JPH01191069A - Surface charge measuring instrument - 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 [Field of Industrial Application] The present invention relates to a device that automatically measures the amount of charge charged on the surface of an insulator of, for example, high voltage equipment.

[Conventional technology]

FIG. 3 is a schematic diagram of a conventional insulator surface charge measuring device shown in the report of the Central Research Institute of Electric Power Industry: 786001. Probe 2 is arranged so that it can be raised and lowered.
This arrangement allows the tip of the insulator 22 to be opposed to all measurement points on the surface of the insulator 22, which is the object to be measured, as it rotates.

When the probe 21 is opposed to a measurement point on the surface of the insulator 22, the induced charge on the probe 21 that is electrostatically induced by the charge on the insulator 22 is detected as a voltage value by the voltage measuring device 24. In addition, the positioning points of the pedestal 24 are detected based on the forward and backward movement amount and the vertical movement amount of the probe 21 by the positioning device 23, and the geometrical relationship between each measurement point on the insulator 22 and each positioning point of the probe) l is detected. It is now possible to obtain location data.

The surface of the insulator 22 is divided in advance into, for example, a base pattern, and the probe 21 is placed at a predetermined position within each divided area or at each intersection of vertical lines and horizontal lines for dividing each area. Sequentially face each other in terms of distance and angle, and obtain each voltage data and position data at that time.

The output of the probe 21 is measured as a voltage shared by a low-loss capacitor built into a voltage measuring device 26, which is a vibratory capacitive voltmeter.

The voltage data and position data for all measurement points obtained in this way are input into a separately used calculator, and the amount of charge for all measurement points on the surface of the insulator 22 is calculated by a measurement data processing program.

That is, first, based on the position data, the coupling coefficient between the surface of the insulator 22 and the probe 21 is calculated, and by solving an equation using the amount of charge on the surface of the insulator 22 as an unknown, each measurement point on the surface of the insulator 22 is calculated. Find the amount of charge.

[Problem to be solved by the invention]

By the way, with such conventional devices, the position data of each detected measurement point and probe positioning point, as well as the voltage data output from the probe, are input into a separately prepared computer, and the data is processed by a pre-prepared data processing program. Therefore, the amount of charge on the surface of the insulator.

This method has the disadvantage that the work required to obtain a charge distribution map is extremely troublesome.

The present invention was made in view of the above circumstances, and its purpose is to calculate the amount of charge at each measurement point on the surface of an insulator, based on the position data of the probe, and the output voltage data of the probe. An object of the present invention is to provide a surface charge measuring device that can automatically measure a surface charge.

[Means to solve the problem]

The surface charge measuring device according to the present invention includes a probe that is positioned opposite to each measurement point on the surface of an object to be measured and outputs an electric signal corresponding to the amount of charge at the measurement point, and a probe positioned opposite to each measurement point. a position measuring device for determining the position of the probe, and a coupling coefficient between the amount of charge at the measuring point and the probe output based on the position data determined by the position measuring device of the probe, and
The measuring device includes an arithmetic device that calculates the amount of charge at each measurement point on the surface of the object to be measured based on the coupling coefficient and the probe output.

[Effect]

According to the present invention, this makes it possible to directly determine the amount of charge on the insulator or its distribution using the arithmetic unit connected to the probe.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on drawings showing embodiments thereof.

FIG. 1 is a block diagram of a surface charge measuring device according to the present invention (hereinafter referred to as the device of the present invention), in which 1 is a probe;
indicates the insulator that is the object to be measured. The entire measurement surface of the insulator 2 is divided into small regions in the shape of a base grid, and each small region 2a or the intersection point 2b of each division line (hereinafter referred to as a measurement point) is separated from this by a required distance. Measurement is performed with the probes 1 facing each other.

Since the measurement is performed by assuming that the charge density distribution within the measurement point is constant, it is necessary to set the size of the measurement point appropriately in order to improve the measurement accuracy. However, if it is made smaller than necessary, the amount of calculation required to calculate the coupling coefficient becomes enormous.
It is desirable to take both factors into consideration and to determine it appropriately. In addition, if the distance between the measurement point and the probe 1 is too large, the measurement accuracy will be lowered due to the influence of the amount of electric charge around the measurement point, and if it is too small, the distance between the insulator 2 and the probe 1 will be reduced. There is a risk of electrical discharge occurring, and it is determined appropriately by taking both of these into consideration.

The positioning of the insulator 2 at each measurement point is performed by a probe positioning device 12 and a driving unit 11 for a pedestal and a lifting platform (not shown).
When the probe 1 is positioned so as to face the commanded measurement point at a predetermined distance and angle, data such as distance and angle and command data of the probe positioning device 12 are used for position measurement. The data is taken into the device 13, and the geometric position data of the probe 1 and the insulator 2 is calculated and input into the storage section (or recording device) 16.

