Synchronization scheme

Claim 2

An indicating system for indicating whenever a signal from a first alternating current source is synchronized with a signal from a second alternating current source, said system comprising: a. a frequency discriminator circuit responsive to the signals from said first and second sources to sense a difference in frequency between said signals and for producing a first output signal when the frequency of the first source signal is higher that that of the second, and a second output signal when the frequency of the second source signal is higher than that of the first; b. an angle discriminator circuit responsive to the signals from said first and second sources to sense a phase angle difference and a frequency difference between said signals, and for generating a phase angle signal occurring during periods of time during which said phase angle difference is less than a predetermined value; said phase angle signal recurring at a rate proportional to said frequency difference between said signals; c. a frequency difference circuit responsive to said recurring phase angle signals to sense a difference in frequency between said signals frOm said first and second sources, and including first switch means for passing a first difference signal whenever said difference in frequency between said signals from said first and second sources is less than a preselected value; and d. means responsive to said phase angle signal, said first output signal and said first difference signal to provide an indicating signal whenever said phase angle signal, said first output signal and said first difference signals are received.

Claim 3

The control system as recited in claim 1 wherein said phase angle signal is a pulse having a pulse width proportional to the period of time said phase angle difference is less than said predetermined value.

Claim 4

An indicating system for indicating whenever a signal from a first alternating current source is synchronized with a signal from a second alternating current source, said system comprising: a. a frequency discriminator circuit responsive to the signals from said first and second sources to sense a difference in frequency between said signals and for producing a first output signal when the frequency of the first source signal is higher than that of the second, and a second output signal when the frequency of the second source signal is higher than that of the first; b. an angle discriminator circuit responsive to the signals from said first and second sources to sense a phase angle difference and a frequency difference between said signals, and for generating a phase angle signal occurring during periods of time during which said phase angle difference is less than a predetermined value; said phase angle signal recurring at a rate proportional to said frequency difference between said signals; c. a frequency difference circuit responsive to said recurring phase angle signals to sense a difference in frequency between said signals from said first and second sources, said frequency difference circuit including first switch means for passing a first difference signal whenever said difference in frequency between said signals from said first and second sources is less than a first preselected value; said frequency difference circuit including second switch means for passing a second difference signal whenever said difference in frequency between said signals from said first and said second sources is greater than a second preselected value; said frequency difference circuit including third switch means for passing third difference signal when said difference in frequency between said signals from said first and second sources is greater than said first preselected value and less than said second preselected value; and d. means responsive to said phase angle signal, said first output signal and said first or second difference signals to provide an indicating signal whenever said phase angle signal, said first output signal and said first or second difference signals are received.

Claim 5

An indicating system for indicating whenever a signal from a first alternating current source is synchronized with a signal from a second alternating current source, said system comprising: a. a frequency discriminator circuit responsive to the signals from said first and second sources to sense a difference in frequency between said signals and for producing a first output signal when the frequency of the first source signal is higher than that of the second, and a second output signal when the frequency of the second source signal is higher than that of the first; b. an angle discriminator circuit responsive to the signals from said first and second sources to sense a phase angle difference and a frequency difference between said signals, and for generating a phase angle signal occurring during periods of time during which said phase angle difference is less than a predetermined value; said phase angle signal recurring at a rate proportional to said frequency difference between said signals; c. a frequency difference circuit responsive to said recurring phase angle signals to sense a difference in frequency between said signals from said first and second sources, said frequency difference circuit including first switch means for passing a first difference signal whenever said difference in frequency between said signals from said first and second sources is less than a first preselected value; said frequency difference circuit including second switch means for passing a second difference signal whenever said difference in frequency between said signals from said first and said second sources is greater than a second preselected value; said frequency difference circuit including third switch means for passing third difference signal when said difference in frequency between said signals from said first and second sources is greater than said first preselected value and less than said second preselected value; and d. means responsive to said phase angle signal, said first output signal and said first or second difference signals to provide an indicating signal whenever said phase angle signal, said first output signal and said first or second difference signals are received.

Claim 6

An indicating system for indicating whenever a signal from a first alternating current source is synchronized with a signal from a second alternating current source, said system comprising: a. a first storage cell responsive to the signals from said first and second sources to provide a first signal whenever the frequency of said signal from said first source is greater than frequency of said signal from said second source; b. a second storage cell responsive to said frequency of said signals from said first and second sources to provide a second signal whenever the frequency of said signal from said first source is less than the frequency of said signal from said second source; c. a third storage cell responsive to said first and second signals to provide a first output signal whenever said first signal is received, and a second output signal whenever said second signal is received; and d. a frequency discriminator circuit responsive to the signals from said first and second sources to sense a difference in frequency between said signals and for producIng a first output signal when the frequency of the first source signal is higher than that of the second, and a second output signal when the frequency of the second source signal is higher than that of the first.

