Fault Diagnosis with Wavelet Packet Transform and Principal Component Analysis for Multi-terminal Hybrid HVDC Network

Abstract

In view of the fact that the wavelet packet transform (WPT) can only weakly detect the occurrence of fault, this paper applies a fault diagnosis algorithm including wavelet packet transform and principal component analysis (PCA) to the inverter-side fault diagnosis of multi-terminal hybrid highvoltage direct current (HVDC) network, which can significantly improve the speed and accuracy of fault diagnosis. Firstly, current amplitude and current slope are used to sample the data, and the WPT is used to extract the energy spectrum of the signal. Secondly, an energy matrix is constructed, and the PCA method is used to calculate whether the squared prediction error (SPE) statistics of various signals that can reflect the degree of deviation of the measured value from the principal component model at a certain time exceed the limit to judge the occurrence of the fault. Further, its maximum value is compared to determine the fault types. Finally, based on a large number of MATLAB/Simulink simulation results, it is shown that the PCA method using the current slope as the sampled data can detect the occurrence of a ground fault with small transition resistance within 2 ms, and identify the fault types within 10 ms, without being affected by the sampling frequency. Index Terms--Fault diagnosis, hybrid high-voltage direct current (HVDC), wavelet packet transform (WPT), principal component analysis (PCA).

Research on the Voltage Supporting Capability of Multi-VSC-HVDC Subsystems Operation Strategy to Receiving-end LCC-HVDC Network in Weak AC Grid

“…According to (7), the power flow Jacobian matrix of the hybrid three-infeed HVDC transmission system can be established [15]:…”

“…1 (b), does not rely on AC system commutation, and can independently control active and reactive power. Following the trend, more and more VSC-HVDC will be fed into the load center, forming a pattern where LCC-HVDC and VSC-HVDC are mixed and fed into the grid [6]- [7], as shown in Fig. 1 (c).…”

Application of MMC with Embedded Energy Storage for Overvoltage Suppression and Fault Ride-through Improvement in Series LCC-MMC Hybrid HVDC System

“…It is conservatively presumed that υ = 200 km/ms, and t Tri = 3.0 ms. Since the research on the fault detection methods [31] is beyond the scope of this paper, the detection time of 1.0 ms and 5.0 ms is adopted as the representative values to approximate t FD and analyze the impact of the detection time.…”

High-impedance Fault Detection Method Based on Feature Extraction and Synchronous Data Divergence Discrimination in Distribution Networks

“…These data fluctuations are often similar to the step changes at the beginning of an event. Because PCA is quite sensitive to step change, it is increasingly used in power systems, e. g., fault detection [11], [27] - [31]. However, PCA neglects PCs, which contain critical information about fault characteristics [32], and PCA cannot achieve a unique solution if the measurement matrix is not full rank [33].…”