JPS5944585B2 - Device for measuring opening/closing speed of circuit breakers - Google Patents

Description

[Detailed description of the invention] The present invention relates to a device for measuring the opening and closing speed of fences and disconnectors.

As is well known, when manufacturing Nishiya disconnectors, it is required by standards to conduct an opening/closing speed test.

Conventionally, a potentiometer has been used to measure this speed. That is, a slider of a potentiometer is connected to a movable part such as a movable contactor or a movable electrode of a disconnector to be measured, and the resistance change is read as a voltage, which is used as an input to an electromagnetic oscilloscope. However, when using this device, not only is it difficult to connect the movable part and the slider, but the desired measurement accuracy cannot be obtained unless the two are properly centered, and this adjustment work is difficult. It was hot.

Furthermore, since the movable parts of disconnectors move at a high speed of, for example, several m/s, the slider in the potentiometer is likely to cause poor contact, making it difficult to obtain an accurate opening/closing speed curve. In addition, there was a problem in that it was difficult to accurately measure the speed of the breakers because they vibrated when they were opened and closed. The present invention aims to provide a device for measuring the opening/closing speed of breakers, which overcomes the above-mentioned drawbacks by using an eddy current horizontal non-contact displacement meter.

The present invention will be explained below based on the drawings. FIG. 1 is a block diagram showing one embodiment of the present invention, in which numeral 1 indicates an object to be measured and the figure exemplifies a vacuum sensor. 2 and 3 are fixed and movable electrodes, 4 and 5 are fixed and movable electrode rods led out of the outer box, and 6 is a conductor connected to the movable electrode rod 5.

Reference numeral 7 designates a well-known eddy current horizontal non-contact displacement meter, which includes a pickup coil 8, a high frequency oscillator 9, a coupling resistor 10, a tuning amplifier 11, a wave detector 12, a power amplifier 13, and the like.

Reference numeral 14 denotes an electromagnetic oscilloscope to which the output of the displacement meter T is given and displays this on a time axis.

Then, the high frequency signal from the oscillator 9 is applied to the coil 8. An example of how the conductor 6 is located within the range of this magnetic field is by arranging the coil 8 facing the conductor 6 with a gap length d and using the frame of a device to be measured or a disconnector (not shown). Secure the disconnection device to parts other than the movable parts using a fixing device.

Next, the operation will be explained.

In the configuration described above, a high frequency wave having a frequency FO is supplied from the oscillator 9 to the coil 8 and the tuning circuit 11.
0, and its resonance curve is given in FIG. 2A. Here, if a shear disconnection command is given to the shear breaker 1 and the electrode 3 is separated from the electrode 2, the conductor 6 disposed within the magnetic field of the coil 8 will also operate accordingly. Reduce the gap length d. That is, the conductor 6 is the movable contact 3
indicates the same stroke. Therefore, a change in the magnetic field occurs within the conductor 6, and the eddy current generated therein reduces the inductance of the coil 8 and increases the effective resistance. Therefore, as shown in FIG. 2B, the resonance frequency f1 changes in the direction of increasing, and the coupling coefficient with respect to the frequency FO becomes like EOl in FIG. 2. The output of the coil 8 obtained as a function of the gap length d is amplified by a tuning amplifier 11 and then detected by a detector 12 to obtain a DC output corresponding to the gap length d.

This output is amplified by a power amplifier 13 and then fed to an electromagnetic oscilloscope 14 to be displayed on the time axis. Therefore, the opening speed curve of the breaker 1 is drawn in the onlogram obtained here. When the shield breaker 1 is closed, the gap length d increases and the opposite phenomenon to that described above appears in each part. FIG. 3 shows the opening speed curve of a vacuum shield breaker, where X shows the case where the present invention is applied and y shows the case where the conventional potentiometer method is used. As is clear from the figure, in the case of the present invention, there is no discontinuity in the curve due to poor contact, etc., unlike in the case of the conventional device. In addition, since the coil 8 is fixed to a part other than the movable part of the cutter or disconnector to be measured, even if the cutter or disconnector to be measured vibrates during opening/closing operations, this is canceled out and the opening/closing degree can be measured accurately. .

