US3748489A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Static synchronizer for alternating current generators
Assignee: Westinghouse Electric Corp
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Filing: 1972-06-13
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Granted: 1973-07-24
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Expires: 1992-06-13
Abstract
Abstract A synchronizer for matching the voltage and frequency of a relatively lower rating alternating current generator to those of an alternating current bus or line to which the generator is to be connected. A circuit breaker is interposed between the generator and bus to complete the circuit between them upon command from the synchronizer. The voltage and frequency on both sides of the circuit breaker are sensed and supplied to the synchronizer circuit in signal form. The voltages and frequencies are then beat together and supplied to a switch means. If both of the composite voltage and frequency values are within acceptable limits for connecting the AC generator to the bus or line, sufficient electrical current is supplied to the switch means to overcome the bias supply and trigger the switch means to cause closing of the circuit breaker. A dead bus system is included which allows the closing of the circuit breaker if the bus is either dead or at a voltage significantly below the voltage of the alternating current generator when the generator is to be connected to the line. A seal-in circuit is also provided so that once the switch means has been actuated to close the circuit breaker, the circuit closing cycle will be completed even though the frequency and voltage of the previously mentioned alternating current generator and line begin to vary with respect to each other slightly. This is possible, if the alternating current generator is sufficiently low in volt-ampere rating to allow bringing the generator onto a slightly imperfectly matched bus or line without significant bump or system disturbance. The previously mentioned switch means is part of a controller circuit having the capability of sensing an unfiltered beat frequency signal and responding thereto.
Inventors
- 👤 W South
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 06:59
CPC Classifications
H; H02; H02J; H02J3/00; H02J3/38; H02J3/40; H02J3/42
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
497 words
An automatic synchronizer of the type adapted to control an electric circuit interrupter which is used to connect an alternating current electrical generator with an electric network, comprising: a first means for sensing the frequency and voltage amplitude in at least one phase of said alternating current electrical generator and for providing an output signal proportional thereto, a second means for sensing the frequency and voltage amplitude in at least one phase of said electrical network and for providing an output signal proportional thereto, input transformer means connected to both said first and second sensing means for the purpose of vectorially adding said previously mentioned output signals to produce an unfiltered carrier signal which is modulated at the beat frequency of both said previously mentioned output signals to produce a beat frequency signal which is related to the differences in frequencies and voltage amplitudes of the previously mentioned signals, said previously mentioned beat frequency modulated carrier signal being produced at a first pair of output terminals on said input transformer means, said input transformer means including a transformer having a primary winding and a secondary winding and a second pair of output terminals which are connected across the secondary winding of said transformer of said input transformer means, the primary winding of said transformer being connected to said second sensing means, a static controller means including first static switch means having a control terminal and output terminals, and a static relay coil driver means which also has input terminals connected to said first static switch means and output terminals, said static controller being electrically connected in circuit relationship with said input transformer means to receive at least a portion of said beat frequency signal as an input signal at said control terminal of said first static switch means and to provide an output signal at said output terminals of said static relay coil driver means which is capable of energizing a relay means when said at least a portion of said beat frequency signal rEaches a predetermined level of amplitude, a relay means having contacts and a relay coil, said contacts being actuated to a predetermined state when said relay coil is energized by said previously mentioned output signal being applied to said relay means, said relay means having at least two output terminals one of which has a higher absolute value of voltage present thereon than the other when said relay coil is energized, a circuit interrupter with closing means and movable contacts, said circuit interrupter closing means being connected in circuit relationship to said previously mentioned relay contacts whereby said circuit interrupter closing means is energized to actuate said circuit interrupter to a state to effect the circuit relationship or said generator and said network with respect to each other when said relay contacts are actuated; and a power supply means to energize said automatic synchronizer having one terminal thereon at a voltage value of generally relatively higher average absolute value than another terminal thereon.