Claim 7

An indicating system for indicating whenever a signal from a first alternating current source is synchronized with a signal from a second alternating current source, said system comprising: a. a first storage cell responsive to the signals from said first and second sources to provide a first signal whenever the frequency of said signal from said first source is greater than frequency of said signal from said second source; b. a second storage cell responsive to said frequency of said signals from said first and second sources to provide a second signal whenever the frequency of said signal from said first source is less than the frequency of said signal from said second source; c. a third storage cell responsive to said first and second signals to provide a first output signal whenever said first signal is received, and a second output signal whenever said second signal is received; and d. a frequency discriminator circuit responsive to the signals from said first and second sources to sense a difference in frequency between said signals and for producIng a first output signal when the frequency of the first source signal is higher than that of the second, and a second output signal when the frequency of the second source signal is higher than that of the first.

Claim 8

A control system for synchronizing a signal from a first alternating current source to a signal from a second alternating current source, said system comprising: a. a frequency discriminator circuit responsive to the signals from said first and second sources to sense a difference in frequency between said signals and for producing a first output signal when the frequency of the first source signal is higher than that of the second, and a second output signal when the frequency of the second source signal is higher than that of the first; b. an angle discriminator circuit responsive to the signals from said first and second sources to sense a phase angle difference and a frequency difference between said signals, and for generating a phase angle signal occurring during periods of time during which said phase angle difference is less than a predetermined value; said phase angle signal recurring at a rate proportional to said frequency difference between said signals; c. a frequency difference circuit responsive to said recurring phase angle signals to sense a difference in frequency between the signals from said first and second sources, and including first switch means for passing a first difference signal whenever said difference in frequency between said signals from said first and second sources is less than a preselected value; and d. a first gating means responsive to said phase angle signal, said first output signal and said first difference signal to provide a synchronization signal for effecting connection of said first source to said second source.

Claim 9

A control system for synchronizing a signal from a first alternating current source to a signal from a second alternating current source, said system comprising: a. a frequency discriminator circuit responsive to the signals from said first and second sources to sense a difference in frequency between said signals and for producing a first output signal when the frequency of the first source signal is higher than that of the second, and a second output signal when the frequency of the second source signal is higher than that of the first; b. an angle discriminator circuit responsive to the signals from said first and second sources to sense a phase angle difference and a frequency difference between said signals, and for generating a phase angle signal occurring during periods of time during which said phase angle difference is less than a predetermined value; said phase angle signal recurring at a rate proportional to said frequency difference between said signals; c. a frequency difference circuit responsive to said recurring phase angle signals to sense a difference in frequency between the signals from said first and second sources, and including first switch means for passing a first difference signal whenever said difference in frequency between said signals from said first and second sources is less than a preselected value; and d. a first gating means responsive to said phase angle signal, said first output signal and said first difference signal to provide a synchronization signal for effecting connection of said first source to said second source.

Claim 10

A control system for synchronizing a signal from a first alternating current source to a signal from a second alternating current source, said system comprising: a. a frequency discriminator circuit responsive to the signals from said first and second sources to sense a difference in frequency between said signals and for producing a first output signal when the frequency of the first source signal is higher than that of the second, and a second output signal when the frequency of the second source signal is higher than that of the first; b. an angle discriminator circuit responsive to the signals from said first and second sources to sense a phase angle difference and a frequency difference between said signals, and for generating a phase angle signal occurring during periods of time during which said phase angle difference is less than a predetermined value; said phase angle signal recurring at a rate proportional to said frequency difference between said signals; c. a frequency difference circuit responsive to said recurring phase angle signals to sense a difference in frequency between said signals from said first and second sources, and including first switch means for passing a first difference signal whenever said difference in frequency between said signals from said first and second sources is less than a first preselected value; second switch means for passing a second difference signal when said difference in frequency between said signals from said first and said second sources is greater than a second preselected value; third switch means for passing a third difference signal said difference in frequency between said signals from said first and second sources is greater than said first preselected value and less than said second preselected value; and d. a first gating means responsive to said phase angle signal, said first output signal and said first or said third difference signal to provide a synchronization signal for effecting connection of said first source to said second source.

Claim 11

A control system for synchronizing a signal from a first alternating current source to a signal from a second alternating current source, said system comprising: a. a frequency discriminator circuit responsive to the signals from said first and second sources to sense a difference in frequency between said signals and for producing a first output signal when the frequency of the first source signal is higher than that of the second, and a second output signal when the frequency of the second source signal is higher than that of the first; b. an angle discriminator circuit responsive to the signals from said first and second sources to sense a phase angle difference and a frequency difference between said signals, and for generating a phase angle signal occurring during periods of time during which said phase angle difference is less than a predetermined value; said phase angle signal recurring at a rate proportional to said frequency difference between said signals; c. a frequency difference circuit responsive to said recurring phase angle signals to sense a difference in frequency between said signals from said first and second sources, and including first switch means for passing a first difference signal whenever said difference in frequency between said signals from said first and second sources is less than a first preselected value; second switch means for passing a second difference signal when said difference in frequency between said signals from said first and said second sources is greater than a second preselected value; third switch means for passing a third difference signal said difference in frequency between said signals from said first and second sources is greater than said first preselected value and less than said second preselected value; and d. a first gating means responsive to said phase angle signal, said first output signal and said first or said third difference signal to provide a synchronization signal for effecting connection of said first source to said second source.

