Results 11 to 20 of about 797,708 (244)

An Active Ground Fault Location Method for Low-Voltage DC Lines Based on DFFT

Zhongguo dianli, 2023
For the problem of locating ground faults in low-voltage DC cable lines containing power electronic transformers, a single-ended volume fault location method using power electronic transformers with active injection is proposed for rapid fault detection ...
Fulu CAO, Jinbin ZHAO, Chao PAN, Ling MAO, Keqing QU   +4 more
doaj   +1 more source

Shake Table Testing of Voltage and Current Transformers and Numerical Derivation of Corresponding Fragility Curves

Infrastructures, 2022
Damage to devices installed in electric substations, which have shown vulnerable behaviour under strong earthquakes in the last decades, may endanger power delivery in the emergency phases during and after an earthquake. Within seismic risk assessment of
Francesco Cavalieri, Giuseppe Donelli, Rui Pinho, Filippo Dacarro, Nunzia Bernardo, Michele de Nigris   +5 more
doaj   +1 more source

Pre-breakdown Characteristics of Contaminated Power Transformer Oil [PDF]

, 2007
In this paper we have studied pre-breakdown characteristics of transformer oil in the presence of different levels of contamination. The contaminant is fibrous dust from pressboard insulation used for high voltage transformers.
Zuber, H M, M. H. Zuber, G. Chen, Chen, G   +3 more
core   +2 more sources

Evaluation of the Accuracy and Frequency Response of Medium-Voltage Instrument Transformers under the Combined Influence Factors of Temperature and Vibration

Energies, 2023
Instrument transformers are largely used to measure voltages and currents in public electricity networks. Their performance is essential for Power Quality measurements. Tests and procedures to estimate the effect of single influence factors are performed
Mohamed Agazar, Daniela Istrate, Patrice Pradayrol   +2 more
doaj   +1 more source

On the Long-Period Accuracy Behavior of Inductive and Low-Power Instrument Transformers

Sensors, 2020
The accuracy evaluation of instrument transformers is always a key task when proper control and management of the power network is required. In particular, accuracy becomes a critical aspect when the grid or the instrumentation itself is operating at ...
Alessandro Mingotti, Lorenzo Bartolomei, Lorenzo Peretto, Roberto Tinarelli   +3 more
doaj   +1 more source

Threshold values determination in high-voltage equipment diagnosis insulation by registration methods of partial discharges [PDF]

Омский научный вестник, 2019
The paper presents theoretical information diagnosing insulation parameters of high-voltage transformers. The results of experimental studies on high-voltage transformers in the normal, pre-emergency and emergency states are shown. The comparison was
A. A. Kuznetsov, A. Yu. Kuzmenko, M. A. Kuznetsova, A. V. Simakov   +3 more
doaj   +1 more source

Single-Phase Five-Level Multilevel Inverter Based on a Transistors Six-Pack Module

Energies, 2022
This article introduces a single-phase five-level multilevel inverter based on six switches and two transformers. The proposed converter requires a single dc input source with low voltage.
Flavio A. Garcia-Santiago, Julio C. Rosas-Caro, Jesus E. Valdez-Resendiz, Jonathan C. Mayo-Maldonado, Antonio Valderrabano-Gonzalez, Hector R. Robles-Campos   +5 more
doaj   +1 more source

Variable Reactance Criteria to Mitigate Voltage Deviations in Power Transformers in Light- and Over-Load Conditions

Machines, 2023
In this paper, variable reactance (VR) criteria are proposed to mitigate voltage deviations in power transformers under light-load inductive and capacitive conditions, as well as for over-load conditions.
Marta Haro-Larrode
doaj   +1 more source

Evaluation of Lightning Impulse Test by Frequency Response Analysis [PDF]

, 2006
In this work are presented the basis for improving the interpretation of transformer lightning impulse test and the development of a graphical user interface system, which allows comparisons of time domain data and frequency response.
Jorge Ramirez, Baudilio Valecillos, Valecillos, Baudilio, Ramírez, Jorge   +3 more
core   +3 more sources

A measurements-based discharge location algorithm for plain disc winding power transformers [PDF]

, 2005
A measurements-based electrical method for locating partial discharges (PD) in transformers is described in the paper. This location method relies on the series resonance frequencies of the signals produced at the transformer terminals by a discharge on ...
Wang, Zhongdong D., Crossley, P.A., Crossley, Peter A., Hettiwatte, Sujeewa N., Hettiwatte, S.N., Wang, Z.D.   +5 more
core   +1 more source