Claim 2
Dependent Claim
497 words
An automatic synchronizer of the type adapted to control an electric circuit interrupter which is used to connect an alternating current electrical generator with an electric network, comprising: a first means for sensing the frequency and voltage amplitude in at least one phase of said alternating current electrical generator and for providing an output signal proportional thereto, a second means for sensing the frequency and voltage amplitude in at least one phase of said electrical network and for providing an output signal proportional thereto, input transformer means connected to both said first and second sensing means for the purpose of vectorially adding said previously mentioned output signals to produce an unfiltered carrier signal which is modulated at the beat frequency of both said previously mentioned output signals to produce a beat frequency signal which is related to the differences in frequencies and voltage amplitudes of the previously mentioned signals, said previously mentioned beat frequency modulated carrier signal being produced at a first pair of output terminals on said input transformer means, said input transformer means including a transformer having a primary winding and a secondary winding and a second pair of output terminals which are connected across the secondary winding of said transformer of said input transformer means, the primary winding of said transformer being connected to said second sensing means, a static controller means including first static switch means having a control terminal and output terminals, and a static relay coil driver means which also has input terminals connected to said first static switch means and output terminals, said static controller being electrically connected in circuit relationship with said input transformer means to receive at least a portion of said beat frequency signal as an input signal at said control terminal of said first static switch means and to provide an output signal at said output terminals of said static relay coil driver means which is capable of energizing a relay means when said at least a portion of said beat frequency signal rEaches a predetermined level of amplitude, a relay means having contacts and a relay coil, said contacts being actuated to a predetermined state when said relay coil is energized by said previously mentioned output signal being applied to said relay means, said relay means having at least two output terminals one of which has a higher absolute value of voltage present thereon than the other when said relay coil is energized, a circuit interrupter with closing means and movable contacts, said circuit interrupter closing means being connected in circuit relationship to said previously mentioned relay contacts whereby said circuit interrupter closing means is energized to actuate said circuit interrupter to a state to effect the circuit relationship or said generator and said network with respect to each other when said relay contacts are actuated; and a power supply means to energize said automatic synchronizer having one terminal thereon at a voltage value of generally relatively higher average absolute value than another terminal thereon.
Claim 3
Dependent Claim
206 words
The combination as claimed in claim 1, wherein a seal-in means having at least two terminals is provided, one of said terminals of said seal-in means being connected to said terminal on said relay means having said higher absolute value of voltage present thereon when said relay coil is energized and the other terminal of said seal-in means being connected in current relationship with said control terminal of said first static switch means of said static controller means, said seal-in means responding to the application of said output signal to said relay means for temporarily changing said portion of said beat frequency signal supplied to said static controller means to thereby delay deenergization of said relay coil after said relay means is energized for the purpose of actuating said circuit interrupter to cause connection of said generator means to said electric network, whereby said relay coil will remain energized until said voltage and frequency of said at least one phase of said generator is substantially equal to said voltage and frequency of said at least one corresponding phase of said electric network and said connection will be made with a minimum internal readjustment of the voltage and frequency values between said generator and said electric network.
Claim 4
Dependent Claim
113 words
The combination as claimed in claim 2, wherein a dead bus actuator means is connected in circuit relationship across said pair of output terminals of said input transformer means and includes an output terminal which is connected to said static relay coil driver means of said static controller means, said dead bus actuator being capable of providing a signal to said static relay coil driver means for the purpose of energizing said relay coil when said signal from said second means for sensing the frequency and voltage amplitude of said at least one phase of said electrical network indicates the absolute value of said voltage of said phase is below a predetermined value.
Claim 5
Dependent Claim
88 words
The combination as claimed in claim 3, whereby said static controller means includes a timer means which is connected in circuit relationship with said first static switch means and said relay coil driver means, said timer means being actuated by said first static switch means once per cycle of said carrier signal but only providing a signal to actuate said static relay coil driver means when said portion of said carrier modulating beat frequency signal reaches said predetermined level of amplitude and remains so for a predetermined time.
