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Class Information
Number: 361/80
Name: Electricity: electrical systems and devices > Safety and protection of systems and devices > With specific quantity comparison means > Voltage and current > Distance relaying
Description: Subject matter wherein the voltages and currents are sensed at specific points in a system and computed with each other or with reference quantities to determine if a fault condition exists in the protected line section.

Sub-classes under this class:

Class Number Class Name Patents
361/81 With communication means between disconnect points 59

Patents under this class:
1 2 3 4

Patent Number Title Of Patent Date Issued
8675327 Fast impedance protection technique immune to dynamic errors of capacitive voltage transformers Mar. 18, 2014
8649131 Method and device for supervising secondary circuit of instrument transformer in power system Feb. 11, 2014
8575942 Non-contacting method and apparatus for determining contact voltage sources and providing a warning for same Nov. 5, 2013
8456119 Driving device of brushless DC motor for fan and driving method thereof Jun. 4, 2013
8451570 Method for production of an oscillating signal and of an electrical protection device or measurement instrument having an oscillation identification device May. 28, 2013
8396098 Digital protective relay device and data transmission device for the same Mar. 12, 2013
8295494 Enhancing audio with remixing capability Oct. 23, 2012
8285500 System and method for providing power distribution system information Oct. 9, 2012
8164285 External disturbance detection system and method for two-phase motor control systems Apr. 24, 2012
8159229 Load compensation in distance protection of a three-phase power transmission line Apr. 17, 2012
8145443 Fourier transform-based phasor estimation method and apparatus capable of eliminating influence of exponentially decaying DC offsets Mar. 27, 2012
8045307 Faulted phase decision method between current and voltage based delta phase selectors Oct. 25, 2011
8022709 Method and apparatus for determining circular characteristic Sep. 20, 2011
7973536 Traveling wave based relay protection Jul. 5, 2011
7872478 Method and adaptive distance protection relay for power transmission lines Jan. 18, 2011
7755872 System, method and device to preserve protection communication active during a bypass operation Jul. 13, 2010
7710693 Apparatus and method for providing protection for a synchronous electrical generator in a power system May. 4, 2010
7599161 Relay device and corresponding method Oct. 6, 2009
7542256 Relay device and corresponding method Jun. 2, 2009
7535233 Traveling wave based relay protection May. 19, 2009
7472026 Multi-ended fault location system Dec. 30, 2008
7457088 Systems and methods for protection of electrical networks Nov. 25, 2008
7345862 Protective relay for power systems having fault distance measurement filter logic Mar. 18, 2008
7345863 Apparatus and method for identifying a loss of a current transformer signal in a power system Mar. 18, 2008
7299143 Method and apparatus for improving operational reliability during a loss of a phase voltage Nov. 20, 2007
7233470 Distance relay apparatus Jun. 19, 2007
7199989 Digital protection relay with time sync function Apr. 3, 2007
7085938 Protective relay with embedded web server Aug. 1, 2006
7050913 Method and apparatus for monitoring power quality in an electric power distribution system May. 23, 2006
6989977 Digital directional relay Jan. 24, 2006
6944554 Method for detecting fault on transmission lines by using harmonics and state transition diagram Sep. 13, 2005
6924647 Fault location method and device Aug. 2, 2005
6879917 Double-ended distance-to-fault location system using time-synchronized positive-or negative-sequence quantities Apr. 12, 2005
6873508 Protective relay system Mar. 29, 2005
6833711 Protective relay for powers systems having dependable out-of-step blocking capability Dec. 21, 2004
6829544 Line current differential protective relaying method and relay for in-zone tapped transformers Dec. 7, 2004
6760670 Crossover fault classification for power lines with parallel circuits Jul. 6, 2004
6741943 Crossover fault classification for power lines with parallel circuits May. 25, 2004
6738719 Crossover fault classification for power lines with parallel circuits May. 18, 2004
6661630 Distance relay for protection of transmission line having minimized reactance effect Dec. 9, 2003
6633166 Method for generating an error signal identifying a short circuit Oct. 14, 2003
6518767 Line differential protection system for a power transmission line Feb. 11, 2003
6498709 Digital distance relay Dec. 24, 2002
6483435 Method and device of fault location for distribution networks Nov. 19, 2002
6469629 Distributed logic in multiple protective relays Oct. 22, 2002
6459960 Distance relay equipment Oct. 1, 2002
6426856 Method for monitoring a protective gear Jul. 30, 2002
6397155 Method and apparatus for automatically controlled gain switching of monitors May. 28, 2002
6392857 Device and process for protecting a line of a network of electricity supply lines May. 21, 2002
6385022 Method and apparatus for deriving power system data from configurable source points May. 7, 2002

1 2 3 4

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