Embodiment
In order to make object of the present invention, technical scheme and advantage clearer, below in conjunction with drawings and Examples, the present invention is further elaborated.Should be appreciated that specific embodiment described herein, only in order to explain the present invention, is not intended to limit the present invention.
Shown in Figure 1, a kind of distance backup protection check method of supertension line, comprises the following steps:
Step S101, carries out checking apart from backup protection I section, is specially the operational mode of obtaining current electrical network, and carries out selectivity check according to the backup protection I section of adjusting the distance of the system data under this operational mode.As follows apart from backup protection I section check method:
According to the minimum experience impedance Z of protection place line end short circuit
gsminwith safety factor K
kcalculate apart from backup protection I section calculated value Z
jsI, and according to this apart from backup protection I section calculated value Z
jsIcarry out selectivity and check judgement, if Z
jsIbe greater than (1-δ) * Z
setI, selectivity meets, otherwise selectivity is dissatisfied, carries out alarm prompt (δ gets 0.07).
Wherein, Z
setIfor ground distance I section setting value; When line length is less than 20km, safety factor K
k=0.7 (1-5L), wherein L is line length, the km of unit; When line length is more than or equal to 20km, generally, safety factor gets 0.7, and in particular cases (as many times mutual inductance circuits) safety factor gets 0.5; In the time that total track length is less than 5km, K
kget 0.
Step S102, carries out checking apart from backup protection II section.
Concrete, above-mentioned process of carrying out checking apart from backup protection II section can comprise as follows:
Step S1021, carries out sensitivity check, according to sensitivity K
lmwith the maximum experience impedance Z of this line end short circuit
gsmaxcalculate apart from backup protection II section calculated value Z
jsII, and according to this apart from backup protection II section calculated value Z
jsIIcarry out sensitivity and check judgement, if Z
jsIIbe less than (1+ δ) * Z
setII, sensitivity meets; Otherwise sensitivity does not meet, and carries out alarm prompt; In formula, Z
setIIfor apart from standby II section setting value, δ gets 0.1;
Step S1022, if adjacent lines has transformer, according to this circuit positive sequence impedance Z
1with adjacent transformers resistance value Z'
tcalculate apart from backup protection II section calculated value Z
jsII, and the distance backup protection II section calculated value Z calculating according to this
jsIIcarry out selectivity and check judgement, if Z
jsIIbe greater than (1-δ) * Z
setII, do not stretch out adjacent main transformer, selectivity meets; Otherwise stretch out adjacent main transformer, selectivity does not meet, and carries out alarm prompt; In formula, δ gets 0.07; If adjacent lines transless, goes to step S1023;
Step S1023, if protection adjacent elements is circuit, II section does not coordinate with neighbor distance backup protection I section, does not need coordinating and check with neighbor distance backup protection I section; If apart from backup protection II section time T
setIIbe less than min (T'
dzII+ Δ T, T
maxII), illustrate that II section coordinates with adjacent pilot protection, can be according to this circuit positive sequence impedance Z
1with adjacent lines positive sequence impedance value Z
1' calculate apart from backup protection II section calculated value Z
jsII, and the distance backup protection II section calculated value Z calculating according to this
jsIIcarry out selectivity and check judgement, if Z
jsIIbe greater than (1-δ) * Z
setII, selectivity meets; Otherwise selectivity does not meet, and carries out alarm prompt; In formula, T'
dzIIfor the adjacent lines protection II section time; Δ T is that the time is differential, generally gets 0.2S; T
maxIIfor apart from backup protection II section time definite value, be above limited to 2S; δ gets 0.07;
Step S1024, if min is (T'
dzII+ Δ T, T
maxII) be less than or equal to T
setII, illustrate that the distance backup protection II section of adjacent lines coordinates, can be according to this circuit positive sequence impedance Z
1with neighbor distance backup protection II section definite value Z'
dzIIcalculate apart from backup protection II calculated value Z
jsII, and the distance protection II section calculated value Z calculating according to this
jsIIcarry out selectivity and check judgement, if Z
jsIIbe greater than (1-δ) * Z
setII, selectivity meets; Otherwise do not meet selectivity, carry out alarm prompt, in formula, δ gets 0.07.
