close

Вход

Забыли?

вход по аккаунту

?

Патент USA US2406411

код для вставки
A118. 27» 1945»
w.A K. soNNEMANN
2,406,411
UNIVERSAL SEQUENCE‘CURRENT RELAYING MEANS
Find am. 21. 1944
a
Í
if.
"?
à.;
__
___
'wf
-.._
Q-o
Ja
'
Í 7)
7M á ¿ML
ATTGRNEY
Patented Aug. 27, 1946
2,406,411
UNITED STATES PATENT GFFICE
2,406,411
UNIVERSAL SEQUENCE-CURRENT
,
RELAYING MEANS
William K. Sonnemann, Roselle Park, N. J., as
sìgnor to Westinghouse Electric Corporation,
East Pittsburgh, Pa., a corporation of Pennsyl
vania
Application January 21, 1944, Serial No. 519,145
21 Claims. (Cl. 175-294)
l
2
My invention relates to protective relaying de
vices for detecting faults in polyphase lines such
as transmission-lines, and it has particular rela
an approximately vconstant magnitude, which
contributes considerable to the non-selectivityof
the device, when subjected to faults on different
phases, as described. This “HCB" relaying-sys
tem is described in a Harder Patent 2,183,646 of
december 19, 1939, which is assigned to the West
inghouse Electric 8a Manufacturing Company,
tion to a universal relaying-’element which is re
sponsive to phase-sequence' current-components
which are compounded in a special way whereby
the single relaying element is responsive with fair
ly comparable sensitivity to all possible diiferent
kinds of fault which may occur in a polyphase
It is an object of my present invention to pro
vide an improvement over the Harder “HCB” re
line, without being affected by which single phase
laying system, in which I avoid the utilization of
I is faulted to ground or which two of the three
phases are involved in a double phase-to-ground `
the vectorial sum of a positive-sequence current
component and a zero-sequence current-com
fault. In short, my relaying apparatus does not
ponent, which could conceivably total zero if the
two components happened to be exactly equal to
My derived phase-sequence current-responsive 15 each other and exactly 180° out of phase with each
quantity may be utilized directly for the energi
other.
have a “blind spot.”
zation of a single relaying-element, or it may be
_ utilized in conjunction with piiot wires or other
It is an object of my invention to utilize a re
sponse to only `the positive-sequence current com
form of a communicating-channel for comparing
ponent, and to supervise or alter the responsive
similarly derived voltages or currents from the 20 ness tolthis component, in, accordance with the
two ends of a protected three-phase line-section.
magnitude, but not the phase, of the zero-se
quence current-component, or the negative-se
Heretofore, two diiîerent types of universal se
quence-current relaying-devices have been in gen
quence current-component, or both the zero-se
eral use, and both have been subject to the possi
quence and the negative-sequence current-com
bility, or the suspected possibility, that they may 25 ponents. In this way, I provide a relay which can
have “blind spots,” or conditions of dangerously
~ have the same sensitivity to all different kinds or
reduced sensitivity to certain very special fault
locations or magnitudes of fault, or any desired
relative degrees of sensitivity to different kinds
conditions, of one kind or another, depending
upon the phase-relationships between the zero
of faults, in a relaying system which has no “blind
sequence current component and the positive-se 30 spot” and which is not at all affected by the par
quence current-component, or between all three
ticular phase which happens to be faulted.
of the current-components, depending upon which
With the foregoing and other objects in view,
single phase is faulted in a double phase-to
my invention consists in the systems, circuits,
ground fault. In one of these previously known
combinations, elements, apparatus, and methods,
systems, the line-currents from all three of the 35 hereinafter described and claimed, and illustrated
line-conductors are combined in a special trans
in the accompanying drawing, the single iigure of
former which produces a single-phase current
which is a diagrammatic view of circuits and ap
which is supposed to be more or less reliably re
paratus illustrating my invention in a preferred
sponsive to any possible kind of fault.
form of embodiment.
