Systems and methods for identifying grid fault type and faulted phase

Patent metadata

Field	Value
Publication number	US-12287362-B2
Application number	US-202218053183-A
Country	US
Kind code	B2
Filing date	Nov 7, 2022
Priority date	Nov 7, 2022
Publication date	Apr 29, 2025
Grant date	Apr 29, 2025

Abstract

A system for detecting a fault type and faulted phase in a power grid includes a controller and a relay. The relay is configured to monitor a line of the power grid and generate a monitoring signal. The controller may be configured to determine, in response to the monitoring signal received from the relay, sequence voltages and sequence currents in the line. The controller may further determine, in response to the sequence voltages and sequence currents, an absence or a presence of a weak-infeed condition in the line. The controller may further determine, in response to the monitoring signal and the absence or the presence of the weak-infeed condition, a first plane sequence signature and a second plane sequence signature. The controller may further determine a fault type and faulted phase in the power grid in response to the first plane sequence signature and the second plane sequence signature.

First claim

We claim:

1. A system for detecting a fault type and faulted phase using two planes in a power grid, the system comprising:
a relay configured to monitor a line of the power grid by measuring three-phase voltages and three-phase currents and generate a monitoring signal; and
a controller, wherein the controller is configured to:
determine three-phase voltage phasors and three-phase current phasors, in response to three-phase voltages and three-phase current samples acquired from current and voltage instrument transformers;
determine a positive sequence voltage, a negative sequence voltage, a zero sequence voltage, and voltage magnitudes in response to phasors of the three-phase voltages;
determine a positive sequence current, a negative sequence current, a zero sequence current, and current magnitudes in response to phasors of the three-phase currents;
capture positive, negative, and zero sequence voltage phasors, positive, negative, and zero current phasors, positive, negative, and zero sequence voltage magnitudes, and positive, negative, and zero sequence current magnitudes;
determine, in response to the negative sequence current magnitude, an absence or a presence of a weak-infeed condition in the line;
determine, in response to the positive, negative, and zero sequence current magnitudes and to the positive, negative, and zero sequence voltage magnitudes, an enabling signal;
determine a delta change in the positive, negative, and zero sequence voltage phasors and a delta change in the positive, negative, and zero sequence current phasors, in response to the positive, negative, and zero sequence voltage phasors, in response to the positive, negative, and zero sequence current phasors, in response to the positive, negative, and zero sequence voltage phasors, and in response to the positive, negative, and zero sequence current phasors;
determine, in response to a first angle between a pair of delta change sequence quantities in a first of the two planes, a first plane sequence signature;
determine, in response to a second angle between two delta change sequence quantities in a second of the two planes, a second plane sequence signature;
determine an initial fault type and faulted phase in the power grid in response to the enabling signal, the first plane sequence signature, and the second plane sequence signature; and
determine a final fault type and faulted phase in the power grid, in response to the initial fault type and faulted phase, and the voltage magnitudes.

2. The system of claim 1 , wherein the first angle is between delta positive and delta negative voltage or current sequences, and wherein the second angle is between delta zero and delta negative voltage or current sequences.

3. The system of claim 1 , wherein the controller is further configured to, in response to the absence of the weak-infeed condition:
determine the first plane sequence signature comprising a first plane current sequence signature based on the first angle, wherein the first angle is between a delta positive current sequence and a delta negative-sequence current (ΔI 1 and ΔI 2 );
determine the second plane sequence signature comprising a second plane current signature based on the second angle, wherein the second angle is between a delta zero current sequence and the delta negative-sequence current (ΔI 0 and ΔI 2 );
determine a fault type and faulted phase in the first plane based on the first plane sequence signature and first plane sectors, wherein each plane sector in the first plane is defined by a first angle range;
determine a fault type and faulted phase in the second plane based on the second plane sequence signature and second plane sectors, wherein each plane sector in the second plane is defined by a second angle range; and
determine the final fault type and faulted phase based on the fault type and faulted phase in the first plane, the fault type and faulted phase in the second plane, and the enabling signal.

4. The system of claim 3 , wherein the controller is further configured to, in response to a failure to determine the final fault type and faulted phase based on a first plane current signature (ΔI 1 and ΔI 2 ) and a second plane current signature (ΔI 0 and ΔI 2 ):
determine the first plane sequence signature comprising a first plane voltage sequence signature based on the first angle, wherein the first angle is between a delta positive sequence voltage and a delta negative-sequence voltage (ΔV 1 and ΔV 2 );
determine the second plane sequence signature comprising a second plane voltage signature based on the second angle, wherein the second angle is between the delta negative sequence voltage and a delta zero-sequence voltage (ΔV 0 and ΔV 2 );
determine a fault type and faulted phase in the first plane based on the first plane sequence signature and first plane sectors, wherein each of the first plane sectors is defined by a first angle range that is pre-defined, settable, or adaptive;
determine a fault type and faulted phase in the second plane based on the second plane sequence signature and second plane sectors, wherein each of the second plane sectors is defined by a second angle range that is pre-defined, settable, or adaptive; and
determine the final fault type and faulted phase based on the fault type and faulted phase in the first plane, the fault type and faulted phase in the second plane, and the enabling signal.

5. The system of claim 1 , wherein the controller is configured to, in response to the presence of the weak-infeed condition or a presence of a non-synchronous generation:
determine the first plane sequence signature comprising a first plane voltage signature based on the first angle, wherein the first angle is between a delta positive-sequence voltage and a delta negative-sequence voltage (ΔV 1 and ΔV 2 );
determine the second plane sequence signature comprising a second plane voltage signature based on the second angle, wherein the second angle is between a delta zero-sequence voltage and the delta negative-sequence voltage (ΔV 0 and ΔV 2 );
determine a fault type and faulted phase in the first plane based on the first plane sequence signature and first plane sectors, wherein each of the first plane sectors is defined by a first angle range that is pre-defined, settable, or adaptive;
determine a fault type and faulted phase in the second plane based on the second plane sequence signature and second plane sectors, wherein each of the second plane sectors is defined by a second angle range that is pre-defined, settable, or adaptive; and
determine the initial fault type and faulted phase based on the fault type and faulted phase in the first plane, the fault type and faulted phase in the second plane, and the enabling signal.

6. The system of claim 5 , wherein the controller is further configured to, in response to failure to determine the initial fault type and faulted phase based on a first plane voltage signature (ΔV 1 and ΔV 2 ) and a second plane voltage signature (ΔV 0 and ΔV 2 ):
determine the first plane sequence signature comprising a first plane voltage sequence signature based on the first angle, wherein the first angle is between a delta positive sequence voltage and a delta negative-sequence voltage (ΔV 1 and ΔV 2 );
determine the second plane sequence signature comprising a second plane current signature based on the second angle, wherein the first angle is between a delta positive sequence current and a delta negative-sequence current (ΔI 0 and ΔI 2 );
determine the fault type and faulted phase in the first plane based on the first plane sequence signature and first plane sectors, wherein each of the first plane sectors is defined by a first angle range that is pre-defined, settable, or adaptive;
determine the fault type

Assignees

• General Electric Technology Gmbh
• Ge Infrastructure Technology Llc

Inventors

• Chakrapani Venkatesh
• Voloh Ilia

Classifications

• G06Q50/06

  Energy or water supply · CPC title

• H02H3/382

  involving phase comparison between current and voltage or between values derived from current and voltage · CPC title

• G01R31/086 Primary

  in power transmission or distribution networks, i.e. with interconnected conductors · CPC title

• H02H7/26 Primary

  Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured (locating faults in cables G01R31/08) · CPC title