EP0239268A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Fault point locating method, fault point resistance measuring method, and impedance to fault point measuring method, and apparatus therefor
Assignee: Mitsubishi Electric Corp
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Filing: 1987-03-05
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Granted: —
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Expires: 2007-03-05
Abstract
Abstract This invention relates to a method for locating a fault point in a two-terminal system transmission line, a method for measuring impedance to the fault point at a three-terminal system transmission line, and methods for measuring the fault point therefor, and locators and measuring apparatus for putting these methods in practical use. It is utilized that, when a fault point current is made reference, the sine component of voltage at the apparatus installation point is equal to the sine component of impedance drop to the fault point therefrom, and that a phase difference between the component of current flowing in the fault point from the apparatus installation side end and that of a fault point current of the sum of the components of current flowing from the apparatus installation end and of current flowing from the other end to the fault point are substituted into the equation representing the above relation, thereby enabling the fault location, fault point resistance measurement and impedance measurement to the fault point to be measured without using the voltage and current data of the other end.
Inventors
- 👤 Genzaburou C/O Seigyo Seisakusho Kotani
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 02:00
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/08; G01R31/081; G01R31/085; G01R27/00; G01R27/02; G01R27/16
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
249 words
A fault point locating method for a two-terminal system transmission line having both end power sources, characterized in that the distance ℓ from one end to the fault point is computed by the following equation: where a = |I| sin (a + λ), b = - {|I| (B cosλ + D sinλ)+|V| I sin(α+µ)}, c = |V| (B cosµ + D sinµ) |Z|: the absolute value of impedance Z per unit length of the transmission line and represented by , r: a resistance component per unit length of the transmission line, x: a reactance component per unit length of the transmission line, a: a line angle of the transmission line and a value represented by α = tan -1 ( ), r |I|: the absolute value of a current I at said one end side when a fault occurs, |V|: the absolute value of voltage V at said one end side when the fault occurs, λ: a value represented by α+(β-φT, µ: a value represented by θ+β-φT, β: a phase angle of I based on I 1 , 1 1 : an incremental current generated when the fault occurs and represented by I - I L , I L : a load current, ΦT: an angle of total impedance when the system is normal, θ: a phase angle of voltage V based on I, B: a reactance component from said one end to the other end, and D: a resistance component from said one end to the other end.
Claim 2
Dependent Claim
249 words
A fault point locating method for a two-terminal system transmission line having both end power sources, characterized in that the distance ℓ from one end to the fault point is computed by the following equation: where a = |I| sin (a + λ), b = - {|I| (B cosλ + D sinλ)+|V| I sin(α+µ)}, c = |V| (B cosµ + D sinµ) |Z|: the absolute value of impedance Z per unit length of the transmission line and represented by , r: a resistance component per unit length of the transmission line, x: a reactance component per unit length of the transmission line, a: a line angle of the transmission line and a value represented by α = tan -1 ( ), r |I|: the absolute value of a current I at said one end side when a fault occurs, |V|: the absolute value of voltage V at said one end side when the fault occurs, λ: a value represented by α+(β-φT, µ: a value represented by θ+β-φT, β: a phase angle of I based on I 1 , 1 1 : an incremental current generated when the fault occurs and represented by I - I L , I L : a load current, ΦT: an angle of total impedance when the system is normal, θ: a phase angle of voltage V based on I, B: a reactance component from said one end to the other end, and D: a resistance component from said one end to the other end.
Claim 3
Dependent Claim
296 words
A fault locator for locating a fault in a two-terminal system transmission line having both end power sources, comprising means for detecting a current and voltage at one end, means for obtaining a phase angle from detected current and voltage, and a computing unit for carrying out the following equation by use of the data obtained directly or indirectly by both said means and the preset data, thereby computing the distance ℓ from said one end to the fault point: where a = |I| sin (a + λ), b = - {| I I (B cosλ + D sinλ)+|V | sin(α+µ}, c = |V|(B cosµ + D sinµ) |Z|: the absolute value of impedance Z per unit length of the transmission line and represented by , r: a resistance component per unit length of the transmission line, x: a reactance component per unit length of the transmission line, a: a line angle of the transmission line and a value represented by a = tan -1 ( ), r | I|: the absolute value of a current I at said one end side when a fault occurs, |V|: the absolute value of voltage V at said one end side when the fault occurs, λ: a value represented by α(β-φT, µt: a value represented by θ+β-φT, β: a phase angle of I based on I 1 , I 1 : an incremental current generated when the fault occurs and represented by I - 1 L , I L : a load current, ΦT: an angle of total impedance when the system is normal, θ: a phase angle of voltage V based on I, B: a reactance component from said one end to the other end, and D: a resistance component from said one end to the other end.
