Patent US4392337A successfully refreshed from Google Patents.
Patent US3601619A successfully refreshed from Google Patents.
US3601619A
Expired / Lapsed
US
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Automatic synchronizing monitor for parallel connection of two separate alternating-current sources
Assignee: Automatic Switch Co
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Filing: 1969-12-03
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Granted: 1971-08-24
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Expires: 1989-12-03
Abstract
Abstract An automatic synchronizing monitor enabling the connection of two separate alternating-current sources in parallel and, more particularly, to permit parallel connection of the alternatingcurrent sources when the phase angle, frequency, and voltage of the sources are substantially equal to one another and within predetermined limits so as to limit the resultant disturbance on a common bus to an absolute minimum when the paralleling takes place.
Inventors
- 👤 Ralph H Ringstad
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:05
CPC Classifications
H; H02; H02J; H02J3/00; H02J3/38; H02J3/40; H02J3/42
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
240 words
An automatic synchronizing monitor for connecting one AC source in parallel with another AC source when the phase, frequency, and voltage of said one source are substantially equal to the phase, frequency, and voltage, respectively, of said other source, said monitor comprising: means for connecting said sources as inputs to said monitor, output switching means to enable the parallel connection of said sources, a pulse generator operatively connected to said output switching means, inhibiting means connected to said pulse generator for inhibiting operation of the latter, means for comparing the phase angle difference between said sources and for supplying a signal to said pulse generator to active the latter only when said phase angle difference is within predetermined limits, means for comparing the frequency differential between said sources and for supplying a signal to said inhibiting means only when said frequency differential is within predetermined limits, and means for comparing the voltage magnitude differential between said sources and for supplying a signal to said inhibiting means only when said voltage magnitude differential is within predetermined limits, said inhibiting means being operative only upon the reception of simultaneous signals from said frequency and voltage magnitude comparing means to discontinue inhibiting said pulse generator and permit the latter to produce a signal in response to receipt of a signal from said phase-comparing means, said pulse generator signal serving to activate said output switching means to thereby connect said sources for parallel operation.
Claim 2
Dependent Claim
240 words
An automatic synchronizing monitor for connecting one AC source in parallel with another AC source when the phase, frequency, and voltage of said one source are substantially equal to the phase, frequency, and voltage, respectively, of said other source, said monitor comprising: means for connecting said sources as inputs to said monitor, output switching means to enable the parallel connection of said sources, a pulse generator operatively connected to said output switching means, inhibiting means connected to said pulse generator for inhibiting operation of the latter, means for comparing the phase angle difference between said sources and for supplying a signal to said pulse generator to active the latter only when said phase angle difference is within predetermined limits, means for comparing the frequency differential between said sources and for supplying a signal to said inhibiting means only when said frequency differential is within predetermined limits, and means for comparing the voltage magnitude differential between said sources and for supplying a signal to said inhibiting means only when said voltage magnitude differential is within predetermined limits, said inhibiting means being operative only upon the reception of simultaneous signals from said frequency and voltage magnitude comparing means to discontinue inhibiting said pulse generator and permit the latter to produce a signal in response to receipt of a signal from said phase-comparing means, said pulse generator signal serving to activate said output switching means to thereby connect said sources for parallel operation.
Claim 3
Dependent Claim
47 words
An automatic synchronizing monitor in accordance with claim 1, wherein said pulse generator supplies an activating signal to said switching means in advance of the true in phase condition of said sources, whereby connection of said sources for parallel operation occurs at said true in phase condition.
Claim 4
Dependent Claim
21 words
An automatic synchronizing monitor in accordance with claim 1, including a pulse amplifier connected to the output of said pulse generator.
Claim 5
Dependent Claim
21 words
An automatic synchronizing monitor in accordance with claim 3, including stored energy module connected to the output of said pulse amplifier.
Claim 6
Dependent Claim
55 words
An automatic synchronizing monitor in accordance with claim 1, wherein said phase-comparing means comprises a gate circuit, and said gate circuit having said sources connected as inputs thereto, the output of said gate being connected to said phase comparator, and the output of said phase comparator being connected to the input of said pulse generator.
