The present disclosure pertains to systems and methods for monitoring traveling waves in an electric power system. In various embodiments, a data acquisition subsystem may acquire electric power system signals. A traveling wave detection subsystem may detect two or more traveling waves based on the electric power system signals and determine a location of an event triggering the traveling waves. A traveling wave security subsystem may selectively generate a restraining signal based on the location of the event as within a blocking zone. A protection action subsystem may implement a protective action when the location is outside of a blocking zone. In various embodiments, a protective action will not be implemented for traveling waves launched from known locations of switching devices operating normally. Further, protective actions may be restrained if a magnitude of a traveling wave differs from an expected value based on a pre-fault voltage.

A mechanism for travelling wave pilot protection of a transmission line and method for receiving indications of a travelling wave from two terminals of a transmission line, wherein two terminals are time synchronized. The method includes making a trip decision based on the indications using a short trip window. An arrangement is configured to perform the disclosed method.

The invention provides a method and system for protection in response to a fault in a mixed line. The mixed line comprises two or more sections, with a first substation at a first end and a second substation at a second end. Every two consecutive sections of the mixed line are separated at a junction. The method is performed by an IED, and comprises obtaining one or more measurements of current at the first end, and one or more measurements of current at the second end. The method also comprises identifying a section of the two or more sections having the fault, by estimating a value of current for each junction and comparing the estimated value with the one or more measurements of current. In addition, the method comprises controlling a switching device based on the section identified with the fault.

A method and system is provided for locating a fault in a mixed power transmission line. The method is implemented by an Intelligent Electronic Device (IED) of the mixed line. The IED detects a travelling wave from one or more signals received from one or more measurement equipment. Thereafter, the IED identifies a line section with the fault, and generates two or more estimates for the location of the fault based on a time difference between arrival of two peaks of the travelling wave, a velocity of propagation of the travelling wave in the line section identified with the fault, and a length of one or more line sections. The IED determines the location of the fault based on a comparison of each estimate with a threshold, wherein the threshold is estimated based on the one or more signals, equivalent source impedance of each source and total line impedance.

The present disclosure pertains to systems and methods for analyzing traveling waves in an electric power delivery system. In one embodiment, a system may comprise a traveling wave identification subsystem to receive electric power system signals and identify a plurality of incident, reflected, and transmitted traveling waves. A first traveling wave may be selected from the incident and transmitted traveling waves, and a first distortion may be determined. A second traveling wave subsequent to the first traveling wave, may selected from the incident traveling waves and a second distortion may be determined. A traveling wave analysis subsystem may compare the first distortion and the second distortion and determine whether the first distortion is consistent with the second distortion. A protective action subsystem may implement a protective action based on a first determination that the first distortion is consistent with the second distortion.

The present disclosure pertains to systems and methods for detecting traveling waves in electric power delivery systems. In one embodiment, a system comprises a capacitance-coupled voltage transformer (CCVT) in electrical communication with the electric power delivery system, the CCVT comprising a stack of capacitors and an electrical contact to a first ground connection. Electrical signals from accessible portions of the CCVT are used to detect traveling waves. Current and/or voltage signals may be used. In various embodiments, a single current may be used. The traveling waves may be used to detect a fault on the electric power delivery system.

Systems and methods may mitigate risk of fire caused by an electric power system. In one embodiment, a system may include an intelligent electronic device (IED). The IED includes a communication subsystem to receive a signal from a sensor related to a condition of the electric conductor. A processing subsystem in communication with the communication subsystem may operate in at least two modes comprising a high security mode and a fire prevention mode. In the fire prevention mode, the IED may interrupt a flow of electric current based on the signal from the at least one sensor associated with the electric conductor. In the high security mode, the system may interrupt a flow of electric current based on the signal from the at least one sensor associated with the electric conductor and based on a second condition relating to the electric conductor.

A method for fault location to single-terminal traveling wave includes steps as follows. Step (a): recording a waveform of a traveling wave signal of disturbance by a traveling wave device when a line disturbance occurs. Step (b): performing a phase mode transformation on the waveform recorded by the step (a), so as to obtain components of line mode and zero mode of a fault initial traveling wave, and performing a wavelet transform to decompose the components of the line mode to obtain singularities in the waveform of the traveling wave. Step (c): calculating a wavefront slope k of the components of the line mode of the fault initial traveling wave. Step (d): computing a preliminary fault distance D according to the slope k computed in the step (c). Step (e): confirming a fault point according to the preliminary fault distance and wavelet singularities of the components of the line mode. Step (f): end.

A method detects a fault on a line of an electrical power supply system, in which current values are measured at the line ends of the line and the current values are used to check whether there is a fault on the line. In order to perform monitoring of the line such that faults can be detected comparatively quickly and sensitively, it is proposed that voltage values are also measured at the line ends. The respective measured current and voltage values are used to ascertain respective comparison current values indicating the current flowing at a comparison location on the line and the respective comparison current values are used to check for the presence of a fault on the line, and a fault signal is generated if the check has resulted in a fault present on the line being detected.

The present disclosure pertains to systems and methods to detect faults in electric power delivery systems. In one embodiment, a data acquisition system may acquire a plurality of electric power delivery system signals from an electric power transmission line. A traveling wave system may detect a traveling wave based on the plurality of electric power delivery system signals received from the data acquisition system. The traveling wave may be analyzed using a first mode to determine a first mode arrival time and using a second mode to determine a second mode arrival time. A time difference between the first mode arrival time and the second mode arrival time may be determined. A fault location system may estimate or confirm a location of the fault based on the time difference. A protection action module may implement a protective action based on the location of the fault.