Патент USA US2409314код для вставки
4 Oct. 15,1946. _ J’, B, REEVES CURRENT REGULATOR Filed Feb. 5, 1945' L5 L4 _ 2,409,312 I ' _ 2 Sheets-Sheet l l . _ ' 16 L1 v 15, 1945- ‘ ‘J. B. REEVES I I 2,409,312‘ CURRENT REGULATOR Filed Feb; 5, 1945 LL a4 _ 725a 2 Sheets-Sheet 2 Patented Oct. 15, 1946 2,469,312 UNITED STATES PATENT OFFICE 2,409,312 I CURRENT REGULATOR James B. Reeves, White?sh Bay, Wls., assignor to ' Cutler-Hammer, Inc., Milwaukee, Wis., a cor notation of Delaware Application February 5, 1945, Serial No. 576,335 6 Claims. (01. 172-239) 1 . The invention relates to the current control of dynamo-electric machines or other translating circuits, and while not limited thereto, it is par ticularly applicable to the control of motors which are supplied with armature current from a varia ble voltage generator where it is desired to limit the current ?owing between the-generator and motor upon changes of the motor load or changes of the generator voltage. ~ > r - 2 ' _ ; electron tubes l4 and I5. The electron tube_ 14. is a duplex tube, having cathodes Ma and M“, anodes MC and W‘, respectively, and control elec trodes Me and [4‘, respectively. 5 The electron tube [5 is provided with a cathode. I55, an anode I5‘), and a control electrode l5°. The anodes Illc and W1 are jointly connected to__ a bus bar L1 which constitutes one terminal ‘of, a ‘ source of direct current of constant potential; An object of the invention is to provide im 10 the other terminal of said source being a bus bar', proved means> for automatically controlling the. L2. The cathode I53 is connected to the bus bar‘ armature current of a motor by controlling the L1, through a voltage divider l6, which is provided‘ ?eld excitation of a generator supplying said with an adjustable contact. The anodeltl‘? is‘ armature current. connected to the bus bar L1, through a resistorv Another object is to provide in a system of the l1, while the cathode I5a is connected to the bus aforementioned type for limiting through control of the generator excitation the maximum torque tof the motor upon changes of load thereon. Another object is to provide in a system of the aforementioned type for affording different limits of motor currents for different operating condi tions of the motor. 1 bar L2, through a resistor l8, which is preferably paralleled by a voltage regulating tube‘ l9. The grid [5° is connected to the two cathodes Ma and I4‘), and is also connected through a resistor 2!], to the bus bar L2. The grid Me is connected to. the terminal of the current shunt l2, which isv nearest to the generator, while they grid It1 is - Another object is to provide in a system of the aforementioned type for varying the excitation connected .to the terminal of the current shunt‘ l3, which is nearest to the motor H. The oath-p of the generator so as to maintain a constant odes Ill‘3L and Nb‘ are also connected to the nega motor current upon tendencies of such current tive terminal ofv a biasing battery 2l,.,which ‘is paralleled by a voltage divider 22, which is pro to increase. . ' Another object is to provide for controlling, in videdwith adjustable contacts 22a, 22b, 22fJ and a system of the aforementioned type, the accel erating current in response to the motor speed. 30 -. The field winding‘ ll)” of the generatorv is sup-' - Otherobjects and advantages will hereinafter plied with current from the lines‘ L3, L4 of an. 22d. appear.‘ _ ' - k ‘ 'I'hehaccompanying drawings are illustrative of an embodiment of the invention. . Figure '1 illustrates a system in which a sepa_-'_ 7 . . . alternating current source of‘ supply, through a transformer 23, which has a primary winding‘. 23"; and a centerjtapped secondary winding 23“. The secondary winding ‘is further provided with addi: rately excited reversible direct current motor is tional .taps oneach'side of the center tap inter mediate between the latter and the end terminals erator, while - . ~l of the winding 23”. Each end terminal. of the Fig. 2 illustrates a non-reversible system in Winding"23b is connected to one of the ‘anodes 24b cludingcertain modi?cations of the control of 40 and 25‘), respectively, of gaseous electron tubesj24 the generator ?eld. and 25, respectively, which tubes are also provided supplied with energy from a variable voltage gen Referring to Fig. l, the same illustrates a var with cathodes 24a and 25*‘, respectively, and 'con-. iable voltage generator l0, having an armature trol electrodes 24? and 25°, respectively. 