US2027311A - Magnetic amplifier - Google Patents

Magnetic amplifier Download PDF

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US2027311A
US2027311A US676785A US67678533A US2027311A US 2027311 A US2027311 A US 2027311A US 676785 A US676785 A US 676785A US 67678533 A US67678533 A US 67678533A US 2027311 A US2027311 A US 2027311A
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winding
current
saturating
direct current
alternating current
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Gerald Alan S Fitz
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    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02B—HYDRAULIC ENGINEERING
    • E02B3/00—Engineering works in connection with control or use of streams, rivers, coasts, or other marine sites; Sealings or joints for engineering works in general
    • E02B3/02—Stream regulation, e.g. breaking up subaqueous rock, cleaning the beds of waterways, directing the water flow
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F9/00—Magnetic amplifiers
    • H03F9/02—Magnetic amplifiers current-controlled, i.e. the load current flowing in both directions through a main coil

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  • This invention relates to magnetic amplifiers and more particularly to electric relay and control systems which are characterized by the circumstance that the electrical effect to be detected, or to which the electric control function is required to be responsive, is of a low order of magnitude.
  • Very delicate relays or vacuum tubes while both of these types of apparatus can be furnished in effective and reliable form, are more widely used at the present time in connection with communication services where this type of apparatus receives specialized maintenance service and is installed in buildings specially provided therefor, in which special conditions are maintained, which are more favorable to apparatus of this kind than is the case in the generality of electrical and industrial plants.
  • My invention comprises novel and, effective methods of employing such reactors in multistage arrangements whereby cumulative amplification up to any'desired extent, according to the number of stages used, is rendered possible.
  • alternating current energy derived from a saturating reactor, and controllable by a direct current applied to the reactor is rectified and the resulting uni-directional current is applied to a further saturating reactor'so that the core of the second reactor is saturated with a direct current derived from the alternating current output of the first reactor.
  • the alternating current output of the second reactor may likewise be rectified and, in the same manner, applied to a third reactor. In this manner, a catenated system embodying any desired number of reactors may be provided.
  • Fig. 2 is a diagrammatic view of a. modification of the embodiment of my invention shown in Fig. l, and
  • Fig. 3 is a diagrammatic view of a further modification of my invention.
  • Fig. 1 I show a photo-electric cell i arranged to be afiected by a light effect (not shown) such as the intensity of daylight, or light from a source directed through a semiopaque medium such as smoke, liquid, etc., or any other type of photo-electric application.
  • Fig. l by way of example, a four-stage magnetic amplifier, in accordance with my invention, having input terminals 4 and output terminals 5.
  • my invention is not limited to any definite number of stages; fewer aoazsn may be used if they will sufiice for the required purpose. Any number of additional stages may be added, arranged and connected in a similar manner, whereby the energy level may be stepped up, without limit, to any extent required. 5
  • the photo-electric cell i is energized from a suitable direct current source 6, and the circuits of my magnetic amplifier may be energized through terminals 1 from a source of alternating current 8 which may, for example, be 10 110 volts, 60 cycles.
  • I may provide, as shown, a transformer 9 for energizing, at a different voltage, the various circuits of my magnetic amplifier.
  • the four-stage amplifier circuit shown in Fig. 1 includes four saturating 15 reactors I0, 20, 30, 40, each having magnetic cores ll, 2
  • I Associated with each saturating reactor, I provide rectlfiers I4, 24, 34, 44, which 20 may be of any suitable type, such as electrondischarge, vapor-electric, electrolytic, copper oxide, or other metallic contact type. I prefer to use a metallic contact rectifier of a type having good rectifying properties and low voltage 25 drop.
  • the photo-electric cell i energized from the source 6, is connected in series with the saturating winding i2 of the reactor 10.
  • the reactance winding l3 of the reactor Ill is energized with 30 alternating current in series with the rectifier Hi from the transformer 9.
  • a magnetizing current will be drawn by the reactor from the alternating current source, which magnetizing current will fiow in winding i3 and in the rectifier Hi.
  • photo-electric cur- 40 rent fiows in winding i2 whereby direct current saturation of the core Ill is set up, the current flowing in i3 and it will, in accordance with the magnitude of the photo-electric current, become augmented.
  • the saturating winding 22 of 45 the reactor 20 is energized with the rectified cur rent from the rectifier i4. Direct current saturation of the core ii of the reactor 20 will, therefore, be in accordance with the magnitude of the alternating current flowing in i3 and it.
  • the reactance winding 23 of the reactor 20 is likewise energized from the alternating current source in series with the rectifier 24 as are, in like manner, windings 33 and 43 and rectifiers 3d and id of the third and fourth stage reactors 55 30 and 30', respectively.
  • the saturating winding 32 of reactor 30 is energized with rectified current from 26 and, in like manner, the saturating winding 52 of the reactor 40 is energized from the rectifier 34. 60
  • the core i i of the first stage reactor i0 is saturated in accordance with the input to the amplifier which, in the pres ent case, is the current furnished by the photoelectric cell i.
  • the saturating winding 22 of the second stage reactor 20 receives direct current proportional to the alternating current flowing in the reactance winding of the first stage reactor ii].
  • the saturating winding 32 of the third stage receives direct current proportional to the alternating current drawn by the reactance winding 23 of the second stage reactor 20 and, in like manner, saturating winding 42 of the last stage reactor 40 receives direct current propor- 35 tional to the alternating current in the reactance winding 33 of the third stage reactor 30.
  • Rectifled current from the last stage rectifier 44 is connected to fiow in the operating coil of the contactor 2.
  • the contactor 2 therefore, is energized with direct current proportional in magnitude to the alternating current flowing in the reactance winding of the last stage reactor.
  • the saturating windings of the second, third and fourth reactors receive direct current proportional to the alternating current flowing in the reactance winding of each of the preceding stages.
  • I provide special compensating windings 25, 35, 45, situated on the reactors 20, 30, 40, respectively.