As a good embodiment, described according to this circuit positive sequence impedance Z
1with adjacent transformers resistance value Z'
tcalculate apart from backup protection II section calculated value Z
jsIIprocess specifically can comprise as follows:
Adopt following formula to calculate apart from backup protection II section calculated value Z
jsII: Z
jsII=K
k* Z
1+ K
kTk
zz'
t; In formula, K
kfor safety factor, get 0.8; K
kTfor cooperation coefficient, get 0.8; K
zfor helping increasing coefficient under current operational mode.
As a good embodiment, described according to this circuit positive sequence impedance Z
1with adjacent lines positive sequence impedance value Z
1' calculate apart from backup protection II section calculated value Z
jsIIprocess specifically can comprise as follows:
Adopt following formula to calculate apart from backup protection II section calculated value Z
jsII: Z
jsII=K
k* Z
1+ K
kk
zz
1'; In formula, K
kfor safety factor, get 0.7; K
zfor helping increasing coefficient under front operational mode.
As a good embodiment, described according to this circuit positive sequence impedance Z
1with neighbor distance backup protection II section definite value Z'
dzIIcalculate apart from backup protection II calculated value Z
jsIIprocess specifically can comprise as follows:
Adopt following formula to calculate apart from backup protection II section calculated value Z
jsII: Z
jsII=K
k* Z
1+ K
kk
zz'
dzII, in formula, K
kfor safety factor, get 0.8; K
zfor helping increasing coefficient under front operational mode.
It should be noted that the distance backup protection check method of a kind of supertension line of the present invention comprises ground distance backup protection check method and phase spacing backup protection check method.Because ground distance backup protection check method is consistent with phase spacing backup protection check method, therefore only describe the solution of the present invention in detail as an example of ground distance backup protection check example below:
As shown in Figure 2, line-to-ground apart from backup protection II section sensitivity check method is:
Z
jsII=K
lm*Z
gsmax;
Wherein: K
lmfor sensitivity; Z
gsmaxfor the maximum experience impedance of this line end short circuit.
Criterion: if Z
jsII< (1+ δ) * Z
setII, sensitivity meets, otherwise sensitivity does not meet (δ gets 0.1), carries out alarm prompt.In formula, Z
jsIIfor ground distance II section calculated value, Z
setIIfor ground distance II section setting value.
Apart from backup protection II section sensitivity K
lmrequire as follows:
A) when line length is less than 50km, K
lm=1.5;
B) when line length is between 50km and 100km, K
lm=1.45;
C) when line length is between 100km and 150km, K
lm=1.4;
D) when line length is between 150km and 200km, K
lm=1.35;
E) when line length is greater than 200km, K
lm=1.3.
(1) whether stretch out adjacent main transformer, selectivity is checked:
Z
jsII=K
k*Z
1+K
kTK
zZ'
T
Wherein: K
kfor safety factor, get 0.8; K
kTfor cooperation coefficient, get 0.8; Z
1for this circuit positive sequence impedance; Z'
tfor adjacent transformers resistance value; K
zfor helping increasing coefficient under current operational mode.
Criterion: if Z
jsII> (1-δ) * Z
setII, do not stretch out adjacent main transformer, selectivity meets, otherwise stretches out adjacent main transformer, and selectivity does not meet, and carries out alarm prompt.(δ gets 0.07).
(2) protection adjacent elements is circuit, and II section does not coordinate with neighbor distance backup protection I section, therefore do not need coordinating and check with neighbor distance backup protection I section.