'The' l0“, and a separately excited regulating ?eld tubes 24 and 25 are reversiblyvconnectable to the winding lllb. he generator supplies current to 45 ?eld winding lob, by a pair of‘ electromagnetic the armature Hat of a motor II which is also reversing switches 26 and 21, each provided with provided with a ?eld winding lib. The latter may be energized from any suitable direct current‘ source, the energizing current being adjusted to two normally open main contacts 26b and 26°, and 21b and 210, respectively, normally‘ open auxiliary, a suitable value. The armatures Illaand II“ are connected into a closed loop which includes cur rent shunts I 2 and I3 connected in serieswith each other and with the generator and the motor armature. . The control system comprises two high vacuum contacts 26d, 213‘, '26g and 21d, 21‘. and 21B, respec tively, normally closed auxiliary contacts 266 and‘ 21° respectively; and energizing windings 26*‘.and 21“, respectively. One terminal each of the con tacts 26b and 21b is jointly connected to one'ter-. minal of the Winding ID"; the other terminalof '_ which is connected to one terminal of. the contacts. 2,409,312 4 3 26° and 21°. The cathodes 24° and 25a are jointly connected to the second terminal of the contacts 26*’ and 21°. The center tap of the winding 23b 21K, 261 and 2'!I is connected to the sliding con tacts 22°, 22b, 22(1 and 221, respectively. To start the equipment, the lines L1, L2 and the lines L3 and L4, as well as the motor ?eld l U’, are is connected to the other terminal of contacts 26° and 2'!b and to one terminal of the primary wind in energized and the generator armature is rotated by its prime mover. The energization of the field ing 29a of a transformer 29 which also has a cen ter tapped secondary winding 29*’. The other terminal of the winding 29‘1 is connected to one intermediate terminal of the winding 2311 through winding I lb establishes the desired magnetic ?eld in the motor ll, while energization of the lines L3, L4 causes a potential to be impressed by the a condenser 30 and to the other intermediate 10 transformers 23 and 29 upon the anodes of the tubes 24 and 25. A potential is also impressed terminal of the said winding 23b through a varia upon the control electrodes 24° and 25°. By ad ble resistor 3|. The condenser 30, the resistor 3| justment of the resistor 3!, the phase relation and the winding 298L form a phase shifting net- > of the‘ potential impressed upon the anodes 24° work by means of which the phase. anglev of the voltage impressed upon the control electrodes of 15 and25b, with respect to the phase angle of the voltage impressed upon the control electrodes 24" tubes 24 and 25, in relation to the phase angle of and 25°, and thus. the maximum current passed the voltage of the lines L3 and L4, may be- varied. by tubes 24 and 25 to the winding lab, and thus The control electrodes 24° and 25°, respectively, the maximum voltage of the generator 10 may be are each connected to one of the end terminals of the secondary winding 29b of the transformer 2-0 adjusted. If it is now desired to operate the motor in a 29. The windings 25° and 21“ may be selectively en forward direction, the control lever 32° of the control switch 32 is moved to make contact with ergized from the line L3 and L4 through. a man the stationary contacts 32° and 32°, whereupon a ually operated pilot switch 32, which has a center bias lever 32° operable in one direction to make 25 circuit is established from line L3, over lever 32", contact 328, contacts 21°, through the energizing contact with stationary contacts 32b and 32d, and winding 26° to line L4, and the forward switch 26 operable in the opposite direction to make con is actuated. “ tact with stationary contacts 32° and 32°. Energization of the forward switch 25 com The pilot switch 32 is preferably so arranged pletes a circuit from line L3 over contact lever that, upon movement of the lever 32a to the re spective operating position... it closes circuit with 32“, contact 32°, contacts 26d, coil 34a, to line L4, contacts 32°, 32c prior to closure of circuit with and the relay 34 is actuated to close its contacts contacts 32b or 32°. The energizing winding 33a of an electromag 34b, 34(1 and 34f, thereby connecting the anode netic voltage responsive relay 33 is connected across the terminals of the motor armature l|°. The relay 33 is also provided with two normally open contacts 33b and 33°. One terminal of each of said contacts is connected to the line L3. 