Claim 4
Dependent Claim
296 words
A fault locator for locating a fault in a two-terminal system transmission line having both end power sources, comprising means for detecting a current and voltage at one end, means for obtaining a phase angle from detected current and voltage, and a computing unit for carrying out the following equation by use of the data obtained directly or indirectly by both said means and the preset data, thereby computing the distance ℓ from said one end to the fault point: where a = |I| sin (a + λ), b = - {| I I (B cosλ + D sinλ)+|V | sin(α+µ}, c = |V|(B cosµ + D sinµ) |Z|: the absolute value of impedance Z per unit length of the transmission line and represented by , r: a resistance component per unit length of the transmission line, x: a reactance component per unit length of the transmission line, a: a line angle of the transmission line and a value represented by a = tan -1 ( ), r | I|: the absolute value of a current I at said one end side when a fault occurs, |V|: the absolute value of voltage V at said one end side when the fault occurs, λ: a value represented by α(β-φT, µt: a value represented by θ+β-φT, β: a phase angle of I based on I 1 , I 1 : an incremental current generated when the fault occurs and represented by I - 1 L , I L : a load current, ΦT: an angle of total impedance when the system is normal, θ: a phase angle of voltage V based on I, B: a reactance component from said one end to the other end, and D: a resistance component from said one end to the other end.
Claim 5
Independent Claim
282 words
A method for measuring fault point resistance at a two-terminal system transmission line having both end power sources, characterized in that the fault point resistance R F is computed by the following equation: where a = I I sin (a + λ), b = - {|I|(B cosλ + D sinλ)+|V| sin(α+µ)), c = IV I (B cosµ + D sinµ) Z, |Z|: Z is impedance per unit length of the transmission line and |Z I is the absolute value of Z and represented by r: a resistance component per unit length of the transmission line, x: a reactance component per unit length of the transmission line, a: a line angle of the transmission line and a value x represented by a = tan -1 (x/r), r I, |I|: a current flowing in one end when a fault occurs and the absolute value thereof, V, |V|: a voltage at said one end when the fault occurs and the absolute value thereof, λ: a value represented by α+β-φT, µt: a value represented by θ+β-φT, β: a phase angle of I based on I 1 , I : an incremental current generated when the fault occurs and represented by I - I L , I L : a load current, Z T : total impedance when the system is normal, Z Q : the sum of impedance from the fault point to the other end and back impedance thereof, φT: an angle of total impedance when the system is normal, 6: a phase angle of voltage V based on I, B: a reactance component from said one end to the other end, and D: a resistance component from said one end to the other end.
Claim 6
Independent Claim
282 words
A method for measuring fault point resistance at a two-terminal system transmission line having both end power sources, characterized in that the fault point resistance R F is computed by the following equation: where a = I I sin (a + λ), b = - {|I|(B cosλ + D sinλ)+|V| sin(α+µ)), c = IV I (B cosµ + D sinµ) Z, |Z|: Z is impedance per unit length of the transmission line and |Z I is the absolute value of Z and represented by r: a resistance component per unit length of the transmission line, x: a reactance component per unit length of the transmission line, a: a line angle of the transmission line and a value x represented by a = tan -1 (x/r), r I, |I|: a current flowing in one end when a fault occurs and the absolute value thereof, V, |V|: a voltage at said one end when the fault occurs and the absolute value thereof, λ: a value represented by α+β-φT, µt: a value represented by θ+β-φT, β: a phase angle of I based on I 1 , I : an incremental current generated when the fault occurs and represented by I - I L , I L : a load current, Z T : total impedance when the system is normal, Z Q : the sum of impedance from the fault point to the other end and back impedance thereof, φT: an angle of total impedance when the system is normal, 6: a phase angle of voltage V based on I, B: a reactance component from said one end to the other end, and D: a resistance component from said one end to the other end.