I) min (T'
dzII+ Δ T, T
maxII) >T
setII, coordinate with adjacent pilot protection:
Z
jsII=K
k*Z
1+K
kK
zZ
1';
Wherein: K
kfor safety factor, get 0.7; K
zfor helping increasing coefficient under current operational mode; Z
1for this circuit positive sequence impedance; Z
1' be adjacent lines positive sequence impedance value; T'
dzIIfor the mating protection II section time; Δ T is that the time is differential, generally gets 0.2S, T
maxIIfor apart from backup protection II section time definite value, be above limited to 2S.
Criterion: if Z
jsII> (1-δ) * Z
setII, selectivity meets, otherwise selectivity is dissatisfied, carries out alarm prompt.Wherein, Z
setIIfor ground distance II section setting value, δ gets 0.07.
Ii) min (T'
dzII+ Δ T, T
maxII) £ T
setII, coordinate with the distance backup protection II section of adjacent lines:
Z
jsII=K
k*Z
1+K
kK
zZ'
dzII;
Wherein: K
kfor safety factor, get 0.8; K
zfor helping increasing coefficient under current operational mode; Z
1for this circuit positive sequence impedance; Z'
dzIIfor neighbor distance backup protection II section definite value; T'
dzIIfor the mating protection II section time; Δ T is that the time is differential, generally gets 0.2S, T
maxIIfor apart from backup protection II section time definite value, be above limited to 2S.
Criterion: if Z
jsII> (1-δ) * Z
setII, selectivity meets, otherwise does not meet selectivity, carries out alarm prompt.(δ gets 0.07)
As shown in Figure 1, as a good embodiment, the present invention, after the backup protection II section of adjusting the distance has been checked, can also comprise step S103: carry out checking apart from backup protection III section.This process specifically can comprise as follows:
Step S1031, according to the sensitivity K of twice
lmwith the maximum experience impedance Z of this line end short circuit
gsmaxcalculate distance and protect III section calculated value Z below
jsIII, and according to this apart from backup protection III section calculated value Z
jsIIIcarry out sensitivity and check judgement, if Z
jsIIIbe less than (1+ δ) * Z
setIII, sensitivity meets; Otherwise sensitivity does not meet, and carries out alarm prompt; In formula, Z
setIIIfor apart from III section setting value; δ gets 0.1;
Step S1032, if apart from backup protection III section time T
setIIIbe less than min (T'
dzII+ Δ T, T
maxIII), III segment protect coordinates with adjacent lines pilot protection, according to this circuit positive sequence impedance Z
1with adjacent lines positive sequence impedance definite value Z
1' calculate apart from backup protection III section calculated value Z
jsIII, and the distance backup protection III section calculated value Z calculating according to this
jsIIIcarry out selectivity and check judgement, if Z
jsIIIbe greater than (1-δ) * Z
setIII, selectivity meets; Otherwise do not meet selectivity, carry out alarm prompt; In formula, T'
dzIIfor adjacent lines is apart from backup protection II section operate time; Δ T is that the time is differential, generally gets 0.2S; T
maxIIIfor the maximum actuation time of protection III section, be 4.2S; δ gets 0.07;
Step S1033, if apart from backup protection III section time T
setIIIbe less than min (T'
dzIII+ Δ T, T
maxIII) and be more than or equal to min (T'
dzII+ Δ T, T
maxIII), III segment protect coordinates with the distance backup protection II section of adjacent lines, according to this circuit positive sequence impedance Z
1with adjacent lines apart from backup protection II section action definite value Z'
iIcalculate apart from backup protection III section calculated value Z
jsIII, and the distance backup protection III section calculated value Z calculating according to this
jsIIIcarry out selectivity and check judgement, if Z
jsIIIbe greater than (1-δ) * Z
setIII, selectivity meets; Otherwise do not meet selectivity, carry out alarm prompt, in formula, δ gets 0.07;
Step S1034, if ground distance backup protection III section time T
setIIIbe more than or equal to min (T'
dzIII+ Δ T, T
maxIII), III segment protect coordinates with adjacent lines distance protection III section, according to this circuit positive sequence impedance Z
1with adjacent lines apart from backup protection III section action definite value Z'
iIIcalculate apart from backup protection III calculated value Z
jsIII, and the distance backup protection III section calculated value Z calculating according to this
jsIIIcarry out selectivity and check judgement, if Z
jsIIIbe greater than (1-δ) * Z
setIII, selectivity meets; Otherwise do not meet selectivity, carry out alarm prompt; In formula, δ gets 0.07;
Step S1035, according to minimum accident overload impedance Z corresponding to the maximum accident overload electric current of this circuit
fhminwith safety factor K
kcalculate apart from backup protection III section calculated value Z
jsIII, and the distance backup protection III section calculated value Z calculating according to this
jsIIIthe load of hiding is checked judgement, if Z
jsIIIbe greater than (1-δ) * Z
setIII, selectivity meets; Otherwise do not meet selectivity, carry out alarm prompt; In formula, δ gets 0.07.