  • the compensating windings 25, 35, 45 are wound co-axially with the direct current saturating windings 22, 32, 42 and are energized with direct current in series with rheostats 26, 36, 46, by means of a rectifier ll energized from the transformer secondary 8.
  • the connections of the coils 25, 35, 45 are made so that the magnetizing effect, due to these coils, acts in opposition to the direct current magnetizing effect of the saturating coils 22, 32, 42.
  • the purpose of these coils is to compensate for the normal magnetizing current of the reactors.
  • the reactance windings i3, 23, 33, 43 will carry a magnetizing current when no direct current flows in the saturating windings i2, 22, 32, 42.
  • the effect of direct current in the saturating windings will be to increase the current flowing in the reactance windings.
  • the effect of the compensating windings 25, 35, 45 is to permit application to the reactor in each stage of a direct current saturating effect which shall be, not proportional to the current in the reactance winding of the preceding stage, but instead, proportional to the increase thereof due to the extent to which the preceding stage is saturated.
  • this effect is accomplished by adjusting the current in the compensating winding 25 by means of the rheostat 26 so that the direct current excitation set up by 25 is equal and in opposition to the ampere turns set up by the winding 22 due to the current flowing therein when no direct current is flowing in the first stage saturating winding l2.
  • the net direct current effect tending to saturate the core of 20 is zero.
  • the current in 32 is observed when no D. C. saturating effect is applied to in and the rheostat is adjusted for minimum value of the current in 32.
  • the effect of the compensating winding 25 is to cause the core of 20 to be saturated to an extent proportional to the difference between the current flowing in 22 when current flows in I2 and the lesser current which flows in 22 when the core of I0 is unsaturated, due to the absence of any current in i2.
  • an amplifled saturating effect is applied to 20 which is substantially proportional to the degree of saturation of ID.
  • the core of 20 would be partially saturated due to the magnetizing current in ill. This would cause a marked increase in the magnetizing current flowing in the winding 23.
  • the core of 30 will be saturated to a still further extent causing, in like manner, a still greater increase in the magnetizing current flowing in the winding 33.
  • the core of 40 would be even more strongly saturated than 30.
  • each of the successive stages is, nevertheless, subjected to an initial saturating effect, which is of increased extent in each succeeding stage, it is obvious that with more than a very limited number of stages, the cumulative effect of the magnetizing currents of the intermediate stages will result in complete initial saturation of the final stage under which condition the arrangement would be completely useless.
  • the effective gain given by the first stage may be expressed by dividing the watts dissipated in the saturating winding l2 due to a given photo-electric current, into the difference between the watts developed in the winding 22 due to said photo electric current and the watts in winding 22 when there is no current in 92.
  • the resistance of 22 should be suitably matched with the characteristics of the reactor l0 and its winding l3, which value of resistance may readily be determined by experiment.
  • the alternating current voltage derived from 9 should also be appropriately determined in relation to the permeability curve and characteristics of Ill. If the voltage of 9 be varied, it will be found that a fairly extended range of voltage exists within which approximately maximum gain can be obtained. Above and below this range, the gain decreases markedly.
  • a curve showing the relation between gain per stage and applied A. C. voltage would resemble, in general form, the permeability curve of the core material from which it is derived.
  • the core of I is saturated by photo-electric current to such an extent that the current in i3 is increased in a ratio of the general order of magnitude of two to one.
  • the compensating windings are a material feature of the invention. Not only is the gain per stage greatly increased thereby but, in addition, due to the compensation effect, there is no limit to the number of stages which may be employed.
  • the core of Hi may be arranged to be completely unsaturated with any specific value of photo-electric current corresponding to the predetermined condition of illumination. Any change from this condition will then cause saturation of i0 and actuation of the contactor 2.
  • each compensating winding may be supplied from indiil ildual reactors and rectifiers similar to H3 and ever, for general use.
  • the net output of the first stage- which, as explained previously, may be expressed as the watts developed in 22 due to the saturation of ill by the photo-electric current, minus the watts developed therein when i0 is unsaturated-will, due to the amplifying eifect of the saturating reactor ill, be many times the watts input into E2, the net D. C. ampere turns available to saturate 20 will likewise be substantially greater than the ampere turns applied to ill by the photo-electric current in i2.
  • the saturating effect produced in 20 will be much greater than the saturation produced in I!) by the current in i2, and the output of 20, represented in a similar manner by the difference watts developed in 32, will be yet again amplified.
  • the outputs of 30 and ll] will be of progressively increased amplitude.
  • Rectified output from the last stage is taken directly to the contactor 2. In this case, there will be some direct current in the coil of the contactor 2 when i0 is unsaturated due to the magnetizing current flowing in 53 under this condition.
  • the resulting saturating eifects set up in progressively amplified degrees in the several stages causes substantial saturation of Q0, and the current in the contactor coil will be increased substantially.
  • the confactor 2 may, therefore, be adjusted so that the normal current, due to the magnetizing current of to, is substantially less than the drop-out value.
  • the current in the coil may be caused to increase toa value substantially exceeding the pick-up value of 2 and the contactor is positively actuated t close its contacts. If the photo-electric efie ceases, the current will be reduced to below the drop-out value and the contactor will open the circuit.
  • the saturating reactors Ill, 20, 30, 40 are preferably of dissimilar type as shown in Fig. 1.
  • the design of these reactors for the several stages is influenced by the following considerations.
  • Saturating reactors such as are suitable for use in my magnetic amplifying system, usually consist of two interlinked magnetic systems, one carrying an alternating flux and the other car rying a direct flux, a common portion carrying both of these fluxes.
  • Such reactors are preferably constructed so that there is no inductive relation, through this common portion, between the A. C. and D. C. exciting windings.
  • the maximum output of a saturating reactor forany given frequency, will be a function of the cross-section of the alternating portion of the magnetic circuit and of the number of turns in inductive relation therewith. Thus, in practice, for reasons of winding space, the maximum output tends also to be related to the length of the alternating portion of the magnetic circuit.
