Claims
- 1. An arrangement for ballasting a gas discharge lamp, comprising:
- a power line providing a substantially sinusoidal AC power line voltage at a pair of power line conductors; the power line conductors being electrically connected with earth ground;
- a rectifier arrangement connected with the power line conductors and operative: (i) to draw therefrom a line current having a substantially sinusoidal waveform, a substantially sinusoidal waveform being defined as a waveform having not more than 10% total harmonic distortion; and (ii) to provide a first DC voltage across a first pair of DC terminals; and
- a circuit arrangement connected with the DC terminals and functional to provide a high-frequency ballast output voltage between a pair of ballast output terminals; the ballast output terminals being operable to connect with a gas discharge lamp; the high-frequency ballast output voltage being of magnitude sufficient to ignite such a gas discharge lamp and to supply it with a high-frequency lamp current having crest-factor not higher than about 1.7; the circuit arrangement being characterized by including an inverter circuit powered from a second pair of DC terminals across which exists a second DC voltage having an absolute magnitude approximately equal to the peak absolute magnitude of the AC line voltage.
- 2. The arrangement of claim 1 wherein:
- (a) the second DC voltage has: (i) an instantaneous magnitude; and (ii) an average magnitude defined as having been averaged over a duration equal to that of a complete cycle of the AC power line voltage; and
- (b) the instantaneous magnitude does not deviate more than plus/minus 10% from the average magnitude.
- 3. The arrangement of claim 1 wherein the circuit arrangement is further characterized by including an auxiliary DC source connected in circuit with the ballast output terminals and operative to supply DC power to the second pair of DC terminals.
- 4. The arrangement of claim 3 wherein: (i) the auxiliary DC source has a pair of auxiliary DC terminals across which exists an auxiliary DC voltage; and (ii) the instantaneous absolute magnitude of the auxiliary DC voltage is approximately equal to the difference between the peak absolute magnitude of the AC power line voltage and the instantaneous absolute magnitude of the AC power line voltage.
- 5. The arrangement of claim 1 wherein a potentially shock-hazardous voltage exists between one'of the ballast output terminals and earth ground; the potentially shock-hazardous voltage being of magnitude insufficient to ignite said gas discharge lamp; thereby providing for a situation characterized as follows:
- (i) if a person were to connect with one of the ballast output terminals, while at the same time being electrically connected with earth ground, he would be subject to a hazardous electric shock; while
- (ii) if that same person were to connect with one of the ballast output terminals by way of said gas discharge lamp, even if he were to be electrically connected with earth ground, he would not be subject to a hazardous electric shock.
- 6. The arrangement of claim 1 wherein: (i) the instantaneous absolute magnitude of the first DC voltage is substantially equal to that of the AC power line voltages.
- 7. The arrangement of claim 1 wherein: (1) the second DC voltage is of substantially constant magnitude; and (ii) the high-frequency lamp current is characterized by being amplitude-modulated at a frequency twice that of the AC power line voltage.
- 8. An arrangement for ballasting a gas discharge lamp, comprising:
- a power line providing a substantially sinusoidal AC power line voltage at a pair of power line conductors; the power line conductors being electrically connected with earth ground;
- a rectifier arrangement connected with the power line conductors and operative: (i) to draw therefrom a line current; and (ii) to provide a first DC voltage across a first pair of DC terminals; the instantaneous absolute magnitude of the first DC voltage being approximately equal to that of the AC power line voltage; and
- a circuit arrangement connected with the DC terminals and functional to provide a high-frequency ballast output voltage between a pair of ballast output terminals; the ballast output terminals being operable to connect with a gas discharge lamp; the high-frequency ballast output voltage being of magnitude sufficient to ignite such a gas discharge lamp and to supply it with high-frequency lamp current; the circuit arrangement being characterized by including:
- (i) an inverter circuit provided with DC power from a second pair of DC terminals across which exists a second DC voltage having an absolute magnitude about equal to the peak absolute magnitude of the AC power line voltage; and
- (ii) an auxiliary DC source providing DC power from a pair of auxiliary DC terminals across which exists an auxiliary DC voltage having an absolute instantaneous magnitude equal to the difference between the absolute instantaneous magnitude of the second DC voltage and the absolute instantaneous magnitude of the first DC voltage; the pair of auxiliary DC terminals being connected with the first and the second pair of DC terminals.
