Segregated phase comparison relaying apparatus

Claim 2

A breaker tripping system for a polyphase power transmission having an n number of phase conductors and an n number of breakers controlling the energization oF said phase conductors, said systems comprising an n number of phase conductor fault determining networks individually associated with said n phase conductors, each of said fault determining networks having an output terminal energized with a logical fault signal in response to the occurrence of a fault on the said phase conductor with which it is associated, a residual fault determining network associated with said line, said residual fault determining network having an output terminal energized with a logical fault signal in response to the occurrence of a residual fault on the said line, n number of AND networks, each said AND network having a plural number of inputs and an output, first circuit means individually connecting a first of said inputs of said n AND networks to said output terminal of said n phase conductor fault determining networks, second circuit means connecting a second of said inputs of said n AND networks to said output terminal of said residual fault determining network, and third circuit means individually connecting said output of said n AND networks to said n breakers, each said AND network being operable in response to the existence of a logical fault signal at both of its said inputs to provide a tripping signal at its said output terminal for its associated said breaker.

Claim 3

The system of claim 1 in which there is provided an n number of first timers and 9 second timers, said n first timers being included in said first circuit means, each said first timer being operable to delay for a first predetermined interval the transmissions of the said logical fault signal by the associated said first circuit means to the said first input of the AND network to which said associating said first circuit means is connected said second timer being including in said second circuit means and operable to delay for a second predetermined interval the transmissions of said logical fault signal of said residual fault determining network to said second inputs of said AND networks, said first intervals being of lesser duration than said second interval.

Claim 4

The system of claim 2 in which each of said fault determining networks includes comparing means for comparing the direction of the current flow at first and spaced locations along said power transmission line, said comparing means being effective to limit the time period that the said output terminal of the associated said fault determining network is energized with its said logical fault signal to the overlap time of the current at said spaced locations, said overlap time being the time that said current flow at said spaced location is in the same direction with respect to a location intermediate said spaced locations.

Claim 5

The system of claim 3 in which there is provided an n number of third timers and an n number of OR networks, each said OR network having first and second inputs and an output, each said third timer having an input and an output, said inputs of said n third timers being individually connected to said output terminals of said n fault determining networks and operable to delay for a third predetermined interval of the transmission of a logical signal to said first input of the said OR network with which it is associated, said outputs of said n third timers being individually connected to said first inputs of said n OR networks, said third circuit means individually including said second inputs and said outputs of said n OR networks.

Claim 6

The system of claim 4 in which the timing interval of said third timers is greater than the timing interval of said first timers.

Claim 7

The system of claim 4 in which the timing interval of said third timers is the same as the timing interval of said second timer.

Claim 8

A protective relaying system for a polyphase power transmission line having n number of first phase conductors individually connected to n number of second phase conductors through n number of circuit breakers; n + 1 nuMber of apparatuses; each of said n + 1 apparatuses comprising a local current sensing device having a local output quantity which has a characteristic which indicates the phase of the local current, a receiver for energization from a remote current energized device and providing a remote output quantity at its said associated said apparatus which has a characteristic indicating the phase of the remote current, a quantity comparing network having a pair of inputs and an output, a first timer having an input and an output, and a breaker tripping circuit having an input; each of said n apparatuses having a second timer and a local fault detector; said fault detector and said local current sensing device and said remote current energized device of said n apparatuses being energized in accordance with the operating characteristic of the said phase conductor with which the respective one of said n apparatuses is individually associated; each said quantity comparing network having its pair of inputs operatively connected to said local current sensing device and to said remote current energized device for comparison of said local and remote quantities and effective to provide an output signal at its said output which is a function of the phase relationship of said current at said local and remote terminals, each said apparatus having a first and a second circuit actuating network, each of said circuit actuating networks having an energizing input and an arming input and a breaker tripping output, each of said first circuit actuating networks having its said energizing input connected to said output of its associated said comparing network and its said arming input connected to its associated said fault detector, each of said n apparatuses having said inputs of its said first and second timers connected to said output of its said first circuit actuating network and effective to time out upon energization of its associated said breaker tripping output, the remaining one of said n + 1 apparatuses having its said current sensing device and its said receiver energized by the local and remote residual current flowing in said transmission line and having said input of its said first timer connected to said output of its said first circuit actuating network and effective to time out upon energization of its associated said breaker tripping output, said output of said first timer of said remaining one of said n + 1 apparatuses being connected to said arming inputs of each of said second circuit actuating networks, each said second circuit actuating network having its said energizing input connected to said output of the said second timer with which such said second switching network is associated, said breaker tripping circuit of each of said n apparatuses being connected to said output of its associated said second switching network and of its associated said first timer.