FIG. 4 exemplifies the case where the vacuum shield breaker 1 is mounted in the outer box 15 and an opening/closing speed test is performed on it immediately before shipping.

That is, after removing the external terminal 17 of the insulator tube 16 of any phase by loosening the screw 18, the other end of the auxiliary rod 20 to which the conductor 6 is fixed at one end is inserted through a small hole previously provided in the insulator tube end fitting 19. is inserted into the screw hole provided in the movable rod 5 of the shear cutter 1 and fixed. Moreover, the coil stand 21 is screwed and fixed into the mounting screw hole of the external terminal 17, and the pick-up coil 8 is attached to this and fixed with a predetermined gap length d between it and the conductor 6. As a result, the conductor 6 is placed within the magnetic field of the coil 8. If the shield breaker 1 is operated here, the conductor 6 comes close to or separated from the coil 8, and the opening/closing speed test can be easily performed. The coil 8 is attached to the outer box 15 side of the disconnector 1, such as a metal fitting 19, on the coil stand 21, so that the disconnector 1 can be easily opened and closed during opening/closing operations.
Even if there is vibration, this is canceled out and the opening/closing angle can be measured accurately. The present invention can be applied to any type of vessel or disconnector to be measured, such as a vacuum vessel or disconnector, an oil-immersed disconnector, an air switch, a disconnector, or the like.

Further, if the movable part of the measuring object or disconnector is made of a conductor and has a sufficient opposing area, there is no need to provide the above-mentioned conductor. As described above, according to the present invention, the length of the gap between the movable part of the shield breakers is measured using an eddy current loss type non-contact displacement meter, and this is expressed on the time axis using an electromagnetic oscilloscope. As a result, the movable part and the measuring tool can be connected in a non-contact manner by changing from the conventional linear connection to a planar connection, and adjustment work such as centering to connect the two during measurement is unnecessary. Measuring work is significantly simplified by simply having them face each other.

In addition, since there is no contact between the movable part and the measuring tool, there is no discontinuity in the opening/closing curve as in the conventional method, making it possible to measure the opening/closing speed extremely accurately. It has an extremely large effect in that it can be fully applied to disconnectors and disconnectors. In addition, since the pick-up coil of the displacement meter is attached to a part other than the movable part, such as the frame of the disconnector being measured, by a fixture, the various vibrations that occur during the opening and closing operations of the disconnector are canceled out. The opening/closing speed can be measured accurately.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIG. 2 is a diagram showing a resonance curve of a pitch-up coil and a tuning circuit of a displacement meter, in which the horizontal axis represents frequency and the vertical axis represents a coupling coefficient. FIG. 3 is a diagram showing the opening characteristic curves of vacuum shield breakers in the conventional device and in the case of the present invention, in which the horizontal axis represents time and the vertical axis represents gap length. FIG. 4 is a perspective view of essential parts showing an example in which the present invention is applied with the vacuum shield and disconnector mounted in the outer box. 1...Shield breaker, 5...Movable electrode rod, 6...Conductor, 7...Eddy current type non-contact displacement meter, 8... ...Pickup coil, 1
4... Electromagnetic oscillograph, d... Gap length.

Claims (1)

[Claims] 1 A measuring device or disconnector equipped with a movable contact and a fixed contact, an eddy current type non-contact displacement meter equipped with a pickup coil, and a device located outside the container of the measuring device or disconnector. An electric conductor that moves in conjunction with the operation of the movable contact, and a frame of the disconnector to be measured, with the pickup coil separated by a predetermined gap in the moving direction of the electric conductor so that the electric conductor is within its magnetic field. a fixture removably fixed to a part other than the movable part; and an electromagnetic oscilloscope that receives the output of the eddy current type non-contact displacement meter and displays the opening/closing speed of the movable contact from the change in the gap length over time. A device for measuring the opening/closing speed of breakers, characterized by comprising: