US3699424A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Overvoltage protection of dc to dc converters using ferroresonance
Assignee: AT&T Inc
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Filing: 1971-07-06
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Granted: 1972-10-17
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Expires: 1991-07-06
Abstract
Abstract The frequency characteristic of a ferroresonant regulator is shown to have a critical jump frequency above which the output voltage of the regulator takes a sudden drop. A regulated voltage converter utilizes this discontinuity to provide automatic overvoltage protection. An inverter drives a ferroresonant regulator and a feedback loop controls the frequency of the inverter in response to output voltage. A short in the feedback loop drives the frequency above the critical jump frequency to provide automatic voltage limiting.
Inventors
- 👤 Harry Patrick Hart
- 👤 Robert John Kakalec
- 👤 Ralph Walk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 02:39
CPC Classifications
G; G05; G05F; G05F1/00; G05F1/10; G05F1/12; G05F1/13; H; H02; H02M; H02M3/00; H02M3/22; H02M3/24; H02M3/28; H02M3/325; H02M3/335; H02M3/338; H02M3/3385; H02M3/3387; H02M3/3388
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
103 words
A self-limiting voltage regulating system for supplying a regulated voltage to a load comprising a source of ac signals of controllable frequency, a ferroresonant regulator having a saturating core, said ferroresonant regulator connected to be driven by said ac signal and to supply said load and feedback means including an amplifier connected between said load and said ac signal source for controlling the frequency of said ac signals in response to the voltage across said loAd, said feedback means also including means for increasing the frequency of said ac signals higher than will allow said core to saturate when said amplifier is short-circuited.
Claim 2
Dependent Claim
103 words
A self-limiting voltage regulating system for supplying a regulated voltage to a load comprising a source of ac signals of controllable frequency, a ferroresonant regulator having a saturating core, said ferroresonant regulator connected to be driven by said ac signal and to supply said load and feedback means including an amplifier connected between said load and said ac signal source for controlling the frequency of said ac signals in response to the voltage across said loAd, said feedback means also including means for increasing the frequency of said ac signals higher than will allow said core to saturate when said amplifier is short-circuited.
Claim 3
Dependent Claim
49 words
A voltage regulating system as in claim 1 wherein said source of ac signals includes a transformer having a magnetic core and said feedback means includes a winding on said core and an inductor, said inductor being periodically switched across said winding to control the frequency of said signal.
Claim 4
Dependent Claim
43 words
A voltage regulating system as in claim 1 wherein said source of ac signals includes a transformer having a magnetic core and said feedback means includes a winding on said core, said winding being periodically shorted to control the frequency of said signal.
Claim 5
Dependent Claim
23 words
A voltage regulating system as in claim 1 wherein the short-circuiting of said amplifier at least doubles the frequency of said ac signal.
Claim 6
Dependent Claim
143 words
A voltage regulating system for supplying a regulated voltage to a load comprising a ferroresonant regulator having a saturating core and an output winding on said core, said output winding being coupled to said load, a source of ac signals connected to said ferroresonant regulator to drive said core periodically into saturation, and voltage to frequency feedback means connected between said load and said source of ac signals to control the frequency of said signals in response to the voltage across said load, said feedback means including a timing capacitor, a resistance in series with said timing capacitor and a transistor connected across at least a portion of said resistance, said portion being sufficiently large to increase the frequency of said signals higher than will allow said core to saturate when said transistor is shorted, whereby the voltage across said load is limited.
Claim 7
Dependent Claim
143 words
A voltage regulating system for supplying a regulated voltage to a load comprising a ferroresonant regulator having a saturating core and an output winding on said core, said output winding being coupled to said load, a source of ac signals connected to said ferroresonant regulator to drive said core periodically into saturation, and voltage to frequency feedback means connected between said load and said source of ac signals to control the frequency of said signals in response to the voltage across said load, said feedback means including a timing capacitor, a resistance in series with said timing capacitor and a transistor connected across at least a portion of said resistance, said portion being sufficiently large to increase the frequency of said signals higher than will allow said core to saturate when said transistor is shorted, whereby the voltage across said load is limited.
References Cited (Backward Citations)
US3590362A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-17 | 1976-04-17 | 1976-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-17 | 1980-04-17 | 1980-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-17 | 1984-04-17 | 1984-10-17 | $7700.00 | Window Closed / Lapsed |