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Arrangement for the controllable supply of an electric lamp

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US3845350A
US3845350A US34792573A US3845350A US 3845350 A US3845350 A US 3845350A US 34792573 A US34792573 A US 34792573A US 3845350 A US3845350 A US 3845350A
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Prior art keywords
element
control
coupling
circuit
lamp
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Expired - Lifetime
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M Luursema
P Bolhuis
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Philips Corp
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Philips Corp
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    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05BELECTRIC HEATING; ELECTRIC LIGHTING NOT OTHERWISE PROVIDED FOR
    • H05B41/00Circuit arrangements or apparatus for igniting or operating discharge lamps
    • H05B41/14Circuit arrangements
    • H05B41/36Controlling
    • H05B41/38Controlling the intensity of light
    • H05B41/39Controlling the intensity of light continuously
    • H05B41/392Controlling the intensity of light continuously using semiconductor devices, e.g. thyristor
    • H05B41/3921Controlling the intensity of light continuously using semiconductor devices, e.g. thyristor with possibility of light intensity variations
    • H05B41/3924Controlling the intensity of light continuously using semiconductor devices, e.g. thyristor with possibility of light intensity variations by phase control, e.g. using a triac
    • GPHYSICS
    • G05CONTROLLING; REGULATING
    • G05FSYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES
    • G05F1/00Automatic systems in which deviations of an electric quantity from one or more predetermined values are detected at the output of the system and fed back to a device within the system to restore the detected quantity to its predetermined value or values, i.e. retroactive systems
    • G05F1/10Regulating voltage or current
    • G05F1/12Regulating voltage or current wherein the variable actually regulated by the final control device is ac
    • G05F1/40Regulating voltage or current wherein the variable actually regulated by the final control device is ac using discharge tubes or semiconductor devices as final control devices
    • G05F1/44Regulating voltage or current wherein the variable actually regulated by the final control device is ac using discharge tubes or semiconductor devices as final control devices semiconductor devices only
    • G05F1/45Regulating voltage or current wherein the variable actually regulated by the final control device is ac using discharge tubes or semiconductor devices as final control devices semiconductor devices only being controlled rectifiers in series with the load
    • G05F1/455Regulating voltage or current wherein the variable actually regulated by the final control device is ac using discharge tubes or semiconductor devices as final control devices semiconductor devices only being controlled rectifiers in series with the load with phase control
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02MAPPARATUS 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
    • H02M1/00Details of apparatus for conversion
    • H02M1/08Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters
    • H02M1/088Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters for the simultaneous control of series or parallel connected semiconductor devices
    • H02M1/092Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters for the simultaneous control of series or parallel connected semiconductor devices the control signals being transmitted optically
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02MAPPARATUS 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
    • H02M5/00Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases
    • H02M5/02Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc
    • H02M5/04Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters
    • H02M5/22Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M5/25Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a thyratron or thyristor type requiring extinguishing means
    • H02M5/257Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a thyratron or thyristor type requiring extinguishing means using semiconductor devices only
    • H02M5/2573Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a thyratron or thyristor type requiring extinguishing means using semiconductor devices only with control circuit

Abstract

The invention relates to an arrangement for the controllable supply of a lamp which to this end is arranged in series with a controlled semiconductor switching element. According to the invention the control circuit of the semiconductor switching element is equipped with an optoelectronic coupling element. In case of a defect in the control circuit this element prevents the lamp supply voltage from causing damage in this control circuit. In addition the invention provides the possibility of extinguishing the lamp in a simple manner, substantially without a light flash.

Description

United States Patent [191 Luursema et al.

1 1 ARRANGEMENT FOR THE CONTROLLABLE SUPPLY OF AN ELECTRIC LAMP [75] Inventors: Meerten Luursema; Pieter Jan Bolhuis, both of Emmasingel, Netherlands [73] Assignee: U.S. Philips Corporation, New

York, N.Y.

