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Go to Editorial ManagerPower transformer protective relay should block the tripping during magnetizing inrush and rapidly operate the tripping during internal faults. Recently, the frequency environment of power system has been made more complicated and the quantity of 2nd frequency component in inrush state has been decreased because of the improvement of core steel. And then, traditional approaches will likely be maloperated in the case of magnetizing inrush with low second harmonic component and internal faults with high second harmonic component. This paper proposes a new relaying algorithm to enhance the fault detection sensitivities of conventional techniques by using a fuzzy logic approach. The proposed fuzzy-based relaying algorithm consists of flux-differential current derivative curve, harmonic restraint, and percentage differential characteristic curve. The proposed relaying was tested with MATLAB simulation software and showed a fast and accurate trip operation.
Since recent societies become more hooked into electricity, a higher level of power supply continuity is required from power systems. The expansion of those systems makes them liable to electrical faults and several failures are raised due to totally different causes, like the lightning strike, power system element failure caused by mechanical aging as well as human mistakes. These conditions impact the stability of the power as well as lead to costly maintenance and loss of output. This article examines the latest technologies and strategies to determine the location of faults in medium voltage distribution systems. The aim is to classify and assess different strategies in order to determine the best recommended models in practice or for further improvement. Several ways to locate failures in distribution networks have therefore been established. Because faults are unpredictable, quick fault location as well as isolating are necessary to reduce the impact of faults in distribution networks as well as removing the emergency condition from the entire system. This study also includes a comprehensive evaluation of several defect location methods depending on the algorithm employed, the input, the test system, the characteristics retrieved, and the degree of complexity. In order to gain further insight into the strengths and limitations of each method and also comparative analysis is carried out. Then the main problems of the fault location methods in distribution network are briefly expounded.
Engineers are searching for alternatives to conventional energy sources to address the energy crisis as a result of the sharp increase in energy usage. This work describes developing, simulating, and evaluating a three-phase, 13.25 kW solar power system. PV analysis is also performed. An inverter featuring a dual Electricity flow is connected to a solar system consisting of six consecutive strings of four solar power cells connected in series. The output of the phase lock loop (PLL) feedback in the linearization system is used to generate a signal, and the power conversion voltage is synchronized with the signal by using its output as a voltage reference. This hybrid technology, which has two phases that are optimal for the rechargeable recharging process of the batteries, is used to replenish a battery bank in capacity or float arrangement for eight sequences of 12V - 200-Ah rechargeable batteries. Ultimately, a MATLAB computational model has been created for a grid-connected photovoltaic system that uses sinusoidal modulation of pulse width and an inverter as voltage sources.