JPS5879430A - Device for automatically monitoring internal partial discharge of transformer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to partial discharge (hereinafter referred to as FD) occurring inside a transformer.
Automatic internal partial discharge monitoring equipment for transformers that automatically monitors the occurrence of

With the increase in electricity** in recent years, the transformers used in the power transmission system are also becoming larger in capacity and becoming ultra-southern voltage.

Therefore, if a serious accident occurs in power transmission equipment, the impact on the power transmission system and society will be significant, and accidents must be prevented as much as possible. In recent years, there has been a trend toward preventing accidents from occurring in transformers and other power transmission equipment by catching them in advance.

General C, transformation grade all-road breaking Jll jJ! The predecessor of L2 is FD, which occurs inside a transformer. Therefore, monitoring the occurrence of this FD can be one way to prevent the entire circuit breakdown of the transformer. 3
11 Figure 1: 5IFi is a sealed tank in which insulating oil 10 is placed inside and also contains a transformer body 2, lead wires 3, etc. 2 transformer bodies.

The outer wall of the tank 1 is connected to the airborne bushing 4 through the lead iss.
There are multiple pieces (usually 3 to 6 pieces)! installed in place. The corona microphone 5 has a function of detecting the FD ultrasonic waves generated in the tank 1, transmitting and amplifying the electrical signals. Furthermore, the current pulse associated with FD phenomenon C is detected by the detector 7 from the bushing tap 6 or the neutral point of the transformer. and the detected ultrasound, 11
The flow pulses are transmitted to the monitoring am body 9 by means of a transmission cable 8 . In an internal PDM viewing device with such a configuration, for example, the distinction between FD generated within the transformer and FD occurring outside the transformer (e.g., airborne corona, surge, etc.) is determined by the monitoring device main body 9 described above. It's done inside. The criteria for this judgment are the detection signal from the corona microphone 5,
It depends on whether or not there are both current pulse detection signals from the detector 7 and the current pulse detection signal from the detector 7. However, as is well known, inside the transformer there is a 52 tap switching % JO during load operation.
When manufacturing the tap changer of this on-load tap changer lO,
There is an operating noise and a change in current occurs. Therefore, the corona microphone 5 described above detects the operating sound, and the current pulse detector 7 also detects the current pulse, and the monitoring device 2) This is the cause of the error 1 for internal FD generation C2 of the monitoring device 9.
An example of a dynamic noise generated inside a transformer and current pulses detected is the operating timing of the oil circulation pump 11.The present invention has been made to solve the above problems, and : Attached, mechanically operated on-load tap changer,
#14 due to the operation of the auxiliary equipment of the transformer, such as the oil circulation pump.
An object of the present invention is to provide a partial discharge monitoring device for a transformer that does not generate u.

An embodiment of the present invention will be described below. Load tap changer 10. During the mechanical operation of the oil circulation pump 11, operating noise is generated inside the transformer and current pulses are detected by the detector 67. Therefore, when the auxiliary equipment attached to the transformer main body is mechanically operated, the C1 monitoring device main body 9 is configured to stop monitoring for a certain period of time until the mechanical operation of the auxiliary equipment is completed. In this way, for example, when the on-load tap changer IO is mechanically operated, even if an operating sound is heard inside the tank 1 and a current pulse is detected, the monitoring device main body 9 cannot monitor it during that time. Since it has been released, there is no risk of w4M on the monitoring device itself. In addition, the time required to release the monitoring device main body is, for example, several m8 or less when the oil circulation pump 11 is starting up, and even when the tap changer 10 is operating, it only takes am8. There is no risk that the functionality will be degraded at all.

Next (l:!)1
The signal 1 represents, for example, a control signal for a tap changer.

Among them, 12 is a control signal CH to the monitoring device main body 9.
2, and is generated prior to the tap switching operation signal No. 13 by T1 time.

The old woman's T1 time was 1m8 or less. When the monitoring device main body 9 receives the CHI 12 signal, it ignores all the signals from the transmission line 8, for example, and cancels the monitoring operation. Then, after the operating time of the tap changer 10 ends (
After T2) I;, a signal 14 is generated at CHI21-, and the automatic monitoring function of the main body of the monitoring device is restored. As described above, it is sufficient for this time T2 to be about several m8.

As explained above, according to the QIJ, auxiliary equipment attached to the transformer body, such as on-load tap changers, oil circulation pumps, etc., which are attached to the transformer body and operate as the load increases or decreases in the general I: transformation gain. 1 for monitoring partial discharge within 85 by mechanical operation
It is possible to provide an automatic partial discharge monitoring device for a reliable transformer that does not cause 114M.

[Brief explanation of drawings]

FIG. 1 is a diagram for explaining the outline W* of an internal partial discharge monitoring device for a transformer, and FIG. 2 is a diagram for explaining the operating principle of the internal partial discharge monitoring device for a transformer according to the present invention g2.

Claims (1)

[Claims] 1. Inside a sealed tank filled with insulating medium! = Inside of the transformer that houses the transformer body and automatically detects partial discharge occurring in this sealed tank using at least one of acoustic means and electrical means for detecting current pulses. Partial discharge self-discharge (ALA) 2. From the start of mechanical operation of the transformer main body auxiliary equipment of the on-load tap changer that is attached to the transformer main body and that operates mechanically, and the insulating medium circulation pump. Automatic internal partial discharge monitoring of a transformer, characterized in that the monitoring operation of the main body of the monitoring device to which the acoustic means and the electric means are connected is canceled for a certain period of time to prevent false occurrences of internal partial discharge. 2. The automatic internal partial discharge monitoring device for a transformer according to claim 1, wherein the acoustic means in device 02 is a corona microphone.