In the other previously known universal-fault 40 In the drawing, I have illustrated the invention
current-deriving system, the positive and zero
as being applied to the protection or a line-section
phase-sequence components of the line-currents
l which is a part of a three-phase transmission
have been vectorially added, in a phase-sequence
system, the protected line-section I being con
network known as an “HCB” network, in which it
nected between ‘buses 2 and 2’ at two diiîerent sta
is believed that a somewhat better single-phase 45 tions. Since the equipment at each line-terminal
relaying quantity is derived, so as to be responsive
or station is identical, and symmetrically disposed
to any possible kind of fault, but still having a
with respect to the center of the protected line
certain amount of variation in the responsive
section I, I shall largely confine my explanation
ness, according to the variations in the phase
and descriptionv to the equipment at the terminal
angles between the positive and zero phase-se 50 represented by the three-phase bus 2, the corre
quence components, which is to say, according to
sponding equipment at the other terminal being
which phase is faulted, and what kind of fault it
distinguished by primed letters or numerals, as in
is. This “HCB” relaying system also makes use
the case of the bus 2'.
`
of a current or voltage-limiting means for pro
The equipment at each station, such as the
ducing a substantially sinusoidal output-wave of 55 left-hand station, in the illustrated form ‘of em
2,406,411
bodirr'ient ofthe invention, includes a three-phase
line-segregating circuit-interrupting means, such
energy to the trip-coil TC, through the auxiliary
as a circuit-breaker 3, which has an auxiliary
make-switch 3a, and a trip-coi1 TC. The equip
ment also includes a bank of three-phase line 5
pole circuit-interrupting operation of the break~
breaker-switch 3a, so as Vto produce a three
current transformers which supply energy toa
The energiz‘ation of the relay., I2, in the illus
fforinofembodirhent of '_theïinvention, is
phase-s'ëúuéncjeijfn i pri; orl'netwíor ì ‘Shaving
output-ltërmhials‘q Ir"
er 3, in the illustrated form of embodiment of
the invention.
" tratie
which the?e'f" appears --a
'th’eïsa?neï as described and claimed in the Harder
single-phase current or voltage which is selective- _
patent. The relay is provided with a strong op
1y responsive solely to the positive-sequence coin-“ f’ferating-coil O, and a weaker restraining-coil R,
ponent of the line-current. Theparticular nete; v_. which isillustrated as being adjustable. Since
work 5 which is shown in the figure also-,basa
the relay is a polarized relay, the operating and
restraining windings O and R must be energized
second pair of terminals I2 in which there appears
a single-phase current or voltageljwhljch "isz-selec?` '- with/'unidirectional currents, which are illus
tively responsive solely to,thejnegative¿sequence` l5” trate'd‘ -as being obtained through rectifier
component of the line-current?"
The positive-sequence output I1 of the current
' "bridges, or other full-wave rectiñers, B1 and B2,
respectively. The bridge B1 which energizes the
operatingcoil O'is energized across the terminals
of the insulating transformer ID, while the bridge
to energize an adjustable saturating transformer 20 B2," which supplies the restraint-winding R, is
6, which produces peaked wave-forms of more or
serially connected in series with the lead 8.„ or
.til‘essflimitedmagnitude;V the peaks "of which are
-betw'een the lead 8 and the insulating'transform
responslve phase-sequenceiietWorkf-'S is'futilized,`
in the manner described in the Harder patent,A ,I
"i removed` .by La». glow-lamp- 'fI ‘0r- I'similar ' Lmeans,
er IIJ:
'wherebysla fairly ¿sinusoidal "‘wave‘lrfo'rm’i's ob'
The‘system' so far describedv in detailv is the
v- tained ‘in ’ the relayingfßcircuit which is- :provided
sameras one of the forms of embodiment‘which
zrby.-the-"outputlterminals1B fand' 9 lof the device,
i-asïexplainedi’ in theV Harder,v patent, except that I
are illustrated inthe Harder patent, except that
the saturating"transformer- 6 isenergized re
utilize Vauresp'onse Ptolemy-‘the - positive-sequence
»sponsively to=only`the positive-sequence current,
component, 'i rathersthan -a ¿response îto 'both the
rather than the vectorial- sum of the positive and
30
>gizing'thesaturating transformerJB. v " y
-
¿
».
_
invention; `.the output: of the vsnetwork-term‘in'als
`8,.:and `9 v¿isv> applied: to :anzinsulatingï ‘transformer
f the;` particular 'pilot-wire" system - 'which' - is illus
trated - being of 'the well-'known . current-circulat
othempilot-wire systems may-'be- utilized,V as »will
ybe understood -iby the `skilled workers'of the' art.
v
of> faults-on the protected line-section I ,‘ but the
>Illnvvhichìfisf connected-‘to oney end of'fa pair of
Vpilot-‘wiresdI"which zextend to ysimilar equipment ,«
at the far end of the protected line-section I,
no fault on the »protected »line-section TI“, although «
'
.. There will, of course, be positive-‘sequence com
ponents present in'all possible kinds or'degrees
- -vfIrrithe‘ß'illustrated?form -of embodiment` of vthe
ing.- type,fwhìch circulates-current when there is
zero- sequence components.
