SU404030A1 - DEVICE FOR MEASURING THE COMPONENT OF MAGNETIC INDUCTION VECTOR - Google Patents

Description

one

The invention relates to a measurement technique and can be used to simultaneously measure the orthogonal components of a magnetic induction vector in a given volume of space.

The known devices are characterized in that each directional transducer is placed in an individual coil and is orthogonal to one another in a magnetic field. The output signals of the primary converters are fed to amplifying devices, from the output of which the feedback currents are applied to the corresponding coils so that in each primary converter only the longitudinal component of the magnetic induction vector, which coincides with the direction of the magnetic axis of the converter, is automatically compensated.

However, the known devices are characterized by low accuracy due to the influence of the transverse components of the magnetic induction vector.

To improve the measurement accuracy, the proposed device is equipped with orthogonally disposed coils, such as Helmholtz rings, through which feedback currents from the respective transducers are passed so that the longitudinal and transverse components of the variable field are simultaneously and automatically compensated for in the entire volume occupied by the primary converters, and their value depends on the depth of the feedback.

FIG. 1 shows a functional diagram of the proposed device; in fig. 2 is a graph of the evaluation of induction induced in the primary transducer from the transverse field component.

The device contains three pairs of orthogonal coils 1, primary converters 2 and amplifying-converting devices 3. The latter consist of direct conversion channels 4, recording

devices 5 and channels 6 reverse conversion.

The device works as follows. Three pairs of orthogonally arranged coils 1, in the center of which are transducers 2, mounted along the axis of the coils, are placed in a measured magnetic field.

Signals from primary converters are fed to devices 3 and through channels 4 of direct conversion - to recording devices 5, and through channels 6 of inverter - to corresponding pairs of coils 1.

Measurement errors are determined as follows.

The coordinate system O, Y, Z is connected to the axes of the orthogonal coils (see Fig. I), which do not change their spatial position.

Relative to these axes, the magnetic axes of the primary transducers are oriented. The magnetic axis of the primary converter changes in space due to the inadequacy of the amplitude of the field of excitation, three, imperfections of the manufacturing technology of the converters, etc. It is considered that the magnetic axis of the converter has changed its position relative to the longitudinal axis of the coil by an angle a. Let the angle and components of the field BZ and Bx lie in the XOZ plane, as shown in FIG. 2. Based on FIG. 2, the error of mixing the magnetic axis of the converter is determined as follows:

D5x BX-BI-BZ sin a + Bx (l-cos a), (1)

where BX, BZ are the longitudinal and transverse components of the vector field.

In this case, the error from the transverse component of the floor will be

A x- zsina. (2)

Based on FIG. 1 have (equality

(3)

B, BzK,

where BK is the compensation field in the coils created by the feedback current;

/ (, P are transmission coefficients of the direct and inverse transform, respectively.

From expressions (3) find the value of the transverse component of the field acting on the primary transducer

AT

z

(four)

 Bz (l- E),

Bz

l + / ci

where (: l - -K} is the depth of the feedback. Thus, the measurement error due to the transverse field component will be equal to

A5x-5z (l-) sina. (5)

When the value / Cf 100 or | 0.99 measurement error will be significantly less than in known devices.

Subject invention

An apparatus for measuring magnetic induction vector components comprising orthogonal primary transducers of coil directional action and

amplifying-converting devices covered by feedback, characterized in that in order to improve the measurement accuracy, it is provided with orthogonally located coils, such as Helmholtz rings, in the center of which the converters are located, and the coils are connected to corresponding amplifying-converting devices.

AND/

N-,

eleven)

at

L PG