US3775702A - Transistor inverter circuit for supplying constant current output - Google Patents

Transistor inverter circuit for supplying constant current output Download PDF

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Publication number
US3775702A
US3775702A US00235335A US3775702DA US3775702A US 3775702 A US3775702 A US 3775702A US 00235335 A US00235335 A US 00235335A US 3775702D A US3775702D A US 3775702DA US 3775702 A US3775702 A US 3775702A
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United States
Prior art keywords
winding
output
load
feedback
constant current
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Expired - Lifetime
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US00235335A
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English (en)
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K Wallace
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ITT Inc
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North Electric Co
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Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M7/00—Conversion of AC power input into DC power output; Conversion of DC power input into AC power output
    • H02M7/42—Conversion of DC power input into AC power output without possibility of reversal
    • H02M7/44—Conversion of DC power input into AC power output without possibility of reversal by static converters
    • H02M7/48—Conversion of DC power input into AC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M7/53—Conversion of DC power input into AC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M7/537—Conversion of DC power input into AC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
    • H02M7/5383—Conversion of DC power input into AC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a self-oscillating arrangement
    • H02M7/53846—Control circuits
    • H02M7/53862—Control circuits using transistor type converters
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M3/00—Conversion of DC power input into DC power output
    • H02M3/22—Conversion of DC power input into DC power output with intermediate conversion into AC
    • H02M3/24—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters
    • H02M3/28—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC
    • H02M3/325—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal
    • H02M3/335—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
    • H02M3/338—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only in a self-oscillating arrangement
    • H02M3/3385—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only in a self-oscillating arrangement with automatic control of output voltage or current
    • H02M3/3387—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only in a self-oscillating arrangement with automatic control of output voltage or current in a push-pull configuration
    • H02M3/3388—Conversion of DC power input into DC power output with intermediate conversion into AC by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate AC using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only in a self-oscillating arrangement with automatic control of output voltage or current in a push-pull configuration of the parallel type
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M7/00—Conversion of AC power input into DC power output; Conversion of DC power input into AC power output
    • H02M7/42—Conversion of DC power input into AC power output without possibility of reversal
    • H02M7/44—Conversion of DC power input into AC power output without possibility of reversal by static converters
    • H02M7/48—Conversion of DC power input into AC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M7/53—Conversion of DC power input into AC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M7/537—Conversion of DC power input into AC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
    • H02M7/5383—Conversion of DC power input into AC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a self-oscillating arrangement
    • H02M7/53846—Control circuits
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
    • Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Definitions