40
lpositive-sequence component cannot, in general,
be utilized, alone, as a fault-detector, even with
,the aid of the. so-calle'd constant-magnitude'de
vices 6 and 'I,‘ because‘the-magnitude of the pos*
itive-sequence componentV of the‘fault-current,
-forcsingle -ground-faults, for example, may be
considerably less than theïb'alanced power-'cur'
vrents of the line underf'normal 'fault-free opera
tion.- It is-an essential feature of. my present in
vention, therefore, that the sensitivity or >re
Any suitablemeans may 'be> utilized for >re
sponse-proportionality of the response‘to the pos
sponding-:to- thefcurrentpr voltage which ap 45 itive-sequence current-component is increased,
»pears inthe'network-terminals 8 and >9, and this
or monitored, by the zero-sequence current-com
.response may be eithera simple overcurrent or
ponent, or by the :negative-sequence current
sovervoltage response to thev current or- voltage in
. component, or both;
, _thep‘terrninals sand 9 alone, orv it maybe a com
Referring to` the drawing, it win be noted that
¿parative -response-of any-sort',> which takes into 50 thel sensitivity of the'positive-sequence response
.consideration aV comparison Aof the output- of‘the
,is‘reduced by drawing off energy through a vari
terminals- ßgand .9 _atene station, .as 4compared
4_able resistoriARxy, which is connected‘across the
»with «the output of Vthe 'corresponding-terminals
_network-terminals B and 9 through a rectifier
«,8’. and 9’ atathe other station,fsaidr` comparison
bridge B3, or-other full-wave rectifier, which sup
being eiîectedthrough the'fpilot-wires II, or any 55 plies,unidirectional-current energy to -'the posi
equivalent-._y communicating-channel means - ex'-- tive andnegative terminals R+ and R-'of the
tending from another'line-,terminal
»
resistor Rxy. 1n general,` it is desirable to sup
¿The particular.. embodiment .of lmyninventio'n
press the ripples in »the rectified-current output
v which is illustrated in thexdrawing utilizes a. ra
circuit of the bridge B3, which may be accom
tio-differential protective relay I2, .which is illus' 60 plished by any suitable means, such as a shunt
connected capacitor I6. „ ,
"
»trated asffav polarizedmelay havingß’a` polarized
movable` armature I3, `the polarization of 4which
In the illustrated form of embodiment of my
is indicated >bythe letters `N and'S representing
inventioml provide an adjustable transformer
northand south poles, respectively. Aipolarized
I'I, which may or mayl not be saturable, which
vform of differential relayA I2 is shown, for the sake
>is energized from the residual-currentfcircuit of
the fline-current transformers 4, so asfto be re
Loffthe greater'sensltivity and-the lower burden
sponsive to the zero-sequence current-component,
>which.is¿obtainable in thistype of relay, but; the
vinventionis obviously not limited to any particu“
and this transformer `I‘I -is utilizedto energize a
lartype, of relayufuIny order to prevent the relay
rectifier-bridge B4 which also supplies current,
.from respondingtoonuicklyso that‘it would re
in the samepolarìty as the bridge B'gfto >the ter
spond-:to thepulsations-or ripples ofl its’ ener- ' ` minals R+ and R--of the resistor'Rxy,- the same
,gizatiomgitmay be provided» with ’a’lagi-ring' I4,
‘capacitor'lûserving to- absorbv the ripples of the
as willv be well understood. AThe movable element
I3 of the differential relay IZV-is'iutilizedto con
rectified-current output of the’bridge B4.
"
In the illustrated form of embodiment of my
vtrola trip-circuit" I5Y which suppliestripping 7,5 invention, I also provide another adjustable trans
2,406,41;
5
,
positive-sequence network-terminals 8 and 49, by
former I8, which also Ímay or may not be sat
‘urable,f.which is energized=from the negative-se.
