G01R31/088

SYSTEMS AND METHODS FOR HIGH IMPEDANCE FAULT DETECTION IN ELECTRIC DISTRIBUTION SYSTEMS
20230048196 · 2023-02-16 ·

Systems, methods, and computer-readable media are disclosed for high impedance detection in electric distribution systems. An example method may include calculating, by a processor, a relative randomness of a signal, wherein the relative randomness is a derivative of a first scale wavelet transform divided by an energy of the signal. The example method may also include calculating, by the processor, one or more scales of a wavelet transform of the signal. The example method may also include calculating, by the processor, one or more energy ratios between energy of the wavelet transform in the one or more scales. The example method may also include calculating, by the processor, a zero-crossing phase difference between a third harmonic and a fundamental component of the signal. The example method may also include determining, by the processor, that a high impedance fault occurs based on at least one of: the relative randomness, a comparison between the one or more scales of the wavelet transform, and the zero-crossing phase difference.

Systems and methods for managing energy-related stress in an electrical system
11579647 · 2023-02-14 · ·

A method for reducing and/or managing energy-related stress in an electrical system includes processing electrical measurement data from or derived from energy-related signals captured by at least one intelligent electronic device (IED) in the electrical system to identify and track at least one energy-related transient in the electrical system. An impact of the at least one energy-related transient on equipment in the electrical system is quantified, and one or more transient-related alarms are generated in response to the impact of the at least one energy-related transient being near, within or above a predetermined range of the stress tolerance of the equipment. The transient-related alarms are prioritized based in part on at least one of the stress tolerance of the equipment, the stress associated with one or more transient events, and accumulated energy-related stress on the equipment. One or more actions are taken in the electrical system in response to the transient-related alarms to reduce energy-related stress on the equipment in the electrical system.

FAULT POINT LOCATING DEVICE AND METHOD, ELECTRIC POWER SYSTEM MONITORING SYSTEM, AND FACILITY PLANNING SUPPORT SYSTEM
20180011136 · 2018-01-11 ·

A fault point locating device which estimates a fault point in an electric power system, is provided with: a variation range calculating means which obtains a range of variation of sensor values and a range of variation of an impedance of the electric power system, on the basis of the sensor values, which include measured voltage values and measured current values before and after the fault and which are measured using sensors installed in the electric power system, sensor errors representing error ranges of the sensors in relation to the sensor value measurements, said impedance, and an impedance variation parameter for determining the range of variation of the impedance; a combination creating means which creates combinations of values that the sensor values and the impedance value could attain; and a fault point locating means which calculates a fault point range representing distances from the sensors to the fault point.

Systems and methods for high impedance fault detection in electric distribution systems

Systems, methods, and computer-readable media are disclosed for high impedance detection in electric distribution systems. An example method may include calculating, by a processor, a relative randomness of a signal, wherein the relative randomness is a derivative of a first scale wavelet transform divided by an energy of the signal. The example method may also include calculating, by the processor, one or more scales of a wavelet transform of the signal. The example method may also include calculating, by the processor, one or more energy ratios between energy of the wavelet transform in the one or more scales. The example method may also include calculating, by the processor, a zero-crossing phase difference between a third harmonic and a fundamental component of the signal. The example method may also include determining, by the processor, that a high impedance fault occurs based on at least one of: the relative randomness, a comparison between the one or more scales of the wavelet transform, and the zero-crossing phase difference.

Method and Apparatus for Sensor Measurements Processing

Various embodiments of the teachings herein include methods, apparatuses, and computer-readable storage media for sensor measurements processing. An example method 100 includes: getting (S101) measurements by a group of sensors; estimating (S102) initial true states of the physical processes; and repeating the following until convergence: calculating (S103) reliability scores of the group of sensors such that a more reliable sensor should be more likely to provide measurements which are closer to real state of the physical process monitored by the sensor; and estimating (S104), based on the calculated reliability scores, true states of the physical processes, such that the real state of a physical process should be closer to measurements by a more reliable sensor.