  • maximum output reference is made to the maximum posrible difference which can be caused in the watts expended in a load circuit controlled by the reactor when the reactor is completely saturated, as compared with the condition when no D. C. saturation is applied.
  • the dimensions of the middle legs of the reactor 40 which is used for the output stage, can be determined in accordance with the rated output for which the amplifying system is to be designed.
  • the amount of D. C. power required to saturate the last stage will be substantially less than the output power. Accordingly, the dimensions of the alternating magnetic circuit constituted by the two center legs of the reactor in the penultimate stage may be similarly determined since this should be capable of an output equal to the power required to saturate the last stage, plus losses in rectification.
  • the reactors should be so proportioned that the alternating portions of the magnetic circuit can be raised to the saturation point with the minimum amount of direct current excitation. It is evident that the shorter be the length of the two center legs, the more readily will this part of the magnetic circuit be saturated.
  • the direct current excited portion of the magnetic circuit is preferably made large in comparison with the alternating portion. The greater the length of the magnetic circuit comprising the solid portion of the center leg, the outer legs, and the horizontal portions joining these, the larger will be the window area of the core punching and the greater will be the space available for the DC saturating winding. The greater the winding space, the greater will be the excitation in ampere turns which can be produced per micro-watt of input power.
  • the magnetic potential gradient around the magnetic circuit which includes both outer and inner legs may be made such that the constricted section. represented by the center legs constitutes very nearly the total magnetic reluctance of this magnetic path.
  • the magnetizing force, or ampere turns per unit length, applied to the two center legs will be equal to the saturating ampere turns divided by an effective length of magnetic path which will only very slightly exceed the length of the short center legs.
  • a reactor having core proportions similar to the first stage core ll, shown in Fig. 1 has satisfactory amplifying characteristics. If desired, all of the four reactors might be made, in increasing size, of similar proportions. However, I have shown in Fig. 1 all four reactors of like external dimensions. This gives somewhat reduced gain, per stage, in the latter stages, but is a convenient practical arrangement permitting standard size saturating coils for all stages, minimum tool expense in producing the core punchings, and a compact assembly.
  • Fig. 2 is a modification of my invention adapted to provide the above result.
  • Fig. 2 I show the last stage only of an amplifier, which may consist of a plurality of stages, and in all other respects may be as shown in Fig. l.
  • the last stage saturating reactor 50 has a saturating winding 52 and a reactance winding 53 similar to the arrangement shown in Fig. l.
  • the transformer 9 has a tap 56 which may desirably be adjustable and approximately in the neighborhood of the mid-point in the secondary winding.
  • I provide an additional reactor 55 having a. magnetic circuit closely corresponding to the portion of the reactor 50 which is traversed by alternating current magnetic flux.
  • the reactor 55 may have a core dimensioned to correspond with the two middle legs of 50 and may have a winding of the same number of turns as the winding 53.
  • the magnetizing current which would fiow in its winding would be precisely equal to the magnetizing current which would be drawn by the winding 53, if connected to the same A. C. voltage.
  • the reactors 50 and 55 are connected in series across the winding 9 so as to form a balanced bridge arrangement.
  • the final stage rectifier 55 is connected between the tap 56 on the transformer winding 9 and the junction between the reactors 50 and 55.
  • the tap on the transformer Q is adjusted so that the bridge is in balance when no net direct current saturating effect is applied to the reactor 50. Under this condition the potential of the junction will be substantially equal to that of the mid-point tap on the winding 9 and there will be substantially no alternating voltage applied to the rectifier 5 3.
  • the rectifier current from 5 3, which constitutes the output of the magnetic amplifier, I show in Fig. 2 connected to a power consuming device 5? which may be, for example, a motor.
  • the balanced bridge arrangement by means of which direct current is applied to the motor 51, with compensation for magnetizing current effect, may be utilized for inter-stage magnetizing current compensation in place of the compensating windings 25, 35 and 45 in Fig. 1, if desired.
  • Fig. 2 be supposed to represent an intermediate stage compensated in this way, 51 would represent the saturating winding, such as ,22, 32 or, in Fig. 1.
  • I may use, instead of a tap on the transformer 9, a bridge circuit comprising the reactors 50 and 55, and two variable resistors or impedances, energizing the bridge from the transformer 9 and connecting the rectifier .54 across equi-potential points of the bridge.
  • Fig. 1 a magnetic amplifying system adapted to be energized by photo-electric current from the photosensitive element I
  • my magnetic amplifying system may be used in conjunction with any kind of electrical input effect whatever of such order of smallness as may render such amplifying means necessary.
  • the input effect in Fig. 1 is represented by a direct current
  • the amplifier may be caused to actuate the contactor 2 in response to any alternating current input effect by providing an additional rectifier through which rectified current, derived from such an alternating current eifect, may be provided in the winding l2.
  • l2 may be energized with rectified current derived from a microphonic audio frequency effect whereby contactor 2 may be actuated in response to a tone signal.
  • my magnetic amplifier may be employed for amplifying alternating current effects provided the frequency of these effects be substantially less than the frequency of the source 8.
  • the amplifier may be energized from a source of super-audio frequency and the unidirectional current applied to the winding 12 may be modulated with audible frequency.
  • Fig. 3 I show two complete magnetic amplifiers 60 and 600, each of which may be substantially similar to the arrangement shown in Fig. 1, having input terminals 4, output terminals 5 and power supply terminals 3, all as shown in Fig. 1. Both these amplifiers are energized through terminals from a source of alternating power a which may be of a frequency substantially higher than the frequency of the effect which it is desired to amplify.
  • the alternating current effect to be amplified is applied to terminals 64.
  • the input connections of the two magnetic amplifiers 60 and son are energized in parallel, through oppositely connected rectifiers 6i and 62 from the input terminals 64.
  • the output terminals 5 of the amplifiers 60 and 600 are likewise connected in parallel, in opposite sense, to supply a load or output circuit 65.
  • the input windings 4 of 60 and 600 will be energized alternately in response to successive positive and negative half cycles of the input effect. Accordingly, the output delivered at terminals 5 by the amplifiers 60 and 600 will consist of alternate amplified intermittent uni-directional impulses corresponding to the half cycles applied to the input terminals 4.
