SU1092417A2 - Optical electronic voltage transformer - Google Patents

Abstract

OPTICAL ELECTRONIC VOLTAGE TRANSFORMER according to aut. St. || GRG;} m7 G1a No. 646261, characterized in that, in order to improve the measurement accuracy, a source of exemplary low voltage is introduced into it, and the additional optical channel in the Kerr cell is equipped with a plane-parallel capacitor, the plates of which are connected to the potential pole of the sample low voltage and with zero potential tire.

Description

The invention relates to electrical measuring technology and can be used in the measurement of variable and pulsed high voltages.

An optoelectronic voltage transformer is known that contains a monochromatic radiation source, a beam splitter, a polarizer, a cell with a main optical channel connected through a plane-parallel capacitor with a high voltage circuit, and an additional optical channel located outside the electrical path, installed one after the other in the optical path. last field, collecting lens, a screen with a hole located in the focal plane of the lens, the photodetector 1.

The disadvantage of this device lies in the low accuracy of measurement due to the dependence of the transformation coefficient on the temperature and other instabilities of the constant Kerr filling dielectric.

The purpose of the invention is to improve the accuracy of measuring high voltages.

The goal is achieved by the fact that the optoelectronic voltage transformer containing a monochromatic radiation source installed one after the other in the optical path, a beam splitter5 polarizer, a Kerr cell with a main optical channel connected through a plane-parallel capacitor with a high voltage circuit and an additional optical channel placed outside the electric field of the latter, collecting the lens, a screen with a hole located in the focal plane of the lens, a photo receiver, the source of the image The low optical voltage and the additional optical channel in the Kerr cell are equipped with a plane-parallel capacitor, the plates of which are connected to the potential pole of the exemplary low voltage source and to the zero potential bus.

The drawing shows a functional diagram of an optoelectronic voltage transformer.

In the optical path, a monochromatic radiation source 1, a beam splitter 2, a polarizer 3, a Kerr cell 4 with main and additional optical canals passing between the plates of plane-parallel capacitors 5 and 6, a collecting lens 7, a screen 8 with a hole, located in the focal plane of the lens 7, the photodetector 9. The main optical channel of the Kerr cell 4 is located in an electric field of a high-voltage circuit and is connected with it by means of a plane-parallel capacitor 5. It consists of troystva also includes a source 10 of an exemplary low voltage in the electric field of which is placed an additional optical channel Kerr cells 4 by connecting plane-parallel plates of the capacitor 6 with a potential pole of source 10 and bus Zer. potential.

The device works as follows.

The light beam from the monochromatic radiation source 1 is formed by the beam splitter 2 into two parallel beams. These beams pass through polarizer 3, which allows the initial polarization of the light to be established relative to the direction of the applied electric fields, and then through the dielectric fluid filling the 4 Kerr cell. Upon leaving; Kerr cells 4 are both collected by lens 7 and an interference pattern is observed on screen 8 due to the difference in the path of the rays.

Using the field of the exemplary low voltage source 10, the initial interference pattern is established, and when a high voltage circuit is applied to the floor, the interference pattern is shifted due to the additional path difference due to the Kerr effect in the dielectric. If, at the same time, the size of the hole in the screen 8 is comparable to the width of the interference band, the photodetector 9 registers the offset of the interference band as a sequence of pulses.

The magnitude of the measured high voltage is determined by the expression

., km

where Ksd yrH / dH ft coefficient

transformation; Ufi - measured high voltage UH - exemplary low voltage M - number of pulses recorded by photoreceiver 9, bt pins of electrodes of plane-parallel capacitors 5 and 6 Kerr cells 4, included in high and low voltage, respectively, a., D - interelectrode distances in capacitors 5 and 6 cells. Thus, in the proposed device, the influence of a change in the Kerr constant of the filling dielectric on the transformation ratio of the measured parameter is excluded (this expression for determining U the constant Kerr is not included). This circumstance has a positive effect on the accuracy of the measurement of high voltage. Due to the fact that in the proposed device the measurement of high voltage is carried out by determining the exemplary low voltage, which is associated with high voltage through the geometrical dimensions of the plane-parallel capacitors 5 and 6, an exception to the high-voltage standard means is provided for measuring and calibrating. , which makes the device more convenient to operate.

Claims (1)

No. 646261, characterized in that, in order to improve the measurement accuracy, a reference low voltage source is introduced into it, and the additional optical channel in the Kerr cell is equipped with a plane-parallel capacitor, the plates of which are connected to the potential pole of the reference low voltage source and with a zero potential bus. >