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Results of the investigations of the turn of meander microstrip delay line in the frequency domain are presented. Computational and full-scale experiments were used as the methods for investigation. Firstly, the results of the preliminary optimization of the geometrical parameters of the turn for the matching with measuring channel are presented. Secondly, the simulation of the frequency dependence...
The conversion of existing three phase double circuit transmission line into Six phase transmission line will bridge the gap between power generation and power demand. As the Six Phase system can be considered as two mutually coupled Three Phase Systems, hence the protection scheme applicable for Three Phase Transmission Line will work for Six Phase Transmission system without any change. In this...
DC community and residential microgrids are recognized as effective means for electrification of remote areas as a result of monumental efforts in many parts of the world — most significantly in India — but also through similar efforts in Nepal, Cameroon, New Guinea and Nigeria. So far modular approaches have been developed that enable construction of scalable microgrids based on PV and battery storage...
The introduction of Space division multiplexing (SDM) in optical networks brings new challenges for protection of networks since a lightpath can span multiple cores. In this paper, we investigate the problem of dynamic protection against two simultaneous failures in spacial division multiplexing elastic optical networks. For that, we propose a new path-protection sharing spectrum and straddling p-cycle...
DC protection is designed based on the DC system and its fault features. DCCB based or converter based protection solutions are different in protective devices and protection coordination methods. Equivalent inductances can be used to estimate DC fault features and the mutual impacts between the protection and system design. Fast fault interruption is essential and critical to DC distribution protection...
Due to the growth of the number and volume of accumulated documents, there arises the problem of storing documents, as well as their safe use and transmission by means of internal LANs of enterprises and the Internet. Existing ways to reduce the size of documents do not provide the necessary efficiency of document storage. Using the lexicological synthesis can significantly reduce the size of documents,...
Fault current limiters (FCLs) are one class of solutions to cope with the upcoming challenges in microgrid protection. Considering high penetration of distributed generations (DGs) in microgrids, the necessity of designing cheap and effective FCL is getting higher. This paper attempts to fill this gap by proposing an embedded FCL operating based on modifying the secondary control of DGs. As this method...
DC fault protection is one of the biggest challenge to multi-terminal direct current (MTDC) systems, because DC current has no natural zero crossing point. To overcome this problem, hybrid DC circuit breaker (DCCB), which serves as a promising solution to the isolation of DC faults, has been developed. However, hybrid DCCB contains a huge number of power semiconductors, which is costly and inefficient...
The objective of this work is to study and design a solar inverter, of a power of exit of environ 500 VA with a tension of entry of 12 VDC and an exit has purely sinusoidal wave of 230 VAC at a frequency of 50 Hz. The improvements made to the inverter are primarily at the level of the order, with first of all, the generation of a purely sinusoidal wave, but also the monitoring of the tension of entry...
A fast overcurrent protection scheme was developed for GaN gate injection transistors (GITs), harnessing the relationship between the externally measured vgs and id in steady-state operation. This relationship has been characterized in both static and dynamic testing over a wide range of operating conditions, and a circuit has been constructed to implement this control scheme. The circuit uses analog...
In order to study the ability of the ferrite magnetic ring to combined protection to the high altitude electromagnetic pulse (HEMP) and lightning, this paper studies the HEMP and lightning protection of ferrite magnetic ring based on an 500 kV open-type substation by experiment of PSCAD program. The results show that the ferrite magnetic ring can suppress the magnitude of the intrude current, effectively...
Phaser measurement unit (PMU) is one of the key components in present wide area monitoring, protection, and control systems (wAMPAC). There are delays in PMU measurements due to the delay in PMU signal acquisition that may affect the performance of applications in real time in the grid. In this paper, in order to mitigate the effect of signal acquisition delays, a predicting model of PMU is proposed...
Micro-grid is defined as a local power network with distributed energy resources (DERs) as micro-power sources scattered throughout the supply area. For reliable and short range transmission of power, micro-power sources are controlled as standalone as well as grid-synchronized power sources. The idea is to design a resilient, efficient and cost effective infrastructure based on advanced communication...
Recognizing that line-to-ground (L-G) faults are the most likely type of faults to occur, many industrial power systems are equipped with resistance grounded neutrals (NGR) to limit L-G fault currents. Limiting, identification and isolation of L-G fault currents prevents the progression of L-G faults into multiple phase faults with large fault currents and considerable damage to power systems. Under...
Protection of electronic equipment against ultrashort pulses by meander lines is considered. The results of cross-section parametric optimization and experimental investigations of a meander line turn with broad-side coupling are presented. As the result of the optimization, the set of parameters is obtained for the line per-unit-length modal delays difference maximization with the geometric mean...
This paper presents a novel voltage-based protection element using MODWT wavelet coefficients. This helps improve the sensitivity of existing current-based protection which can be subjected to sensitivity issues given the evolving distribution grids with multiple generation sites. The analysis of the voltage transient immediately after a disturbance can provide much useful information about the nature...
The implementation of the substation automation system of the 69 kV S/S Azogues 2 was conceived as a multi-vendor IEC 61850 solution using equipment from different manufacturers. Unexpectedly, the integration that should have been relatively easy became a complicated task and it was shown during the execution of the project that the IEC 61850 standard is not applied equally by all the vendors causing...
Voltage Source Converters (VSC) are becoming more common in modern High Voltage DC (HVDC) transmission systems. One of the major challenges in a multi-terminal VSC-HVDC is protection against DC side faults. Two major designs, namely, the hybrid DC breaker and the assembly HVDC breaker, are compared for operational behavior, speed of operation and current carrying capability. The Dual Modular Redundancy...
Criteria that establish protection requirements for Class 1E power systems and equipment are prescribed in this standard. The purpose of and the means for obtaining protection from electrical and mechanical damage, or failures that can occur within a time period that is shorter than that required for operator action, are described. Testing and surveillance requirements are included. Plant physical...
For the construction of the smart grid, protection needs to be accurately measured, and the current transformer needs to correctly transfer the transient process. The transient process of nonlinear ferromagnetic elements mainly includes the transformer inrush current and CT saturation. Differential protection misoperation is rarely caused by a single factor. It involves the coupling effect between...
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