>the bridgerBaI-tdbeireduced in proportionto the
amount of energy fwhich isfsupplied to the -re
quence terminals ‘Iz-of the current-responsive‘se
-sistor-'Rxy by the bridge B4, until, inathe limiting
-quence-network 5. “The'transforrner lß'energizes
4case,- no energy at all-is Withdrawn from the posi
a rectifier-bridge B5, the output-terminals :of
which are connected to the resistor-terminals R+ r “tive-sequence network-terminals v8 and;.9_by-the
and R+, inthe same polarity as the outputs of
The zero-sequence-responsive bridge B4 may be
the bridges B3
and.B4.»
3
.
»
,
Y
l
v
,v
Y
In operation, >`during` normar power-transmit
10
ting conditions when there is ‘a balanced three
utilized Valone',iwithout the negatiVe-sequence-re
=sponsive l'bridge B5, to -monitorffthe Apositive-se
queme-'responsive'terminals A8 and 9, soas to »in
crease the-sensitivity of. the positive-sequencere
phase load on the transmission-line, ‘butv no fault ‘ '
thereon‘, ‘there will`VÃL be no Vzero-seduencercurrent
,-sponse --iniaccordance with .the amount of zero
component and 'no negative-sequencer'current
seqùence current-'component Which-is present in
-the fault-current, up until the point-‘of maximum
component, so that the network-'terminals >8 and
Y9 will feed a vconsiderable amount of energy into
the resistor Rxy, none of this energy going-through -
sensitivity» isereached,` when no 4current Vis .with
the bridges B4 and B5, which'a'reconnec'ted in
such 'polarity that current cannotflow from the
resistor-terminals R+ >and R- int() said bridges,
- drawn » from ' the' network-terminals 8-.f9 by the
>resistor R'Xy. -Since thefzero-sequence current
¿component is not present at all, except .under
except for very'small leakage-currents which may _ Afault-conditions, the zero-sequence response can
be assumed to be negligible, so far'as our present l» be madelextremely sensitive’vbeing limited»- only
by the `necessity rfor~ avoiding a deleterious re
considerations -`are concerned." The resistor> Rxy
sponse- to the spurious zero-sequence components
is chosen so as to’h-'ave' such a'mag'nitucie,` in com
which vare sometimes produced by faulty-match
parison with ' the serially connected positive-sè
ing-#of-V the line-current- transformers `4. :In this
quence-circuitimpedances of the network 5--6--1
and the bridge B3, ythat't'he sensitivity' 'of response-wv. manner, thel relay I2> can have a high sensitivity
-tov all faults lhaving* any» zero-sequencey current
to the positive-sequence currents~ maybe reduced
components, so' that the ability of the relay vI2 to
to any desired level 'or value.
"
' `
'
’
‘
respond to ground-faults can be madel to' match
`When a- three-phase'fault occurs on- the pro
tected line-section, fa very- large positive-sequence 30 its ability Eto respondft'o faults >which’ have no
current-component is present inthe line-current,- î izero-se'quence componenti
There are -only'two kinds of Afault which have
and the sensitivity of responseis adjusted so that
no ¿zero-sequence;ïcomponentj namely, asolid
the relay I2 will have thedesired amount oïf re
three-phase fault 'involving no- ground, in which
'sponsivity to the positive-sequence component
4under this fault-condition.
'_ ’
'
'y ’v
»
i 'case »the fault-currents are extremely! heavy, and
`
the minimum positive-sequence sensitivity is de
sirable,'an'd phase-to-phase faults involving only
*two vof ‘the 'line-conductors; butv no ground, in
:which case the positive-sequence component is
578%’a's great as with a'three-phase'fa'ult, for the
saine fault-amperes, which is ystill generally vamply
If a single line-to-g'röund fault should occur,>v
the positive-sequence component of I the fault
ourrent may be so small that the component which
appears in the' network-terminals 8-9 may> be
no more than is'neces’sary to produce theÍ required
responsivity inthe ‘relay ï'I2, even thoughjno ~
energy is withdrawn'from thet'er'rninals 8-y9rbry
Íïsuiiicientlto venable the relay >I2 to respond easily
the resistor Rxy. This -condition, whereby Vthe
network-terminals 8 and 9 lsupply no energy to
-the resistor Rxy; or any intermediate condition,
of» beingy oVe'rbui‘dened-on’the more severe fault.