15b to the cathodes 24a and 25°, the movable contact of the voltage divider IE to the center tap of the transformer Winding 29". Closure of con» tacts 26b and 25° establishes a circuit from one end terminal of winding 2311, through tube 24, through contacts 26b, winding Nib, contacts 26°, The second terminal of the contact 33b is con 40 to the center tap of winding 23", and through said Winding back to tube 24, and alternately from the nected to the contact 32b while the second ter other end terminal of winding 23b, through tube minal of the contact 33° is connected to the con; tact 32°. One terminal each of the windings 26a 25, contacts 26”, winding lob, contacts 26°, to the center tap of the winding 23b. The generator and 21'1 is connectable to the line L4. The sec ?eld Illb is thus supplied with recti?ed direct cur ond terminal of the winding 26“ is connectable rent, and a voltage is induced in the generator through the normally closed contacts 21° to the armature Ilia to cause a current flow from said terminal 32°, while the second terminal of the armature through the shunts l2 and IS, the motor winding 21° is connectable through the normally armature I I3 back to the generator armature 10*‘. closed contact 26° to the terminal 32*’. An electromagnetic‘ relay 34 has an energizing 50 As the‘ current supplied to the motor armature l I" accelerates the latter, the terminal voltage of winding 34“, one terminal of which is connected the armature H“ increases until the voltage im to the line L‘, while the other terminal is'con pressed upon the energizing coil 33a is su?icient nected to one terminal each of the normally open to cause closure of the contacts 33b and 33°, Clo contacts 28“ and 21°. The other terminal of con sure of these contacts parallels the circuit between tact 26° is connected to contact 32° and the sec the contact arm 3-2 and the contact 32° so that ond terminal of contact 21° is connected tc‘con the lever 32° may be returned to the neutral posi tact 32°‘. The relay 34 has normally ‘open con tion to break circuit with the contact 32°, but tacts 34b, 34‘1 and 341, and normally closed contacts the switch 26 remains energized until the ener 34°, 34° and 34@. The contacts 34b are inter posed in a circuit between the cathodes 24a and 60 gization of the coil 33a is insufficient to maintain the contacts 33b and 33° closed. The circuit 25', and the anode IS”. The contacts 34° are which responds to the voltage drop in the shunts interposed in a circuit between the center tap of l2 and I3 is so adjusted that when no current the winding 29b and the anode IS”. The con ?ows between the generator and the motor both tacts 34° are interposed between the cathodes halves of the tube i4 conduct only a small cur 24' and 25“, and the movable contact of the volt rent. As the current supplied by the generator age divider IS; the contacts 34d are interposed increases, it produces potential differences in the between the center tap of the Winding 29b and shunts l2 and 13, which render the grid 14° less the movable contact of the voltage divider l6; positive and the grid l4f more positive with re one terminal of contacts 34t and 34K is connected spect to their respective cathodes, so that the po to the common terminal of the shunts l2 and I3; tential of the grid 14° is ultimately su?icient to the second terminal of contact 341 is'connected to stop current conduction in the left half of the one terminal of each of the contacts 26! and 218, tube l4, whereas the current ?owing through the while the second terminal of contact 348 is con right half of the tube I4 is increased. The rela nected to one terminal of each of the contacts 26f tion between the variation of the current in the and 21‘. The second terminal of contacts 26K, 2,409,312 6 tw'oihalves of the tube l4 and the potential of the is closed from said common terminal through grids W’ and I41 may be adjusted in a well known manner by adjustment of the supplemental grid bias afforded by the voltage divider 22. contacts 348 and 261, to contact 22d. Hence, the biasing potential for the tube 14 has been changed so that the system is regulated to afford a decel erating current which is higher or lower than the - This supplemental grid bias is equal to the volt age between the adjustable contact of the voltage divider 22, which is connected to the common terminal of the shunts l2 and i3, and the nega tive terminal of the battery 2 I. During operation of the motor in the forward direction, that is, While the switch 26 and the relay 34 are energized, accelerating current, depending upon the relative position of the contacts 22° and 22“. However, it is applied to the tubes 24 and 25 in the reverse direction from that during accel eration of the motor I I, thereby advancing the moment of ignition of the respective tube during the positive half cycle and tending to increase the current of the ?eld winding of the generator, a circuit is established from the common terminal of the shunts l2 and I3, through contacts 341, 25g’ and 22°, through part of the voltage divider 22, to decrease the dynamic braking effect. Thus, to the cathodes I42:‘ and Nb. Thus the adjust 15 the system maintains the braking current of the ment-of the contact 22° determines the supple motor at a constant value which may be sub-‘ mental grid biasing voltage and therefore the stantially the same as the accelerating current, relation between the current flowing in the gen so that the motor is brought to a standstill with erator-motor loop and