- 9. The arrangement of claim 8 wherein part of the DC power provided to the inverter circuit is provided by the auxiliary DC source.
- 10. The arrangement of claim 9 wherein the auxiliary DC source is connected in circuit with the ballast output terminals and is operative: (i) to draw high-frequency power therefrom; and (ii) to convert this high-frequency power to DC power, at least part of which is provided to the inverter circuit.
- 11. An arrangement for ballasting a gas discharge lamp, comprising:
- a power line providing a substantially sinusoidal AC power line voltage at a pair of power line conductors; the power line conductors being electrically connected with earth ground;
- a rectifier arrangement connected with the power line conductors and operative: (i) to draw from the power line conductors a line current having a waveform composed of a substantially sinusoidal wave of frequency equal to that of the AC power line voltage, to which is added, at least under certain circumstances, relatively narrow pulses of alternating polarity and with frequency equal to that of the AC power line voltage; and (ii) to provide across a first pair of DC terminals a first DC voltage; and
- a circuit arrangement connected with the DC terminals and functional to provide a high-frequency ballast output voltage between a pair of ballast output terminals; the ballast output terminals being operable to connect with a gas discharge lamp; the high-frequency ballast output voltage being of magnitude sufficient to ignite such a gas discharge lamp and to supply it with high-frequency lamp current.
- 12. The arrangement of claim 11 wherein the narrow pulses are operative to cause the peak absolute magnitude of the line current to be at least 25% higher than what it be absent the narrow pulses.
- 13. The arrangement of claim 11 wherein each of the narrow pulses has a duration not longer than 25% of the duration of each half-cycle of the AC power line voltage.
- 14. An arrangement for ballasting a gas discharge lamp, comprising:
- a power line providing a substantially sinusoidal AC power line voltage at a pair of power line conductors; the power line conductors being electrically connected with earth ground;
- a rectifier arrangement connected with the power line conductors and operative: (i) to draw a line current therefrom; and (ii) to provide a first DC voltage across a first pair of DC terminals; the instantaneous absolute magnitude of the first DC voltage being substantially equal to that of the AC power line voltage; and
- a circuit arrangement connected with the first pair of DC terminals and functional to provide a high-frequency ballast output voltage between a pair of ballast output terminals; the ballast output terminals being operable to connect with a gas discharge lamp; the high-frequency ballast output voltage being of magnitude sufficient to ignite such a gas discharge lamp and to supply it with a high-frequency lamp current; the circuit arrangement being characterized by including an inverter circuit supplied with DC power from a second pair of DC terminals across which exists a second DC voltage of substantially constant magnitude; at least part of the DC power supplied to the inverter circuit being derived from the ballast output terminals by way of an auxiliary DC source means connected in circuit with the ballast output terminals as well as with the second pair of DC terminals.
- 15. An arrangement for ballasting a gas discharge lamp, comprising:
- a power line providing a substantially sinusoidal AC power line voltage at a pair of power line conductors; the power line conductors being electrically connected with earth ground;
- a primary DC source connected with the power line conductors and operative: (i) to draw a line current therefrom; and (ii) to provide a primary DC voltage across a pair of primary DC terminals; the instantaneous absolute magnitude of the primary DC voltage being substantially equal to that of the AC power line voltage;
- an inverter circuit being provided with main DC power from a pair of main DC terminals across which exists a main DC voltage of absolute magnitude about equal to that of the peak absolute magnitude of the AC power line voltage; the inverter circuit being functional to provide a high-frequency ballast output voltage between a pair of ballast output terminals; the ballast output terminals being operable to connect with a gas discharge lamp; the high-frequency ballast output voltage being of magnitude sufficient to ignite such a gas discharge lamp and to supply it with a high-frequency lamp current; and
- an auxiliary DC source connected in circuit with the ballast output terminals and operative to provide an auxiliary DC voltage at a pair of auxiliary DC terminals; the auxiliary DC voltage having an instantaneous absolute magnitude about equal to the difference between the peak absolute magnitude of the AC power line voltage and the instantaneous absolute magnitude of the AC power line voltage; the auxiliary DC source being functional to deliver a substantial part of the DC power drawn by the inverter circuit from the main DC terminals;
- the auxiliary DC source and the primary DC source being series-connected across the main DC terminals by way of their respective auxiliary and primary DC terminals.