' tofboth of these types'of fault, without danger
'- It is fp'ossible, however',1 and sometimes desir
able', to utilize afnè'gative-sequence monitoring,
as in the case of a >double line-to-'grourid fault,
instead of, 0r in addition to, the zero-sequence
is brought about by the zero-sequence-responsive
' monitoringfwhich'h'a's just -been described. -The
’i negative-sequence response usually entails the use
bridge B4, which maintains, across the À'resistor
terminalsv R+ and R+, a potential which isy re
of a; networkV which imposes amgreater burden
sponsive to the magnitude of the zero-sequence 50 normally
upon the current-'transformers 4 than
component, reduced by the serially connected im
the 'network which delivers thefzero-sequence re
pedances of the zero-seduence-energized`trans
s'ponse,` which do'es‘no't normally entail “any bur
former I‘I and bridge B4, withsuiiicient sensitivity "denjbut'` itv hasy 'certain advantages', in that'the
of response so that the rectiiied zero-sequence
' negative-sequencel
responsive Voltage, put out by the` bridge B4, may
be equal to the rectified voltage which ,is put
out by the bridge Badwith a reduced current-,flow
from the circuit ß-ïjthrough the bridge B3,
to the terminals R+ arid R+; th'atfisywitha
reduced voltage-drop in' the' eifectiye positive
not
vrconditions',y when there is no fault- on the >trans
mission system, but'it >_is present in all possible
kinds of fault, including the phase-to-p'hase fault
60
`sequence-circuit impedance _of theelementsñ, .6, '
-I and B3. Therectiñed Voltage of B4 may even
be larger than that of Bs, in which case B4 does
not feed energy back into theiterminals 8 and 9
through the bridge B3, because the VAp'îolarity of
therectiñers of the bridge n, B3 is 4directed "the Ä
wrong way for such energy-transfer, and the re
current-component 'is
present,> at all, ‘under normal _power-transmitting
'as Wella as ‘the single-phase ground-fault, except
'a balancedr three-phase fault. "
'- It isf possible, therefore, to utilize a very sensi
tive response to _the negative-sequence current
vcomponent,- from'the terminals I2, to energize the
rectifier-bridge' Bs,` so '_as to" produce‘a rectified
voltage, which is applied to the lresistor-terminals
R+ and Rl-, which' bears any desired vrelation to
the corresponding positive-sequence-responsive
sult is Simply that _no’energy is Withdrawn from
rectiñed Voltage lof the bridge B3, under lany vde
the terminalsY B and 9 by the-bridge B3 under Asuch 70 -s'i'red conditions, Ithe operation being similar to
conditions.
._
`
I
l
'
`
' 'that which has already been describedinîconnec
In either event, the effect of. thezero-sequence- ' l ’ tion "with monitoring by the zero-sequence re
energized bridge B4, in parallel to the positive
.» As' previously intimated, both of the monitor
sequence-energized bridge B3, is to cause the
y amount of energy which is withdrawn from the 75 4ing bridges 'B4 and B5 can be utilized together, in
2,406,411
7
8
which case, whichever voltage-response is the
greater, will take control, and control the recti
and 9. I desire, therefore, that the appended
fied voltage which appears across the resistor
claims shall be accorded the broadest construc
tion consistent with their language and the prior
terminals R+ and R-, since no energy can be
art.
fed back, in the reverse direction, into any one
'
I claim as my invention:
of the parallel-connected bridges Ba, B4, and B5,
1. In a relaying system for protecting a poly
phase line, means for providing a relaying circuit
carrying a single-phase electrical quantity which
is responsive to the positive-sequence component
of the line-current, means for energizing a resis
tor from said relaying circuit through a full
the output-terminals of which are connected in
parallel across the resistor-buses R+> and R-. .
It will be observed that, in a way, my present
system is an application of the “largest-phase”
relaying-system which is shown in the Harder
Patent 2,242,950, of May 20, 1941, assigned to the
Westinghouse Electric & Manufacturing Com
wave rectifier, means vfor deriving another se
quence component of the line-current, means f
pany. Harder there utilized a similar parallel
for energizing the same resistor from said other
bridge system for obtaining a response to which 15 sequence component through another full-wave
ever phase was the largest, whether the phase-A
rectifier in the same polarity as the first-men
current, or the phase-B current, or the phase-C
tioned energization, and relaying means having
current, or the residual current times any desired
an energization yfrom said relaying circuit.