the conduction of the two the maximum allowable torque and in'the' short halves of the tube 14, so that upon moving the 20 est possible time. When the‘motor speed ap contact 22° toward the positive terminal of the proaches zero, the voltage impressed upon the voltage divider 22, the current conducted by the coil 33“ is insuflicient to maintain the relay 33 tube I 4 for a given current in the motor-gen energized. Thus the contacts 33b and 33° are erator loop will be increased. ’ opened, which opens the maintaining circuit for As the conduction of the right half of the tube 25 the forward switch coil 26a and causes disconnec l4 increases, the potential of the grid |5° becomes tion of the generator ?eld Ii)b from the tubes '24 more positive, thereby increasing the conduction and 25, and the equipment returns to the initial of the tube 15 which increases the current in the condition. resistor H, which in turn reduces the positive po Operation of the motor in the opposite direc tential of the anode l5". The potential derived 30 tion is obvious from the foregoing. To start the from the voltage divider I6 is so adjusted that motor in reverse direction, the switch arm 32% is a desired potential di?erence exists between the moved to make circuit with the contacts 32d'and anode 15b and the movable contact of the voltage 32b, thereby energizing the reverse switch 21. The divider It. This potential difference is impressed functioning of the various elements of the system upon the grids 24° and 25°, as will be apparent upon reverse operation will be obvious from the from the diagram, and is superimposed upon foregoing description and the accompanying the potential impressed by the winding 29'’, the drawings. However, it is to be pointed out that polarity of the superimposed potential being such since during acceleration upon reverse operation, as to delay the moment of ignition of the tubes the contact 22b is connected to the common ter 24 and 25, during the respective conducting half a minal of the shunts l2 and I3, the position of cycle, so as to tend to decrease the current sup said contact determines the accelerating current plied to the generator ?eld I0", to a value which of the motor for reverse rotation. Upon reopen will result in a desired constant current ?owing in ing of the pilot switch 32 and during subsequent the generator-motor loop. As a result, the motor deceleration, the contact 22“ is connected to the is accelerated with‘a constant torque. Further ' common terminal of the shunts l2 and I3, so that more, after the motor has reached its maximum speed, the current cannot exceed the full load the position of the latter contact determines the decelerating current. Hence, during forward op value, such value being adjustable by adjust‘ eration, the positions of the contacts 22°and 22d determine the current in the mot0r~generator ment of the resistor 22. If it is now desired to stop the motor, the oper- q‘ loop during acceleration and deceleration, respec ator returns the lever 323 to the neutral position. As the voltage impressed on the coil 33“ is the tively, while for reverse operation the positions maximum terminal voltage of the motor, the relay 33 remains energized, thus maintaining the rent in the motor-generator loop during accelera switch 26 energized, which in turn maintains the connection between the recti?er tubes 24 and 25 and the generator ?eld winding 10b. However, opening the connection between the contact lever 32“, and the contact 32°, opens the circuit of the energizing coil 34*‘, so that the relay 34 opens crating currents for both directions of rotation and equal decelerating current for both directions or equal accelerating and decelerating currents of the contacts 22b and 22*’L determine the cur tion and deceleration, respectively. Obviously, the controller may be arranged to afford equal accel~ of one value for one direction and of another (ii the contacts 34b and 34“, thereby reversing the value for the other direction, or the currents may be adjusted for the same value under all condi connections between the anode l5h and the mov able contact of the voltage divider It on one hand, and the cathodes 24a and 25a and the center tap tions of operation. For certain of said condi tions, some of the commutating circuits for the of the winding 291), respectively. As now the action of the generator and motor is reversed, current‘ flows in the motor-generator loop in the reverse direction, so that now the left half of the tube l4 becomes conducting and the right half becomes non-conducting. During deceleration in the forward rotation of the motor, the contacts 34! are open and con tacts 3,4? are closed.