Claim 7
Independent Claim
319 words
An apparatus for measuring fault point resistance Rp at a two-terminal system transmission line having both end power sources, comprising, means for detecting a current and voltage at one end, means for obtaining a phase angle from detected current and voltage, and a computing unit for computing the following equation by use of the data obtained directly or indirectly by both said means and the preset data: where a = I I sin (a + λ), b = - {|I| (B cosλ + D sinλ)+|V| sin(α+µ)}, c = I V I (B cosµ + D sinµ) Z, |Z|: Z is impedance per unit length of the transmission line and |Z| is the absolute value of Z and represented by , r: a resistance component per unit length of the transmission line, x: a reactance component per unit length of the transmission line, a: a line angle of the transmission line and a value x represented by a = tan -1 (x/r), r I, |I|: a current flowing in one end when a fault occurs and the absolute value thereof, V, |V|: a voltage at said one end when the fault occurs and the absolute value thereof, λ: a value represented by α+β-φT, µ: a value represented by θ+β-φT, β: a phase angle of I based on I 1 , I 1 : an incremental current generated when the fault occurs and represented by I - I L , I L : a load current, Z T : total impedance when the system is normal, Z Q : the sum of impedance from the fault point to the other end and back impedance thereof, φT: an angle of total impedance when the system is normal, θ: a phase angle of voltage V based on I, B: a reactance component from said one end to the other end, and D: a resistance component from said one end to the other end.
Claim 8
Independent Claim
319 words
An apparatus for measuring fault point resistance Rp at a two-terminal system transmission line having both end power sources, comprising, means for detecting a current and voltage at one end, means for obtaining a phase angle from detected current and voltage, and a computing unit for computing the following equation by use of the data obtained directly or indirectly by both said means and the preset data: where a = I I sin (a + λ), b = - {|I| (B cosλ + D sinλ)+|V| sin(α+µ)}, c = I V I (B cosµ + D sinµ) Z, |Z|: Z is impedance per unit length of the transmission line and |Z| is the absolute value of Z and represented by , r: a resistance component per unit length of the transmission line, x: a reactance component per unit length of the transmission line, a: a line angle of the transmission line and a value x represented by a = tan -1 (x/r), r I, |I|: a current flowing in one end when a fault occurs and the absolute value thereof, V, |V|: a voltage at said one end when the fault occurs and the absolute value thereof, λ: a value represented by α+β-φT, µ: a value represented by θ+β-φT, β: a phase angle of I based on I 1 , I 1 : an incremental current generated when the fault occurs and represented by I - I L , I L : a load current, Z T : total impedance when the system is normal, Z Q : the sum of impedance from the fault point to the other end and back impedance thereof, φT: an angle of total impedance when the system is normal, θ: a phase angle of voltage V based on I, B: a reactance component from said one end to the other end, and D: a resistance component from said one end to the other end.
Claim 9
Independent Claim
296 words
A method for measuring impedance from one end to a fault point at a three-terminal system transmission line, characterized in that the distance ℓ from one end to the fault point is computed by the following equation: where a = |I P | sin (a + λ), b = - {|I P | (B cosλ + D sinλ)+|V P | sin(α+µ)}, c = |V P | (Bcosµ + Dsinµ) |Z|: the absolute value of impedance Z per unit length of the transmission line and represented by . r: a resistance component per unit length of the transmission line, x: a reactance component per unit length of the transmission line, a: a line angle of the transmission line and a value represented by a = tan -1 (x/r), r |I P |: the absolute value of a current Ip, flowing in said one end when a fault occurs, |V P |: the absolute value of voltage V P at said one end side when the fault occurs, λ: a value represented by α+β-φT, µ: a value represented by θ+β-φT, β: a phase angle of Ip based on I 1 , I : an incremental current generated when a fault occurs and represented by Ip - IL 1 , I L1 : a load current, φT: an impedance angle of ZS + Zp , Z S : impedance when the other end is viewed from the junction at the system, Z P : the sum of impedance from said one end to the junction at the system and back impedance, 8: a phase angle of voltage V P based on I P , B: a reactance component from said one end to the other end, and D: a resistance component from said one end to the other end.
Claim 10
Independent Claim
296 words
A method for measuring impedance from one end to a fault point at a three-terminal system transmission line, characterized in that the distance ℓ from one end to the fault point is computed by the following equation: where a = |I P | sin (a + λ), b = - {|I P | (B cosλ + D sinλ)+|V P | sin(α+µ)}, c = |V P | (Bcosµ + Dsinµ) |Z|: the absolute value of impedance Z per unit length of the transmission line and represented by . r: a resistance component per unit length of the transmission line, x: a reactance component per unit length of the transmission line, a: a line angle of the transmission line and a value represented by a = tan -1 (x/r), r |I P |: the absolute value of a current Ip, flowing in said one end when a fault occurs, |V P |: the absolute value of voltage V P at said one end side when the fault occurs, λ: a value represented by α+β-φT, µ: a value represented by θ+β-φT, β: a phase angle of Ip based on I 1 , I : an incremental current generated when a fault occurs and represented by Ip - IL 1 , I L1 : a load current, φT: an impedance angle of ZS + Zp , Z S : impedance when the other end is viewed from the junction at the system, Z P : the sum of impedance from said one end to the junction at the system and back impedance, 8: a phase angle of voltage V P based on I P , B: a reactance component from said one end to the other end, and D: a resistance component from said one end to the other end.
