SU676955A1 - Magnetic field parameter measuring device - Google Patents

Description

one

The invention relates to the field of measurement technology and is intended to measure magnetic field parameters.

Ferrosands containing a core made in the form of a tube wound from permalla are known, a longitudinal field winding having the form of a solenoid into which a core is inserted, a transverse field winding applied onto the core as a toroidal 1.

A disadvantage of the known device is the difference between the demagnetization coefficients (shape factors) in different directions.

The closest to the described technical essence is a device containing a core, covered by two main orthogonal excitation windings, and an alternating current generator 2.

A disadvantage of the known device is low measurement accuracy.

The purpose of the present invention is to improve the measurement accuracy.

The goal is achieved in that a device containing a core covered by two main orthogonal excitation windings and an alternator is additionally introduced with an additional excitation winding covering the core and located orthogonally to the main excitation windings connected to the output of the alternator, as well as the switch and three frequency-selective blocks, the first inputs of which are connected to the corresponding excitation windings, and the second inputs and inputs of the switch are connected to the output of the gene RATOR, the switch output is connected to the first and second main excitation windings, while the outputs of the frequency selective blocks are connected to the second inputs of the frequency selective blocks, and the core is made in the form of a sphere.

FIG. 1 shows a structural diagram of a core with field windings; in fig. 2 is a block diagram of the proposed device; in fig. 3 shows: a plot of the current flowing through the additional field winding (a); plot of current flowing through the main first excitation winding (b); plot of current flowing through the second main excitation winding (c).

The device comprises a housing 1 on which a permallean core 2 is located, a housing 3 of an additional excitation winding 4, a housing 5 of a first primary excitation winding 6 on which a first primary excitation winding is located, a housing 7 of a second primary excitation winding 8 on which a second primary excitation winding is located (see Fig. I), alternator 9, switch 10, frequency selective blocks II, 12 and 13, permallean core 14, optional, excitation winding 15, first excitation winding 16, second novna excitation winding 17 (see. FIG. 2).

The device works as follows.

Current / 1 (see Fig. 3, a), flowing in the winding 15 from the generator 9, is shifted in phase

on - in comparison with the current supplied to the switch 10. Switch 10 is synchronized by pulses from generator 9 so that for one or several periods current / 2 flows (see Fig. 3.6) in winding 16 (and then current / s (see fig. 3.8) in the winding 17. The switching of currents / 2 and / 3 (see fig. 3 b and s) in the windings 16 and 17 is carried out at the times when these currents are equal to 0. As a result, switching currents / r and / h (see figs. 3 a and b) in the volume covered by the excitation windings 4, 6 and 8 creates a saturable field of core 2 rotating field of excitation alternately plane perpendicular to the winding axis 6 and in a plane perpendicular to the coil axis 8.

When a constant field of the signal is applied to the core 2, the second harmonic of the magnetic induction appears, which is proportional to the active field. The amplification and detection of the second harmonic signal is carried out by frequency-selective blocks 11, 12, and 13.

The device is sensitive to magnetic fields in directions coinciding with the axes of the excitation windings 4, 6 and 8.

In the device, the magnitude of the spurious signal, due to the presence of a uniform geomagnetic field, does not depend on the core, which ensures high accuracy of measurement of magnetic field parameters. The presence of a spherical core and spherical excitation windings ensures uniformity of the excitation field and compensation field in the core volume, which reduces the noise level of the proposed device.

Claims (2)

1. A device for measuring the parameters of a magnetic field containing a core covered by two main orthogonal excitation windings, and an alternator, characterized in that, in order to improve the measurement accuracy, an additional excitation winding encompassing the core and positioned orthogonal to the main windings is additionally introduced into it excitation associated with the output of the alternator, as well as the switch and the three frequency selective blocks, the first inputs of which are connected to the corresponding excitation windings, and the second inputs and inputs of the switch are connected to the generator output, the switch output is connected to the first and second main excitation windings, while the outputs of the frequency selective blocks are connected to the second inputs of the frequency selective blocks. 2. The device according to claim 1, characterized in that the core is made in the shape of a sphere. Sources of information taken into account in the examination 1. Afanasyev Yu. V., Studentsov N. V ... Schelkin A. P. Magnetometric converters, devices, installations. L., “Energie, 1972. 2. Afanasyev Yu. V. Ferrozondy, L., “Energie, 1969. ;five YU T.