Ensuring a stable and efficient transformer operation is very crucial task nowadays, especially with the integration of modern sensitive electrical equipment appliances down line. However, maloperation still cannot be completely avoided, particularly existence inrush current that possess similar characteristics as fault currents when occurred. Thus, this paper proposes an enhanced method for id...

Fiber optic sensors can be used to monitor deformation and/or the overall integrity of structure components. In this paper, we propose a fuzzy control theory based control principle for sensors, and design a new kind of fiber optic sensor used for Geological monitoring. In order to validate the efficiency of the designed sensor, we simulate a water inrush model in a coal mine, and observe the w...

In this paper, a differential protection schemes using fuzzy inference system (FIS) for power transformer protection is presented. First we review the concept of differential protection, and illustrate the magnetizing inrush current as they belong to the causes of the protection maloperation. Then relay logic and the algorithm that uses Discreet Fourier transformer for extraction of fundamental...

This paper presents an alternative approach using the differential logic associated to Artificial Neural Networks (ANNs) in order to distinguish between inrush currents and internal faults in the protection of power transformers. The Alternative Transients Program (ATP) has been chosen as the computational tool to simulate a power transformer under fault and energization situations. The Radius ...

In this paper we propose transformer-based solutions to several power quality problems. Elsewhere we have shown how to solve the acoustical noise emission problems. In this paper we introduce toroidal transformers with reduced inrush currents, transformers with reduced electromagnetic emissions, and other transformers useful to reduce the transfer of harmonics. With the low-inrush transformers ...

Among the most noticeable root causes of improper performance in power transformers, internal short circuit faults can be noted and if not quickly be identified and addressed in the accepted time interval, irrecoverable damages such as interruption or even collapse of the network connected to the power transformer would happen. In this contribution, three-phase transformer behaviors under magne...

This paper proposes a new method to detect transformer inside incipient fault current using transformer internal parameters to determine the inside structure of transformer at good condition or bad. A transformer model was established by Jiles– Atherton theory using measured voltage and current and the initial parameters which were found using Genetic Algorithm (GA). Then, transformer internal ...

This paper is an investigation into the high inrush current effect that emerges during energizing of drivers different circuit types loaded by light-emitting-diode (LED) strips. Two driver were analyzed—a voltage stabilization (VS) utilizing a Zener diode, and (CS) type in form integrated (IC). Inrush waveforms calculated for various numbers LEDs. In frame study, analysis executed energized div...