‘ Therefore, the circuit be tween the contact 22° and the common terminal of the shunts l2 and I3 is opened, while a circuit biasing resistor 22-may be combined or omitted, as will be apparent. - Referring now to Fig. 2, the same illustrates a system in which the motor is required to operate only in one direction. However, in the system of Fig. 2, the accelerating current of the motor is controlled in accordance’ with the speed of the latter so ‘that the rate of acceleration and the motor current are'relatively low upon starting‘and: increase progressively as the motor attains speed. The'connections and the elements of the sys tem‘ are substantially the same as illustrated and 2,409,312 7 8 described in connection with Fig. 1, except ‘for the following: The electromagnetic reversing switch 21 has been omitted; the reverse speed armature for controlling maintenance of said connection of said electron tubes to said field winding independent of said manual means, and contacts 32b and 32d of pilot switch 32 have been means to render said electronic means responsive omitted; contacts 2B8, 25‘, 26g of switch 25, con tacts 33b of switch 33 and sliding contacts 22“, 22b of voltage divider 22 have been omitted. to the current circulating between said armatures to control and limit such current and including means for predetermining the limit. A voltage divider 50 has been added, one of its 2. In combination, a generator, having an ar mature and a ?eld winding, a pair of electron terminals being connected to the positive termi~ nal of the motor, while its other terminal is con~ nected to the common terminal of the shunts I2 and I3. The voltage divider 50 is provided with a movable contact 59a which is connected to one terminal of each of the contacts 341][ and 3%, while the connection of said contacts to the com mon terminal of the shunts I2 and I3 has been tubes, each having a control electrode, manual means for establishing connection of said tubes to said ?eld winding for supplying energizing cur rent to the latter, adjustable means including exciting current of the generator I0 is relatively opposite directions selectively, adjustable means electronic means for impressing a voltage on said control electrodes for regulating the current sup— plied by said tubes, a motor having an armature connected in circuit with said generator arma omitted. Furthermore, the movable contact 22‘1 ture, means responsive to the speed of said motor is directly connected to the second terminal of armature for controlling maintenance of said contact 348, while the movable contact 22° is di rectly connected to the second terminal of the 20 connection of said electron tubes to said ?eld winding independent of said manual means, and contact 34‘. The operation of the system is substantially the means to render said electronic means responsive to the magnitude and direction of current circu same as that illustrated in Fig. 1, except that the supplemental voltage existing between the mov lating between said armatures to control and limit such current and including means for predeter able contact Slla and the negative terminal of the voltage divider 50 is added to the bias supplied by mining different limits for different directions of said circulating current. the voltage divider 22 to the cathodes Me and I6“. Upon starting, the voltage of the generator ar 3. In combination, a generator, having an ar mature IIBL is substantially zero. Therefore, the mature and a ?eld winding, a pair of electron bias of the grids I48 and I4f with respect to the - tubes, each having a control electrode, reversing cathodes I4,1 and Nb, respectively, is a minimum. means including a pilot switch for establishing This as has been aforedescribed results in a high connection of said tubes to said ?eld winding impedance of the tubes 24 and 25, so that the for supplying energizing current to the latter in low and the motor I I accelerates with a relatively for impressing a voltage on said control elec low torque. As the motor starts to rotate, and its speed increases, the supplemental voltage sup~ plied by the voltage divider 50 progressively in creases, thereby reducing the positive bias of the grids Me and “If with respect to the cathodes IIIa and I41’, respectively, which in turn increases the trodes for regulating the current supplied by said current passed by the tubes 24 and 25, so as to cause an additional increase of the generator dependent of said pilot switch, and electronic means responsive to and controlling the current tubes, a motor having an armature connected in circuit with said generator armature, means re sponsive to the speed of 'said motor armature for controlling maintenance of said connection of said electron tubes to said ?eld winding in voltage to increase the torque and the accelera circulating between said armatures for impres ing a supplemental voltage on said control elec tion afforded by the motor II. Hence, at low speeds, the accelerating current and torque