multiplying-constant. In my present relaying
2. In a relaying system for'protecting a poly
system, however, I do not determine the largest
phase line, means for providing a relaying circuit
carrying a single-phase electrical quantity which
is responsive to the positive-sequence component
phase, but, in a way, I determine the largest
phase-sequence component (with suitable multi
plying-factors), comparing the magnitudes, but
of the line-current, means for energizing a resis
tor from said relaying circuit through a full-wave
ponents which are applied to the input-terminals 25 rectifier, means for deriving another sequence
of- the several parallel-connected rectifier-bridges
component of the line-current, means for ener
B3, B4, and B5, or as many of said 'bridges as may
gizingthe same resistor from said other sequence
be utilized.
component through another full-wave rectifler
It will be observed that the sensitivity of the
in the same polarity- as the first-mentioned ener
response to the positive-sequence component, as A30 gization, communicating-channel means adapted
monitored by the zero-sequence or the negative
to compare said single-phase electrical quantity
sequence components, or both, as obtained in my
with a quantity similarly provided at another
not the phase-relationships, of the several com
present system, is not at all affected by the phase
point in the line, and relaying means having
relationships between alternating currents or
energization from both said relaying circuit and
voltages which represent these various phase 35 said communicating channel.
sequence components. 'I'his is particularly true
3'. In a relaying system for protecting a poly
when some sort of ripple-suppressor, such as the
capacitor I6 or any equivalent device, is utilized
for substantially suppressing or withdrawing the
ripples from the rectified-voltage outputs of the 40
various parallel-connected bridges B3, B4, and B5.
In this manner, I obtain,.in a single device, a
response with any desired uniformity of sensitiv
ity, to all kinds of faults, without any “blind
spots” and without being affected by which phase
the fault is on.
'
It will be understood that the magnitude-con
trol elements 6 and 1, which were carried over
from the Harder “HCB" system, may, or may not,
be utilized. 'I'his feature is useful in reducing
the effect of differences in the severity of the
fault, particularly the severity of a three-phase
fault, but my explanation of the invention has
been given on the basis of properly increasing the
sensitivity of the positive-sequence response in
accordance with the monitoring zero-sequence or
negative-sequence components, or both, without
reference to the presence or absence of the mag
phase line, means for deriving the positive-se
quence component of the line-current, magni
tude-limiting means for providing a relaying cir
cuit having a single-phase electrical quantity
which is responsive to said positive-sequence com
ponent, means for energizing a resistor from said
relaying circuit through a full-wave rectifier,
means for deriving another sequence component
45 of the line-current, means for energizing the same
resistor from said other sequence component
through another full-wave rectifier in the same
polarity as the first-mentioned energization, and
relaying means having an energization from said
relaying circuit.
4. In a relaying system for protecting a poly
phase line, means for deriving the positive-se
quence component of the line-current, magni
tude-limiting means for providing a relaying cir
cuit having a single-phase electrical quantity
which is responsive to said positive-sequence
component, means for energizing a resistor from
said relaying circuit through a full-wave rectifier,
means for deriving another sequence component
of the line-current, means for energizing the
same resistor from said other sequence component
through another full-wave rectifier in the same
lpolarity as the first-mentioned energization, com
municating-channel means adapted to compare
said single-phase electrical quantity with a quan
tity similarly provided at another point in the
nitude-limiting feature 6--1. It will be under
stood that, even when the magnitude-limiting
feature 6--1 is utilizedl my monitoring-combina
tion may be effective, even at voltages before the
saturating effect of the transformer 6 begins to
be felt, so that the output-circuit B--S may be
monitored, even though the positive-sequence
component is not large enough to saturate the
transformer 6.
line, and relaying means having energization
It will further be observed that, while I have
from both said relaying circuit and `said com
illustrated a particular kind of pilot-wire system,
municating channel.
and a particular kind of differential relay I2, my 70
5, The invention as defined in claim 1, char
invention is not limited to either one of these
acterized by said other sequence component being
details, as it is applicable, generally, to any device
the zero-sequence component.
which may be connected in any manner whatso
ever, so as to be energized, at least in part, in
response to the monitored network-terminals 8
6. The invention as defined in claim 2, char
acterized by said other sequence component being
the zero-sequence component.
2,406,411
7. The invention as deñned in claim 3, charac
terized by said other sequence component being
the zero-sequence component.
