Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
  • G01R31/08—Locating faults in cables, transmission lines, or networks
  • G01R31/081—Locating faults in cables, transmission lines, or networks according to type of conductors
  • G01R31/086—Locating faults in cables, transmission lines, or networks according to type of conductors in power transmission or distribution networks, i.e. with interconnected conductors
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
  • Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
  • Y04S10/00—Systems supporting electrical power generation, transmission or distribution
  • Y04S10/50—Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications
  • Y04S10/52—Outage or fault management, e.g. fault detection or location

Definitions

• the invention is intended for the area of electrical power network and may be applied to a method of the earth fault place location and identification in a three-phase electrical distribution network.
• the main faults of electrical distribution networks are wire breaks and/or earth faults.
• Fault detection methods in electrical distribution networks are described in patents SU 1762279 and SU 1698849.
• Fault place location in patent SU 1762279 is based on useful reflection from the place of fault of signal identification and its usage for the fault location.
• a method of phase earth fault location is described in patent SU 1698848, where the first half-wave of the discharge current is fixed in a place of short circuit, two- component amplitudes of the discharge current of a half- wave spectrum are measured and under a respective formula distance to the earth fault place is founded.
• the invention presents a new method of earth fault location in a three-phase electrical network. It differs from the well-known methods by registration not only permanent but also short-term self-disappearing earth faults and more precise location of former or present earth faults between the phase and the earthed object in one section of a three-phase feeder substation connected to the bus section of the feeder substation. It permits the supervisory services of the electrical network to efficiently eliminate the occurred earth fault and/or to prevent possible faults, where for some reasons (the spark, touch of the tree branches, etc.) short-term earth faults occur.
• a method is characterised by its registration of the initial processes of zero-phase sequence and voltage variations after earth fault, which are registered at the voltage transformer connected to the bus section and in the feeder current transformer of a zero- phase sequence current.
• the better accuracy of the earth fault place location is achieved by not longer than 100 ⁇ s performance and smaller than 100 iis time intervals, decreasing by this noise influence, which frequency is lower than 10 IdHz, by special algebra separating the processes running in other feeders and loading them into a model, where the simulated process is compared with the registered one.
• the place of earth fault and model element parameters are found by minimising goal function which is the function of the difference between the registered and simulated processes.
• Fig. 1 presents a block-diagramme of the operational device for this method realisation
• Fig. 2 presents a scaling filter scheme of a high frequency current process.
• this invention uses a device schematically described in table 1, consisting of a zero-phase sequence current process identification and separation of analogue link block 1, identification of a zero-phase sequence voltage process and separation of analogue link block 2, transducers of analogue code and memory block 3, converting measured within earth fault analogue zero sequence current and voltage processes into a buffer memory, controllers block 4, co-ordinating identification of the registered process performing its analysis, modelling, parameters optimisation, fault identification and being in connection with the outer systems, interface and indication block 5 demonstrating the estimated distance to the place of earth fault
• earth fault between a phase and the earthed object in one three-phase feeder connected to the feeder substation bus section is located by registering in an analogue method after earth fault zero-phase sequence initial current I 0 and voltage U 0 variations processes in due blocks 1 and 2 obtained from a voltage transformer connected to a bus section and from the feeder's zero-phase sequence high frequency current scaling filter 6 (Fig. 2) equipped in block 1.
• Parameters of a high frequency current process scaling filter 6 depend on the feeder's section and configuration. Use of scaling filter 6 permits registering initial processes after earth fault of a zero-phase sequence high frequency current and locating faults more precisely.
• the method of this invention is composed of an algorithm, the processor of which is available in controller block 4, locates earth fault in the feeders' sections in the following stages.
• 1 [l, l,..., l] n2 ; rem and derem — algebra operations for equal clearance vectors characterised by following formulas:
• s k _ [ ⁇ S MM((kIc--lI))+ + jJ ) / AM . a. 1 Af(A-I)+! ' M(k- ⁇ ) + 2 'M(U-V) + M (VII) a h

Landscapes

• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Locating Faults (AREA)
• Emergency Protection Circuit Devices (AREA)
• Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
• Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)

Applications Claiming Priority (2)

Publications (1)

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Country Status (4)

Cited By (3)

Families Citing this family (7)

Family Cites Families (4)

• 2005
  • 2005-07-20 LT LT2005067A patent/LT5337B/lt not_active IP Right Cessation
• 2006
  • 2006-07-18 WO PCT/LT2006/000006 patent/WO2007011196A1/en not_active Ceased
  • 2006-07-18 RU RU2008105543/28A patent/RU2008105543A/ru not_active Application Discontinuation
  • 2006-07-18 EP EP06769357A patent/EP1904862A1/de not_active Withdrawn

Non-Patent Citations (1)

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