of the trodes to limit such current, said last named motor I I are relatively low, while at higher speeds means including means for predetermining the they are relatively high, the variation being ad limit. lustable by adjustment of the sliding contact 5%. ‘i. In combination, a generator, having an ar— This system is particularly suitable for large 5 I.) mature and a ?eld winding, a pair of electron centrifugal extractors which must be started at tubes, each having a control electrode, revers a very low rate in order to prevent undue unbal ing means including a pilot switch for establish ance of the rotating parts of the extractor. As ing connection of said tubes to said ?eld wind the extractor accelerates, the parts balance au ing for supplying energizing current to the lat tomatically and it is then permissible to increase . ter in opposite directions selectively, adjustable the rate of acceleration and the accelerating cur means for impressing a voltage on said control rent. The system shown in Fig. 2 may, of course, also be applied to reversible controllers, and it is fur electrodes for regulating the current supplied by thermore possible to provide for a high rate of ac celeration at low speed and a low rate of accel eration at high speed, the changes required for such operation being obvious. I claim: 1. In combination, a generator, having an ar mature and a field winding, a pair of electron tubes, each having a control electrode, manual means for establishing connection of said tubes to said ?eld winding for supplying energizing cur said tubes, a motor having an armature con nected in circuit with said generator armature. means responsive to the speed of said motor ar mature for controlling maintenance of said con nection of said electron tubes to said ?eld wind ing independent of said pilot switch, and elec tronic means responsive to and controlling the current circulating between said armatures for impressing a supplemental voltage on said con trol electrodes to limit such current, said last named means including means for-predetermin ing a plurality of limits, respectively, for differ~ rent to the latter, adjustable means including “' ent operating conditions. electronic means for impressing a voltage on said control electrodes for regulating the current sup plied by said tubes, a motor having an armature connected in circuit with said generator arma ture, means responsive to the speed of said motor 75 5. In combination, a- generator, having an ar mature and a ?eld winding, a pair of electron tubes, each having a control electrode, reversing means including a pilot switch for establishing connection of said tube to said ?eld winding for 2,409,312 9 , supplying energizing current to the latter in op posite directions selectively, adjustable means connection of said tubes to said ?eld winding for supplying energizing current to the latter in op posite directions selectively, adjustable means for impressing a voltage on said control elec trodes for regulating the current supplied by said tubes, a motor having an armature connected in. circuit with said generator armature, means re sponsive to the speed of said motor armature for controlling maintenance of said connection“ of said electron tubes to said ?eld winding inde-. ' for impressing a voltage on said control elec 0 trodes for regulating the currentsupplied by said tubes, 2. motor having an armature connected in circuit with said generator armature, means re sponsive to the speed of said motor armature for controlling maintenance of said connection of ' pendent of said pilot switch, electronic means 10 said electron tubes to said ?eld'winding inde for supplying a supplemental voltage varying in, pendent of said pilot switch, velectronic means for accordance with variations of the current circu supplying‘ a plurality of supplemental voltages lating between said armature's, means to Vary varying in accordance with variations of the cur the response of said electronic means to said cir- ' culating current, and electromagnetic means controlled by said reversing means and said speed responsive means, for impressing said supple mental voltage upon said control electrodes to limit such circulating current. rent circulating between said armatures, means to vary the response of said electronic means to said circulating current, and means including electromagnetic means responsive to said revers ing means and said speed responsive means for selectively impressing one of said supplemental 6. In combination, a generator, having an ar 20 voltages upon said control electrodes to limit such mature and a ?ield winding, a pair of electron circulating current to different values for differ tubes, each having a control electrode, reversing means including a pilot switch for establishing ent operating conditions. JAMES B. REEVES.