Claim 6
Dependent Claim
78 words
The combination as claimed in claim 4, wherein a bias power supply means is connected in circuit relationship across said pair of output terminals of said input transformer means and includes an output terminal which is connected to said control terminal of said static switch means of said static controller means for providing a bias signal for said control terminal of said static switch means to thereby provide said predetermined level of amPlitude for said beat frequency signal.
Claim 7
Dependent Claim
78 words
The combination as claimed in claim 2, wherein said bias power supply means is connected in circuit relationship across said pair of output terminals on said input transformer means and includes an output terminal which is connected to said control terminal of said static switch means of said static controller means for providing a bias signal for said control terminal of said static switch means to thereby provide said predetermined level of amplitude for said beat frequency signal.
Claim 8
Dependent Claim
88 words
The combination as claimed in claim 2 wherein said static controller means includes a timer means which is connected in circuit relationship with said first static switch means and said relay coil driver means, said timer means being actuated by said first static switch means once per cycle of said carrier signal but only providing a signal to actuate said static relay coil driver means when said portion of said carrier modulating beat frequency signal reaches said predetermined level of amplitude and remains so for a predetermined time.
Claim 9
Dependent Claim
78 words
The combination as claimed in claim 7, wherein a bias power supply means is connected in circuit relationship across said pair of output terminals of said input transformer means and includes an output terminal which is connected to said control terminal of said static switch means of said static controller means for providing a bias signal for said control terminal of said static switch means to thereby provide said predetermined level of amplitude for said beat frequency signal.
Claim 10
Dependent Claim
78 words
The combination as claimed in claim 3, wherein a bias power supply means is connected in circuit relationship across said pair of output terminals of said input transformer means and includes an output terminal which is connected to said control terminal of said static switch means of said static controller means for providing a bias signal for said control terminal of said static switch means to thereby provide said predetermined level of amplitude for said beat frequency signal.
Claim 11
Dependent Claim
111 words
The combination as claimed in claim 1, wherein a dead bus actuator means is connected in circuit relationship across said pair of output terminals of said input transformer means and includes an output terminal thereon which is connected to said static relay coil driver means of said static controller means, said dead bus actuator being capable of providing a signal to said static relay coil driver means for energizing said relay coil when said signal from said second means for sensing the frequency and voltage amplitude of said at least one phase of said electrical network indicates the absolute value of said voltage of said phase is below a predetermined value.
Claim 12
Dependent Claim
90 words
The combination as claimed in claim 10 wherein said static controller means includes a timer means which is connected in circuit relationship with said first static switch means and said relay coil driver means, said timer means being actuated by said first static switch means once per cycle of said carrier signal but only providing a signal to actuate said static relay coil driver means when said portion of said carrier modulating beat frequency signal reaches said predetermined level of amplitude and remains at that level for a predetermined time.
Claim 13
Dependent Claim
76 words
The combination claimed in claim 11, wherein bias power supply means is connected in circuit relationship across said pair of output terminals of said input transformer means and includes an output terminal which is connected to said control terminal of said static switch means of said static controller means for providing a bias signal for said control terminal of said static switch means to thereby provide said predetermined level of amplitude for said beat frequency signal.
Claim 14
Dependent Claim
79 words
The combination as claimed in claim 10, wherein a bias power supply means is connected in circuit relationship across said pair of output terminals of said input transformer means and includes having an output terminal which is connected to sAid control terminal of said static switch means of said static controller means for providing a bias signal for said control terminal of said static switch means to thereby provide said predetermined level of amplitude for said beat frequency signal.
Claim 15
Dependent Claim
90 words
The combination as claimed in claim 1 wherein said static controller means includes a timer means which is connected in circuit relationship with said first static switch means and said relay coil driver means, said timer means being actuated by said first static switch means once per cycle of said carrier signal but only providing a signal to actuate said static relay coil driver means if said portion of said carrier modulating beat frequency signal has passed through said predetermined level of amplitude and remained therepast for a predetermined time.
Claim 16
Dependent Claim
82 words
The combination as claimed in claim 14, wherein a bias power supply means is connected in circuit relationship across a said pair of output terminals on said input transformer means, having an output terminal thereon which is connected to said control terminal of said static switch means of said static controller means for the purpose of providing a bias signal for said control terminal of said static switch means to thereby provide said predetermined level of amplitude for said beat frequency signal.