Claim 11
Independent Claim
327 words
An apparatus for measuring impedance from one end to a fault point at a three-terminal system transmission line, comprising means for detecting a current and voltage at one end, means for obtaining a phase angle from detected current and voltage, and a computation unit for computing the following equation by use of the data obtained directly or indirectly by both means and the preset data: where a = |I P | sin (a + λ), b = - {|I P | (B cos λ + D sinrl)+|V P | sin(α+µ)), c = |V P | (B coslµ + D sinµ) |Z|: the absolute value of impedance Z per unit length of the transmission line and represented by , r: a resistance component per unit length of the transmission line, x: a reactance component per unit length of the transmission line, a: a line angle of the transmission line and a value x represented by a = tan -1 (x/r), r |I P |: the absolute value of a current Ip flowing in said one end when a fault occurs, |V P |: the absolute value of voltage Vp at said one end side when the fault occurs, λ: a value represented by α+β-φT, µt: a value represented by θ+β-φT, β: a phase angle of I p based on I 1 , I 1 : an incremental current generated when the fault occurs and represented by Ip - I L1 , I L1 : a load current, φT: an impedance angle of Zs + Zp , Z S : impedance when the other end is viewed from the junction at the system, Zp: the sum of impedance from said one end to the junction at the system and back impedance, θ: a phase angle of voltage V P based on I P , B: a reactance component from said one end to the other end, and D: a resistance component from said one end to the other end.
Claim 12
Independent Claim
327 words
An apparatus for measuring impedance from one end to a fault point at a three-terminal system transmission line, comprising means for detecting a current and voltage at one end, means for obtaining a phase angle from detected current and voltage, and a computation unit for computing the following equation by use of the data obtained directly or indirectly by both means and the preset data: where a = |I P | sin (a + λ), b = - {|I P | (B cos λ + D sinrl)+|V P | sin(α+µ)), c = |V P | (B coslµ + D sinµ) |Z|: the absolute value of impedance Z per unit length of the transmission line and represented by , r: a resistance component per unit length of the transmission line, x: a reactance component per unit length of the transmission line, a: a line angle of the transmission line and a value x represented by a = tan -1 (x/r), r |I P |: the absolute value of a current Ip flowing in said one end when a fault occurs, |V P |: the absolute value of voltage Vp at said one end side when the fault occurs, λ: a value represented by α+β-φT, µt: a value represented by θ+β-φT, β: a phase angle of I p based on I 1 , I 1 : an incremental current generated when the fault occurs and represented by Ip - I L1 , I L1 : a load current, φT: an impedance angle of Zs + Zp , Z S : impedance when the other end is viewed from the junction at the system, Zp: the sum of impedance from said one end to the junction at the system and back impedance, θ: a phase angle of voltage V P based on I P , B: a reactance component from said one end to the other end, and D: a resistance component from said one end to the other end.
Claim 13
Independent Claim
306 words
A method for measuring fault point resistance at a three-terminal system transmission line, characterized in that fault point resistance R is computed by a following equation: where where a = |I P | sin (a + λ), b = - {|Ip | (B cos λ + D sinλ)+ I Vp I sin(α+µ)), c = |V P | (B cos µ + D sinµ) Z,|Z|: Z is impedance per unit length of the transmission line, and |Z| is the absolute value of Z per unit length of the transmission line and represented by , r: a resistance component per unit length of the transmission line, x: a reactance component per unit length of the transmission line, a: a line angle of the transmission line and a value x represented by a = tari -1 (-), r Ip, |I P |: a current flowing in said one end when a fault occurs and the absolute value thereof, V P , |V P | voltage at said one end when the fault t occurs and the absolute value thereof, λ: a value represented by α+β-φT, µ: a value represented by θ+β-φT, β: a phase angle of I P based on I 1 , I 1 : an incremental current generated when the fault occurs and represented by Ip - I L1 , I L1 : a load current, φT: an impedance angle of Zs + Z P , Z S : impedance when the other end is viewed from the junction at the system, Z P : the sum of impedance from said one end to the junction at the system and back impedance, θ: a phase angle of voltage Vp based on Ip, B: a reactance component from said one end to the other end, and D: a resistance component from said one end to the other end.
