Arc Grounding Fault Monitoring and Fire Prediction Method Based on EEMD and Reconstruction

Abstract

To solve the problem of the single-phase ground fault and occurrence of electrical fires due to the residual current in substation AC power systems, a residual current intelligent sensing technology is proposed based on ensemble empirical modal decomposition (EEMD), sample entropy (SE) reconstruction, and fire warning technology using a beetle antennae search algorithm. First, through the residual current monitoring device to collect residual current information, EEMD and SE reconstruction for arc-earth fault diagnosis and an analysis of the differences in the current characteristics of each line after reconstruction are used to determine the fault line. Second, residual current, temperature, and operating voltage as input parameters and fire probability are the output parameters. The input–output relationship is established by a back-propagation neural network (BPNN) and optimized by the beetle antennae search (BAS) algorithm to speed up the convergence and improve the prediction accuracy to establish a substation fire warning scheme. Through simulation experiments, this paper proposes the residual current as a monitoring object method can effectively diagnose ground faults and accurately predict the probability of fire occurrence to ensure the safe and stable operation of substations.

Improved LS-SVM Method for Flight Data Fitting of Civil Aircraft Flying at High Plateau

“…where α i ∈ R, α i > 0 is the Lagrange multiplier so the optimal solution condition is as follows (6):…”

“…Many scholars have carried out fruitful research on flight data analysis and application, mainly focusing on flight data processing, flight data application, and other application research. Flight data have many applications in aviation operation safety research [2][3][4][5][6]. Some scholars have applied flight data to turbine fault diagnosis, general aviation anomaly detection, aviation safety key landing index prediction [7][8][9][10][11], tower flight data manager man-machine system integration design processes, and new methods for nonlinear aerodynamic modeling of flight data [12][13][14].…”

Ground Fault in Medium-Voltage Power Networks with an Isolated Neutral Point: Spectral and Wavelet Analysis of Selected Cases in an Example Industrial Network Modeled in the ATP-EMTP Package

“…Due to the relatively low values of the zero-sequence currents and voltages in an isolated neutral point network, these measuring systems and protection devices are much more sensitive to disturbances and require more complex calculations and simulations taking into account transients and deformations of the zero-sequence voltages and currents caused by power electronic converters. The complexity of ground fault phenomena (especially transients and nonlinear arc resistances) drives the use of complex multiresolution digital signal processing methods based on wavelet transforms [4][5][6] and empirical mode decomposition (EMD) [7]. It should be noted, however, that despite obvious advances in the use of microprocessor technology and digital signal processing in protective relaying, practically applied protection in hazardous areas is still based on quite simple, strict, and conservative standards and regulations (like directional or nondirectional overcurrent relays or admittance relays).…”