  • the terminals 5 being connected in opposite sense to the load 65, these half cycles will be combined so as to supply amplified alternating current to the load 65.
  • a magnetic amplifier comprising a plurality of saturable core devices connected in cascade, each having a saturating winding and an output winding, a source of control current connected to the saturating winding of the first of said devices, means for energizing said output windings, a circuit including rectifying means interconnecting the output winding of each device with the saturating winding of the next successive device, a controlled circuit connected to the output winding of the last of said devices, and means for substantially eliminating the effect on the controlled circuit of the magnetizing current of any of said devices, but the last, when unsaturated, comprising means associated with each device after the first for neutralizing the saturation thereof due to the magnetizing current of the preceding device.
  • a magnetic amplifier comprising a plurality of saturable core devices connected in cascade, each having a saturating winding and an output winding, a source of control current connected to the saturating winding of the first of said devices, means for energizing said output windings, a circuit including rectifying means interconnecting the output winding of each device with the saturating winding of the next successive device, a controlled circuitconnected to the output winding of the last of said devices, and means for substantially eliminating the effect on the controlled circuit of the magnetizing current of any of said devices, but the last, when unsaturated, comprising a compensating saturating winding for each of said devices after the first and means for energizing said compensating windings with current of such value that the M. M. F. of each is equal and opposite to that due to the magnetizing current of the preceding device.
  • a magnetic amplifier comprising a plurality of saturable core devices connected in cascade, each having a saturating winding and an output winding, a source of control current connected to the saturating winding of the first of said devices, means for energizing said output windings, a circuit including rectifying means interconnecting the output winding of each device with the saturating winding of the next successive device, a controlled circuit connected to the output winding of the last of said devices, and means for substantially eliminating the effect on the controlled circuit of the magnetizing current of any of said devices, but the last, when unsaturated, comprising a compensating saturating winding for each of said devices after the first, further rectifying means for energizing said compensating windings with uni-directional currents, and means for adjusting the value of said currents so that the M. M. F. of each of said compensating windings is equal and opposite to that due to the magnetizing current of the preceding device.
  • a magnetic amplifier comprising a plurality of saturable core devices connected in cascade, each having a saturating winding and an output winding, a source of control current connected to the saturating winding of the first of said devices, means for energizing said output windings, a circuit including rectifying means interconnecting the output winding of each device with the saturating winding of the next successive device, a controlled circuit connected to the output winding of the last of said devices, and means for substantially eliminating the effect on the controlled circuit of the magnetizing current of any of said devices, but the last, when unsaturated, comprising means associated with each device after the first for neutralizing the saturation thereof due to the magnetizing current of the preceding device, at least one of said saturable core devices having a core made of a nickel alloy capable of being raised substantially to saturation point by a magnetizing force of less than one Gilbert per centimeter.
  • a magnetic amplifier comprising a plurality of saturable core devices connected in cascade, each having a saturating winding and an output winding, a source of control current connected to the saturating winding of the first of said devices, means for energizing said output windings, a circuit including rectifying means interconnecting the output winding of each device with the saturating winding of the next successive device, a controlled circuit connected to the output winding of the last of said devices, and means for substantially eliminating the effect on the controlled circuit of the magnetizing current of any of said devices, but the last, when unsaturated, comprising means associated with each device after the first for neutralizing the saturation thereof due to the magnetizing current of the preceding device, the saturable core devices in the several stages having cores so proportioned that the magnetic circuit which is traversed by alternating current magnetic fiux is of increased dimensions in successive stages.
  • a magnetic amplifier comprising a plurality of saturable core devices connected in cascade, each having a saturating winding and an output winding, a source of control current connected to the saturating winding of the first of said devices, means for energizing said output windings, a circuit including rectifying means interconnecting the output winding of each device with the saturating winding of the next successive device, a controlled circuit connected to the output winding of the last of said devices, and means for substantially eliminating the effect on the controlled circuit of the magnetizing current of any of said devices, but the last, when unsaturated, comprising means associated with each device after the first for neutralizing the saturation thereof due to the magnetizing current of the preceding device, at least one of the saturable core devices having a core so proportioned that the length of the magnetic circuit traversed by direct current flux is substantially greater than the length of the magnetic circuit which is traversed by the alternating current flux.
  • a magnetic amplifier comprising a plurality of saturable core devices connected in cascade, each having a saturating winding and an output winding, a source of control current connected to the saturating winding of the first of said devices, means for energizing said output windings, a circuit including rectifying means interconnecting the output winding of each device with the saturating winding of the next successive device, a controlled circuit connected to the output winding of the last of said devices, and means for substantially eliminating the effect on the controlled circuit of the magnetizing current of any of said devices, but the last, when unsaturated, comprising means associated with each device after the first for neutralizing the saturation thereof due to the magnetizing current of the of saturablecore devices connected in cascade,
  • each having a saturating winding and an output winding a source of control current connected to the saturating winding of the first ofsaid devices, means for energizing said output windings, a circuit including rectifying means interconnecting the output winding of each device with the saturating winding of the next successive device, a controlled circuit connected to the output winding of the last of said devices, and means for substantially eliminating the efiect on the controlled circuit of the magnetizing current of any of said devices, but the last, when unsaturated, comprising means associated with each device after the first for neutralizing the saturation thereof due to the magnetizing current of the preceding device, at least one of the saturable core devices having a core made of a nickel alloy capable of being raised substantially to saturation point by a magnetizing force of less than one Gilbert per centimeter, and at least one of the saturable core devices having a core made of steel.
  • a magnetic amplifier comprising a plurality of saturable core devices connected in cascade, each having a saturating winding and an output winding, a source of control current connected to the saturating winding of the first of said devices, means for energizing said output windings, a circuit including rectifying means interconnecting the output winding of each device with the saturating winding of the next successive device, a controlled circuit connected to the output winding of the last of said devices, and means for substantially eliminating the effect on the controlled circuit of the magnetizing current of any of said devices, when unsaturated, comprising means associated with each device after the first for neutralizing the saturation thereof due to the magnetizing current of the preceding device, said last mentioned means being characterized in that they do not involve inter-stage power losses and corresponding reduction in the efiective gain per stage.