Claim 14
Independent Claim
306 words
A method for measuring fault point resistance at a three-terminal system transmission line, characterized in that fault point resistance R is computed by a following equation: where where a = |I P | sin (a + λ), b = - {|Ip | (B cos λ + D sinλ)+ I Vp I sin(α+µ)), c = |V P | (B cos µ + D sinµ) Z,|Z|: Z is impedance per unit length of the transmission line, and |Z| is the absolute value of Z per unit length of the transmission line and represented by , r: a resistance component per unit length of the transmission line, x: a reactance component per unit length of the transmission line, a: a line angle of the transmission line and a value x represented by a = tari -1 (-), r Ip, |I P |: a current flowing in said one end when a fault occurs and the absolute value thereof, V P , |V P | voltage at said one end when the fault t occurs and the absolute value thereof, λ: a value represented by α+β-φT, µ: a value represented by θ+β-φT, β: a phase angle of I P based on I 1 , I 1 : an incremental current generated when the fault occurs and represented by Ip - I L1 , I L1 : a load current, φT: an impedance angle of Zs + Z P , Z S : impedance when the other end is viewed from the junction at the system, Z P : the sum of impedance from said one end to the junction at the system and back impedance, θ: a phase angle of voltage Vp based on Ip, B: a reactance component from said one end to the other end, and D: a resistance component from said one end to the other end.
Claim 15
Independent Claim
341 words
An apparatus for measuring a fault point resistance R at a three-terminal system transmission line, comprising means for detecting a current and voltage at one end, means for obtaining a phase angle from detected current and voltage, and a computing unit for computing the following equation by use of the data obtained directly or indirectly by said both means and the preset data: where where a = |Ip| sin (a + λ), b = - {|I P |(B cosλ + D sinλ)+(V P I sin(α+µ)}, c = I Vpl (B cosµ + D sinµ) Z,|Z|: Z is impedance per unit t length of the transmission line, and |Z| is the absolute value of Z per unit length of the transmission line and represented by , r: a resistance component per unit length of the transmission line, x: a reactance component per unit length of the transmission line, a: a line angle of the transmission line and a value x represented by a = tan -1 (x/r), r I P , |I P |: a current flowing in said one end when a fault occurs and the absolute value thereof, V P , |V P | : voltage at said one end when the fault occurs and the absolute value thereof, A: a value represented by α+β-φT, µ: a value represented by θ+β-φT, β: a phase angle of Ip based on I 1 , 1 1 : an incremental current generated when the fault occurs and represented by I P - I L1 , I L1 : a load current, φT: an impedance angle of Z S + Z P , Z S : impedance when the other end is viewed from the junction at the system, Zp: the sum of impedance from said one end to the junction at the system and back impedance, θ: a phase angle of voltage Vp based on I P , B: a reactance component from said one end to the other end, and D: a resistance component from said one end to the other end.
Claim 16
Independent Claim
341 words
An apparatus for measuring a fault point resistance R at a three-terminal system transmission line, comprising means for detecting a current and voltage at one end, means for obtaining a phase angle from detected current and voltage, and a computing unit for computing the following equation by use of the data obtained directly or indirectly by said both means and the preset data: where where a = |Ip| sin (a + λ), b = - {|I P |(B cosλ + D sinλ)+(V P I sin(α+µ)}, c = I Vpl (B cosµ + D sinµ) Z,|Z|: Z is impedance per unit t length of the transmission line, and |Z| is the absolute value of Z per unit length of the transmission line and represented by , r: a resistance component per unit length of the transmission line, x: a reactance component per unit length of the transmission line, a: a line angle of the transmission line and a value x represented by a = tan -1 (x/r), r I P , |I P |: a current flowing in said one end when a fault occurs and the absolute value thereof, V P , |V P | : voltage at said one end when the fault occurs and the absolute value thereof, A: a value represented by α+β-φT, µ: a value represented by θ+β-φT, β: a phase angle of Ip based on I 1 , 1 1 : an incremental current generated when the fault occurs and represented by I P - I L1 , I L1 : a load current, φT: an impedance angle of Z S + Z P , Z S : impedance when the other end is viewed from the junction at the system, Zp: the sum of impedance from said one end to the junction at the system and back impedance, θ: a phase angle of voltage Vp based on I P , B: a reactance component from said one end to the other end, and D: a resistance component from said one end to the other end.
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