JP2520866B2 - Transformer operation monitoring device - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a transformer operation monitoring device, and more specifically, by constantly monitoring the tap switching time of a transformer load tap switching device, The present invention relates to a transformer operation monitoring device that performs early abnormality detection of a tap switching device when a transformer is loaded.

[Conventional technology]

In the case of changing the voltage tap ratio of a transformer, the tap switching device during load of the transformer (hereinafter referred to as “tap engineer”) is short-circuited between the taps to be switched of the tap winding in the transformer through a temporary resistor or a reactor. If the switching mechanism does not operate normally, an excessive short-circuit current will occur between the taps of the tap winding, resulting in a serious accident. In order to prevent this accident and operate the transformer normally, the number of times the tap engineer has been operated has been conventionally monitored, and when the specified number of times is reached, parts are replaced and the time including the switching operation preparation time during tapping engine operation is also included. Although monitoring is performed, it is difficult to grasp the precursor phenomenon of the abnormality because it is not monitoring the actual tap switching time as short as several tens of milliseconds, and it cannot be said to be sufficient as an abnormality prediction method. On the other hand, at the time of inspection inspection by a person, an abnormality may be found from the tap switching sound due to the difference from the normal state, but in order to detect this abnormality by hearing, it is necessary for the person to go near the transformer. Sometimes the taps are switched, and only when there are various conditions such as the patrol crew can judge whether the tap tap engineer is normal or abnormal based on the switching sound of the tap tape engineer. It is not sufficient as an abnormality detection method because it is required and not always monitored.

[Outline of Invention]

This invention eliminates the above-mentioned drawbacks of the conventional tapping-engine monitoring method, performs constant monitoring, and detects vibrations and sound levels at a substantial tap-switching time of several tens of milliseconds to perform judgment processing. The present invention provides a transformer operation monitoring device capable of automatically detecting an abnormality in a tap engine in the device.

Example of Invention

FIG. 1 shows a first embodiment of the present invention, in which a tap switching drive device 2 disposed above a tank 1 of a tape engine, a tank switching switch 3 housed in the tank 1, and a tap selector 4 are provided. Are combined. Tank 1
The vibration detector 5 is mounted on the side wall of the device, and the output of the vibration detector 5 is input to the determination device 6. The judging device 6 comprises a signal converter 7 to which the output of the vibration detector 5 is applied, a filter circuit 8 and a judgment processing circuit 9, and the tap switching trajectory signal 10 is inputted to the judgment processing circuit 9.

 Next, the operation will be described.

At the time of tap switching, the contact inside the switching switch 3 is switched by releasing the mechanical energy stored in the spring in the tap switching drive device. A pressure rise occurs due to the generated arc, and the wall of the tank 1 is vibrated through the insulating oil in the tank 1. This vibration is detected by a vibration detector 5 attached to the tank wall, converted into an electric level signal by a signal converter 7, and guided to a judgment processing circuit 9 through a filter circuit 8 for removing noise. The decision processing circuit 9 takes in only the vibration signal for a certain period of time after receiving the tap switching start signal 10 as correct information in order to remove an error due to a disturbance other than tap switching. If mechanical malfunctions or the like in the tap drive 2 or switching switch 3 begin to occur, the tap switching time becomes long and the arc energy at the time of switching increases, so that the pressure in the tank 1 rises. As a result, the vibration level also increases. Therefore, when the driving vibration level is higher than the preset vibration level, the judgment processing circuit 9 judges that the tap engine is abnormal and outputs an alarm.

FIG. 2 shows a second embodiment, which is compared with the preset vibration level in the embodiment of FIG. 1, but by providing the data storage arithmetic processing circuit 11 in the judging device 6, this data storage arithmetic The measurement data is stored in the processing circuit 11, the frequency distribution as shown in FIG. 3 is obtained, and the standard deviation value δ is further obtained. When the measurement data is larger than the average value by several times δ (for example, 3δ) or more, it is abnormal. By adding a statistical processing function such as determining that the abnormality can be predicted with higher accuracy.

FIG. 4 shows a third embodiment, in place of the vibration detector,
The acoustic detector 5a is arranged near the outside of the tank 1. Other parts are the same as in FIG.

In this embodiment, since the vibration of the wall of the tank 1 which occurs at the time of tap switching propagates to the outside as a sound, this sound is detected by the sound detector 5a and this detection signal is input to the determination device 6. The same effect as in the first embodiment can be obtained.

The vibration detector 5 of the second embodiment shown in FIG.
, May be replaced with an acoustic detector arranged near the tank,
It is easy to see that the same effect can be obtained.

〔The invention's effect〕

As described above, the present invention detects the increase in the level of vibration or sound associated with the increase in the internal pressure, which is a precursor of the abnormality in the tappet engineer at the time of tap switching, and detects the abnormality of the tappet engineer. Compared with the monitoring method described above, there is an effect that the abnormality can be detected early automatically and accurately.

[Brief description of drawings]

FIG. 1 is a connection diagram of the first embodiment of the present invention, FIG. 2 is a connection diagram of the second embodiment, and FIG. 3 is a vibration level-number of operation histogram diagram of the second embodiment. The drawing is a connection diagram of a third embodiment of the present invention. 1 ... Tap for load tap switching device, 2 ... Tap switching drive device, 3 ... Tap switching switch, 4 ... Tap selector, 5 ... Vibration detector, 5a ... Sound detector, 6
...... Judgment device, 7 ...... Signal converter, 8 ...... Filter circuit, 9 ...... Judgment processing circuit, 10 ...... Tap switching start signal, 11 ...... Data storage arithmetic processing circuit. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (4)

(57) [Claims] 1. A vibration or acoustic detector disposed in a load tap switching device of a transformer, a signal converter for converting a signal from the detector into a predetermined electric signal, and the signal converter. Of a transformer comprising a determination processing circuit for receiving an output of a power supply device and a tap change signal during load, and determining whether or not there is an abnormality in the load tap changeover device based on a vibration / sound level obtained in synchronization with the signal. Monitoring equipment. 2. Data for memorizing vibration / sound levels at the time of tap switching, performing statistical processing, and judging whether or not there is an abnormality in the tap switching device under load from the level based on an allowable value from the statistical processing. The transformer operation monitoring device according to claim 1, further comprising a storage arithmetic processing circuit. 3. The transformer operation monitoring device according to claim 1 or 2, further comprising a vibration detector mounted on a tank wall of the load tap changer. 4. The transformer operation monitoring device according to claim 1 or 2, further comprising an acoustic detector disposed near the tank of the load tap changer.