  • a magnetic amplifier comprising a plurality of saturable core devices connected in cascade, each having a saturating winding and an output winding, a source of control current connected to the saturating winding of the first of said devices, means for energizing said output windings, a circuit including rectifying means interconnecting the output wnding of each device with the saturating winding of the next successive device, a controlled circuit connected to the output winding of the last of said devices, and means for substantially eliminating the effect on the controlled circuit of the magnetizing current of any of said devices, but the last, when unsaturated, comprising a compensating saturating winding for each of said devices after the first, together with means whereby, when, due to voltage variation, the magnetizing current of the preceding device is changed, the current in said compensating winding is commensurately changed.
  • a magnetic amplifier comprising a plurality of saturable core devices connected in cascade, each having a saturating winding and an output winding, 9. source of control current connected to the saturating winding of the first 10 of said devices, means for energizing said output windings, a circuit including rectifying means interconnecting the output winding of each device with the saturating winding of the next successive device, a controlled circuit connected to the output winding of the last of said devices, and means for substantially eliminating the effect on the controlled circuit of the magnetizing current of any of said devices, but the last, when unsaturated, comprising a compensating saturating winding for each of said devices after the first, rectifying means for energizing said compensating windings with current of such value that the M.
  • M. F. of each is equal and opposite to that due to the magnetizing current of the preceding device, a further saturable core device having magnetic characteristics related to those of the preceding device, and means for energizing said further rectifying means in accordance with the magnetizing current drawn by said last mentioned saturable core device whereby, when, due to its voltage variation, the magnetizing current of the preceding device is changed, the current in said compensating winding is commensurately changed.
  • a source of alternating current a first saturable core device having an alternating current winding, energized from said source, and a direct current saturating winding
  • means for supplying current to said direct current winding rectifying means effectively connected to said alternating current winding
  • a second saturable core device having an alternating current winding, energized from said source, and a direct current saturating winding
  • said direct current winding being energized from said rectifying means, a circuit energized in accordance with an electrical condition of said second mentioned alternating current winding, a second rectifier, energized from said alternating current source, and a further direct current winding energized from said second rectifier and connected to oppose the saturating effect of said second mentioned direct current saturating winding
  • said last named direct current winding being so proportioned that its M. M. F. is substantially equal to that due to the magnetizing current in the alternating current winding of said first mentioned saturable core device when no direct current ex
  • a source of alternating current a source of alternating current
  • a first saturable core device having an alternating current winding, energized from said source, and a direct current saturating winding
  • means for supplying current to said direct cur- 05 rent winding rectifying means effectively connected to said alternating current winding
  • a second saturable core device having an alternating current winding, energized from said source, and a.
  • direct current saturating winding said 70 direct current winding being energized from said rectifying means, a circuit energized in accordance with an electrical condition of said second mentioned alternating current winding, a further direct current winding co-axial with said 76 second mentioned direct current saturating winding, and means for supplying to said last mentioned winding a direct current of such value that the magnetic eifect thereof is in opposition and is substantially equal to the magnetic effect" of the rectified current which flows in said second mentioned direct current saturating winding when no direct current saturating effect is applied to said first mentioned saturable core device.
  • a source of alternating current a first saturable core device having an alternating current winding, energized from said source, and a direct current saturating winding, means for supplying current to said direct current winding, rectifying means effectively connected to said alternating current winding, 9.
  • second saturable core device having an alternating current winding, energized from said source, and a direct current saturating winding, said direct current winding being energized from said rectifying means, a circuit energized in accordance with an electrical condition of said second mentioned alternating current winding, a further direct current winding co-axial with said second mentioned direct current saturating winding, and means for supplying to said last mentioned winding a direct current of such value that the magnetic eifect thereof is in opposition and is substantially equal to the magnetic effect of the rectified current which fiows in said second mentioned direct current saturating winding when no direct current saturating effect is applied to said first mentioned saturable core device, at least one of said saturable core devices having a core made of a nickel alloy capable of being raised substantially to saturation point by a magnetizing force of less than one Gilbert per centimeter.
  • a source of alternating current a first saturable core device having an alternating current winding, energized from said source, and a direct current saturating winding, means for supplying current to said direct current winding, rectifying means effectively connected to said alternating current winding, 9.
  • second saturable core device having an alternating current winding, energized from said source, and a direct current saturating winding, said direct current winding being energized from said rectifier, a circuit energized in accordance with an electrical condition of said second mentioned alternating current winding, and a further direct current winding opposing the effect of said second mentioned direct current winding, and means for energizing said last mentioned winding, said last named direct current winding being so proportioned that its M. M. F.
  • At least one of the saturable core devices having a magnetic core so proportioned that the length of the magnetic path of the portion traversed by direct current fiux is substantially greater than the length of the magnetic circuit which is traversed by the alternating current fiux.
  • a source of alternating current a first saturable core device having an alternating current winding, energized from said source, and a direct current saturating winding
  • means for supplying current to said direct current winding rectifying means effectively connected to said alternating current winding
  • a second saturable core device having an alternating current winding, energized from said source, and a direct current saturating winding, said direct current winding being energized from said rectifying means, a circuit energized in accordance with an 5 electrical condition of said second mentioned alternating current winding, a further direct current winding opposing the effect of said second mentioned direct current winding, and means for energizing said last mentioned winding, said 10 last named direct current winding being so proportioned that its M.
  • M. F. is substantially equal to that due to the magnetizing current in the alternating current winding of said first mentioned saturable core device when no direct current excitation is applied thereto, at least one of the saturable core devices being so proportioned that the cross-section of the magnetic circuit traversed by the direct current flux is substantially greater than the cross-section of the magnetic circuit which is traversed by the alternating current flux.