Further, each time the probe 1 is positioned with respect to a measurement point, a voltage which is a probe output corresponding to the amount of induced charge induced in the probe 1 is measured by a voltage measuring device 14, and an analog-to-digital (A/D) converter 15 The signal is converted into a digital signal and similarly input to the storage section 16 as a voltage.

17 is a surface charge calculation device which reads position data from the storage unit 16 and calculates a coupling coefficient matrix (P i, > between the amount of charge on the surface of the insulator 2 and the probe output;
Then the coupling coefficient matrix <Pi,>, the voltage data q! for each measurement point! (i = 1 to m) and the amount of charge on the surface of the insulator (this is called the charge density σ).

(denoted by j = 1 to m)) is the unknown quantity according to the following equation (1), calculate the amount of charge at each measurement point on the surface of the insulator, input this to the output device 18, and output the charge from the output device 18. It is designed to output distribution diagrams, equal charge distribution diagrams, etc.

Pij in the above formula is a coefficient that gives the output (induced charge) of the probe at point i when there is a unit charge at the jth measurement point,
That is, it is a coupling coefficient.

Next, the amount of charge (charge density) on the surface of the insulator by the device of the present invention
The measurement process will be explained according to the flowchart shown in FIG.

Measurement points are determined in advance with appropriate precision on the surface of the insulating material, and the mount and lifting platform of the probe l are operated based on the position command signal from the probe positioning device 12 to align the tip of the probe 1 with the measurement point and the predetermined position. They are made to face each other at a predetermined angle with a gap between them (step ■). The position of the probe 1 is measured based on the data for positioning at that time (Step 2), and is stored (or recorded) in the storage unit (or recording device f) 16 (
Step ■).

Further, the output voltage corresponding to the amount of induced charge generated in the probe is taken into the voltage measuring device 14 (step ■), and after being converted into a digital signal by the 67-port converter 15 (step ■), this is also transferred to the memory (or The data is stored (or recorded) in the recording device (recording device) 16 (step (2)).

This is regarded as one cycle, and step (■) is repeated for all measurement points. After that, the coupling coefficient Pij between each probe output and the charge I (charge density) of each measurement point on the insulator surface is determined in the calculation device 17 (step (■)). , its coupling coefficient matrix < P i,) is created, and after completing the creation of the coupling coefficient matrix for all measurement points (step
Solve the equation (step [phase]), create a charge distribution diagram 1 equal charge distribution diagram on the output device 18, or print it, and complete the measurement (step ①).

〔Effect of the invention〕

As described above, in the device of the present invention, the output data of the probe and the position data of the probe are probed.

Since the amount of charge on the surface of the object to be measured is directly calculated by inputting it to the arithmetic device connected to the position measuring device, all work including calculation of the amount of charge at the measurement point and calibration of the data necessary for this calculation can be performed. The present invention has excellent effects such as being able to perform the process automatically.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the device of the present invention, FIG. 2 is a flowchart showing the process of measuring the amount of charge by the device of the present invention, and FIG. 3 is a schematic diagram of the conventional device. 1... Probe 2... Insulator 11... Drive section 12... Probe positioning device E 13...
Position measuring device 14...Voltage measuring device 15...A
/D converter 16...Storage unit 17...Surface charge calculation device 18...Output device Note that in the drawings, the same reference numerals indicate the same or equivalent parts. Agent Masuo Oiwa Procedural amendment (spontaneous) June 1930 to May 26 1, case 0 display Patent application No. 17802 No. 1983,
Name of the invention Surface charge measuring device 3, Representative of the person making the amendment Moriya Shiki 5, "Detailed description of the invention" column of the specification to be amended, Drawing 6, Contents of the amendment 6-1 "Details of the invention"``Explanation'' column (1) In the 2nd page of the specification, line 1, the phrase ``mount 24'' is corrected to ``mount 27.'' (2) In the first line of page 3 of the specification, the phrase "pressure measuring device 26" is corrected to "pressure measuring device 24." (3) On page 3, line 4 of the specification, the phrase "separately used calculator" is corrected to "separately prepared calculator." (4) On page 4, line 12 of the specification, the phrase "electric charge amount and pro at the measuring point" is corrected to read "measuring point and pro". (5) Formula (1) on page 7, line 8 of the specification is corrected as follows. 6-2 Correct as shown in the attached sheet of Figure 3 of the drawing.

Claims (1)

[Claims] 1. Positioned opposite each measurement point on the surface of the object to be measured,
A probe that outputs an electrical signal corresponding to the amount of charge at a measurement point, a position measurement device that determines the position of the probe facing each measurement point, and a position measurement device that determines the position of the probe facing each measurement point. A surface comprising: an arithmetic device that calculates a coupling coefficient between the amount of charge and the output of the probe, and calculates the amount of charge at each measurement point on the surface of the object to be measured based on the coupling coefficient and the output of the probe. Charge measuring device.