  • ABSTRACT i A constant current power supply for providing constant current to loads having low power requirements and variable resistance characteristic in a reliable, less complex operating mode.
  • a tuned collector, resonant feedback, saturated current oscillator circuit is enabled to provide an alternating current output which is proportional to an adjustable DC control voltage, and, by proper selection of the feedback amplitude'in the oscillator circuit, the output current to a resistance load can be made independent of the load resistance.
  • the corona emitting device is a high voltage device and the value of the line capacity is therefore of a significant value.
  • the value of the capacity is a function of wiring devices and the like, the tolerance is quite high.
  • such arrangement comprises a transformer having a center-tapped primary winding, a center-tapped feedback winding and a secondarywinding.
  • first and second transistor have collector elements connected to opposite ends of the two sections of the primary winding in an oscillatory mode, the frequency of oscillation being determined by a tank circuit comprised of the magnetizing'inductance L, of the transformer, and a fixed capacitance C0v connected across the transformer primary or secondary winding.
  • the distributed capacity C in i the transformer windings and output wiring must also be considered along with the fixed capacitance C., thusly: v v
  • the output current of the transistors is, thus basically determined by the value of the control voltage, the baseto emitter drop of the transistor, the feedback voltage and the resistance'R in the emitter circuit of the transistors. Adjustment of the value of the control voltage E effects corresponding adjustment of the amplitude of the waveform output by the oscillator circuit, and thereby the value of l the constant current supplied to the load.
  • the transistor "collector output is comprised of a waveform having two sinusoidal components.
  • the first component which is determined by the control voltage is of a constant value which provides the normal load current requirements.
  • the second sinusoidal component of current is proportional to the output which appears across the secondary winding of the transformer, the amplitude of which component has been selected to compensate for the core loss resistance of the transformer.
  • Variation in the voltage across the secondary winding of the transformer is sensed by the center-tapped feedback winding which responsively adjusts the value of the feedback voltage e, to the base elements of the transistor to therebyadjust the value of the current output of the transistor pair, whereby the output current which flows over the load is maintained at a constant value.
  • FIG. 1 sets forth one embodiment of a constant current supply source of the invention
  • FIG. 2A sets forth selected waveforms which occur in the circuit of FIG. 1;
  • FIG. 28 sets forth, the equivalent circuit of the supply source shown in FIG. 1;
  • FIG. 3 is a modification of the basic circuit of FIG. 1 which provides a regulated DC output
  • FIG. 4 is a modification of the basic circuit of FIG. 1 which includes a feedback circuit which-derives a feedback control signal from the output circuit.
  • CIRCUIT DESCRIPTION bodiment comprised a corona-emitting device of the type commercially used in electrostatic copiers manufactured by Xerox Company, Rochester, New York,
  • saturable current oscillator 16 comprises a high voltage transformer 26 having a primary winding 20 which in one embodiment comprised 143 turns of No. '29 wire, a high voltage secondary winding 22 comprised of 35,385 turns of No. 39 wire, and a centertapped feedback winding 21 comprised of five turns of No. 29 wire.
  • Primary winding 20 has a center tap which is connected over input conductor 12 to the positive terminal of DC source 10.
  • the terminal ends of primary winding 20 are connected, respec- "tively, over conductors 28A, 19 to the collector elements of first and second power drive transistors 28, 30.
  • the emitters of transistors 28, 30 are in turn connected over a common resistor 31 (r to battery ground. Resistor 31 in the disclosed embodiment is in the order of ohms.
  • Transistors 28, 30 may comprise 2N3767 NPN transistors which are commercially available from Motorola Corporation, Phoenix, Ariz.
  • Filter capacitors 32, 33 may be connected across the upper and lower sections of winding to eliminate possible spurious oscillation of the transistors 28, 30.
  • Feedback winding 21 on high voltage transofrmer 26 has its terminal ends connected overconductors 27, 29 to the base elements of transistors 28, 30 respectively.
  • the centertap on feedback winding 21. is connected to the output of a control circuit 34 which supplies a constant voltage E over conductor l3to the center tap of the feedback winding 21.
  • Control circuit 34 which may be one of a'number of conventional adjustable constant voltage sources is shown in one embodiment as comprising a series-connected resistors 35 and Zener diode 36 which may be of the type available as a 1N4372A connected across the 45 volt output of DC source 10, and series-connected resistor 37 and diode 38 connected across diode 36.
  • the movable arm on adjustable resistor 37 is connected over conductor 13 to the junction of the center tap of the feedback winding 21 and also over capacitor 39 to ground. Capacitor 39 as thus connected operates to filter unwanted frequencies from the feedback winding.
  • Load 18 on high voltage transformer 26 is connected to load 18.
  • Load 18, as noted heretofore, may comprise a corona emitting device.
  • Capacitor 23 when connected across secondary winding 20 is in the order of 150
  • the value of capacitor 23 is in the order of luf.
  • the two vertical lines shown between the primary and secondary windings 20, 22 schematically represent the core of transformer 26.