  • a source of alternating current a first saturable core device having an alternating current winding, energized from said 25 source, and a direct current saturating winding, means for supplying current to said direct current winding, rectifying means effectively connected to said alternating current winding, a second saturable core device having an alternating 30 current winding, energized from said source, and a direct current saturating winding, said direct current winding being energized from said rectifying means, a circuit energized in accordance with an electrical condition of said second mentioned alternating current winding, a second rectifier energized from said alternating current source, and a further direct current winding energized from said second rectifier and connected to oppose the saturating eflfect of said second mentioned direct current saturating winding, said last named direct current winding being so proporiioned that it produces a substantially constant magnetomotive force equal to that due to a substantially constant saturating effect which 45 it is not desired should influence
  • an alternating current supply circuit a saturable core device having an alternating current winding and a direct current 50 saturating winding, means for supplying current to said direct current winding, means for energizing said alternating current winding from said supply circuit, an electro-magnetic device having a first direct current exciting winding and a second direct current exciting winding, rectifying means, means effectively connecting said rectifying means to said alternating current winding, means for energizing said first exciting winding with uni-directional current from said rectifying 60 means, means actuated in accordance with the magnetization of the core of said electro-magnetic device, a.
  • a source of alternating current a first saturable core device having an alternating current winding, energized from said source, and a direct current saturating winding, means for producing very small amounts of electrical energy not exceeding one hundred microwatts, means for supplying current from said means to said direct current winding, rectifying means efiectively connected to said alternating current winding, a second saturable core device having an alternating current winding, energized from said source, and a direct current saturating winding, said direct current winding being energized from said rectifying means, together with a circuit energized in accordance with an electrical condition of said second mentioned alternating current winding, at least one of said saturable core devices having a magnetic core made of nickel alloy capable of being raised substantially to saturation point by a magnetizing source of less than one Gilbert per centimeter.
  • a source of alternating current a first saturable core device having an alternating current winding, energized from said source, and a direct current saturating winding, means for producing very small amounts of electrical energy not exceeding one hundred microwatts, means for supplying current from said means to said direct current winding, rectifying means efiectively connected to said alternating current winding, a second saturable core device having an alternating current winding, energized from said source, and a direct current saturating winding, said direct current winding being energized from said rectifying means, together with a circut energized in accordance with an electrical condition of said second mentioned alternating current winding, at least one of said saturable core devices having a magnetic core made of nickel alloy capable of being raised substantially to saturation point by a magnetizing force of less than one Gilbert per centimeter, at least one of said saturable core devices having a magnetic core so proportioned that the length of the magnetic circuit traversed by direct current fi
  • an alternating current supply circuit a first saturable core device hav-' ing an alternating current winding and a direct current saturating winding, means for supplying current to said direct current winding, rectifying means, a core having magnetic characteristics similar to those of a portion of said first saturable 1 core device, a winding on said core, a bridge circuit including said winding and the alternating current winding of said first saturable core device, means for energizing said bridge circuit from said alternating current supply circuit across one diagonal, means for energizing said rectifying means from another diagonal of said bridge,
  • a second saturable core device having an alternating current winding and a direct current saturating winding, means for energizing said second alternating current winding from said supply circuit, means for energizing said second mentioned direct current saturating winding from said rectifying means, an output circuit and means for energizing said output circuit in accordance with an electrical condition of said last mentioned alternating current winding, whereby said second saturable core device is caused to re- 5 ceive saturating excitation proportional to the diiierence between the alternating current fiowing in said first-mentioned saturable core device when said first mentioned device is subjected to a. direct current saturating effect and the alter- 10 nating current flowing therein when no direct current saturating effect is applied thereto.
  • an alternating current supply circuit a first saturable core device having an alternating current winding and a direct 15 current saturating winding, means for supplying current to said direct current winding, rectifying means, a core having magnetic characteristics similar to those of a portion of said first saturable core device, a winding on said core, a bridge cir- 20 cuit including said winding and the alternatingcurrent winding of said first saturable core device, means for energizing said bridge circuit from said alternating current supply circuit across one diagonal, means for energizing said 25 rectifying means from another diagonal of said bridge, means for causing said bridge to be balanced when no direct current excitation is applied to said first saturable core device, a second: saturable core device having an alternating curac rent winding and a.
  • an alternating current sup ply circuit a first saturable core device having an alternating current winding and a direct current saturating winding, means for supplying 55 current to said direct current winding, rectifying means, a core having magnetic characteristics similar to those of a portion of said first saturable core device, a winding on said core, a bridge circuit including said winding and the alternating 60 current winding of said first saturable core device, means for energizing said bridge circuit from said alternating current supply circuit across one diagonal, means for energizing said rectifying means from another diagonal of said bridge, 65 means for causing said bridge to be balanced when no direct current excitation is applied to said first saturable core device, a second saturable core device having an alternating current winding and a direct current saturating winding, 70 means for energizing said second alternating current winding from said supply circuit, means for energizing said second mentioned direct current saturating winding from said rectif
  • said second saturable core device is caused to receive saturating excitation proportional to the difference between the alternating current flowing in said first mentioned saturable core device when said first mentioned device is subjected to a direct current saturating effect and the alternating current flowing therein when no direct current saturating effect is applied thereto, at least one of the saturable core devices having a magnetic core so proportioned that the length of the magnetic circuit of .the portion traversed by direct current flux is substantially greater than the length of the magnetic circuit which is traversed by the alternating current flux.
