FI58840C - ADJUSTMENT OF ORGANIZATION FOR THE INTRODUCTION OF ICKE-EQUIVALENT PROSPECTION PAO HALL-SPAENNING - Google Patents

Description

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Wa w 11 utlAgg NIN GSSKRI FT 5884ϋ C Patent .Tiyonnetty 10 04 1901 ”Patent meddelit> Ss (51) Kv.ik.3 / h * t.a3 G 01 E 53/06 // H 01 L 43/06 ENGLISH— FINLAND (») PMMttlhtkcmu * - PKMttan« ekiiln | 263/71 (22) HakamlipiM - Antttknlnpdai 01.02.71 '' (23) Alkupilvft - Glftlfhatsdai 01.02.71 (41) Tullut | outside the shield - Bllvlt offwitlif 03.08.71

National Board of Patents and Registration (44) NihUvilulp ™ |. k «UL | uiic * u„ pvm. -

Patents and Registration of Amekan uti »jd och uti. * Krift« n public · ™ * 31.12.80 (32) (33) (31) Requested «uolkeui — eailrd prlorlm 02.02.70 18.08.70 USSR (SU) 13953 ^ , 1U69319 (71) Institut Elektrodinamiki Akademii Nauk Ukrainskoi SSR, Brest-Litovsky Prospekt 102, Kiev, USSR (SU) (72) Sergei Glebovich Taranov, Kiev, Voldmir Vasilievich Braiko, Kiev,

Anatoly Danilovich Nizhensky, Kiev, Vladimir Petrovich Belousov,

Kiev, Dmitry Vasilievich Kovalchuk, Zhitomir, Isaak Pavlovich Grinberg, Zhitomir, Evgeny Evstafievich Laschuk, Zhitomir, USSR (SU) (7M Oy Kolster Ab ($ 4) Method and apparatus for eliminating the effect of non-DC potential voltage on Hall voltage ordning för eliminering av icke-equipotentialspänningseffekten pä Hall-spänning

The present invention relates to electrical measurements and in particular to a method and apparatus for eliminating the effects of a non-DC potential voltage from a Hall voltage, which method is based on the irreversible (non-reciprocal) operation of this Hail generator and can be used in Hall-dependent devices.

In previously known cases, methods are already known for eliminating the effect of this non-equipotential voltage at the Hall voltage, which can be arbitrarily divided into three different categories.

One class of methods is based on balancing a non-DC potential voltage in a Hall generator when there is no magnetic field in place, essentially in the same way as what an out-of-equilibrium voltage would be compensated for in a four-branch bridge circuit. The second class of methods is based on reversing this non-DC potential voltage by an additional magnetic field adapted to act on the Hall generator. The third category of these methods includes those based on the equalization of the proportion of this non-DC potential voltage with the opposite voltage applied to this 2,58840

To the output circuit of the Hall generator. (Compare, e.g., Mazurov M.Ye., "Electronic Devices Using a Hall Generator and Magnetic Resistors," TsNIIPI, Moscow 1965).

One disadvantage of previously known methods is the very poor accuracy in removing the effect of the non-DC potential voltage on the Hall voltage due to variations in the non-DC potential voltage being compensated in each case due to time and temperature instability in this Hall generator and compensating circuit itself. .

Another disadvantage of previously known methods is that it is impossible to determine the true magnitude of the magnetic field acting on this Hall generator, because in many cases this non-DC potential voltage cannot be separated from the actual Hall voltage.

Another disadvantage of previous methods is that they require a lot of time to compensate for this non-DC potential voltage, which in fact hinders or makes it completely impossible to measure and record their magnetic and electrical properties, which vary faster than this non-DC potential voltage. This is especially the case for Hall generators that use AC control, because in this case this non-DC potential voltage is a complex quantity and therefore has two components, one in phase and the other at 90 ° off, both of which must be maintained.

Another disadvantage of the previously known methods is that they do not allow the automation of this actual method of balancing this non-DC potential voltage when this Hall generator is affected by a magnetic field.

One disadvantage common to both of the latter classes of methods is that it requires the use of additional sources of magnetic and electric fields, respectively, in order to provide a balancing voltage. Another disadvantage of these last two classes of methods is that variations in the control current of this Hall generator inevitably interfere with the balancing of this non-DC potential voltage.