As a good embodiment, described according to this circuit positive sequence impedance Z
1with adjacent lines positive sequence impedance definite value Z
1' calculate apart from backup protection III section calculated value Z
jsIIIprocess comprise:
Adopt following formula to calculate apart from backup protection III section calculated value Z
jsIII: Z
jsIII=K
k* Z
1+ K
kk
zz
1'; In formula, K
kfor safety factor, get 0.84; K
zfor helping increasing coefficient under current operational mode.
As a good embodiment, described according to this circuit positive sequence impedance Z
1with adjacent lines apart from backup protection II section action definite value Z'
iIcalculate apart from backup protection III section calculated value Z
jsIIIprocess comprise:
Adopt following formula to calculate apart from backup protection III section calculated value Z
jsIII: Z
jsIII=K
k* Z
1+ K
kk
zz'
iI; In formula, K
kfor safety factor, get 0.8, K
zfor helping increasing coefficient under current operational mode.
As a good embodiment, described according to this circuit positive sequence impedance Z
1with adjacent lines apart from backup protection III section action definite value Z'
iIIcalculate apart from backup protection III calculated value Z
jsIII
Adopt following formula to calculate apart from backup protection III section calculated value Z
jsIII: Z
jsIII=K
k* Z
1+ K
kk
zz'
iII; In formula, K
kfor safety factor, get 0.8, K
zfor helping increasing coefficient under current operational mode.
Still be elaborated as an example of ground distance backup protection example below:
As shown in Figure 3, line-to-ground apart from backup protection III section sensitivity check method is:
Z
jsIII=2K
lm*Z
gsmax;
Wherein: K
lmfor sensitivity; Z
gsmaxfor the maximum experience impedance of this line end short circuit;
Criterion: if Z
jsIII< (1+ δ) * Z
setIII, sensitivity meets, otherwise sensitivity is dissatisfied, carries out alarm prompt.In formula, Z
jsIIIfor ground distance III section calculated value, Z
setIIIfor ground distance III section setting value, δ gets 0.1.
The sensitivity K of ground distance backup protection III section
lmrequire as follows:
A) when line length is less than 25km, K
lm=2.2;
B) when line length is between 25km and 50km, K
lm=2.0;
C) when line length is between 50km and 100km, K
lm=1.8;
D) when line length is between 100km and 150km, K
lm=1.6;
E) when line length is between 150km and 200km, K
lm=1.5;
F) when line length is greater than 200km, K
lm=1.4.
(1) min (T'
dzII+ Δ T, T
maxIII) >T
setIIIfirst coordinate with adjacent lines pilot protection:
Z
jsIII=K
k*Z
1+K
kK
zZ
1';
Wherein: K
kfor safety factor, get 0.84; K
zfor helping increasing coefficient under current operational mode; Z
1for this circuit positive sequence impedance; Z
1' be adjacent lines positive sequence impedance definite value; T'
dzIIfor adjacent lines ground distance backup protection II section operate time; Δ T is that the time is differential, generally gets 0.2S; T
maxIIIfor the maximum actuation time of ground protection III section, be 4.2S, T
setIIIfor ground distance backup protection III section setting time.
