SU913288A1 - Device for producing magnetic field - Google Patents

Description

The invention relates to magnetic * measurements and experimental physics and can be used to create a stable magnetic field.

A device for creating a stable magnetic field, comprising a ferromagnetic screen, a system of coils in a screen connected to a stabilized current source, and a magnetic field stabilizer based on a quantum optical B ^ magnetometer, whose magnetically sensitive element and feedback winding are located inside the screen, are known.

The disadvantage of this device is the low efficiency of suppression of inhomogeneous magnetic interference.

A device for creating a magnetic field in a device for determining the electric dipole moment of a neutron, including a ferromagnetic screen, a system of windings in a screen connected to a stabilized current source and a stabilizer

2

magnetic field with a magnetically sensitive element system and feedback winding in the screen.

The device is effectively protected from non-uniform magnetic interference with an amplitude of no more than 10 * ⁵ O. Thus, fluctuations of the magnetic field in a band of 0.03 “

0.1 Hz does not exceed 10 " ⁷ E. Closely located from the device of the source of magnetic interference (physical installation, bridge crane, and so on) interfere with the screen with an amplitude of more than 1E.

The purpose of the invention is to improve the noise immunity of the device.

The goal is achieved in that the device for creating a magnetic field containing a ferromagnetic screen, a system of windings in the screen connected to a stabilized current source, and an electronic unit of a magnetic field stabilizer with a system of magnetically sensitive elements and feedback winding inside the screen,

913288

administered compensation winding, connected to an electronic unit in parallel stabilizer feedback winding with a magnetic field inside the compensation winding, HA Board ₅ opposite to the magnetic field feedback winding, and a further electronic control unit of the stabilizer with independent feedback coil and w nym magnetosensitive element disposed inside 'compensation winding.

The drawing shows a diagram of the device.

The device comprises a ferromagnetic, 5 ny screen 1, the system of coils 2, 3 stabilized power current magnetosensitive element system 4, the electronic unit 5 of the stabilizer, the feedback winding 6, com- ₂₀ lensatsionnuyu ombotku 7> magnetically element 8 additional electronic stabilizer block matching unit 9, additional electronic unit 10 stabilization - ₂₅

torus, 11 feedback winding additional electronic stabilizer unit.

The device works as follows. _thirty

Using the matching unit 9, the device is adjusted so that the magnetic field of the compensation winding 7 compensates for the magnetic field of the feedback winding 6 at the location of the magnetically sensitive ³⁵ element 8 of the additional electronic unit 10 stabilizer. As a result, the additional electronic unit 10 of the stabilizer operates independently of the electronic unit 5 of the stabilizer and under the action of stationary random noise for the area where the magnetically sensitive element 8 of the additional electronic unit 10 of the stabilizer is located, ⁴³

The following relationship holds true:

--_ + D

No. + KDO) T

50

where is the spectral density of the uncompensated additional electronic unit 10 of the stabilizer of magnetic field fluctuations, А ^ Н _м (ии) и - the spectral density of magnetic interference inside the screen 1 and non-magnetic interference

in the circuit of the additional electronic unit 10 stabilizer, respectively, Kd (ΐω) is the complex transfer coefficient of the open circuit of the additional electronic unit 10 stabilizer.

For the region of space where the magnetically sensitive element 4 is located, the relation consistent with (1) is

.0 "Λ ι | / (· Ιιι \

Schi>) = - Mr

ΪΜΰυ)) ⁰ - ⁿ Ψ + Μϊω)

, {£)

where & Ή (W) is the spectral density of the average magnetically sensitive elements at locations of 4 unbalanced by the stabilizer of the electronic unit 5 of the stabilizer magnetic field fluctuations, & ^ _Η (ω) is the spectral density of non-magnetic interference in the circuit of the electronic block 5 of the stabilizer.

K (ϊ (a)) is the complex transfer coefficient of the open circuit of the electronic unit 5 of the stabilizer.

The noise immunity of the device, defined as the ratio of the maximum compensated amplitude of the magnetic interference outside the screen 1 to non-magnetic in the circuit of the electronic unit 5 of the stabilizer for this device, is equal to

g = And + * <* "> · MM’

where K _e (1st) is the screening factor of screen 1, which is 1 + Cd ((ω) ίτπ3χ times greater than the noise immunity of the known device.

We present the results of a device test in the 0.003 Hz band when the electronic components of the stabilizer are made on a single magnetometer with a $ 2 ~ signal. In this case (1 + Κ (ί and)) (GLS (x = (1 + Cd (ϊ <l>) Ιχηαχ *

% 500, for a five-layer screen

240 and the device suppresses magnetic interference 0.1 Oe

up to the value = "Ί ^ Η '(ω) ~ nd 2-10 O.

Thus, the proposed device effectively suppresses large-amplitude magnetic interference.

Claims (1)

Claim A device for creating a magnetic field containing ferromagnetic screen, screen winding system, 913288 five connected to a stabilized current source, and an electronic unit of a magnetic field stabilizer with a system of magnetically sensitive elements and a feedback winding inside the screen, characterized in that, in order to improve the noise immunity of the device, a compensation winding connected to the electronic unit stabilization is introduced into it the torus is parallel to the feedback winding with a magnetic field inside the compensation winding directed opposite to the magnetic field of the feedback loop, and an additional electronic stabilizer unit with independent feedback winding and a magnetically sensitive element located inside the compensation winding.