Previously, devices have also been known for eliminating the effect of this non-DC potential voltage on this Hall voltage by implementing the methods listed above. In order to implement the first of the method classes, an adjustable resistor is placed in a particularly simple case, placed between the adjacent electrodes of the Hall generator and adjusted so that the non-DC potential voltage is fully balanced, which corresponds to restoring balance to the bridge circuit, which is the counter circuit of the Hall generator.

One disadvantage of these previously known devices is their instability in time and temperature. Another disadvantage is that these balancing parts require careful adjustment during measurement and recording, which means even more waste of time. Finally, but by no means 3,58840, they are inconvenient to handle and cannot be used in digital meters because they do not meet their requirements for accuracy and response speed.

The object of the present invention is to eliminate the above-mentioned drawbacks.

It is an object of the present invention to obviate the effect of a non-DC potential voltage on a Hall voltage and to provide an apparatus for carrying out this method, characterized in that the Hall generator is supplied with control current alternately through one of two pairs of opposite electrodes and the true magnitude of the voltage can be estimated from the arithmetic mean of the magnitudes of the voltages present in at least two consecutive output marks.

The invention also relates to a device in which a pair of opposite electrodes 1 of a Hall generator is connected to a supply source and another pair of opposite electrodes is connected to a Hall voltage detector, characterized in that it includes a switch by means of which pairs of opposite electrodes are alternately connected to the Hall voltage detector. the input source.

The invention can be better understood from the following description of a preferred embodiment thereof, read in conjunction with the accompanying drawings, in which: Figures 1 and 1b represent a Hall generator as an irreversible (non-reciprocal) four-pin (two-circuit) circuit according to the present invention; Fig. 2a is a block diagram of an apparatus for eliminating the effect of a non-DC potential voltage from a Hall voltage in accordance with the present invention; Figures 2b and 2c show two switch contact arrangements according to the present invention; Figures 3 and 3b are waveforms of the currents and voltages which affect the device of Figure 2a when a DC and AC control current is used in the Hall generator, respectively, in accordance with the present invention.

Referring now to Figure 1a, when the Hall generator 1 is energized by supplying current I to one of two pairs of opposite electrodes, e.g. through pairs 2 and 3, and when this generator is not affected by any magnetic field, voltage is applied across electrodes k and 5 of this second pair. this is due to the fact that the electrodes in question are connected to points of different potentials on the generator leaf I. This voltage can be called the non-equal potential voltage and can be denoted U ^. The magnitude of this voltage Up depends on the resistivity of this generator material and is proportional to the magnitude of the control current.

11 58840

As for the non-DC potential voltage, this Hall generator is a reversible (riprocratic) circuit (its mating connection may be in the form of a conventional four-pronged bridge) while with respect to the Hall voltage e „it is not reversible.

of

For a better understanding, reference should be made to Figure 1a, which shows a square isotropic Hall generator using similar electrodes.

This generator is supplied with current by means of a control current through opposite electrodes 2 and 3, this happening from the direction of the electrode 3 to the electrode 2. The dashed line represents the path of the negative charge carrier (electron). Provided that the vector of magnetic induction is located in the plane of this drawing, then according to the right-hand rule, the electrode U should be negative and the electrode 5 positive (these corresponding polarity signs are shown inside the circle in the drawing).

Suppose now that the non-DC potential voltage acts in the opposite direction (the signs of its polarity are shown in small squares). This is because, as follows from the bridge-type equivalent circuit for this, the Hall generator flux has a lower resistance of the branch than that of the branch while both other branches have the same resistance value (γ ^ _ ^ = r ^^) ·

Suppose now that the magnetic induction vector is in the same direction as before and that the generator 1 receives a control current I through the electrodes 1 and 5, this acting from the electrode 5 to the electrode in the h direction, i.e. in the same direction as the Hall voltage. In this case, according to Fig. 1b, the Hall voltage across the electrodes 1 and 2 will act in the opposite direction (polarity signs for this Hall effect are shown inside the circles in the figure) than the control current in the first case (compare Fig. 1a), which is convincing proof that the Hall generator does not no reversible circuit. Since of the resistance values i * 2-5 <r2-U is a ^ ^ trodi 2 at a higher potential than the electrode 3 and the non-equipotential overvoltage U has the same polarity as the Hall voltage e.

