Summary
The paper describes the design aspect and control logic of a cascaded multilevel inverter‐based shunt active filter by employing single‐phase toroidal core transformers in cascaded manner which enable to operate with a single DC‐link capacitor. The presented topology uses a single DC‐link capacitor, thus minimizing the number of sensors and controller for voltage balancing. The induction of cascaded toroidal core transformer makes the system highly reliable as it minimizes the failure possibility of the DC‐link capacitor. For reference current generation, a perfect harmonic cancelation (PHC) control technique is implemented which is insensitive to distorted input condition and frequency deviation. To verify the effectiveness of the PHC controller, it is compared with a well‐known id‐iq control technique under ideal and non‐ideal supply main conditions. Furthermore, the developed topology is validated through MATLAB simulation and its prototype along with a well‐known DSP‐based FPGA controller.
Summary
This paper describes an empirical mode decomposition control algorithm to extract the fundamental component and set the reference for harmonic extraction in a cascaded multilevel inverter–based shunt active filter. The proposed technique is fully reliant on the data samples that are decomposed instantaneously and does not require any weighing factor. The fundamental component of load current is found by applying a novel empirical mode decomposition algorithm from the nonlinear load current samples. Spline interpolation is used to extract the intrinsic mode function. For online implementation, the maxima and minima points of load current are stored using a modified field programming gate array (FPGA)‐based circular buffer circuit. Finally, the proposed cascaded multilevel inverter–based shunt active filter is investigated both by simulation and hardware implementation. The results obtained validates the performance of the proposed control technique under balanced and unbalanced loading conditions.
Fault detection and classification is a key challenge for the protection of High Voltage DC (HVDC) transmission lines. In this paper, the Teager–Kaiser Energy Operator (TKEO) algorithm associated with a decision tree-based fault classifier is proposed to detect and classify various DC faults. The Change Identification Filter is applied to the average and differential current components, to detect the first instant of fault occurrence (above threshold) and register a Change Identified Point (CIP). Further, if a CIP is registered for a positive or negative line, only three samples of currents (i.e., CIP and each side of CIP) are sent to the proposed TKEO algorithm, which produces their respective 8 indices through which the, fault can be detected along with its classification. The new approach enables quicker detection allowing utility grids to be restored as soon as possible. This novel approach also reduces computing complexity and the time required to identify faults with classification. The importance and accuracy of the proposed scheme are also thoroughly tested and compared with other methods for various faults on HVDC transmission lines.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.