnormality detecting device and an internal abnormality detecting method for an electric device of this kind, which enables early confirmation of oil leakage with a simple structure. is there.

[0007]

That is, the present invention relates to an internal abnormality detection device, which is provided below an insulating oil surface of a tank and which detects a pressure of insulating oil (insulating medium) in the tank. A determination device for determining whether or not there is an abnormality in the insulating medium in the tank based on the output signal of the pressure sensor is provided to achieve the intended purpose.

[0008]

In other words, the internal abnormality detecting device for electric equipment formed in this manner has only a pressure detecting part and a judging part, and the structure is very simple. Since it is a judgment, the abnormality judgment is not complicated, and when an oil leak occurs, the leak can be confirmed early.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the illustrated embodiments. FIG. 1 shows the case of a transformer provided with the internal abnormality detecting device. Reference numeral 1 denotes a transformer tank, in which a device body 3, that is, a transformer core and windings are housed. The tank is filled with insulating oil 4 for cooling the device body 3. A conservator 2 for absorbing expansion and contraction of the insulating oil 4 is provided in an upper portion of the tank 1 that houses the insulating oil 4 together with the device body 3.

On the other hand, near the bottom of the tank 1, the tank 1
Pressure detector (pressure sensor) that detects the pressure of the inner insulating oil 4
7b is attached. The pressure detector 7b is formed so as to detect the pressure rise rate of the insulating oil 4 in addition to the pressure of the insulating oil 4 in the tank 1. Further, this pressure detector is connected to the determination device 5 which is composed of a microcomputer or the like having a calculation function.

Then, the detected pressure detection signal is sent to the determination device 5. The pressure at the time of injecting the insulating oil 4 is stored in the determination device 5 in advance.

In the oil leak detecting device of the present invention thus constructed, the pressure of the insulating oil 4 and the rate of pressure rise are constantly monitored by the pressure detectors 7a and 7b.

If the detected pressure becomes lower than the pressure when the insulating oil 4 is injected, the determination device 5 outputs an oil leak alarm signal 6. When the rate of pressure increase is large, the determination device 5 outputs the alarm signal 6 for internal abnormality.

In the above description, the insulating oil 4 in the tank is
Although it has been described that the pressure detector 7b for detecting the pressure is provided near the bottom of the tank, it does not always have to be provided in this way, and may be provided below the vicinity of the insulating oil surface, for example. Let's do it. However, in this case, it is necessary to consider the volume change of the insulating oil due to the temperature change.

In FIG. 2, instead of the conservator 2 of FIG. 1, an inert gas 8 is filled in the upper part of the tank 1, and the expansion and contraction of the insulating oil 4 is absorbed by the inert gas 8. 1 shows an example in which the present invention is applied to a device.

A pressure detector 7a for detecting the pressure of the inert gas 8 is provided in the upper part of the tank 1, and an insulating oil 4 is provided in the lower part of the tank 1.
A pressure detecting device 7b for detecting the pressure is attached. The pressure detector 7b is formed so as to detect not only the pressure of the insulating oil 4 in the tank 1 but also the pressure difference between the inert gas 8 and the insulating oil 4 and the pressure increase rate. Further, this pressure detector is connected to the determination device 5 which is composed of a microcomputer or the like having a calculation function.

That is, in the case of an electric device in which an inert gas is filled in the upper part of the insulating oil 4, the gas chamber capacity changes due to the temperature change of the insulating oil 4, the gas pressure changes, and the gas pressure is superimposed on the lower pressure. Therefore, the gas pressure is detected and the differential pressure from the lower pressure is monitored.

With such a configuration, the detected pressure detection signals are sent to the determination device 5, respectively. The pressure difference between the inert gas 8 and the insulating oil 4 when the insulating oil 4 and the inert gas 8 are injected is stored in the determination device 5 in advance.

The detected pressure difference is the insulating oil 4 and the inert gas 8
If it becomes lower than the pressure difference at the time of injection, the determination device 5 outputs an oil leak alarm signal 6a. When the rate of pressure increase is large, the determination device 5 outputs the alarm signal 6b for internal abnormality.

In the case of an electric device using a perfluorocarbon liquid that is colorless and transparent instead of the insulating oil 4 and easily evaporates into the atmosphere, it is very difficult to visually detect the liquid leakage. Is particularly effective when used in such electrical equipment.

[0021]

As described above, according to the present invention, the internal abnormality detecting device is provided with a pressure sensor arranged near the bottom of the tank for detecting the pressure of the insulating oil near the bottom of the tank, and an output signal of the pressure sensor. A judgment device for judging the presence or absence of an abnormality in the insulating medium in the tank was provided to detect an internal abnormality, so the configuration of the device is very simple, and the judgment is made by comparing the pressure. The determination is not complicated, and when an oil leak occurs, it can be confirmed early.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional side view showing an embodiment of an internal abnormality detection device for an electric device according to the present invention.