P H

Since in the second case the direction of the current is different from what the non-DC potential voltage affects in the first case, it follows that the Hall generator is a reversible circuit with respect to the non-DC potential voltage. Thus, in the first case, the magnitude of this output voltage from this generator can be expressed by Equation 1.

UI | = I eH - Up I (I) and in the second case u21 *! «H + up I ^ (2>

Adding these two voltages together results in a voltage whose average is proportional to the Hall voltage alone and which is independent of the non-5 58840 DC potential voltage, provided that | e ^ j ^ | |. According to algebraic summation rules, if e S U I, the average of the sum of these two characters should

1 π I x I p I

be proportional to the non-DC potential voltage instead of being proportional to the Hall voltage, i.e.: uiH \\ 2 Κ- "ρΙ * Κ * ^. (3) 2 -1 eH i - i i * i --1 uJ = u

- ^ 2- P

Because of this when the situation is JeHJ ^ ju ^ | the absolute values of the output voltages should be subtracted from each other.

Theoretical and experimental studies have shown that for an isotropic Hall generator, e „and U are identical in both cases H p above and that the phase difference between them is either zero-la or 180 degrees (compare, for example, Wick RF: Solution for Electronic To the Hall field in a germanium gyrator, Journ Appl., Phys. nature causes the fact that when the pairs of opposite electrodes alternately change the phase between this Hall voltage and the non-DC potential, the phase differences change by 180 ° .If in the first position of these electrodes the voltage of this generator at any given moment is U1 = (EH "V siniJot (U) so respectively to position is u „= (E + U) sinoJ t (5)

d n p O

where E and U are the peak values of the Hall voltage and the non-DC potential H p voltage, respectively, and WQ is the control current angles aa j new.

If E,> U is the arithmetic mean of the magnitudes of these signs equal to-h p zero for the Hall voltage alone.

Thus, the effect of the non-DC potential voltage on this Hall voltage can be completely eliminated by separating the output signals of the two opposite electrode pairs of the generator by time.

In one embodiment, the device implementing the above method for eliminating the effect of this non-DC potential voltage from the Hall voltage includes 6,58840

The two pairs of opposite electrodes 2 and 3 and U and 5 of the Hall generator 1 (Fig. 2a), these are connected to the supply source 6 and the Hall voltage detector 7 via the switch 8.

This switch 8 is intended for connecting pairs of electrodes 2 and 3 and H and 5 from this Hall generator to the supply source 6 and in turn to the Hall residual detector 7 · This switch 8 can be any mobile or static switching device, being mechanical, electromechanical, electronic, etc. As an example, Figures 2b and 2c show two arrangements for the contacts of the electromechanical relay switch 8, which includes two pairs of transition contacts labeled I-1I and III-IV, each arranged so that the movable contacts 9 and 10 of the pairs I-II are connected to the supply source 6 and the movable contacts 11 and 12 of pairs III-IV are connected to a Hall voltage detector 7, each of the fixed, normally closed contacts 13, 1, 15 or 16 of each pair I-II and III-IV being connected to a corresponding fixed, normally open contact 17, 18, 19 or 20 in these same pairs and again in turn to one of the corresponding electro- 2, 3, U or 5 while the control coil 21 from the relay 8 is connected to the control generator 22.

An arrangement according to Figure 2b in which a normally closed contact 13 and a normally open fixed contact 17 of this override switch I are connected to a normally open contact 19 of override contacts III and normally closed contacts 1U and 18 of override contacts II are connected to normally open contact 20 over normally open contact 20 15 in the overshoot contact III provides the possibility of inverting the output signal from this Hall generator when the generator electrodes are exchanged therein.

The arrangement according to Fig. 2c, in which the fixed contacts 13, 17 and 1 and 18 of the overshoot contacts I and II are cross-connected to the fixed contacts 15, 19 and 16 and 20 of the overshoot contacts III and IV, respectively, does not invert the output voltage of this Hall generator when its electrodes change seats.

The device shown in this context works as follows:

When the Hall generator 1 receives a direct current I through one pair of opposite electrodes 2 and 3, which in the initial position of the switch 8 (cf. Fig. 2b) are connected via conductors 9, 13 and 10 and 1¼ to the supply source 6 and when subjected to constant magnetic induction and 5 across the second pair

Hall voltage eu and non-DC potential voltage U. Suppose now that these two H p voltages have the same polarity. The hall voltage detector 7 connected via the contacts 11 and 15 and 12 and 16 to the electrodes U and 5 in this generator 1 has a direct current measuring device and reads the value of the output voltage = e ^ + U ^.