- 16. An arrangement for ballasting a gas discharge lamp, comprising:
- a primary DC source operative to provide primary DC power from a pair of primary DC terminals; a primary DC voltage existing between the primary DC terminals; the instantaneous absolute magnitude of the primary DC voltage being substantially equal to that of the AC power line voltage on an ordinary electric utility power line;
- an auxiliary DC source operative to provide auxiliary DC power from a pair of auxiliary DC terminals; an auxiliary DC voltage existing between the auxiliary DC terminals; the instantaneous absolute magnitude of the auxiliary DC voltage being equal to the difference between the absolute magnitude of a main DC voltage and the instantaneous absolute magnitude of the AC power line voltage; the auxiliary source being connected in series with the primary DC source such as to form a combination DC source having a pair of combination DC terminals, thereby causing: (i) any current flowing from the combination DC terminals to flow between the primary DC terminals as well as between the auxiliary DC terminals; and (ii) any voltage existing between the combination DC terminals to have an absolute magnitude equal to that of the main DC voltage; and
- an inverter circuit connected with, and drawing main DC power from, the combination DC terminals; the inverter circuit being functional to provide a high-frequency ballast output voltage from a pair of ballast output terminals; the ballast output terminals being operable to connect with a gas discharge lamp; the high-frequency ballast output voltage being of magnitude sufficient to ignite such a gas discharge lamp and to supply it with a high-frequency lamp current.
- 17. The arrangement of claim 16 wherein the auxiliary DC power supplied from the auxiliary DC source represents a significant part of the main DC power drawn from the combined DC terminals by the inverter circuit.
- 18. The arrangement of claim 16 wherein: (i) the primary DC source is connected in circuit with the power line conductors of an ordinary electric utility power line; and (ii) the auxiliary source is connected in circuit with the ballast output terminals.
- 19. The arrangement of claim 16 wherein the absolute magnitude of the main DC voltage is substantially equal to the peak absolute magnitude of the AC power line voltage.
- 20. The arrangement of claim 16 wherein the magnitude of the main DC voltage is substantially constant.
- 21. An arrangement for ballasting a gas discharge lamp, comprising:
- a primary DC source operative to provide primary DC power from a pair of primary DC terminals; a primary DC voltage existing between the primary DC terminals; the instantaneous absolute magnitude of the primary DC voltage being substantially equal to that of the AC power line voltage on an ordinary electric utility power line;
- an auxiliary DC source operative to provide auxiliary DC power from a pair of auxiliary DC terminals; an auxiliary DC voltage existing between the auxiliary DC terminals; the instantaneous magnitude of the auxiliary DC voltage being a function of the instantaneous magnitude of the DC current flowing from the auxiliary DC terminals, such that (i) when essentially no DC current is flowing therefrom, the magnitude of the auxiliary DC voltage is equal to a certain maximum DC voltage magnitude, and (ii) when DC current of a certain maximum DC current magnitude is flowing therefrom, the magnitude of the auxiliary DC voltage is essentially zero; the auxiliary DC source being connected in series with the primary DC source such as to form a combination DC source having a pair of combination DC terminals, thereby causing (i) any current flowing from the combination DC terminals to flow between the primary DC terminals as well as between the auxiliary DC terminals, and (ii) any voltage existing between the combination DC terminals, herein defined as a main DC voltage, to have an absolute magnitude equal to the sum of the absolute magnitude of the primary DC voltage and that of the auxiliary DC voltage; and
- an inverter circuit connected with, and drawing main DC power from, the combination DC terminals; the inverter circuit being functional (i) to cause the absolute magnitude of the main DC voltage to be substantially constant, and (ii) to provide a high-frequency ballast output voltage from a pair of ballast output terminals; the ballast output terminals being operable to connect with a gas discharge lamp; the high-frequency ballast output voltage being of magnitude sufficient to ignite such a gas discharge lamp and to supply it with a high-frequency lamp current.
- 22. The arrangement of claim 21 wherein the absolute value of the certain maximum DC voltage magnitude is substantially equal to the peak absolute magnitude of the AC power line voltage.
- 23. The arrangement of claim 21 wherein: (i) the primary DC source is connected with the AC power line voltage of an ordinary electric utility power line and draws an AC line current therefrom; and (ii) the peak absolute magnitude of the AC line current is approximately equal to the absolute value of said certain maximum DC current magnitude.
