JPS61114170A - Measuring device for lightning surge voltage - Google Patents

Abstract

PURPOSE:To grasp an accidental surge voltage accurately and to take a severe lightning voltage surface measurement by measuring a voltage, which is divided by the 2nd capacitor, by a BSO voltage sensor, and processing a measured value above a specific value by an A/D converter, memory, low-speed D/A converter, etc. CONSTITUTION:A surge voltage when developed on a power line 1 by lightning is divided by series-connected capacitors C1 and C2 between the power line 1 and ground 2 and the voltage divided by the capacitor C2 is converted into a light signal by a BSO voltage sensor 6 capable of observing high-speed variation; and the light signal is transmitted through an optical fiber 8 and converted by a photoelectric converter 10 into an electric signal. Then, when its value exceeds a specific value, an A/D converter 14, memory 16, D/A converter 18 slower than the converter 16, etc., are controlled through a trigger circuit 22 and a timing circuit 24 to grasp the accidental surge voltage through the processing of them, so that the precise lightning voltage surge voltage is recorded on an electromagnetic oscillograph 20, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device for observing and measuring surge voltage on power lines.

[Conventional technology]

Observing surge voltages that occur on power lines.

This is important in determining the point of lightning strike and the degree of glass deterioration.

Figure 2 shows a conventional waveform observation device.B A first capacitor (C1) and a second capacitor are connected between the power line (1) and the ground (2).
capacitors (C2) are connected in series. A surge voltage (3) generated by lightning or the like is divided by a first capacitor (C1) and a second capacitor (C2). The voltage across the second capacitor (C2) is the voltage across the storage tube (4
) will be displayed on the oscilloscope (5). In this way, the surge voltage (3) generated on the power line (1) can be observed.

[Problem that the invention seeks to solve]

However, since surge voltage occurs within a very short period of time, it has been difficult to precisely observe its waveform. Furthermore, since surge voltages occur accidentally, conventional techniques have not been able to completely capture surge voltages.

In view of the above-mentioned problems, it is an object of the present invention to provide a device that properly captures accidental surge voltages and closely observes W4.

[Means for solving problems]

This invention includes a BSO voltage sensor that measures the voltage divided across the @2 capacitor, a VD converter that converts the measured voltage into a digital signal, a memory that stores the digital signal, and a VD converter that converts the digital signal stored in the memory. D/A that converts to analog signals at a speed slower than the conversion speed of the converter
An f converter and display means for displaying the analog signal were provided. moreover.

BSO [A control circuit is provided that operates the 1-width converter, memory, D/A converter, and display means when the voltage measured by the pressure sensor exceeds a predetermined value.

[Effect]

The surge voltage generated on the power line is measured by a BSO [pressure sensor]. This measured voltage is converted into a digital signal by a converter at a predetermined sampling interval.11. Stored in memory sequentially. The stored digital signal is reconverted to an analog signal by a D/A converter at a rate slower than the conversion rate of the VD converter. Therefore, the reconverted analog signal has a time axis expanded compared to the waveform of the measured voltage. This analog signal is displayed on a display device to observe the surge voltage. In addition, the control circuit is BSO
Each circuit is controlled to display only when the voltage measured by the voltage sensor exceeds a predetermined value.

〔Example〕

FIG. 1 shows an embodiment of the present invention. The first and second capacitors (C1) are connected between the power line and the ground (2).
- (C2) are provided in series. 1st/20th J
ml,/amp (C1)-(C2) (1) Value C, B
It is determined in consideration of the input withstand voltage and surge voltage of the SO sensor (6).

Capacitor (C1)1. t 1000pF~4000p
F. It is appropriate that the capacitor (C2) is 1xF to 4μF. In this example, the capacitor (cl) was 20009F, and the capacitor (C2) was 4 μF.

When a surge voltage (9) occurs on the power line 11) due to lightning, etc., this surge voltage (3) is transferred to the capacitor (C1) (
C2) and measured by the BSO voltage sensor (6). A BSO (bismuth silicon oxide) voltage sensor (6) generates an optical signal corresponding to this surge voltage (3) and sends it to an optical fiber (8). The optical signal is converted into an electrical signal by the O/E converter Q (I).It has excellent noise resistance because it uses an optical fiber (8) as a transmission path.Electricity from the O/E converter OQ The signal is converted to an appropriate level by the input amplifier (2) and input to the VD converter o41.The VD hair converter a◆ receives the start signal and clock signal from the timing circuit ■, and converts it from the input amplifier (converter). The digital signal is converted into a digital signal at a predetermined sampling interval.This digital signal is sequentially stored in the memory 00.The digital signal stored in the memory OQ is converted back into an analog signal by the D/A converter (7). The conversion speed at this time is slower than the conversion speed of VD converter o4. Therefore,
The time axis of the reconverted analog signal is expanded than the time axis of the surge voltage waveform, allowing for more precise observation over time. The reconverted analog signal is 1
For example, it is recorded by an electromagnetic oscillograph (7).

The output of the O/E converter OQ is also applied to a trigger circuit. The trigger circuit Shu is the 0/E converter Of
) should generate a trigger when the output exceeds a predetermined value. In response to this trigger, the timing circuit (incorporated) sends a start signal, clock signal, etc. to the VD converter 04, etc., and starts the above-mentioned recording. That is, in this embodiment, the control circuit is composed of a trigger circuit and a timing circuit. The electromagnetic oscilloscope (1) enters a standby state after recording only the predetermined capacity of the memory aQ. If the power of the O/E converter α exceeds the predetermined value again, a new recording starts.

As described above, recording is performed every time a surge voltage (3) occurs.

It would be convenient for observation if the time was recorded at the same time as the waveform.

〔Effect of the invention〕

According to the present invention, it is possible to appropriately display surge voltages that occur accidentally, and it is possible to perform more precise observation than with conventional techniques. Furthermore, since the BSO sensor is used, high-speed changes can be observed, and there is no need to supply power to the automatic sensor, making it economical.

[Brief explanation of drawings]

FIG. 1 shows an embodiment of the present invention, and FIG. 2 shows a conventional measuring device. (C1) is the first capacitor, (C2) is the second capacitor, (υ is the power line, (6) is the BSO voltage sensor, (
8) is optical fiber, Q (l is 0/E converter, 04)
it VD converter. 04G is a memory, (to) is a D/A i converter, 4 is an electromagnetic oscilloscope, ■ is a trigger circuit, and (c) is a timing circuit. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Claims] (1) The first wire connected in series between the overhead line and ground.
a second capacitor, a BSO voltage sensor that generates an optical signal based on the voltage across the second capacitor connected to the ground side, an optical fiber that transmits the optical signal output by the BSO voltage sensor, an optical signal transmitted by the optical fiber. an O/E converter that converts the analog signal from the O/E converter into a digital signal, an A/D converter that converts the analog signal from the O/E converter into a digital signal, a memory that stores the digital signal from the A/D converter, and a memory that stores the digital signal from the A/D converter. A D/D converter that converts the stored digital signal into an analog signal at a speed slower than the conversion speed of the VD converter.
Display means for displaying analog signals from the A converter and D/A converter; when the analog signal from the O/E converter exceeds a predetermined value, the A/D converter, memory, D/A converter, A lightning surge voltage measuring device comprising: a control circuit for operating a display means.