  • the phase relationship between the primary winding 20 and feedback winding 21' are indicated by the dots in FIG. 1.
  • the feedback winding 21 provides positive feedback voltage over conductors 27, 29 to transistors 28 and 30 and causes the oscillator circuit 16 to oscillate at a frequency given by where C is the value of capacitor 23 when connected across secondarywinding 22 and L isthe magnetiZing inductance of transformer 26 referred to the secondary winding 22.
  • C also includes the capacitance value of thesecondary winding-22 of transformer 26 and the wire capacitance between conductors 24, 25.
  • the magnetizing inductance can be varied byadjusting the gap in the transformer core.
  • the value of capacitor 23 and/or the magnetic inductance L may be varied to obtain the desired operating frequency.
  • the magnitude of the collector current of the on transistor is approximately
  • the collector current or primary current is shown in FIG. 2A along with its relationship to the feedback voltage e,. -As shown, the primary current is made up of two components. One component is fixed by the setting of the control voltage E, provided by control voltage circuit 34, and the other of which component is proportional to the feedback voltage e, (which occurs across winding 21 which in turn is proportional to the voltage on the primary and secondary windings 20, 22 of transformer 26).
  • the effect of transistors 28 and 30 conducting current alternately through the biphase primary winding 20 is the current i,,, as shown in FIG. 2A which flows through N, turns (N, is the number of turns between the center tap and one side of winding 20).
  • the waveform for current i, in FIG. 2A is the summation of a square wave of amplitude E /R and a sinusoid of amplitude e,/R
  • the basic circuit of FIG. 1 which supplies constantcurrent at high voltage to an AC load may also be used to provide a DC constant current.
  • a rectifier circuit 40 (or multiplier) may be connected to the output of-the saturated current oscillator 16 to provide a constant current DC output.
  • a sensing unit 42 (current or voltage) is connected as shown in FIG. 4 to sense the output of the rectifier 40, and the sensed signal is fed as one input to a feedback amplifier 44.
  • a reference voltage E,- which may be adjustable is fed to a second input on the feedback amplifier 44, and the output of the feedback amplifier 44 is connected over conductor 13 to the center-tap of the feedback winding 21 in the saturated current oscillator 16in lieu of the signal from control circuit 34.
  • a constant current-supply circuit for providing constant current to aload having variable resistance characteristicscomprising input means for connecting said circuit to the first and second terminals of aDC power source, a first and second transistor, each of which has a collector, base and emitter element, transformer means having a center-tapped primary winding, a center-tapped feedback winding, an output winding, capacitor means connected across one of said transformer windings, means connecting the center tap of "said primary winding over said inputmeans to the first terminal of said source, means connecting the collector elements of said first and secondtransistors to said primary winding on opposite sides of said center tap, meansconnecting said base elements to-said feedback winding on opposite sides of said center'tap, common resistance means connecting the emitter elements of said first and second transistors common'tothe second for deriving an output for said load, said capacitor meansand the magnetizing inductance of said transformer means providing at least a part of a tank circuit for effecting operation of said transistors in an oscillatory mode, the circuit components including said common resistance
  • R comprises said common resistance means
  • N comprises the number of turns on said transformer output winding
  • N comprises the number of turns on said center-tapped primary winding
  • R comprises the equivalent core loss resistance of said transformer
  • N comprises the number of turns on said feedback winding.
  • control means includes sensor means for sensing a changing characteristic in said output for said load, and afeedback amplifier connected between said sensor means and said center tap on said feedback winding.
  • a constant current supply circuit as set forth in claim 6 in which said control means includes rectifier means connected between said output winding and said load, and said sensor means in said control means senses the DC output provided by said rectifier means to said load.
  • a constant current supply circuit for providing constant current to a load having variable resistance characteristics
  • input means for connecting said circuit to the first and second terminals of a DC a power source, a first and second transistor each having base, emitter and collector elements, means for driving said transistors in an oscillatory mode including transformer means having a center-tapped primary winding the opposite ends of which are connected to the collecvoltage control circuit, control means for connecting the constant voltage output from said control circuit to the center tap of said feedback winding, means connecting a feedback voltage to the base elements of said transistors whichis derived across said feedback winding, and means connecting a common resistance from said emitter elements of said transistors to said second terminal of said source, the circuit components including said common resistance, the number of turns on said transformer output winding, the number of turns on said center-tapped primary winding, and the number of turns on said feedback winding being of a value to provide a control voltage to the base elements of the transistors which has an amplitude which varies the level of oscillation of the signal output from said transistors by