Claim 17
Dependent Claim
82 words
The combination as claimed in claim 1, wherein a bias power supply means is connected in circuit relationship across a said pair of output terminals on said input transformer means, having an output terminal thereon which is connected to said control terminal of said static switch means of said static controller means for the purpose of providing a bias signal for said control terminal of said static switch means to thereby provide said predetermined level of amplitude for said beat frequency signal.
Claim 18
Dependent Claim
208 words
The combination as claimed in claim 1, wherein a seal-in means having at least two terminals is provided, one said terminal being connected to said terminal on said relay means having said higher absolute value of voltage present thereon when said relay coil is energized and the other terminal being connected in circuit relationship with said control terminal of said static switch means of said static controller means, said seal in means responding to the application of said output signal to said relay means for the purpose of temporarily changing said predetermined level of amplitude at which said beat frequency signal will cause energization of said relay means to thereby delay deenergization of said relay coil so that after said relay means is actuated for the purpose of actuating said circuit interrupter to cause connection of said generator means to said electric network, said relay coil will thereby remain energized until said voltage and frequency of said at least one phase of said generator is substantially equal to said voltage and frequency of said at least one corresponding phase of said electric network so that said connection will be made with a minimum internal readjustment of the respective voltage and frequency values of said generator and electric network.
Claim 19
Dependent Claim
463 words
The combination as claimed in claim 1 wherein, said static controller means includes a timer means comprising a capacitive element connected in series circuit relationship with a resistive element and in parallel circuit relationship with said output terminals of said first static switch means of said static controller means, said series combination of said capacitive and resistive elements being connected at one end thereof to the control terminal of a second static switch means, one output terminal of which is connected to the control terminal of a third static switch relay coil driver means and the other output terminal of which is connected to said terminal of higher average absolute value of voltage of said power supply means, said third static switch means having an output terminal connected to said relay means and another output terminal connected to one said terminal on saiD power supply means and allowing electrical energy to flow through said relay means from said power supply means only when said control terminal of said third static switch means is substantially not connected to said terminal of higher average absolute value of said power supply means through said output terminals of said second static switch means when not actuated to the ON state, said first static switch means of said static controller means providing substantially an electrically conducting path across said capacitive element when said first static switch means is in the ON state, thus providing a current path for electrical current flowing through the control terminal of said second static switch, and keeping the second static switch in the ON state so that the control terminal of said third static switch is substantially connected to the previously mentioned terminal of said power supply means normally keeping said third static switch in the off state and preventing the previously mentioned flow of energy to said relay means, when said first static switch means is placed in the OFF state, said capacitive element is charged by current flowing through said resistive element and said control terminal of said second static switch at a rate sufficient to charge the capacitive element to a voltage value capable of changing the state of said second static switch from on to off so that the control terminal of said third static switch is then substantially not connected to said corresponding mentioned terminal of said power supply means thus turning said third static switch on to thereby allow energy to flow to said relay means, said timer means being actuated by said first static switch once per cycle of said carrier signal but only providing a signal to energize said relay when said portion of said carrier modulating beat frequency signal has passed through said predetermined level of amplitude and remained there for a predetermined time.
Claim 20
Dependent Claim
257 words
The combination as claimed in claim 18 wherein said seal in means comprises a first static device having a control terminal and first and second output terminals thereon, said control terminal being connected to said terminal on said relay means having said higher absolute value of voltage present thereon when said relay coil is energized, said first and second output terminals of said first static device being connected in parallel circuit relationship with said first pair of output terminals on said input transformer means and with said static controller means so that a portion of said unfiltered carrier signal is shunted away from said control terminal of said first static switch means of said static controller means in response to said application of said output signal at said output terminals of said static relay coil driver at said relay means for the purpose of temporarily changing said portion of said beat frequency signal supplied to said static controller means to thereby delay deenergization of said relay coil so that after said relay means is actuated for the purpose of actuating said circuit interrupter to cause connection of said generator means to said electric network, whereby said relay coil will remain energized until said voltage and frequency of said at least one phase of said generator is substantially equal to said voltage and frequency of said at least one corresponding phase of said electric network and said connection will be made with a minimum internal readjustment of voltage and frequency values between said generator and said electric network.