VECTOR ANALYSIS CALCULATION-BASED ARC CROSSTALK SIGNAL IDENTIFICATION METHOD

A vector analysis calculation-based arc crosstalk signal identification method. A new sampling circuit manner is proposed in the method, wherein a current signal is sampled on zero and live lines, and the signal is converted into two digital signals with a sampling rate of 200 MHz by means of a dual-channel ADC, and the digital signals are sent to a hardware digital signal processing unit. Five pass bands are selected to perform band-pass filtering on the two signals separately. Time-sharing processing and vector analysis are performed on the filtered signals, and the amplitude ratio and fluctuation characteristics of two resistor terminal voltages, as well as the phase difference between shunt resistor and inductor terminal voltage signals are extracted as crosstalk feature quantities. According to a zero-crossing signal, a system segments the feature quantities extracted by a hardware processing module and sends same to a neural network for classification and determination.

CABLE DETERIORATION DIAGNOSIS DEVICE, CABLE DETERIORATION DIAGNOSIS METHOD, AND PROGRAM
20230028876 · 2023-01-26 ·

A cable deterioration diagnosis device configured to diagnose deterioration of a cable having a plurality of electrical wires including one or more signal wires configured to transmit signals between a first device and a second device, and includes a test signal output unit configured to output a wave-like test signal to a test signal transmitting wire independent of the one or more signal wires among the plurality of electrical wires, a test signal extraction unit configured to extract a received test signal corresponding to the test signal from a signal propagated in a test signal receiving wire independent of the one or more signal wires and the test signal transmitting wire among the plurality of electrical wires, and a deterioration detection unit configured to detect the deterioration of the cable based on the test signal and the received test signal.

METHOD FOR PROTECTING DC LINE IMPEDANCE PHASE BASED ON PROTECTION AND CONTROL COORDINATION

The present disclosure relates to a method for protecting DC line impedance phase based on protection and control coordination, and an application scenario of the method for protecting is a three-terminal flexible DC transmission network. The method uses high controllability of a converter after a fault, injects a characteristic signal at a characteristic frequency, and calculates a phase angle of input impedance to determine a fault interval, which effectively improves protection performance, turns passive to active, and is not affected by nonlinearity of the converter. At the same time, compared with a full-bridge MMC, using a half-bridge MMC does not need to perform fault ride-through first when identifying a fault, and does not need to add additional equipment, it creates fault features and can reliably identify an fault interval; improves protection quickness and at the same time also has better economic benefits. It has selectivity, and an entire system may not be shut down due to failure of a single line.

Determining of a power line fault
11703534 · 2023-07-18 · ·

A method of determining a fault in a protected zone of a power line comprises obtaining measurements at a measurement point at one end of the power line, processing the measurements in a number of parallel processing branches comprising at least two parallel processing branches, wherein the processing in each branch comprises filtering the measurements in a corresponding low pass filter for obtaining a corresponding set of filtered measurements, wherein the cut-off frequencies of the low pass filters in these parallel processing branches differ from each other, performing reach calculations on the filtered measurements for obtaining corresponding reach point quantities, and comparing the reach point quantities with corresponding thresholds. Finally, it is determined that there is a fault within the protected zone if any threshold is crossed.

NOISE INTRUSION POSITION ESTIMATION DEVICE AND NOISE INTRUSION POSITION ESTIMATION METHOD
20230018215 · 2023-01-19 · ·

A noise intrusion position estimation device includes: a measurement unit including a pair of detection units to simultaneously measure a temporal change of waveforms of noise on a transmission cable at two separated observation points in the transmission cable; and a calculation unit to receive, from the measurement unit a pair of the waveforms of the noise simultaneously measured, to time-reverse the pair of the waveforms of the noise that has been received, to perform transmission path analysis in which the two observation points are set as positions of signal sources of the time-reversed noise and the time-reversed waveforms are set as excitation waveforms in a transmission line model in which electrical characteristics of the transmission cable are represented, and to output a position of a peak value obtained from a result of the transmission path analysis as an intrusion position of the noise into the transmission cable.