[22] Filed: Apr. 4, 1973 [21] Appl. No.: 347,925

[30] Foreign Application Priority Data Apr. 20, 1972 Netherlands 1. 7205293 [52] U.S. Cl.-' 315/291, 307/311, 315/297,

[51] Int. Cl. H05b 41/36 [58] Field of Search 315/291-297,

[56] References Cited UNITED STATES PATENTS 3,524,986 8/1970 Harnden 307/311 Gilbreath 315/291 Shuey 307/311 Primary ExaminerAlfred L. Brody Attorney, Agent, or Firm-Frank R. Trifari [57] ABSTRACT The invention relates to an arrangement for the controllable supply of a lamp which to this end is arranged in series with a controlled semiconductor switching element.

7 Claims, 1 Drawing Figure PHASE SHIFT NETWORK PAIENIEBnmea m4,

PHASE SHIFT AMPLIFIERS NETWORK ARRANGEMENT FOR THE CONTROLLABLE SUPPLY OF AN ELECTRIC LAMP The invention relates to an arrangement for controlling the supply of an electric energy to an electric lamp in which the lamp is arranged in series with a controlled semiconductor switching element across two input terminals of the arrangement. A control electrode of the controlled semiconductor switching element is connected to a control circuit, said control circuit incorpoating a potential-separating coupling element between a first part of the control circuit which is connected to the control electrode of the semiconductor switching element and another part of the control circuit, the first part of the control circuit being connected to an auxiliary voltage source.

A known arrangement of the kind mentioned above is described, for example, in U.S. Pat. No. 3,351,810. The coupling element in this known arrangement is a transformer whose primary winding is connected to a network for obtaining a variable phase shift. A drawback of this known arrangement is that in the event of a defect between the coupling element and the semiconductor switching element, the occurrence of a relatively high lamp supply voltage across a secondary winding of the transformer might generate, through the primary winding, a voltage across the phase-shifting network which exceeds the voltage for which this network is designed. I

An object of the invention is to obviate or at least mitigate the said drawback. According to the invention an arrangement for controlling the supply of electric energy to an electric lamp includes a controlled semiconductor switching element arranged in series with the lamp across two input terminals of the arrangement and in which a control electrode of the controlled semiconductor switching element is connected to a control circuit. The control circuit incorporates a potentialseparating coupling element between a first part of the control circuit which is connected to the control electrode of the semiconductor switching element and another part of the control circuit, and whereby the first part of the control circuit is connected to an auxiliary voltage source. The invention is characterized in that the coupling element is an opto-electronic coupling element which is arranged in such a manner that it is free from the influence of the light from the electric lamp.

An advantage of an arrangement according to the invention is that the relatively high lamp supply voltage cannot be transferred to the input side of the coupling element, even for dimmers where this supply voltage is present on that side of the coupling element which faces the control electrode of the controlled semiconductor switching element. As a result, in the event of a defect between the coupling element and the controlled semiconductor switching element, control circuit parts on the other side of the coupling element, such as a phase shifting network of a further control circuit likewise connected to this network, also are not damaged.

The prevention of such damage is related to the fact that a transfer can take place in the coupling element of an arrangement according to the invention in one direction only, namely from the light-transmitting part to the photosensitive part.

The light-transmitting part is formed, for example, by an auxiliary incandescent lamp.

In an arrangement according to the invention the light-transmitting part of the opto-electronic coupling element is preferably a light-emitting diode and the photosensitive part of this coupling element is a photosensitive transistor.

An advantage of this preferred embodiment is that the coupling element may be a very compact and cheap structural unit.

It is to be noted that opto-electronic coupling elements are known per se.

The electric lamp of an arrangement according to the invention is, for example, one incandescent lamp. An arrangement according to the invention may alternatively feed, for example, more than one lamp.

In a further preferred embodiment of an arrangement according to the invention, in which the lamp is an inductively stabilized discharge lamp and in which a first switch is present in series with the lamp and with the controlled semiconductor switching element, the control circuit includes a second switch for extinguishing the light from the light-transmitting part of the coupling element.

An advantage of this preferred embodiment is that the arrangement may also be switched off without this being accompanied by a bright lighting up of the lamp. The procedure to accomplish this end is firstly to operate the second switch so that the light-transmitting part of the coupling element is rendered inactive and hence also the control of the semiconductor switching element, and to subsequently open the first switch in series with the lamp.