Claim 12

A control system for synchronizing a signal from a first alternating current source to a signal from a second alternating current source, said system Comprising: a. a frequency discriminator circuit responsive to the signals from said first and second sources to sense a difference in frequency between said signals and for producing a first output signal when the frequency of the first source signal is higher than that of the second, and a second output signal when the frequency of the second source signal is higher than that of the first; b. an angle discriminator circuit responsive to the signals from said first and second sources to sense a phase angle difference and a frequency difference between said signals, and for generating a phase angle signal occurring during periods of time during which said phase angle difference is less than a predetermined value; said phase angle signal recurring at a rate proportional to said frequency difference between said signals; c. a frequency difference circuit responsive to said recurring phase angle signals to sense a difference in frequency between said signals from said first and second sources, and including first switch means for passing a first difference signal whenever said difference in frequency between said signals from said first and second sources is less than a first preselected value; second switch means for passing a second difference signal whenever said difference in frequency between said signals from said first and said second sources is greater than a second preselected value; third switch means for producing a third difference signal when said difference in frequency between said signals from said first and second sources is greater than said first preselected value and less than said second preselected value; d. a first gating means having first and second states and being responsive to said phase angle signal, said first output signal and said first or said third difference signal to assume said first state and provide a synchronization signal for effecting connection of said first source to said second source, said first gating means assuming said second state to provide a nonsynchronization signal whenever said phase angle signal, said first output signal and said first or said third difference signals are not present; e. a second gating means responsive to said second output signal and said nonsynchronization signal to initiate a first intermediary control signal; f. a third gating means responsive to said second difference signal, said first output signal and said nonsynchronization signal to initiate a first control signal for causing said frequency of said signal from said first source to increase in a first direction; g. a fourth gating means responsive to said first output signal, said first difference signal and said nonsynchronization signal to initiate a second intermediary control signal; and h. a fifth gating means responsive to said first and second intermediary control signals to initiate a second control signal for causing said frequency of said signal from said first source to increase in a second direction opposite to said first direction.

Claim 13

A control system for synchronizing a signal from a first alternating current source to a signal from a second alternating current source, said system Comprising: a. a frequency discriminator circuit responsive to the signals from said first and second sources to sense a difference in frequency between said signals and for producing a first output signal when the frequency of the first source signal is higher than that of the second, and a second output signal when the frequency of the second source signal is higher than that of the first; b. an angle discriminator circuit responsive to the signals from said first and second sources to sense a phase angle difference and a frequency difference between said signals, and for generating a phase angle signal occurring during periods of time during which said phase angle difference is less than a predetermined value; said phase angle signal recurring at a rate proportional to said frequency difference between said signals; c. a frequency difference circuit responsive to said recurring phase angle signals to sense a difference in frequency between said signals from said first and second sources, and including first switch means for passing a first difference signal whenever said difference in frequency between said signals from said first and second sources is less than a first preselected value; second switch means for passing a second difference signal whenever said difference in frequency between said signals from said first and said second sources is greater than a second preselected value; third switch means for producing a third difference signal when said difference in frequency between said signals from said first and second sources is greater than said first preselected value and less than said second preselected value; d. a first gating means having first and second states and being responsive to said phase angle signal, said first output signal and said first or said third difference signal to assume said first state and provide a synchronization signal for effecting connection of said first source to said second source, said first gating means assuming said second state to provide a nonsynchronization signal whenever said phase angle signal, said first output signal and said first or said third difference signals are not present; e. a second gating means responsive to said second output signal and said nonsynchronization signal to initiate a first intermediary control signal; f. a third gating means responsive to said second difference signal, said first output signal and said nonsynchronization signal to initiate a first control signal for causing said frequency of said signal from said first source to increase in a first direction; g. a fourth gating means responsive to said first output signal, said first difference signal and said nonsynchronization signal to initiate a second intermediary control signal; and h. a fifth gating means responsive to said first and second intermediary control signals to initiate a second control signal for causing said frequency of said signal from said first source to increase in a second direction opposite to said first direction.

Claim 14

The control system as recited in claim 7 wherein said first alternating current source is a power generator and said second alternating current source is an operating power line.

Claim 15

The control system as recited in claim 8 wherein said power generator is a gas turbine generator.