Claim 7
Dependent Claim
23 words
An automatic synchronizing monitor in accordance with claim 5, including a first inverter circuit between said gate circuit and said phase comparator circuit.
Claim 8
Dependent Claim
49 words
An automatic synchronizing monitor in accordance with claim 5, wherein said frequency comparing means comprises a frequency difference detector, the output of said gate circuit being connected to the input of said frequency difference detector, and the output of said frequency difference detector being connected to said inhibiting means.
Claim 9
Dependent Claim
23 words
An automatic synchronizing monitor in accordance with claim 7, including a second inverter circuit between said gate circuit and said frequency difference detector.
Claim 10
Dependent Claim
44 words
An automatic synchronizing monitor in accordance with claim 7, wherein said voltage comparing means comprises a voltage difference detector, said voltage difference detector having said sources connected as inputs thereto, and the output of said voltage difference detector being connected to said inhibiting means.
Claim 11
Dependent Claim
25 words
An automatic synchronizing monitor in accordance with claim 9, wherein the output of said voltage difference detector is also connected to said frequency difference detector.
Claim 12
Dependent Claim
43 words
An automatic synchronizing monitor in accordance with claim 9, wherein said voltage difference detector includes means to provide an output signal when the voltage of one of said sources is within prescribed percentage limits of the voltage of the other of said sources.
Claim 13
Dependent Claim
47 words
An automatic synchronizing monitor in accordance with claim 9, wherein said gate is an AND gate and is operable to provide a time duration signal to said first and second inverters which is indicative of the time said sources are in phase with respect to each another.
Claim 14
Dependent Claim
70 words
An automatic synchronizing monitor in accordance with claim 9, wherein said inhibiting means comprises a clamp circuit, said clamp circuit being effectively connected to the input of said pulse generator, said clamp circuit in the absence of signals thereto fRom said frequency difference detector and said voltage difference detector providing a shunt path for the signal from said differential phase comparator to thereby inhibit the operation of said pulse generator.
Claim 15
Dependent Claim
70 words
An automatic synchronizing monitor in accordance with claim 13, wherein the output of said voltage difference detector is also connected to said frequency difference detector, and said frequency difference detector is operative to provide a signal to said clamp circuit only when said voltage difference detector supplies an output signal thereto which is indicative of the difference in magnitude between the voltages of said sources being within said prescribed limits.
Claim 16
Dependent Claim
41 words
An automatic synchronizing monitor in accordance with claim 13, wherein said output switching means comprises a relay, and a circuit breaker, said relay being operative to close said circuit breaker upon the reception of an output signal from said pulse generator.
Claim 17
Dependent Claim
41 words
An automatic synchronizing monitor in accordance with claim 13, wherein said output switching means comprises an SCR, and a circuit breaker, said SCR being operative upon the reception of an output signal from said pulse generator to close said circuit breaker.
Claim 18
Dependent Claim
50 words
An automatic synchronizing monitor in accordance with claim 13, wherein said pulse generator is connected to said clamp circuit and is operative to supply a pulse to said clamp circuit to return it to its inhibiting mode of operation whereby said clamp circuit again inhibits operation of said pulse generator.
Claim 19
Dependent Claim
19 words
An automatic synchronizing monitor in accordance with claim 13, wherein said output activating means includes a stored energy module.
Claim 20
Dependent Claim
61 words
An automatic synchronizing monitor in accordance with claim 18, wherein said output switching means comprises a high-speed contactor in conjunction with a main contactor, said high-speed contactor being effective upon the reception of an output pulse from said stored energy module to effect the speedy closure of said high-speed contactor, to thereby connect said first and second sources for parallel operation.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-08-23 | 1975-02-22 | 1975-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-23 | 1979-02-22 | 1979-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-23 | 1983-02-22 | 1983-08-24 | $7700.00 | Window Closed / Lapsed |