In a proposed embodiment in which the coupling elemerit is a transformer and in which likewise the first of the two said switches is present, a switching off of this transformer by a subsequent switch (present in the control circuit) results in an instantaneous variation of the control of the controlled switching element such that a troublesome light flash of the lamp often occurs.

When using a transformer coupling element other more complicated methods have to be'used, for example, all control electrodes have to be switched off first before switching off the voltage supply.

A first opening of the first switch in series with the lamp is not to be recommended because then the current from a possible cos d) -capacitor may maintain the relevant semiconductor open for some time so that a light flash would also be produced.

The invention will be further described with reference to the accompanying drawing which shows an electrical circuit diagram of an arrangement according to. the invention.

Input terminals 1 and 2 are intended to be connected to an alternating voltage supply of 220 Volt, 50 Hz. Reference numeral 3 is a two-terminal switch. The terminals beyond the switch 3 are denoted by 4 and 5. A series arrangement of a low-pressure mercury vapour discharge lamp 6 of, for example, 40 Watts, a stabilizing coil (ballast) 7 and two anti-parallel arranged thyristors 8, 9 are connected to the terminals 4, 5. Furthermore a cos b -capacitor 10 for improvement of the power factor and a filament current transformer 11 are connected to the terminals 4, 5. Two secondary windings l2, 13 of the transformer 11 serve to supply the preheatable electrodes of the lamp 6.

Finally, a variable phase-shifting network 14, not shown in detail, is connected to the terminals 4, 5. A resistor B5 is connected to an output terminal of this network 14. The other side of the resistor is connected by two oppositely arranged diodes l6 and 17 to another output terminal of the network 14. A switch 18 (second switch) shunts the diodes l6 and 17.

The diode 16 forms part of an opto-electronic coupling element 19 the photosensitive part of which is a transistor. Likewise the diode 17 forms part of a similar opto-electronic coupling element 20. The terminals of an auxiliary direct voltage source are denoted by 21, and 22 is an amplifier. Conductors of the amplifier 22 lead to the control electrode and to the cathode of the thyristor 8.

Similarly, 23 denotes the terminals of an auxiliary direct voltage source and 24 denotes an amplifier. The amplifier 24 is similarly connected to conductors which lead to the control electrode and the cathode of the thyristor 9.

in the normal situation the lamp 6 is energized when the switch 3 is switched on. The brightness of the lamp 6 is then determined by the phase-shifting network which 14 passes control signals through the optoelectronic coupling elements 19 and to the thyristors 8 and 9..

A defect in a control part between one of the coupling elements (19 or 20) and the relevant thyristors (8, 9) cannot be transferred to the input part of the coupling elements. Thus it is avoided that other parts of the control circuit might be damaged.

When switching off the arrangement the switch 18 is closed first so that the coupling elements 19, 20 are rendered inactive. Subsequently the switch 3 is opened. This process leads to an extinction of the lamp 6 without the accompaniment of a bright flash of light from the lamp.

What is claimed is:

l. A circuit for controlling the supply of electric energy to an electric discharge lamp comprising, a pair of input terminals adapted to be connected to a source of electric energy, a controlled semiconductor switching element, a first switch, means connecting the discharge lamp and the first switch in series with the controlled semiconductor switching element across said pair of input terminals, a control circuit for the switching element, means connecting a control electrode of the controlled semiconductor switching element to said control circuit, said control circuit including a potentialseparating coupling element coupled between a first part of the control circuit which is connected to the control electrode of the semiconductor switching element and another part of the control circuit, means connecting the first part of the control circuit to an auxiliary voltage source, and said coupling element comprises an opto-electronic coupling element including a light-transmitting member and a photosensitive member which is arranged in such a manner that it is free from the influence of the light from the electric lamp, and said control circuit further includes a second switch for selectively extinguishing the light from the light-transmitting member of the opto-electronic coupling element.

2. A circuit as claimed in claim 1, characterized in that the light-transmitting member of the optoelectronic coupling element comprises a light-emitting diode and that the photosensitive member of said coupling element comprises a photosensitive transistor.

