RU75887U1 - OPTICAL ELECTRONIC SENSOR - Google Patents

Abstract

The utility model relates to electrical engineering, namely to power current sensors. An optical-electronic current sensor consists of a primary converter, a coding unit, an optical communication channel between the high voltage side of the measured current circuit and the ground potential, a receiving unit, and a power supply unit, as well as a set of blocks and means for transferring energy from the earth potential side to the side high voltage. The relationship between the signal transmission from the primary current converter to the receiving unit and the transmission of energy from the power supply to the coding unit is disclosed. The technical result, which is achieved by a useful model, consists in solving the issue of energy transfer from the ground potential to power the coding unit under high voltage, while maintaining the level of isolation and complete galvanic isolation of the high voltage circuit from the ground potential. 1 p. Fs, 1 fig. heck.

Description

The utility model relates to electrical measuring equipment, namely, to high-voltage power current converters, both direct and alternating current.

High voltage current converters based on converting the measured current strength into a luminous flux that varies according to some algorithm and transmitting it through optical channels to a converter having ground potential, with further conversion to an electric quantity proportional to the measured current, are known from the following sources:

1. Adonyev N.M., Afanasyev V.V., Jalalis L.V. 750 kV Optoelectronic Current Transformer with Direct Modulation of Luminous Flux // Electrical Engineering Industry. High-voltage apparatuses, transformers, power capacitors. 1972, No. 6 (15), p. 19, 20;

2. Adonyev N.M., Afanasyev V.V., Karpenko L.N. Optoelectronic transformer of high voltage // Electricity, 1969, No. 11, p. 1-5;

3. Afanasyev V.V., Adonyev N.M., Kibel V.M. and other current transformers. 2nd ed .. L: Energoatomizdat, 1989, pp. 343-380;

4. Afanasyev V.V., Zubkov V.P., Krastina A.D. Optoelectronic current transformers // Electricity, 1970, No. 7, pp. 18-24.

5. Afanasyev V.V., Zubkov V.P., Krastina A.D. Optical current transformers for ultra-high voltage systems // Electricity, 1975, No. 6, p.21-30.

The above sources describe optoelectronic current transformers and current sensors with external modulation using the Faraday effect; optoelectronic current transformers

and current sensors with internal pulse frequency, pulse width and pulse-code modulation of the light flux. The schemes of manufactured and tested experimental and industrial designs are given:

- Optoelectronic current transformer with internal amplitude modulation, designed to measure unipolar current pulses with edges with a duration of at least 50 μs and an amplitude of up to 10 ⁶ A in circuits that do not allow grounding;

- Optoelectronic current transformers with internal amplitude modulation and pulse frequency modulation, designed to operate on AC with a rated voltage of 750 kV, rated current of 2000 A with one channel for measuring current strength and three channels of relay protection;

- An industrial design of an optical-electronic current transformer with internal frequency-pulse modulation of the Tracer type, developed by Allis-Chalmers (USA, 1967), designed to operate on an alternating current network with a rated voltage of 230 kV.

The closest in technical essence to the patented optical-electronic current sensor should be considered described in the third source of the optical-electronic current transformer type "Tracer" company "Allis-Chalmers" (USA).

This apparatus contains a primary converter (electromagnetic current transformer), a rapidly saturable current transformer, a voltage transformer with a high-resistance voltage divider, a power supply unit, an encoding unit, a fiber light guide, a receiving unit, a recording device.

When a high voltage current flows through the primary converter (electromagnetic current transformer), a lower current is obtained at its output, the value of which is proportional to the measured current and suitable for measurement. The coding unit converts the current value received from the primary converter by

a given algorithm into a sequence of light pulses, and directs the light flux through the fiber to the receiving unit, where the light signal is converted back into an electrical quantity proportional to the primary current, which is recorded by the recording device. The electric energy for supplying the coding unit is obtained from the power unit, which in turn receives energy from either a fast saturable current transformer, which is connected in series with the measured current circuit, or from a voltage transformer with a high resistance voltage divider, which is connected in parallel with the measured current circuit. The disadvantages of the known current sensor are:

- The presence of power sources for the coding unit, depending on the voltage or current in the circuit with the measured current;

- The presence of galvanic communication between the circuit with the measured current and the grounded parts through a high-resistance divider.

A useful model solves the problem of creating an optoelectronic current sensor that allows measuring current in a high voltage circuit with one external power source located on the ground potential, with full galvanic isolation of the high voltage circuit from the ground potential.

The technical result, which is achieved by a useful model, consists in solving the issue of energy transfer from the ground potential to power the coding unit of the optoelectronic current sensor under high voltage, while maintaining the level of isolation and complete galvanic isolation of the high voltage circuit from the ground potential.

This is achieved by the fact that instead of a power supply unit, a fast-saturable transformer, a high-resistance divider with a voltage transformer on the high-voltage side, a photocell battery and a voltage stabilizer are introduced in the known optical-electronic current sensor; between the high voltage side and the ground potential are introduced

additional optical channels; at ground potential, an additional power supply and a light emitting battery are introduced. On the ground potential side, the power supply is connected to a battery of light emitters, which are connected through an additional optical channels to a battery of photocells, which, in turn, is connected to a voltage regulator.

The introduction of a power supply with a battery of light emitters, additional optical channels, a battery of photocells with a voltage stabilizer will allow you to abandon other power sources for the coding unit.

The utility model is illustrated by the drawing, where the figure shows a block diagram of a patented optoelectronic current sensor.

The optical-electronic current sensor contains a primary current transducer 1, an encoding unit 2, an optical communication channel 3, a receiving unit 4, a power supply 5, a battery of light emitters 6, additional optical channels 7, a battery of photocells 8, a voltage stabilizer 9.

Optoelectronic current sensor operates as follows. When the measured current flows through the primary converter 1, an electric quantity proportional to the measured current, which enters the coding unit 2, appears on its terminals. In coding unit 2, an electric quantity proportional to the measured current is converted into an information light stream modulated by any known algorithm. The information luminous flux through the optical communication channel 3, which provides the main isolation and galvanic isolation between the high voltage circuit with the measured current and ground potential, is sent from the coding unit 2 to the receiving unit 4, which converts the modulated information light flux according to the inverse algorithm into an electrical quantity, which proportional to the measured current. The power supply 5 serves to power the receiving unit 4 and the battery of light emitters 6, which convert electrical energy into energy light flux. By

additional optical communication channels 7, which also provide basic isolation and galvanic isolation between a high voltage circuit with a measured current and ground potential, the energy light flux is directed to the battery of photocells 8. The battery of photocells 8 converts the energy light flux into electrical energy, which is supplied to the voltage regulator 9. At the output of the voltage stabilizer 9, a stabilized voltage is obtained suitable for powering the coding unit 2.

Thus, an optical-electronic current sensor has been created for measuring the current strength in circuits with any voltage with energy transfer to supply the coding unit to the high voltage side from the earth potential side while maintaining the insulation level and the complete galvanic isolation of the high voltage circuit from the earth potential.

Claims (1)

An optical-electronic current sensor comprising a primary converter, an encoding unit, an optical communication channel between the high voltage side and the ground potential, a receiving unit and a power supply unit, characterized in that an energy transmission channel is used to power the encoding unit located on the high voltage side side of the earth’s potential, consisting of a battery of light emitters, power optical channels, a battery of photodetectors and a voltage stabilizer.