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This paper proposes a novel approach for fault detection, classification, and distance estimation of five kinds of faults (ie, cable and Arc faults) in the PV‐based DC‐ring microgrid. The proposed approach is based on the Hilbert Huang Transform (HHT) and online sequential random vector functional link network (OS‐RVFLN). Initially, differential current signals are passed through empirical mode decomposition (EMD) to yield intrinsic mode functions (IMFs). Among the series of IMFs, more efficient IMFs are selected based on the threshold of maximum weighted kurtosis index (M‐WKI) value for fault diagnosis. The selected IMFs are passed through Hilbert transform (HT) for determining the instantaneous frequency, magnitude spectrum, and Hilbert energy. Then, the Teager energy operator (TEO) is applied to the more effective IMF among the selected IMFs of each DC fault for fault detection. The most suitable target features are extracted from the selected efficient IMFs. This feature set data is initialized to the proposed HHT‐OSRVFLN algorithm for five kinds of faults classification and its location estimation. The performance of the proposed algorithm in the proposed microgrid is proved in terms of low fault detection time, superior classification accuracy, and low relative error through different case studies by consuming minimum computation time in MATLAB/Simulink environment. Finally, the digital architecture of the proposed method is designed and simulated in Xilinx ISE 14.5 software environment to estimate the fault location. The Chip scope hardware debugging output proves the correctness, simplicity, feasibility, practicability, and robustness of the proposed method for online fault diagnosis. [ABSTRACT FROM AUTHOR]

In this article, self-adaptive variational mode decomposition (SAVMD), deep convolutional neural networks (DCNN), and online-sequential random vector functional link networks (OSRVFLN) are integrated to categorize the single as well as combined power quality events (PQEs) in real time. The SAVMD method is proposed to optimize both the number of decomposition and data-fidelity factor to extract the most efficient band-limited mode (BLM) based on entropy and Kurtosis index. The most discriminative unsupervised features are extracted automatically using a DCNN from the BLM of SAVMD. The extracted distinct feature vector is fed to the proposed supervised OSRVFLN classifier to train accurately by minimizing the training cross-entropy loss with an increment in the number of hidden nodes for obtaining the maximum classification accuracy of the complex PQE patterns in noisy and noise-free environments. The automatic efficacious feature extraction, superior classification accuracy, noise immunity, and short event detection time are the major advantages of the proposed SAVMD-DCNN-OSRVFLN method. Finally, the novel methodology is implemented in a fast digital Xilinx Virtex-5 field-programmable gate array embedded processor to validate the practicability and feasibility of the proposed method in real-time. [ABSTRACT FROM AUTHOR]

This study proposes an improved hybrid model built with empirical mode decomposition (EMD) features combined with weighted multi‐kernel random vector functional link network (WMKRVFLN) where the kernel parameters are optimised with an efficient optimisation algorithm known as water cycle algorithm (WCA) for diagnosis and classification of epileptic electroencephalogram (EEG) signals. The proposed model with optimisation is known as WCA–EMD–WMKRVFLN. The tanh and wavelet kernel functions are contributing together to the effectiveness of the proposed model. The features generated from EMD in terms of intrinsic mode functions (IMFs) are modulated to find important statistical and entropy based features and these features in a reduced form are employed as inputs to the model to classify epileptic EEG signals. The presented approach is evaluated in terms of percentage correct classification accuracy (ACC), specificity and sensitivity using two datasets and is compared with different classifiers and state‐of‐the‐art techniques. The highest accuracies of 99.69% (five‐class) and 100% (three‐class) achieved using the Bonn‐University dataset and 99.0% ACC (two‐class) achieved using the Bern‐Barcelona dataset. The achieved results report that the presented approach is a promising approach for EEG signal classification and is superior to several state‐of‐the‐art techniques and is highly comparable to many such techniques. [ABSTRACT FROM AUTHOR]

In this paper, Hilbert Huang transform (HHT) and weighted bidirectional extreme learning machine (WBELM) are integrated to detect and classify power quality events (PQEs) in real time. Empirical mode decomposition is used to decompose the nonstationary PQEs into the monocomponent mode of oscillation, known as intrinsic mode functions (IMFs). The efficacious features are extracted by applying the Hilbert transform (HT) on the IMFs. An efficient WBELM computational intelligence technique is proposed to recognize the single, as well as multiple PQEs and its performances are compared with the recently developed classifiers such as support vector machine, least-square support vector machine, extreme learning machine, and bidirectional extreme learning machine. The recognition architecture of HHT integrated with WBELM (HHT-WBELM) method is tested and compared with the empirical wavelet transform associated with HT and WBELM method, and tunable-Q wavelet transform along with HT and WBELM method. The faster learning speed, lesser computational complexity, superior classification accuracy, and short event detection time prove that the proposed HHT-WBELM method can be implemented in the online power quality monitoring system. Finally, a hardware prototype is developed based on the digital signal processor to verify the cogency of the proposed method in real time. The feasibility of the proposed method is tested and validated by both the simulation and laboratory experiments. [ABSTRACT FROM AUTHOR]