When the contacts of the relay 8 are connected by means of the control signal U, each signal was obtained from the control generator 22, the electrodes k and 5 of the Hall generator 1 are connected via the T 58840 contacts 9 and 17 and 10 and 18 to the supply source 6 and the electrodes 2 and 3 to the Hall voltage detector 7 * generator 1 is the Hall voltage e

B

with respect to irreversible (non-reciprocal) and reversible with respect to non-DC potential is the output voltage generated in the generator across electrodes 2 and 3 now of magnitude U = -e + U. Since the contacts of the relay 8 (compare Fig. 2b) are connected 2 n p so that they invert the voltage, the Hall voltage indicator now indicates the output voltage U'2 = e ^ - U ^.

If the voltage U used by the control generator 22 varies by a certain period, the output voltage U £ will come from this generator 1, which is generated by both electro-; of the 2 and 3 and U and 5 pairs to have a waveform similar to that shown in Fig. 3. If inverted, the resulting output signal will have U £; a DC component proportional to the Hall voltage e and an AC voltage component proportional to the non-DC potential voltage U 1. If, on the other hand, the quantity is not inverted, the contact arrangement shown in Fig. 2c must be used. The resulting output signal of the generator 1 thus has an alternating component proportional to the Hall voltage e and a direct voltage component which n

is proportional to the non-DC potential voltage U. Depending now on these relay contacts; Depending on the arrangement used, the detector 7 should be either a DC voltage meter (when U2 is inverted) or an AC meter (when U2 is not inverted). j When the Hall generator 1 is energized using the alternating current I at a certain fixed period number from the supply source 6 (Fig. 2a), it follows from the above and also from equations U and 5> that the exchange of electrodes 2 and 3 and U and 5 an output voltage Ui of amplitude! modulated signal (Lake 3b), which can be expressed to make it necessary; and measured using an average meter 7 (the output signal in Figure 3b is the output signal of the amplitude detector). I

i Thus, the deviation of the Hall voltage indicator 7 by an angle in the above j cases is proportional to the average value of the magnitudes of the output marks, mit-; and occur across a pair of opposite electrodes, it wants to say the Hall voltage e ^ and is independent of the non-equipotential voltage U.

Thus, when comparing the present invention to previously known devices, the effects of the non-DC potential voltage on this Hall voltage can be completely eliminated, with the consequence that the time required for measurement or recording is decisively reduced, and further providing means for determining the absolute value of the magnetic induction in a given state, whereby the operations required for measuring or recording can be automated and the Hall generator can be successfully used in digital meters.

i

Claims (3)

58840 8. A method for eliminating the effects of a non-DC potential voltage at a Hall voltage, which method is based on the irreversible (non-reciprocal) operation of this Hall generator, characterized in that the Hall generator is supplied alternately with alternating current through one of two pairs of opposite electrodes , whereby the true magnitude of the Hall voltage can be estimated from the arithmetic mean of the magnitudes of the voltages present in at least two consecutive output signals. Apparatus for carrying out the method according to claim 1, wherein a pair (2 and 3) of opposite electrodes 1 of the Hall generator (1) is connected to the supply source (6) and another pair of opposite electrodes (U and 5) is connected to the Hall voltage detector (7) , characterized in that it comprises a switch (8) by means of which the pairs of opposite electrodes (2 and 3 and ä and 5) are alternately connected to the Hall voltage detector and alternately to the supply source. Device according to Claim 2, characterized in that the switch (8) for these Hall generator electrodes is of the electromechanical type, having at least two pairs (I-II and III-IV) of override contacts arranged so that the movable contacts (9 and 10) ) from the second pair (I-LI) or connected to the supply source (6) and the movable contacts ("M and 12") of the second pair (ilf-IV) are connected to the Hall voltage detector (7) of each fixed, normally closed contact (13,17, 1 ^ and 18) of the second pair (i-Il) being connected to the corresponding fixed, normally open contact (19, 16, 20 and 15) in the opposite pair (III-IV) and to one of the respective electrodes (2, 3, ^ and 5) here In the Hall generator (1) while the control circuit (21) of this switch (8) is connected to the control generator (22).