  • an alternating current supply circuit a first saturable core device having an alternating current winding and a direct current saturating winding, means for supplying current to said direct current winding, rectifying means, a core having magnetic characteristics similar to those of a portion of said first saturable core device, a winding on said core, a bridge circuit including said winding and the alternating current winding of said first saturable core device, means for energizing said bridge circuit from said alternating current supply circuit across one diagonal, means for energizing said rectifying means from another diagonal of said bridge, means for causing said bridge to be balanced when no direct current excitation is applied to said first saturable core device, a second saturable core device having an alternating current winding and a direct current saturating winding, means for energizing said second alternating current winding from said supply circuit, means for energizing said second mentioned direct current saturating winding from said rectifying means, an output circuit, and means
  • an alternating current supply circuit a first saturable core device having an alternating current winding and a direct current saturating winding, means for supplying current to said direct currentwinding, rectifying means, a core having magnetic characteristics similar to those of a portion of said first saturable core device, a winding on said core, a bridge circuit including said winding and the alternating current winding of said first saturable core device, means for energizing said bridge circuit from said alternating current supply circuit across one diagonal, means for energizing said rectifying means from another diagonal of said bridge, means for causing said bridge to be balanced when no direct current excitation is applied to said first saturable core device, a second saturable core device having an alternating current winding and a direct current saturating winding, means for energizing said second alternating current winding from said supply circuit, means for energizing said second mentioned direct current saturating winding from said rec- 5 1 tifying means, an alternating current supply circuit
  • an alternating current supply circuit a saturable core device having an alternating current winding and a direct current 25 saturating winding, means for supplying current to said direct current winding, rectifying means,
  • a core having magnetic characteristics similar to those of a portion of said saturable core device, a winding on said core, a bridge circuit including 30 said winding and the alternating current winding of said saturable core device, means for energizing said bridge circuit from said alternating current supply circuit across one diagonal, means for energizing said rectifying means from another 35 diagonal of said bridge, means for causing said bridge to be balanced when no direct current excitation is applied to said saturable core device, an electromagnetic device having a direct current exciting winding, means for energizing said 40 exciting winding with uni-directional current from said rectifying means, means actuated in accordance with the magnetization of the core of said electro-magnetic device, whereby said electro-magnetic device is caused to receive exci- 45 tation proportional to the difference between the alternating current flowing in said saturable core device when said saturable core device is subjected to a direct current saturating effect and the alternating current flowing therein when no 50 direct current
  • a magnetic amplifying system comprising an alternating current input circuit, an alternating current supply circuit for supplying power of a frequency higher than that of said input, a 56 magnetic amplifier comprising a plurality of sat urable core devices, connected in cascade, each havinga saturating winding and an output winding, means for energizing said output windings from said supply circuit, a circuit including rec- 60 tifying means interconnecting the output winding of each device with the saturating winding of the next successive device, means connecting said input circuit to energize a saturating winding of said magnetic amplifier with uni-directional 65 current fluctuating in accordance with the frequency with said input, an output rectifier connected to rectify the output of said magnetic amplifier, a work circuit, and means including said output rectifier for supplying said work circuit with amplified energy of the frequency of said input and related thereto in magnitude.
  • a magnetic amplifying system comprising, an alternating current input circuit, an alternating current supply circuit for supplying power of a frequency higher than that of said input, a magnetic amplifier comprising a plurality of saturable core devices connected in cascade, each having a saturating winding and an output winding, means for energizing said output windings from said supply circuit, a circuit including rectifying means interconnecting the output winding of each device with the saturating winding of the next successive device, and means for substantially eliminating the effect on the last of said saturable core devices of the magnetizing current of any other of said devices, when unsaturated, comprising means associated with each device after the first for neutralizing the saturation thereof due to the magnetizing current of the preceding device, means connecting said input circuit to energize a saturating winding of said magnetic amplifier with uni-directional current fluctuating in accordance with the frequency of said input, an output rectifier connected to rectify the output of said magnetic amplifier, a work circuit, and means including said output rectifier for a
  • a push-pull alternating current magnetic amplifying system comprising, an alternating current input circuit, an alternating current supply circuit for supplying power of a frequency higher than that of said input, a pair of magnetic amplifiers, each of said amplifiers comprising a plurality of saturable core devices, connected in cascade, each having a saturating winding and an output winding, means for energizing said output windings from said supply circuit, a circuit including rectifying means interconnecting the output winding of each device with the saturating winding of the next successive de vice, a pair of input rectifiers connected in opposite sense and energized by said alternating current input, means for energizing a saturating winding of each of said magnetic amplifiers with unidirectional current from each of said last mentioned input rectifiers, whereby each of said amplifiers is subjected to a saturating effect alternately in accordance with successive input half cycles, a pair of output rectifiers connected to rectify the outputs of said magnetic amplifiers, a work