Claim 9

A protective relaying system for a polyphase power transmission line having n number of first phase conductors individually connected to n number of second phase conductors through n number of circuit breakers; n + 1 nuMber of apparatuses; each of said n + 1 apparatuses comprising a local current sensing device having a local output quantity which has a characteristic which indicates the phase of the local current, a receiver for energization from a remote current energized device and providing a remote output quantity at its said associated said apparatus which has a characteristic indicating the phase of the remote current, a quantity comparing network having a pair of inputs and an output, a first timer having an input and an output, and a breaker tripping circuit having an input; each of said n apparatuses having a second timer and a local fault detector; said fault detector and said local current sensing device and said remote current energized device of said n apparatuses being energized in accordance with the operating characteristic of the said phase conductor with which the respective one of said n apparatuses is individually associated; each said quantity comparing network having its pair of inputs operatively connected to said local current sensing device and to said remote current energized device for comparison of said local and remote quantities and effective to provide an output signal at its said output which is a function of the phase relationship of said current at said local and remote terminals, each said apparatus having a first and a second circuit actuating network, each of said circuit actuating networks having an energizing input and an arming input and a breaker tripping output, each of said first circuit actuating networks having its said energizing input connected to said output of its associated said comparing network and its said arming input connected to its associated said fault detector, each of said n apparatuses having said inputs of its said first and second timers connected to said output of its said first circuit actuating network and effective to time out upon energization of its associated said breaker tripping output, the remaining one of said n + 1 apparatuses having its said current sensing device and its said receiver energized by the local and remote residual current flowing in said transmission line and having said input of its said first timer connected to said output of its said first circuit actuating network and effective to time out upon energization of its associated said breaker tripping output, said output of said first timer of said remaining one of said n + 1 apparatuses being connected to said arming inputs of each of said second circuit actuating networks, each said second circuit actuating network having its said energizing input connected to said output of the said second timer with which such said second switching network is associated, said breaker tripping circuit of each of said n apparatuses being connected to said output of its associated said second switching network and of its associated said first timer.

Claim 10

The combination of claim 7 in which said circuit actuating networks are AND networks.

Claim 11

The combination of claim 7 in which there is provided an ANY-2-OR network having n number of inputs and an output, said n inputs of said ANY-2-OR network being individually connected to said outputs of said first timers of said n apparatuses, said output of said ANY-2-OR network being connected to each of said breaker tripping circuits of said n apparatuses.

Claim 12

The combination of claim 9 in which said fault detectors each respond to the occurrence of above a predetermined magnitude to apply an arming signal to the said arming input to which it is connected, each of said local current sensing devices and of said remote energized device including current squaring devices whereby said characteristics of said output quantities are square waves having half cycle duration substantially equal to the half cycle durations of the current in said phase conductors.

Claim 13

In a protective relaying system for protecting a polyphase transmission line having a line cOnductor for each of said phases, said system comprising an apparatus for each of said phases; each said apparatus including a plurality of AND networks, a plurality of timers, a fault detector, a receiver, a signal phase comparing network, said receiver having a first output connected to first input terminals of first and second of said AND networks, for supplying signals thereto, said receiver being effective when receiving a signal indicative of the reception of a fault responsive signal to supply operating signals to each of said just-named first input terminals and to energize a first input terminal of said phase comparing network with a signal which is representative of the remote line operating characteristic being transmitted to said receiver, means connected to a second of said input terminals of said phase comparing network and effective to energize said just mentioned second input terminal with a signal which is representative of the local line operating characteristic said fault detector being individually associated with the said phase conductor with which its said apparatus is associated and effective to provide a current signal which is proportional to the magnitude of the current in the said phase conductor with which it is associated, said fault detector having an output terminal connected to second input terminals of said first and said second AND networks and effective to provide an operating signal to said just-named second input terminals solely when said fault detector is responding to a fault condition, a first of said timers having an input connected to said receiver and an output connected to a third input terminal of said first and second AND networks, said timer being effective in the absence of an output signal from said receiver to time out a time interval and to thereafter supply a non-operating signal to said just-named third input terminals, a second of said timers having an input connected to said output of said first AND network, a third of said timers having an input connected to said output of said second AND network, said first and said second AND networks being effective to provide an operating signal to the said one of said timers associated therewith solely when all of its said input terminals are energized with an operating signal, a breaker operating network, each of said second and said third timers being effective when timed out to actuate said breaker operating network, phase current interrupting circuit breaker individually associated with each of said phase conductors, each said breaker operating network being individually associated with the one of said breakers which is associated with the one of said phase conductors with which its said apparatus is associated and being effective when actuated to trip individually the said breaker with which such breaker operating network is associated, each said first apparatus further including a fourth of said timers and a third of said AND networks, each said AND network having a plurality of inputs and an output, said fourth timer having its input connected to said output of said first AND network and its said output connected to a first input of said third AND network, a residual current detecting means connected to each of said fault detectors and effective to provide a residual current output which is proportional to the magnitude of the unbalance in the phase conductor current, a fifth timer having an input connected to said residual current detecting means and an output connected to a second terminal of each of said third AND networks, each of said third AND networks having its said output connected to actuate the said breaker operating network of the said apparatus with which said AND network is associated, each said fourth timer having a lesser time interval than the said second timer associated with the same said apparatus.