Criterion: if Z
jsIII> (1-δ) * Z
setIII, selectivity meets, otherwise does not meet selectivity, carries out alarm prompt (δ gets 0.07).
(2) min (T'
dzIII+ Δ T, T
maxIII) >T
setIII3min (T'
dzII+ Δ T, T
maxIII) coordinate with the distance backup protection II section of adjacent lines:
Z
jsIII=K
k*Z
1+K
kK
zZ'
II;
Wherein: K
kfor safety factor, get 0.8; K
zfor helping increasing coefficient under current operational mode; Z
1for this circuit positive sequence impedance; Z'
iIfor adjacent lines is apart from backup protection II section action definite value; T'
dzIIfor adjacent lines ground distance backup protection II section operate time; T'
dzIIIfor adjacent lines ground distance backup protection III section operate time; Δ T is that the time is differential, generally gets 0.2S; T
maxIIIfor the maximum actuation time of ground protection III section, be 4.2S.
Criterion: if Z
jsIII> (1-δ) * Z
setIII, selectivity meets, otherwise does not meet selectivity, carries out alarm prompt (δ gets 0.07).
(3) T
setII>=min (T'
dzIII+ Δ T, T
maxIII) coordinate with adjacent lines distance protection III section:
Z
jsIII=K
k*Z
1+K
kK
zZ'
III;
Wherein: K
kfor safety factor, get 0.8; K
zfor helping increasing coefficient under current operational mode; Z
1for this circuit positive sequence impedance; Z'
iIIfor adjacent lines is apart from backup protection III section action definite value; T'
dzIIIfor adjacent lines is apart from backup protection III section operate time; Δ T is that the time is differential, generally gets 0.2S; T
maxIIIfor the maximum actuation time apart from backup protection III section, be 4.2S.
Criterion: if Z
jsIII> (1-δ) * Z
setIII, selectivity meets, otherwise does not meet selectivity, carries out alarm prompt (δ gets 0.07).
(4) escape the minimum load impedance of this circuit:
Z
jsIII=K
k*Z
fhmin;
Wherein: K
kfor safety factor, get 0.7; Z
fhminfor minimum accident overload impedance corresponding to the maximum accident overload electric current of this circuit;
Criterion: if Z
jsIII> (1-δ) * Z
setIII, selectivity meets, otherwise does not meet selectivity, carries out alarm prompt (δ gets 0.07).
Can find out by above scheme, a kind of supertension line of the present invention is apart from backup protection check method, first corresponding apart from backup protection calculated value when calculating under previous mode, and then carry out sensitivity check, selectivity is checked judgement, this method is than the check method based on protection range, do not reducing under the prerequisite of power grid security risk, the huge amount of calculation of protection range and the problem of inaccuracy are not only avoided asking for, make to check calculating convenient, quick and accurate, alleviate and checked the workload of calculating, and be consistent in style with protection system calculation principle in form, be convenient to the realization of computer, possesses good versatility with portable.
It should be noted that, although the step in the present invention is arranged with label, but and be not used in and limit the precedence of step, unless expressly stated the order of step or the execution of certain step need other steps as basis, otherwise the relative order of step is adjustable.
The above embodiment has only expressed several execution mode of the present invention, and it describes comparatively concrete and detailed, but can not therefore be interpreted as the restriction to the scope of the claims of the present invention.It should be pointed out that for the person of ordinary skill of the art, without departing from the inventive concept of the premise, can also make some distortion and improvement, these all belong to protection scope of the present invention.Therefore, the protection range of patent of the present invention should be as the criterion with claims.