Claim 21
Dependent Claim
121 words
The combination as claimed in claim 19 wherein said bias supply means comprises a half wave rectifier connected in series circuit relationship with a voltage divider means, the later series combination being connected across said second pair of output terminals of said input transformer means to thereby energize said bias supply means, said voltage divider means having an intermediate output terminal connected in circuit relationship to said control terminaL of said first static switch means of said static controller means, electric current flowing between said voltage divider output terminal and said first static switch means control terminal providing a bias signal to said control terminal of said static controller to provide said predetermined level of amplitude for said beat frequency signal.
Claim 22
Dependent Claim
123 words
The combination as claimed in claim 18 wherein said bias supply means comprises a half wave rectifier connected in series circuit relationship with a voltage divider means, the later series combination being connected across said second pair of output terminals of said input transformer means to thereby energize said bias supply means, said voltage divider means having an intermediate output terminal connected in current relationship to said control terminal of said first static switch means of said static controller means, the electric current which flows between said voltage divider output terminal and said first static switch means control terminal providing a bias signal to said control terminal of said static controller to provide said predetermined level of amplitude for said beat frequency signal.
Claim 23
Dependent Claim
256 words
The combination as claimed in claim 1 wherein seal in means comprises a first static device having a control terminal and first and second output terminals thereon, said control terminal being connected to said terminal on said relay means having said higher absolute value of voltage present thereon when said relay coil is energized, said first and second output terminals of said first static device being connected in parallel circuit relationship with said first pair of output terminals on said input transformer means and with said static controller means such that a portion of said unfiltered carrier signal is shunted away from said control terminal of said first static switch means of said static controller means in response to said application of said output signal at said output terminals of said static relay coil driver at said relay means for the purpose of temporarily changing said portion of said beat frequency signal supplied to said static controller means to delay deenergization of said relay coil so that after said relay means is actuated for the purpose of actuating said circuit interrupter to cause connection of said generator means to said electric network, said relay coil will thereby remain energized until said voltage and frequency of said at least one phase of said generator is substantially equal to said voltage and frequency of said at least one corresponding phase of said electric network so that said connection will be made with a minimum internal readjustment of voltage and frequency values between said generator and said electric network.
Claim 24
Dependent Claim
123 words
The combination as claimed in claim 22 wherein said bias supply means comprises a half wave rectifier connected in series circuit relationship with a voltage divider means, the later series combination being connected across said second pair of output terminals of said input transformer means to thereby energize said bias supply means, said voltage divider means having an intermediate output terminal connected in circuit relationship to said control terminal of said first static switch means of said static controller means, the electric current which flows between said voltage divider output terminal and said first static switch means control terminal providing a bias signal to said control terminal of said static controller to provide said predetermined level of amplitude for said beat frequency signal.
Claim 25
Dependent Claim
122 words
The combination claimed in claim 1 wherein said bias supply means comprises a half wave rectifier connected in series circuit relationship with a voltage divider means, the later series combination being connected across said second pair of output terminals of said input transformer means to thereby energize said bias supply means, said voltage divider means having an intermediate output terminal connected in circuit relationship with said control terminAl of said first static switch means of said static controller means, the electric current which flows between said voltage divider output terminal and said first static switch means control terminal providing a bias signal to said control terminal of said static controller to provide said predetermined level of amplitude for said beat frequency signal.
References Cited (Backward Citations)
US3069555A
Cited
US3497711A
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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) | 1976-07-23 | 1977-01-22 | 1977-07-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-23 | 1981-01-22 | 1981-07-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-23 | 1985-01-22 | 1985-07-24 | $7700.00 | Window Closed / Lapsed |