- 24. The arrangement of claim 21 including prevention means (i) connected in circuit with the combination DC terminals, as well as with the auxiliary DC terminals, and (ii) operative to prevent the absolute magnitude of the main DC voltage from exceeding a predetermined absolute magnitude.
- 25. The arrangement of claim 24 wherein said predetermined absolute magnitude is higher than the peak absolute magnitude of the AC power line voltage.
- 26. The arrangement of claim 21 wherein the average DC power supplied from the auxiliary DC terminals is at least 10%, but not larger than about 30%, of the average power supplied from the primary DC terminals; average DC power being defined as DC power averaged over a complete cycle of the AC power line voltage.
- 27. An arrangement for ballasting a gas discharge lamp, comprising:
- a power line providing a substantially sinusoidal AC power line voltage at a pair of power line conductors; the power line conductors being electrically connected with earth ground;
- an inverter circuit having a pair of DC supply terminals and being functional to provide a high-frequency ballast output voltage from a pair of ballast output terminals; the ballast output terminals being operable to connect with a gas discharge lamp; the high-frequency ballast output voltage being of magnitude sufficient to ignite such a gas discharge lamp and to supply it with a high-frequency lamp current; and
- a voltage conditioning circuit connected between the power line conductors and the DC supply terminals; the voltage conditioning circuit being operative: (i) to draw line current from the power line conductors in an intermittent manner and in such a way that, whenever line current is in fact being drawn, it is of substantially sinusoidal waveshape; and (ii) to maintain a DC supply voltage of substantially constant magnitude across the DC supply terminals despite the intermittent manner in which line current is drawn.
- 28. The arrangement of claim 27 wherein the voltage conditioning circuit includes: (i) a primary DC source operative to provide a primary DC voltage across a pair of primary DC terminals; and (ii) an auxiliary DC source operative to provide an auxiliary DC voltage across a pair of auxiliary DC terminals;
- the primary DC source being connected in series with the auxiliary DC source such as to form a combination DC source having a pair of combination DC terminals; which pair of combination DC terminals is connected across the DC supply terminals.
- 29. The arrangement of claim 28 including a shorting means connected in circuit with the DC supply terminals and the auxiliary DC terminals; the shorting means being responsive to the magnitude of the DC supply voltage and operative, in case the magnitude of the DC supply voltage were to exceed a predetermined level, to cause a short-circuit to be placed across the auxiliary DC terminals.
- 30. The arrangement of claim 27 wherein the line current is characterized by having total harmonic distortion not higher than about 20%.
- 31. The arrangement of claim 27 wherein the DC supply voltage is characterized by remaining within plus-minus 10% of a given reference level.
- 32. An arrangement for ballasting a gas discharge lamp, comprising:
- a power line providing a substantially sinusoidal AC power line voltage at a pair of power line conductors; the power line conductors being electrically connected with earth ground;
- a rectifier arrangement connected with the power line conductors and operative: (i) to draw therefrom a line current characterized by having a total harmonic distortion no higher than about 10%; and (ii) to provide a primary DC voltage between a pair of primary DC terminals;
- an inverter circuit having a pair of main DC terminals across which exists a main DC voltage; the inverter circuit being operative to draw primary DC power from the primary DC terminals and to provide high-frequency ballast output power from a set of ballast output terminals; the ballast output terminals being operable to connect with and to power a gas discharge lamp with high-frequency lamp current of crest-factor no higher than 1.7; and
- an auxiliary DC source connected in circuit with the ballast output terminals as well as with the main DC terminals and the primary DC terminals; the auxiliary DC source being operative to draw high-frequency power from the ballast output terminals and to supply auxiliary DC power from a pair of auxiliary DC terminals to the main DC terminals; the auxiliary DC power supplied to the main DC terminals being, on average, substantially lower than the primary DC power drawn from the primary DC terminals.
RELATED APPLICATION
This application is a continuation of Ser. No. 07/912,261 filed Jul. 13, 1992, now abandoned and a Continuation-in-Part of Ser. No. 07/901,989 filed Jun. 22, 1992, now U.S. Pat. No. 5,469,028, issued Nov. 21, 1995.
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Kind |
4560908 |
Stupp et al. |
Dec 1985 |
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5032767 |
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Continuations (1)
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Number |
Date |
Country |
Parent |
912261 |
Jul 1992 |
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