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Dc-Dc Converters (AREA)
US00235335A 1972-03-16 1972-03-16 Transistor inverter circuit for supplying constant current output Expired - Lifetime US3775702A (en)

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US23533572A 1972-03-16 1972-03-16

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US (1) US3775702A (https=)
JP (1) JPS492041A (https=)
CA (1) CA976610A (https=)
DE (1) DE2311833A1 (https=)
GB (1) GB1414222A (https=)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4112393A (en) * 1975-03-20 1978-09-05 Patents Licensing International, Ltd. Automatically stabilized oscillator
US4339732A (en) * 1980-07-25 1982-07-13 Xerox Corporation Closed loop constant current tuned oscillator
FR2498131A1 (fr) * 1981-01-22 1982-07-23 Lecluse Jean Francois Dispositif d'alimentation des auxiliaires sur un vehicule a traction electrique
US4479259A (en) * 1980-11-03 1984-10-23 Siemens Aktiengesellschaft Transistor oscillator circuit
WO1985005508A1 (fr) * 1984-05-10 1985-12-05 Budapesti Müszaki Egyetem Circuit pour produire, transferer entre des circuits de tension differente et stabiliser un courant alternatif
US5214356A (en) * 1978-12-28 1993-05-25 Nilssen Ole K Dimmable fluorescent lamp ballast
GB2343065A (en) * 1998-10-01 2000-04-26 Tunewell Technology Ltd Improved power supply for series connected lamps
US20180033547A1 (en) * 2015-02-25 2018-02-01 Maschinenfabrik Reinhausen Gmbh Electric system with control winding and method of adjusting same

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2927837C2 (de) * 1979-07-10 1982-09-16 Peter 7750 Konstanz Kreutzer Transistorwechselrichterschaltung

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2919412A (en) * 1956-05-29 1959-12-29 Gen Electric Co Ltd Electric oscillator systems
US3284724A (en) * 1963-10-14 1966-11-08 Robertshaw Controls Co Oscillator with feedback bias amplitude stabilization
US3305760A (en) * 1963-01-16 1967-02-21 Larry L Davis Automatic line and battery operated power supply system
US3327199A (en) * 1963-08-23 1967-06-20 Westinghouse Electric Corp Transistorized high voltage regulated power supply system with temperature compensating means

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2919412A (en) * 1956-05-29 1959-12-29 Gen Electric Co Ltd Electric oscillator systems
US3305760A (en) * 1963-01-16 1967-02-21 Larry L Davis Automatic line and battery operated power supply system
US3327199A (en) * 1963-08-23 1967-06-20 Westinghouse Electric Corp Transistorized high voltage regulated power supply system with temperature compensating means
US3284724A (en) * 1963-10-14 1966-11-08 Robertshaw Controls Co Oscillator with feedback bias amplitude stabilization

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4112393A (en) * 1975-03-20 1978-09-05 Patents Licensing International, Ltd. Automatically stabilized oscillator
US5214356A (en) * 1978-12-28 1993-05-25 Nilssen Ole K Dimmable fluorescent lamp ballast
US4339732A (en) * 1980-07-25 1982-07-13 Xerox Corporation Closed loop constant current tuned oscillator
US4479259A (en) * 1980-11-03 1984-10-23 Siemens Aktiengesellschaft Transistor oscillator circuit
FR2498131A1 (fr) * 1981-01-22 1982-07-23 Lecluse Jean Francois Dispositif d'alimentation des auxiliaires sur un vehicule a traction electrique
WO1985005508A1 (fr) * 1984-05-10 1985-12-05 Budapesti Müszaki Egyetem Circuit pour produire, transferer entre des circuits de tension differente et stabiliser un courant alternatif
GB2343065A (en) * 1998-10-01 2000-04-26 Tunewell Technology Ltd Improved power supply for series connected lamps
US20180033547A1 (en) * 2015-02-25 2018-02-01 Maschinenfabrik Reinhausen Gmbh Electric system with control winding and method of adjusting same
US10186369B2 (en) * 2015-02-25 2019-01-22 Maschinenfabrik Reinhausen Gmbh Electric system with control winding and method of adjusting same

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Publication number Publication date
CA976610A (en) 1975-10-21
JPS492041A (https=) 1974-01-09
DE2311833A1 (de) 1973-09-27
GB1414222A (en) 1975-11-19

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Owner name: ITT CORPORATION 320 PARK AVE. NEW YORK, NEW YORK

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:NORTH ELECTRIC COMPANY;REEL/FRAME:004627/0492

Effective date: 19771013