8. The invention as defined in claim 4, charac
terized by said other sequence component being
the zero-sequence component.
9. The invention as defined in claim 1, charac
terized by said other sequence component being
the negative-sequence component.
l0. The invention as deñned in claim 2, char
acterized by said other sequence component be
ing the negative-sequence component.
11. The invention as deñned in claim 3, char
acterized by said other sequence component be
19. In a relaying system for protecting a poly
phase liney phase-sequence means for developing
a single-phase control-voltage in a relay-circuit
in response to a phase-sequence function of the
line-current at the relaying station, fault-detector
means for selectively responding to line-current
conditions other than balanced positive-sequence
currents at the relaying station, means for utiliz
ing said fault-detector means for at times in
creasing the response-proportionality of said
single-phase control-voltage which is developed in
ing the negative-sequence component.
12. The invention as defined in claim 4, char
acterized by said other sequence component be
ing the negative-sequence component.
13. The invention as deiined in claim 1, char
acterized by said relaying system having two such
said relay-circuit in response to said phase-se
other-sequence deriving-means and energizing
quence function of the line-current at the relay
ing station, and relaying means having an ener
means, one involving the zero-sequence compo
nent and the other involving the negative-se
gization from said relay-circuit.
20. In a relaying system for protecting a poly
phase line, phase-sequence means for developing
a single-phase control-voltage in a relay-circuit
quence component of the line-current,
14. The invention as deñned in claim 2, char
acterized by said relaying system having two such
other-sequence deriving-means and energizing
in response to a phase-sequence function of the
means, one involving the zero-sequence com
line-current at the relaying station, fault-de
ponent and the other involving the negative-se
quence component of the line-current.
15. The invention as defined in claim 3, char
tector means for selectively responding to line
current conditions other than balanced positive
sequence currents at the relaying station, means
for utilizing said fault-detector means for at
acterized by said relaying System having two such
other-sequence deriving-means and energizing
times increasing the response-proportionality of
said single-phase control-voltage which is devel
means, one involving the zero-sequence compo`
nent and the other involving the negative-se
oped in said relay-circuit in response to said
quence component of the line-current.
phase-sequence function of the line-current at
the relaying station, communicating-channel
means for comparing the single-phase control
voltage of said relay-circuit with the control-volt
16. The invention as defined in claim 4, char
acterized by said relaying system having two such
other-sequence deriving-means and energizing
means. one involving the zero-sequence compo
nent and the other involving the negative-se
quence component of the line-current.
17. In a relaying system for protecting a poly
phase line, phase-sequence means for developing
two diiïerent single-phase control-voltages, in two
different relay-circuits, in response to two diiîer
ent phase-sequence functions of the line-current
at the relaying station, relaying means having an
10
control-voltage of a relay-circuit similarly pró
vided at another point in the line, relaying means
having energization from both said communicat
ing-channel and said relay-circuit at said relay
ing station, a direct-current load-device, and two
separate rectifier-means for respectively energiz
ing said direct-current load-device from said two
relay-circuits at the relaying station.
age of a relay-circuit similarly provided at an
other point in the line, and relaying means hav
ing energization from both said communicating
channel and said relay-circuit at said relaying
station.
45
energization from one of said relay-circuits, a di
rect-current load-device, and two separate rec
tiñer-means for respectively energizing said di- ì
21. Multi-responsive
fault-detector means,
adapted to be responsive to a plurality of diñîerent
kinds and phases of ground- and phase-faults on
a three-phase line, comprising current-responsive
voltage-developing means operative to develop a
voltage which is responsive, to a function of the
rect-current load-device from said two relay-cir
cuits at the relaying station.
18. In a relaying system for protecting a poly
three-phase line-current, means responsive to
said developed voltage, ground-fault detector
means for selectively responding to ground-fault
phase line, phase-sequence means for developing
two different single-phase control-voltages, in two
different relay-circuits, in response to two differ
ent phase-sequence functions of the line-current
at the relaying station, communication-channel
means for` comparing the single-phase control
rent-responsive voltage-developing means, and
voltage of one of said two relay-circuits with the
line-conditions more sensitively than said cur
means controlled by said ground-fault detector
means for making said current-responsive volt
age-developing means respond more sensitively to
said function of the three-phase line-current.
WILLIAM K. SONNEMANN.
Документ
Категория
Без категории
Просмотров
0
Размер файла
916 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа