Patent US3780347A successfully refreshed from Google Patents.
US3780347A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Power factor correction in a lead/lag ballast circuit
Assignee: General Electric Co
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Filing: 1972-09-27
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Granted: 1973-12-18
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Expires: 1992-09-27
Abstract
Abstract A ballast circuit which comprises an autotransformer and capacitors in a lead/lag circuit arrangement is provided to control current through at least a pair of gaseous discharge lamps. The lead circuit, which comprises a lead primary winding and a lead secondary winding connected to a power capacitor, controls a lead lamp. The lag circuit, which comprises a lag primary winding and a lag secondary winding, controls the current in a lag lamp. A shunt capacitor is connected across the series arrangement comprising the lead primary winding and the lead secondary winding. This shut capacitor provides additional power factor correction to above 90 percent power factor and is further used to tune the circuit for minimum impedance to a selected harmonic which is present in the lead circuit.
Inventors
- 👤 D Riesland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:20
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/14; H05B41/16; H05B41/20; H05B41/23
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
101 words
A lead-lag ballast circuit comprising: a lead primary winding and a lead secondary winding wound on a first magnetic core; a lag primary winding and a lag secondary winding wound on a second magnetic core; a power capacitor; said lead primary winding, said lead secondary winding said power capacitor being connected in a series circuit relationship for operation of a first lamp; a shunt capacitor connected in parallel with said lead primary winding and said lead secondary winding; and said lag primary winding and said lag secondary winding being connected in a series circuit relationship for operation of a second lamp.
Claim 2
Dependent Claim
101 words
A lead-lag ballast circuit comprising: a lead primary winding and a lead secondary winding wound on a first magnetic core; a lag primary winding and a lag secondary winding wound on a second magnetic core; a power capacitor; said lead primary winding, said lead secondary winding said power capacitor being connected in a series circuit relationship for operation of a first lamp; a shunt capacitor connected in parallel with said lead primary winding and said lead secondary winding; and said lag primary winding and said lag secondary winding being connected in a series circuit relationship for operation of a second lamp.
Claim 3
Dependent Claim
72 words
A lead-lag ballast circuit comprising: a lead circuit, including a lead primary winding and a lead secondary winding, for operating a first lamp; power factor correction means connected across said lead primary and secondary windings for increasing the power factor of said lead circuit; and a lag circuit, including a lag primary winding and a lag secondary winding, for operating a second lamp; whereby power factor is increased in the ballast circuit.
Claim 4
Dependent Claim
72 words
A lead-lag ballast circuit comprising: a lead circuit, including a lead primary winding and a lead secondary winding, for operating a first lamp; power factor correction means connected across said lead primary and secondary windings for increasing the power factor of said lead circuit; and a lag circuit, including a lag primary winding and a lag secondary winding, for operating a second lamp; whereby power factor is increased in the ballast circuit.
Claim 5
Dependent Claim
64 words
A ballast circuit as set forth in claim 2 wherein said lead circuit further includes a power capacitor connected in series with said lead primary and secondary windings; and said power factor correction means includes a shunt capacitor having one side connected to the junction of said lead secondary winding and said power capacitor, and the other side connected to said lead primary winding.
Claim 6
Dependent Claim
28 words
A ballast circuit as set forth in claim 3 wherein said shunt capacitor is of a value so as to tune said lead circuit to a selected harmonic.
Claim 7
Dependent Claim
76 words
A lead-lag ballast circuit comprising: a lead primary winding and a lead secondary winding connected in series; a lag primary winding and a lag secondary winding connected in series; a power capacitor connected to the end of said lead secondary winding remote from said lead primary winding; a shunt capacitor connected to said power capacitor and to the end of said lead primary winding remote from said lead secondary winding whereby power factor is substantially improved.
Claim 8
Dependent Claim
76 words
A lead-lag ballast circuit comprising: a lead primary winding and a lead secondary winding connected in series; a lag primary winding and a lag secondary winding connected in series; a power capacitor connected to the end of said lead secondary winding remote from said lead primary winding; a shunt capacitor connected to said power capacitor and to the end of said lead primary winding remote from said lead secondary winding whereby power factor is substantially improved.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-17 | 1977-06-18 | 1977-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-17 | 1981-06-18 | 1981-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-17 | 1985-06-18 | 1985-12-18 | $7700.00 | Window Closed / Lapsed |