Claim 16

The control system as recited in claim 7 wherein said frequency discriminator circuit comprises: a. a first storage cell responsive to the signals from said first and second sources to provide a first signal whenever the frequency of said signal from said first source is greater than the frequency of said signal from said second source; b. a second storage cell responsive to said frequency of said signals from said first and second sources to provide a second signal whenever the frequency of said signal from said first source is less than the frequency of said signal from said second source; and c. a third storage cell responsive to said first and second signals to provide a first output signal whenever said first signal is received, and a second output signal whenever said second signal is received.

Claim 17

The control system as recited in claim 7 wherein said angle discriminator circuit comprises: a. a first logic means responsive to said frequency of said signals from said first and second sources to produce a first intermediary signal having a pulse width representative of said phase angle difference between said frequencies; b. a first inverter circuit responsive to said first intermediary signal to generate an inverted first intermediary signal; c. a timing means responsive to said inverted first intermediary signal to generate a timing pulse having a pulse width representative of said predetermined value; d. a second inverter circuit, said second inverter circuit responsive to said timing pulse to generate an inverted timing pulse; e. second logic means responsive to said inverted timing pulse and said inverted first intermediary signal to produce a second intermediary signal whenever said pulse width of said inverted timing pulse is greater than said pulse width of said inverted first intermediary signal; f. third logic means responsive to said first intermediary signal and said timing pulse to generate a third intermediary signal whenever said pulse width of said first intermediary signal is greater than said pulse width of said timing pulse; and g. an angle discriminator storage cell, responsive to said second and said third intermediary signals to generate said phase angle signal whenever said pulse width of said first intermediary signal is less than said pulse width of said timing pulse.

Claim 18

The control system as recited in claim 7 wherein said frequency difference circuit comprises: a. first trigger means responsive to said phase angle signal to generate a read pulse; b. second trigger means responsive to said read pulse to generate a reset pulse; c. a first time delay means responsive to said reset pulse to produce first and second time delay signals; d. a second time delay means responsive to said reset pulse to produce third and fourth time delay signals; e. said first switch means responsive to said read pulse and said first time delay signal to produce said first difference signals whenever said difference in frequency between said signals from said first and said second sources is less than said first preselected value; f. said second switch means responsive to said read pulse and said third time delay signal to produce said second difference signal whenever said difference in frequency between said signals from said first and second sources is greater than said second preselected value; and g. said third switch means responsive to said read pulse, said second time delay signal and said fourth time delay signal to produce said third difference signal whenever said difference in frequency between said first and said second sources is greater than said first preselected value and less than said second preselected value.

Claim 19

The control system as recited in claim 12 wherein said first time delay signal has a polarity opposite that of said second time delay signal, and said third time delay signal has a polarity opposite that of said fourth time delay signal.

Claim 20

A frequency difference circuit for sensing a difference in frequency between signals from first and second alternating current sources, said circuit comprising: a. first trigger means responsive to a phase angle signal to generate a read pulse; b. second trigger means responsive to said read pulse to generate a reset pulse; c. a first time delay means responsive to said reset pulse to produce first and second time delay signals; d. a second time delay means responsive to said reset pulse to produce third and fourth time delay signals; e. a first switch means responsive to said read pulse and said first time delay signal to produce a first difference signal whenever said signals from said first and second sources is less than a first preselected value; f. a second switch means responsive to said read pulse and said third time delay signal to produce a second difference signal whenever said difference in frequency between said signals from said first and second sources is greater than a second preselected value; and g. a third switch means responsive to said read pulse, said second time delay signal and said fourth time delay signal to produce a third difference signal whenever said difference in frequency between said first and second sources is greater than said first preselected value and less than said second preselected value.

Claim 21

A frequency difference circuit for sensing a difference in frequency between signals from first and second alternating current sources, said circuit comprising: a. first trigger means responsive to a phase angle signal to generate a read pulse; b. second trigger means responsive to said read pulse to generate a reset pulse; c. a first time delay means responsive to said reset pulse to produce first and second time delay signals; d. a second time delay means responsive to said reset pulse to produce third and fourth time delay signals; e. a first switch means responsive to said read pulse and said first time delay signal to produce a first difference signal whenever said signals from said first and second sources is less than a first preselected value; f. a second switch means responsive to said read pulse and said third time delay signal to produce a second difference signal whenever said difference in frequency between said signals from said first and second sources is greater than a second preselected value; and g. a third switch means responsive to said read pulse, said second time delay signal and said fourth time delay signal to produce a third difference signal whenever said difference in frequency between said first and second sources is greater than said first preselected value and less than said second preselected value.

Claim 22

The control system as recited in claim 14 wherein said first time delay signal has a polarity opposite that of said second time delay signal, and said third time delay of signal has polarity opposite that of said fourth time delay signal.