3. A system for controlling an electric discharge lamp comprising, a pair of input terminals adapted to be connected to a source of AC voltage, a controlled semiconductor switching element, means connecting the discharge lamp in series with the controlled switching element across said input terminals, a control circuit including a first part having an auxiliary source of voltage connected to a control electrode of the switching element for controlling the current flow therein, said control circuit further comprising an opto-electronic coupling element coupling the first part of the control circuit to a second part of the control circuit that includes means for producing a control signal for operating the opto-electronic coupling element and for controlling the controlled switching element via the first part of the control circuit, said opto-electronic coupling element being disposed so as to be unaffected by the light from said discharge lamp.

4. A system as claimed in claim 3 wherein .said optoelectronic coupling element comprises first and second light emitting diodes connected in anti-parallel to a source of voltage and first and second photosensitive transistors optically coupled to said first and second light emitting diodes, respectively.

5. A system as claimed in claim 3 wherein the control signal producing means of the second part of said control circuit includes a variable phase shift network with input terminals connected to the AC input terminals of the control system for deriving a control signal that varies as a function of the AC supply voltage at said AC input terminals.

6. A system as claimed in claim 5 further comprising a current stabilizing reactance element connected in series with the lamp and the switching element across the system AC input terminals.

7. A system as claimed in claim 3 further comprising a switching device for selectively deactivating the optoelectronic coupling element prior to deenergization of the discharge lamp.

i i k

Claims (7)

1. A circuit for controlling the supply of electric energy to an electric discharge lamp comprising, a pair of input terminals adapted to be connected to a source of electric energy, a controlled semiconductor switching element, a first switch, means connecting the discharge lamp and the first switch in series with the controlled semiconductor switching element across said pair of input terminals, a control circuit for the switching element, means connecting a control electrode of the controlled semiconductor switching element to said control circuit, said control circuit including a potential-separating coupling element coupled between a first part of the control circuit which is connected to the control electrode of the semiconductor switching element and another part of the control circuit, means connecting the first part of the control circuit to an auxiliary voltage source, and said coupling element comprises an opto-electronic coupling element including a light-transmitting member and a photosensitive member which is arranged in such a manner that it is free from the influence of the light from the electric lamp, and said control circuit further includes a second switch for selectively extinguishing the light from the light-transmitting member of the opto-electronic coupling element.
2. A circuit as claimed in claim 1, characterized in that the light-transmitting member of the opto-electronic coupling element comprises a light-emitting diode and that the photosensitive member of said coupling element comprises a photosensitive transistor.
3. A system for controlling an electric discharge lamp comprising, a pair of input terminals adapted to be connected to a source of AC voltage, a controlled semiconductor switching element, means connecting the discharge lamp in series with the controlled switching element across said input terminals, a control circuit including a first part having an auxiliary source of voltage connected to a control electrode of the switching element for controlling the current flow therein, said control circuit further comprising an opto-electronic coupling element coupling the first part of the control circuit to a second part of the control circuit that indudes means for producing a control signal for operating the opto-electronic coupling element and for controlling the controlled switching element via the first part of the control circuit, said opto-electronic coupling element being disposed so as to be unaffected by the light from said discharge lamp.
4. A system as claimed in claim 3 wherein said opto-electronic coupling element comprises first and second light emitting diodes connected in anti-parallel to a source of voltage and first and second photosensitive transistors optically coupled to said first and second light emitting diodes, respectively.
5. A system as claimed in claim 3 wherein the control signal producing means of the second part of said control circuit includes a variable phase shift network with input terminals connected to the AC input terminals of the control system for deriving a control signal that varies as a function of the AC supply voltage at said AC input terminals.
6. A system as claimed in claim 5 further comprising a current stabilizing reactance element connected in series with the lamp and the switching element across the system AC input terminals.
7. A system as claimed in claim 3 further comprising a switching device for selectively deactivating the opto-electronic coupling element prior to deenergization of the discharge lamp.
US3845350A 1972-04-20 1973-04-04 Arrangement for the controllable supply of an electric lamp Expired - Lifetime US3845350A (en)

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NL7205293A NL7205293A (en) 1972-04-20 1972-04-20