  • a push-pull alternating current magnetic amplifying system comprising, an alternating 10 current input circuit, an altematlng current supply circuit for supplying power of a frequency higher than that of said input, a pair of magnetic amplifiers, each of said amplifiers comprising a plurality of saturable core devices, con- 15 nected in cascade, having a saturating winding and an output winding, means for energizing said output windings from said supply circuit, a circuit including rectifying means inter-connecting the output winding of each device with the saturating winding of the next successive device, and means for substantially eliminating the effect on the last of said saturable core devices of the magnetizing current of any other of said devices, when unsaturated, comprising means asso- 2'5 ciated with each device after the first for neutralizing the saturation thereof due to the magnetizing current of-the preceding device, a'pair of input rectifiers connected in opposite sense and energized by said alternating current input, 80 means for energizing

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  • General Engineering & Computer Science (AREA)
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  • Ocean & Marine Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Civil Engineering (AREA)
  • Environmental & Geological Engineering (AREA)
  • Power Engineering (AREA)
  • Control Of Electrical Variables (AREA)
  • Amplifiers (AREA)
  • Revetment (AREA)
  • Investigating And Analyzing Materials By Characteristic Methods (AREA)
  • Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
US676785A 1932-07-01 1933-06-21 Magnetic amplifier Expired - Lifetime US2027311A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB18782/33A GB404034A (en) 1932-07-01 1932-07-01 Electric control and amplifying systems

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US2027311A true US2027311A (en) 1936-01-07

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GB (2) GB404034A (fr)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2464551A (en) * 1941-06-09 1949-03-15 Alimanna Svenska Elek Ska Akti Automatic regulator using transductors
US2588155A (en) * 1941-07-11 1952-03-04 Asea Ab Rectifier connection
US2677800A (en) * 1950-10-04 1954-05-04 Bill Jack Scient Instr Company Electrical control device
US2685680A (en) * 1947-11-19 1954-08-03 Automatic Telephone & Elect Magnetic vehicle detector
US2710313A (en) * 1948-10-12 1955-06-07 Vickers Inc Electromagnetic audio amplifiers
US2758161A (en) * 1952-12-05 1956-08-07 Gen Electric High gain self-saturating magnetic amplifier
US2768345A (en) * 1950-03-01 1956-10-23 Gen Electric Magnetic amplifier circuit
US2777021A (en) * 1954-06-04 1957-01-08 Westinghouse Electric Corp Parallel connected magnetic amplifier
US2853693A (en) * 1950-12-28 1958-09-23 Rca Corp Switching devices
US2932787A (en) * 1956-03-19 1960-04-12 Allis Chalmers Mfg Co Magnetic amplifier
US2980847A (en) * 1957-08-12 1961-04-18 Westinghouse Electric Corp Switching apparatus for magnetic amplifiers
US3511810A (en) * 1961-08-07 1970-05-12 Phillips Petroleum Co Dyed modified acrylonitrile and methacrylonitrile polymers

Families Citing this family (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE975102C (de) * 1937-01-02 1961-08-10 Aeg Anordnung zur Steuerung von Wechselstroemen mit Hilfe einer gleichstromvormagnetisierten Drosselspule
DE758289C (de) * 1938-08-19 1953-03-02 Siemens App Richtungsempfindlicher Magnetverstaerker
DE975928C (de) * 1939-01-24 1962-12-13 Siemens Ag Einrichtung zur Steuerung des Stromdurchganges durch Trockengleichrichter
DE740300C (de) * 1939-02-13 1943-10-18 Stalturbine G M B H Magnetischer Kaskadenverstaerker
DE975253C (de) * 1939-05-06 1961-10-19 Siemens Ag Transformatorkern
DE948177C (de) * 1940-10-26 1956-08-30 Aeg Hochueberlastbares Gleichspannungsrelais
DE970823C (de) * 1941-03-29 1958-10-30 Siemens Ag Magnetverstaerker
DE756138C (de) * 1941-04-08 1953-05-04 Siemens & Halske A G Anordnung zur Einstellung des im ungesteuerten Zustand die Drosseln durchfliessendenArbeitsstromes von magnetischen Verstaerkern
DE902633C (de) * 1941-07-25 1954-01-25 Siemens Ag Magnetischer Verstaerker
DE969296C (de) * 1942-08-20 1958-05-22 Siemens Ag Anordnung zur Aufrechterhaltung der Steuerwirkung von magnetischen Verstaerkern bei kleinen Verbraucherstroemen
NL67758C (nl) * 1943-08-14 1951-05-15 Philips Nv Regeneratief teruggekoppelde magnetische versterker met een zelfinductiespoel met een ferromagnetische kern
US2560284A (en) * 1945-10-26 1951-07-10 Automatic Elect Lab Voltage regulating system
DE896955C (de) * 1950-03-15 1953-11-16 Lorenz C Ag Schaltanordnung zur Gleichrichtung von Wechselspannungen
DE919831C (de) * 1950-06-15 1954-11-04 Siemens Ag Regeleinrichtung fuer Buehnenbeleuchtungsstromkreise
DE916201C (de) * 1951-04-27 1954-08-05 Siemens Ag Anordnung zum Schweissen mit Gleichstrom
DE970583C (de) * 1951-08-10 1958-10-09 Oskar Vierling Dr Schaltungsanordnung zum wahlweisen Schalten von Wechselstromkreisen in Fernmeldeanlagen
DE1097529B (de) * 1953-07-03 1961-01-19 Paul Brueckner Dr Ing Anordnung zum Regeln bzw. Steuern mit Magnetverstaerkern
DE1092129B (de) * 1957-05-14 1960-11-03 Antonin Polacek Kompensiertes Transduktorrelais
DE1258498B (de) * 1958-08-25 1968-01-11 Ibm Spannungsgeregelte Gleichrichteranordnung
DE1125488B (de) * 1959-10-12 1962-03-15 Siemens Ag Vollstaendig geschlossener dreischenkliger, aus Blechen ohne Stossfuge aufgebauter Mantelkern oder Ringkern fuer Magnetverstaerker mit besonders kleiner Eingangsleistung

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2464551A (en) * 1941-06-09 1949-03-15 Alimanna Svenska Elek Ska Akti Automatic regulator using transductors
US2588155A (en) * 1941-07-11 1952-03-04 Asea Ab Rectifier connection
US2685680A (en) * 1947-11-19 1954-08-03 Automatic Telephone & Elect Magnetic vehicle detector
US2710313A (en) * 1948-10-12 1955-06-07 Vickers Inc Electromagnetic audio amplifiers
US2768345A (en) * 1950-03-01 1956-10-23 Gen Electric Magnetic amplifier circuit
US2677800A (en) * 1950-10-04 1954-05-04 Bill Jack Scient Instr Company Electrical control device
US2853693A (en) * 1950-12-28 1958-09-23 Rca Corp Switching devices
US2758161A (en) * 1952-12-05 1956-08-07 Gen Electric High gain self-saturating magnetic amplifier
US2777021A (en) * 1954-06-04 1957-01-08 Westinghouse Electric Corp Parallel connected magnetic amplifier
US2932787A (en) * 1956-03-19 1960-04-12 Allis Chalmers Mfg Co Magnetic amplifier
US2980847A (en) * 1957-08-12 1961-04-18 Westinghouse Electric Corp Switching apparatus for magnetic amplifiers
US3511810A (en) * 1961-08-07 1970-05-12 Phillips Petroleum Co Dyed modified acrylonitrile and methacrylonitrile polymers

Also Published As

Publication number Publication date
DE650553C (de) 1937-09-27
FR766593A (fr) 1934-06-30
GB404034A (en) 1934-01-01
GB404039A (en) 1934-01-11

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