Claim 14

In a protective relaying system for protecting a polyphase transmission line having a line cOnductor for each of said phases, said system comprising an apparatus for each of said phases; each said apparatus including a plurality of AND networks, a plurality of timers, a fault detector, a receiver, a signal phase comparing network, said receiver having a first output connected to first input terminals of first and second of said AND networks, for supplying signals thereto, said receiver being effective when receiving a signal indicative of the reception of a fault responsive signal to supply operating signals to each of said just-named first input terminals and to energize a first input terminal of said phase comparing network with a signal which is representative of the remote line operating characteristic being transmitted to said receiver, means connected to a second of said input terminals of said phase comparing network and effective to energize said just mentioned second input terminal with a signal which is representative of the local line operating characteristic said fault detector being individually associated with the said phase conductor with which its said apparatus is associated and effective to provide a current signal which is proportional to the magnitude of the current in the said phase conductor with which it is associated, said fault detector having an output terminal connected to second input terminals of said first and said second AND networks and effective to provide an operating signal to said just-named second input terminals solely when said fault detector is responding to a fault condition, a first of said timers having an input connected to said receiver and an output connected to a third input terminal of said first and second AND networks, said timer being effective in the absence of an output signal from said receiver to time out a time interval and to thereafter supply a non-operating signal to said just-named third input terminals, a second of said timers having an input connected to said output of said first AND network, a third of said timers having an input connected to said output of said second AND network, said first and said second AND networks being effective to provide an operating signal to the said one of said timers associated therewith solely when all of its said input terminals are energized with an operating signal, a breaker operating network, each of said second and said third timers being effective when timed out to actuate said breaker operating network, phase current interrupting circuit breaker individually associated with each of said phase conductors, each said breaker operating network being individually associated with the one of said breakers which is associated with the one of said phase conductors with which its said apparatus is associated and being effective when actuated to trip individually the said breaker with which such breaker operating network is associated, each said first apparatus further including a fourth of said timers and a third of said AND networks, each said AND network having a plurality of inputs and an output, said fourth timer having its input connected to said output of said first AND network and its said output connected to a first input of said third AND network, a residual current detecting means connected to each of said fault detectors and effective to provide a residual current output which is proportional to the magnitude of the unbalance in the phase conductor current, a fifth timer having an input connected to said residual current detecting means and an output connected to a second terminal of each of said third AND networks, each of said third AND networks having its said output connected to actuate the said breaker operating network of the said apparatus with which said AND network is associated, each said fourth timer having a lesser time interval than the said second timer associated with the same said apparatus.

Claim 15

The combination of claim 11 in which each said second timer has a lesser time interval than the said third timer associated with tHe same said apparatus.

Claim 16

The combination of claim 11 in which there is provided an ANY-2-OR network, having a plurality of inputs and an output, said ANY-2-OR network being characterized by the fact that its said output is actuated solely when two or more of its said inputs are actuated, means individually connecting said inputs of said ANY-2-OR network to said outputs of said second timers, and means operatively connecting said output of said ANY-2-OR network to each of said breaker for actuation thereof when said second timers of any two of said aparatuses time out.