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US (1) US3845350A (en)
JP (1) JPS4917070A (en)
BE (1) BE798428A (en)
DE (1) DE2318444A1 (en)
ES (1) ES413892A1 (en)
FR (1) FR2180963B3 (en)
NL (1) NL7205293A (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2432256A1 (en) * 1978-07-24 1980-02-22 Esquire Inc dimmer circuit optocoupler for discharge lamp in a gas, high intensity
US4287455A (en) * 1979-12-18 1981-09-01 Erin Engineering (Ontario) Ltd. Power saving circuit for gaseous discharge lamps
EP0083992A1 (en) * 1982-01-11 1983-07-20 Cornell-Dubilier Electronics Inc. Circuit and method for controlling the output illumination of one or more gas discharge lamps
US4628230A (en) * 1985-08-05 1986-12-09 Mole-Richardson Company Regulated light dimmer control
EP0212892A1 (en) * 1985-08-09 1987-03-04 Parker Graphics Limited An electrical control circuit for controlling a variable AC load
US5469028A (en) * 1978-03-20 1995-11-21 Nilssen; Ole K. Electronic ballast drawing sinusoidal line current

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2425165B1 (en) * 1978-05-03 1981-12-04 Renault automatic adjustment circuit "cos ph" of a power variation of phase shifter Machine
GB2062372B (en) * 1979-10-20 1984-05-10 Plessey Co Ltd Thyristor control circuits
FR2527398A1 (en) * 1982-05-18 1983-11-25 Gen Electric Remote operated dimming circuit for fluorescent lamps - uses trigger pulse operated switching stage to regulate lengths of power pulses
JPH0317193B2 (en) * 1982-10-27 1991-03-07 Olympus Optical Co
DE3524266A1 (en) * 1985-07-06 1987-01-08 Philips Patentverwaltung Circuit arrangement for operating high-pressure gas discharge lamps

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3524986A (en) * 1967-02-06 1970-08-18 Gen Electric Semiconductor light gating of light activated semiconductor power control circuits
US3733528A (en) * 1971-08-02 1973-05-15 Hunt Electronics Co Dimmer unit for a lighting control system
US3766409A (en) * 1971-08-04 1973-10-16 Westinghouse Electric Corp Ac power control apparatus with improved switch driver means

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3524986A (en) * 1967-02-06 1970-08-18 Gen Electric Semiconductor light gating of light activated semiconductor power control circuits
US3733528A (en) * 1971-08-02 1973-05-15 Hunt Electronics Co Dimmer unit for a lighting control system
US3766409A (en) * 1971-08-04 1973-10-16 Westinghouse Electric Corp Ac power control apparatus with improved switch driver means

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5469028A (en) * 1978-03-20 1995-11-21 Nilssen; Ole K. Electronic ballast drawing sinusoidal line current
US4197485A (en) * 1978-07-24 1980-04-08 Esquire, Inc. Optocoupler dimmer circuit for high intensity, gaseous discharge lamp
FR2432256A1 (en) * 1978-07-24 1980-02-22 Esquire Inc dimmer circuit optocoupler for discharge lamp in a gas, high intensity
US4287455A (en) * 1979-12-18 1981-09-01 Erin Engineering (Ontario) Ltd. Power saving circuit for gaseous discharge lamps
EP0083992A1 (en) * 1982-01-11 1983-07-20 Cornell-Dubilier Electronics Inc. Circuit and method for controlling the output illumination of one or more gas discharge lamps
US4628230A (en) * 1985-08-05 1986-12-09 Mole-Richardson Company Regulated light dimmer control
EP0212892A1 (en) * 1985-08-09 1987-03-04 Parker Graphics Limited An electrical control circuit for controlling a variable AC load

Also Published As

Publication number Publication date Type
BE798428A (en) 1973-10-18 grant
NL7205293A (en) 1973-10-23 application
ES413892A1 (en) 1976-01-16 application
FR2180963B3 (en) 1976-04-09 grant
JPS4917070A (en) 1974-02-15 application
FR2180963A1 (en) 1973-11-30 application
DE2318444A1 (en) 1973-10-31 application
BE798428A1 (en) grant

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