scholarly journals Direct current electric potentials for a multilayered earth with arbitrary electrode configurations—Derivation of theoretical recurrence formulas for a point current source excitation—

2010 ◽  
Vol 63 (2) ◽  
pp. 197-208
Author(s):  
Yuji Mitsuhata ◽  
Takumi Ueda
Keyword(s):  
Direct Current ◽  
Current Source ◽  
Recurrence Formulas ◽  
Electric Potentials ◽  
Source Excitation

scholarly journals Active Cloaking and Illusion of Electric Potentials in Electrostatics

2021 ◽  
Author(s):  
Andreas Helfrich-Schkabarenko ◽  
Alik Ismail-Zadeh ◽  
Aron Sommer
Keyword(s):  
Electric Potential ◽  
Superposition Principle ◽  
Current Source ◽  
Three Dimensional ◽  
Numerical Results ◽  
Research Fields ◽  
Electric Potentials ◽  
Three Dimensional Models ◽  
First Time ◽  
A Current

Abstract Cloaking and illusion has been demonstrated theoretically and experimentally in several research fields. Here we present for the first time an active exterior cloaking device in electrostatics operating in a two-horizontally-layered electroconductive domain, and use the superposition principle to cloak electric potentials. The device uses an additional current source pattern introduced on the interface between two layers to cancel the total electric potential to be measured. Also, we present an active exterior illusion device allowing for detection of a signal pattern corresponding to any arbitrarily chosen current source instead of the existing current source. The performance of the cloaking/illusion devices is demonstrated by three-dimensional models and numerical experiments using synthetic measurements of the electric potential. Sensitivities of numerical results to a noise in measured data and to a size of cloaking devices are analysed. The numerical results show quite reasonable cloaking/illusion performance, which means that a current source can be hidden electrostatically. The developed active cloaking/illusion methodology can be used in subsurface geo-exploration studies, electrical engineering, live sciences, and elsewhere.

Study on interference and protection of pipeline due to high-voltage direct current electrode

2019 ◽  
Vol 37 (3) ◽  
pp. 273-281 ◽  
Author(s):  
Yang Chao ◽  
Li Jianliang ◽  
Li Zili ◽  
Zhang Shouxin ◽  
Dai Long ◽  
...  
Keyword(s):  
High Voltage ◽  
Direct Current ◽  
Cathodic Protection ◽  
Current Source ◽  
Buried Pipelines ◽  
Stray Current ◽  
Current Electrode ◽  
Protective Measures ◽  
High Voltage Direct Current ◽  
Pipe Section

AbstractTo study the rules of interference and protective measures on buried pipelines of high-voltage direct current (HVDC), the influence of different factors, including current into soil, soil resistance, damaged rate of coatings, and electrode-to-pipe distance, on pipe-to-soil potential deviation were simulated. Based on the simulated results, the fitted equations and interference judgment pattern were also obtained. The protective measures of insulation and cathodic protection can be performed for buried pipelines to prevent the interference, but the cathodic protection in the isolated area may become the stray current source of the other pipe section. This study can provide suggestions for the evaluation of interference and protective measures of pipelines of HVDC.

scholarly journals Dynamic Modeling of HVDC for Power System Stability Assessment: A Review, Issues, and Recommendations

Energies ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4829
Author(s):  
Tarek Abedin ◽  
M. Shahadat Hossain Lipu ◽  
Mahammad A. Hannan ◽  
Pin Jern Ker ◽  
Safwan A. Rahman ◽  
...  
Keyword(s):  
Steady State ◽  
Dynamic Modeling ◽  
Direct Current ◽  
Current Source ◽  
Computational Cost ◽  
Operating Conditions ◽  
System Stability ◽  
Voltage Source ◽  
Voltage Source Converter ◽  
Stability Assessment

High-voltage direct current (HVDC) has received considerable attention due to several advantageous features such as minimum transmission losses, enhanced stability, and control operation. An appropriate model of HVDC is necessary to assess the operating conditions as well as to analyze the transient and steady-state stabilities integrated with the AC networks. Nevertheless, the construction of an HVDC model is challenging due to the high computational cost, which needs huge ranges of modeling experience. Therefore, advanced dynamic modeling of HVDC is necessary to improve stability with minimum power loss. This paper presents a comprehensive review of the various dynamic modeling of the HVDC transmission system. In line with this matter, an in-depth investigation of various HVDC mathematical models is carried out including average-value modeling (AVM), voltage source converter (VSC), and line-commutated converter (LCC). Moreover, numerous stability assessment models of HVDC are outlined with regard to stability improvement models, current-source system stability, HVDC link stability, and steady-state rotor angle stability. In addition, the various control schemes of LCC-HVDC systems and modular multilevel converter- multi-terminal direct current (MMC-MTDC) are highlighted. This paper also identifies the key issues, the problems of the existing HVDC models as well as providing some selective suggestions for future improvement. All the highlighted insights in this review will hopefully lead to increased efforts toward the enhancement of the modeling for the HVDC system.

Artificial Insulating Joints for Stray Current Mitigative Measurements★

CORROSION ◽  
1957 ◽  
Vol 13 (10) ◽  
pp. 18-20
Author(s):  
G. H. CANTWELL
Keyword(s):  
Direct Current ◽  
Carrying Capacity ◽  
Current Source ◽  
Electrical Measurements ◽  
Stray Current ◽  
The Earth

Abstract In making electrical measurements pertinent to determining stray current mitigative measures, it is often desirable to determine the effect of a proposed insulating joint at a predetermined location. By applying a direct current source between the structure and the earth in the manner described in this paper, simulation of an insulating joint is achieved. Since the method is entirely electrical, the placing of temporary insulating joints for test purposes is eliminated. This method can be applied to any structure carrying stray DC earth currents. In addition to simulating an insulating joint, the associated current and potential measurements are used to determine (1) the resistance to earth of the structure on each side of the point of application, (2) the potential to earth that would exist on each side of a permanent insulating joint, (3) the potential across the permanent insulating joint. They also provide data for determining the resistance and current carrying capacity for a bridging resistor. 4.5.3

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