FIG. 2 is a vertical cross-sectional side view showing another embodiment of the internal abnormality detecting device for electric equipment of the present invention.

FIG. 3 is a vertical cross-sectional side view showing a conventional internal abnormality detection device for an electric device.

FIG. 4 is a vertical sectional side view showing a conventional internal abnormality detection device for an electric device.

[Explanation of symbols]

1 ... Tank, 2 ... Conservator, 3 ... Machine body, 4 ... Insulating oil or perfluorocarbon liquid, 5 ... Judgment device, 6 ...
Alarm signal, 7a, 7b ... Pressure detector, 8 ... Inert gas,
9 ... Oil level gauge, 10a, 10b ... Oil temperature detector.

Claims (10)

[Claims] 1. An internal abnormality detection method for detecting an internal abnormality of an electric device in which an insulating medium is filled in a tank together with an electric device body, wherein an abnormality inside the electric device is detected from a pressure change of the insulating medium in the tank. A method for detecting an internal abnormality of an electric device, characterized in that 2. An internal abnormality detecting method for detecting an internal abnormality of an electric device in which an insulating medium is filled in a tank together with an electric device body, wherein an abnormality inside the electric device is detected by a pressure change of the insulating medium near the bottom of the tank. A method for detecting an internal abnormality of an electric device, which is characterized in that: 3. A method of detecting an internal abnormality of an electric device, wherein the tank is filled with an insulating medium together with an electric device body, wherein a change in pressure and a rate of increase in pressure of the insulating medium near the bottom of the tank are detected. A method for detecting an internal abnormality of an electric device, which further comprises determining an abnormality inside the electric device. 4. An internal abnormality detection method for detecting an internal abnormality of an electric device in which a tank is filled with an insulating medium together with an electric device body, wherein the pressure and the rate of pressure rise of the insulating medium near the bottom of the tank are measured. A method for detecting an internal abnormality of an electric device, wherein the measured value is compared with a pressure and a pressure increase rate of an insulating medium in a normal operation state to judge an abnormality inside the electric device. 5. An internal abnormality detection device for an electric device, wherein the tank is filled with an insulating medium together with the main body of the electric device, wherein the tank is arranged below the insulating medium surface of the tank and detects the pressure of the insulating medium in the tank. An internal abnormality detection device for an electric device, comprising: a pressure sensor; and a determination device that determines whether or not there is an abnormality in the insulating medium based on an output signal of the pressure sensor. 6. An internal abnormality detection device for an electric device in which a tank and an electric device body are filled with an insulating medium, the pressure sensor being arranged near the bottom of the tank and detecting the pressure of the insulating medium near the bottom of the tank. And an internal abnormality detection device for electric equipment, comprising: a determination device that determines whether or not there is an abnormality in the insulating medium based on an output signal of the pressure sensor. 7. An internal abnormality detection device for an electric device in which a tank is filled with an insulating medium together with an electric device main body, wherein the pressure and the rate of pressure rise of the insulating medium near the bottom of the tank are arranged near the bottom of the tank. An internal abnormality detection device for an electric device, comprising: a pressure sensor for detecting; and a determination device for determining whether or not there is an abnormality in the insulating medium based on an output signal of the pressure sensor. 8. An internal abnormality detection device for an electric device, wherein the tank is filled with an insulating medium together with the main body of the electric device, wherein the tank is arranged near the bottom of the tank, and the pressure and the rate of pressure rise of the insulating medium near the bottom of the tank are measured. A pressure sensor for detecting and a determination device for determining whether or not there is an abnormality in the insulating medium by comparing an output signal of the pressure sensor with a prestored output signal of the pressure sensor during normal operation. An internal abnormality detection device for electric equipment, characterized in that 9. A tank of an electric device, wherein the tank is filled with an electric device body together with an insulating liquid and an inert gas, and expansion and contraction of the insulating liquid due to a temperature change are absorbed by the volume change of the inert gas. In an internal abnormality detection device for detecting an internal abnormality, a pressure sensor that is arranged near the bottom of the tank, detects the pressure of the insulating medium near the bottom of the tank, and is arranged in the upper part inside the tank, and the pressure of the inert gas. An internal abnormality detection device for an electric device, comprising: a pressure sensor that detects a pressure difference; and a determination device that determines whether or not there is an abnormality in the insulating medium based on a pressure difference between output signals of these pressure sensors. 10. An electric device which is filled with an insulating liquid and an inert gas in a tank together with an electric device main body and absorbs expansion and contraction of the insulating liquid due to temperature change by volume change of the inert gas. In an internal abnormality detection device for detecting an internal abnormality, a pressure sensor that is arranged near the bottom of the tank, detects the pressure of the insulating liquid near the bottom of the tank, and is arranged above the inside of the tank, and the pressure of the inert gas. An internal abnormality detection device for an electric device, comprising: a pressure sensor for detecting the presence of a pressure sensor; .