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In this study a mathematical analysis for estimating the performance rate "RP" of wheel type trenching machine was studied. The mathematical analysis quantifies the analysis and resulted in an equation. This mathematical equation was checked under different operating conditions. The practical study of the performance rate showed that the deviation of the theoretical performance rate from the actual performance rate ranged from 5 to 7% for the 60.4 and 90.5 cm trench depth, respectively. The machine field efficiency also ranged between 43 and 50.1% for 90.5 cm and 60.4 cm trench depth respectively [ABSTRACT FROM AUTHOR]

Distributed Energy Resources (DERs) have disrupted the traditional electrical system. Grid-connected photovoltaic (PV) systems deliver electric energy closer to the consumer, shifting the paradigm from centralized to distributed generation. The impact of the stochastic PV output power gives rise to potentially rapid voltage fluctuations. Reactive power compensation is needed to regulate the voltage profile to meet the relevant standards. Traditional approaches like switched capacitors cannot provide reactive power that is continuously adjustable at short time scales. This paper examines an alternative distribution static synchronous compensator (D-STATCOM) based on a matrix converter (MC) for the low voltage distribution networks with high PV penetration. This technology can extend service life by using inductors for energy storage. The converter being studied provides ancillary services, including reactive power support; the impact on reliability, operational constraints, and electrical behavior is demonstrated. The contribution of this paper is a detailed analysis and impact study of the capacitor-less D-STATCOM in high PV penetration distribution networks. The significance of this paper is that it studies the behavior of the power electronics converter and its interaction with the power systems without assuming or neglecting details of either. Compensation effects and reliability comparisons between the proposed capacitorless D-STATCOM and the incumbent D-STATCOM technology are also studied in this paper.

A system is proposed to locate faults on transmission lines using the traveling wave phenomenon. Prony method is used to analyze the voltage or current signal at the local bus and extract its modal information. This information represents the traveling wave generated by the fault and can be used to estimate its location. Artificial Neural Networks (ANNs) are used to estimate the fault location based on the modal information. Two schemes are presented; the first with a voltage input signal and the second with a current input signal. Training and testing data are obtained by ATP-EMTP simulations. Tests were done to study the effect of fault resistance variation and fault incidence angle on both schemes. The system has the advantages of utilizing single-end measurements, using either a voltage or current signal; no pre-fault data is required. Index Terms--Fault location, neural networks applications, power system protection, Prony method, traveling waves.

Electrical insulation performance of compressed Gas Insulated Switchgear (GIS) and Gas Insulated Transmission Line (GITL) systems is adversely affected by metallic particle contaminants. Dielectric coatings applied to the inside surface of the outer enclosure of a coaxial GIS/GITL system improve the insulation performance in several ways. Coating has the effect of smoothing the electrode surface and reducing the prebreakdown current in the gas gap. Also, the electrostatic charge acquired by a particle is reduced and hence the range of its motion under an applied power frequency field is inhibited. The movement of such particles is complex and dependent on several parameters. In this paper the dynamics of wire particles in a coaxial system under AC voltage is studied when the inside surface of the outer enclosure of a coaxial GIS/GITL system is coated with a high resistance material. Suggestions for reducing the particle excursion in GIS/GITL systems are discussed. Index Terms--Compressed gas insulated systems, dielectric coated electrodes, particle movement.