SU1265627A1

SU1265627A1 - Device for contactless measurement of current intensity

Info

Publication number: SU1265627A1
Application number: SU843810551A
Authority: SU
Inventors: Александр Владимирович Плошинский
Original assignee: Предприятие П/Я А-1742
Priority date: 1984-11-06
Filing date: 1984-11-06
Publication date: 1986-10-23

Abstract

Изобретение относитс к области электроизмерительной техники. Может использоватьс s электронике и экспериментальной физике. Цель изобретени - повышение точности и чувствительности бесконтактного измерени тока, достигаетс за счет использовани дополнительного одновиткового трансформатора. Устройство содержит соосно расположенные одновитковые трансформаторы 1 и 2 тока, охватываю1цие участок 3 измерительной цепи, : вторичную обмотку 4, нагруженную на сопротивление 5, усилитель 6, регистратор 7, цепь отрицательной обратной св зи, состо счую из резистора 8 и дополнительной обмотки 9 трансформатора 1, дополнительную цепь обратной св зи , состо щую из резистора 10 и втори-о S 2. чной обмотки 11 трансформатора (Л 1 ил. ьо. о сд Од to The invention relates to the field of electrical measuring equipment. S electronics and experimental physics can be used. The purpose of the invention is to improve the accuracy and sensitivity of contactless current measurement, achieved through the use of an additional single-turn transformer. The device contains coaxially located single-turn transformers 1 and 2 of the current, covering the section 3 of the measuring circuit,: secondary winding 4, loaded on resistance 5, amplifier 6, recorder 7, negative feedback circuit, consisting of a resistor 8 and additional winding 9 of transformer 1 , an additional feedback circuit, consisting of a resistor 10 and a secondary S2. of the transformer's 11 winding (L 1 or.

Description

Изобретение относится к электроизмерительной технике и может быть ис- _: пользовано в электронике и экспериментальной физике.The invention relates to electrical engineering and can be used _to: use in electronics and experimental physics.

Цель изобретения - повышение точности и чувствительности бесконтактного измерения тока за счет использования дополнительного одновиткового трансформатора. ЮThe purpose of the invention is to increase the accuracy and sensitivity of non-contact current measurement through the use of an additional single-turn transformer. YU

На чертеже представлена схема предлагаемого устройства для бесконтактного измерения силы тока.The drawing shows a diagram of the proposed device for non-contact current measurement.

Устройство содержит два соосно ·, расположенных одновитковых трансфор- 15 матора 1 и 2 тока, охватывающих участок 3 измеряемой цепи. Вторичная обмотка 4 трансформатора тока нагружена на сопротивление 5, подключена ко входу усилителя 6, выход которого со- 20 единен с регистратором 7. К выходу усилителя 6 подключена цепь отрицательной обратной связи, состоящая из резистора 8 и дополнительной-обмотки ₍9 трансформатора Г. Устройство содер- 25 ,жит дополнительную цепь обратной свя[зи, состоящую из резистора 10 и вторичной обмотки 11 трансформатора 2 ; тока.The device contains two coaxial · located single-turn current transformers 15 and 1, covering section 3 of the measured circuit. The secondary winding 4 of the current transformer is loaded with resistance 5, connected to the input of the amplifier 6, the output of which is 20 connected to the recorder 7. A negative feedback circuit consisting of a resistor 8 and an additional winding ₍ 9 of the transformer 9 is connected to the output of the amplifier 6) contains 25, there is an additional feedback circuit consisting of a resistor 10 and a secondary winding 11 of transformer 2; current.

Устройство работает следующим об- эд разом.The device operates as follows.

Измеряемый ток, протекая через отверстие магнитопровода трансформатора 1 тока, индуцирует во вторичной об- 35 мотке 4 ЭДС, выделяемую на нагрузочном сопротивлении 5 и усиливаемую \ усилителем 6. С выхода усилителя 6 сигнал, пропорциональный измеряемому току, поступает на регистратор 7 и в две цепи обратной связи. Первая цепь отрицательной обратной связи (резистор 8 и обмотка 9 трансформатора 1) обеспечивает расширение частотной характеристики трансформатора 1 тока. При помощи второй цепи обратной связи трансформатор 2 тока вносит в участок 3 измеряемой цепи ЭДС равную и противоположную по знаку ЭДС, вносимой в этот же участок трансформатором 1 тока при процессе измерения. Направление и величина тока в обмотке устанавливается так, чтобы ЭДС, наводимая обмотками 4, 11 и 9 в участке 3, была бы равна нулю. В этом случае методическая погрешность будет равна нулю.The measured current, flowing through the hole of the magnetic circuit of the current transformer 1, induces an EMF in the secondary winding 4, which is emitted at the load resistance 5 and is amplified by the amplifier 6. From the output of the amplifier 6, a signal proportional to the measured current is fed to the recorder 7 and into two circuits feedback. The first negative feedback circuit (resistor 8 and winding 9 of transformer 1) provides an extension of the frequency response of current transformer 1. Using the second feedback circuit, the current transformer 2 introduces into the section 3 of the measured EMF circuit equal and opposite in sign of the EMF introduced into the same section by the current transformer 1 during the measurement process. The direction and magnitude of the current in the winding is set so that the EMF induced by the windings 4, 11 and 9 in section 3, is equal to zero. In this case, the methodological error will be zero.

Claims

The invention relates to electrical measuring equipment and may not be used in electronics and experimental physics. The purpose of the invention is to improve the accuracy and sensitivity of contactless current measurement through the use of an additional single-turn transformer. The drawing shows a schematic of the proposed device for the beacon-measuring current measurement. The device contains two coaxially. located single-turn transformers 1 and 2 current, covering area 3 of the measured circuit. The secondary winding 4 of the current transformer is loaded on the resistance 5, connected to the input of amplifier 6, the output of which is connected to the recorder 7. To the output of amplifier 6 a negative feedback circuit is connected, consisting of a resistor 8 and an additional winding 9 of the transformer 1. The device contains An additional feedback circuit consisting of a resistor 10 and a secondary winding 11 of a current transformer 2 is living. The device operates as follows. The measured current, flowing through the aperture of the magnetic circuit of the current transformer 1, induces in the secondary winding 4 EMF separated at the load resistance 5 and amplified by i amplifier 6. From the output of amplifier 6, a signal proportional to the measured current is fed to the recorder 7 and two feedback loops. The first negative feedback circuit (resistor 8 and winding 9 of transformer 1) provides for the expansion of the frequency response of current transformer 1. Using the second feedback circuit, the transformer 2 of the current introduces in the section 3 of the measured circuit an emf equal to and opposite in sign to the emf introduced into the same section by the transformer 1 of the current during the measurement process. The direction and magnitude of the current in the winding is set so that the EMF induced by the windings 4, 11 and 9 in section 3 would be zero. In this case, the methodical error will be zero. The invention is a device for contactless measurement of current, containing a single-turn current transformer, the signal winding leads which through a load resistance are connected to the amplifier inputs, the first winding through the first current reference resistor is connected to the output of the amplifier and to the recorder input, and the second output is connected to a common bus, different in order to increase the accuracy and sensitivity of the measurements, an additional single-turn current transformer was introduced into it, the first output of the secondary winding to The second resistor is costly connected to the amplifier output, and the second to the common bus.