SU996960A1 - Method of measuring strength of non-stationary magnetic field in strip lines - Google Patents

Description

The invention relates to magnetic measurements and can be used to measure pulsed magnetic fields. In stripes & lines

A known method for measuring the intensity of non-stationary magnetic fields with magnetic films is that the magnetic film with a previously recorded aa audio signal frequency is placed in the measured field and this field is determined by the level of the residual signal resulting from the interaction of the field with the film

The disadvantage of this method is low speed and low measurement accuracy.

A method for measuring the intensity of a transient magnetic field in striplines is also known, based on a comparison of the effect of the measured field on the pulse magnetising signal of a thin magnetic film: with a calibrated constant magnetic field parallel to the measured field C}

The disadvantage of the known method is the low accuracy of measuring the instantaneous value of the intensity of the non-stationary magnetic field.

The purpose of the invention is to improve the accuracy of measuring the instantaneous value of the intensity of a non-stationary magnetic field.

The goal is achieved by the fact that according to the method of measurement eg. of the non-stationary magnetic field in the strip lines, based on comparing the effect of the measured field on the pulsed magnetization signal of a thin magnetic film with the action of a calibrated constant magnetic field parallel to the measured field, in a strip line serves

15 current pulse; once after a predetermined period of time after the arrival of a current drop, the other when the current drop is turned off, but in the presence of a constant field.

20

FIG. 1 shows timing diagrams explaining the essence of the method, FIG. 2 is a block diagram of a device implementing the method.

Claims (2)

The device contains a source of 25 current interchanges 1 with a source of additional pulses 2 parsed in place, a thin uniaxial permalloy film 3 placed in the strip line 4 being examined. The method for measuring the intensity of the non-stationary magnetic field Hp in the past, the lines is as follows. Permalloye film 3 with a detachable coil 5 is placed in the area of strip line A under study. From the source of current drop 1. A current drop is supplied to strip line 4 (Fig. 1a), with the number "field of which is selected from line 4 was insufficient to completely saturate permeable film 3. To measure the instantaneous value of the magnetic field at the required time T (Fig. 16 s, strip line 4, an additional current pulse is applied (Fig. 1). Signals in (Fig. 1 ), read from permalloy film 3 in m oment, time C t is proportional to the sum of the measured magnetic field Hn and the additional magnetic field NA. Then the current drop is turned off and turned on from the constant calibrated field NF FIG. 3. differs from the amplitude of the signal (Fig. Ll), registered by the signal recording unit 6 with the current differential on. A gradual change in the constant magnetic field H gives the signal the same 1plitude, which occurred when the magnetic field H was switched on. In this case, the signal is read. It is proportional to the sum of the constant magnetic field Hfi and the additional magnetic field Nd, and the amplitude of the additional magnetic field Nd in both cases of the Measurements is the same. Thus, the corresponding value of the constant density of a constant magnetic field H, | can be set equal to the intensity of the investigated magnetic field H at the time instant g, provided that the characteristic characteristic time of the film's response to a change in the magnetic field is significantly less than the duration of the process under study (). The films have a feic effect, so that using the method achieves a temporal resolution of the order of several nanoseconds. The proposed method provides the ability to measure the instantaneous value of the intensity of a non-stationary magnetic field in nonOCKOBialX lines with an accuracy of no worse than 1% at a time resolution, which is unattainable using other known methods of research of magnetic fields with an accuracy of 10-20%. The proposed method is applicable to the study of the influence of eddy currents and losses at the time of establishing the field, for detecting the pulsed magnetic fields required for precision measurements of the temporal parameters of a wide class of magnetic materials. Claims The method of measuring the strength of a non-stationary magnetic field in strip lines is based on comparing the effect of the measured field on a pulse magnetising signal of a thin magnetic film with a calibrated constant magnetic field parallel to the measured field, characterized in that the accuracy of measuring the instantaneous value of the expansion of a non-stationary magnetic field; a current pulse is applied to the strip line: once after a specified time interval after entering Differential current, the other - with the current drop off, but in the presence of po- hundred nnogo floor. Sources of information taken into account in the examination 1. The author's certificate of the USSR 618705, cl. G01R 33/02, 1976. 2. Krayder and Humphrey. A nanosecond photo set to radiate the magnetization reversal of thin films. - Instruments for scientific research, 1969, I 6, p. 86-87. i i g