Investigation and Optimization of Grounding Grid Based on Lightning Response by Using ATP-EMTP and Genetic Algorithm

A large number of electromagnetic transient studies have been analyzed for finding the overvoltage behavior of power system. A grounding grid of power system is so important for reducing the effect of overvoltage phenomena during a short-circuit event. Two sections are important in grounding system behavior: soil ionization and inductive behavior; this paper focuses on the inductive manner of grounding grid. The grounding grid is considered as a conductor segment; each conductor segment acts as a grounding unit. In this paper, the transient methodology is introduced to investigate the lightning effect on grounding body at each point of grounding grid in normal and optimized conditions. Genetic algorithm is applied for regular and irregular grounding grid to obtain best values of mesh size with the lower ground potential rise (GPR) as compared with the normal condition for more safety. The grounding grid is a combination of inductance, resistance, and capacitance. This model is suitable for practical applications related to fault diagnosis. Several voltages on different positions of grounding grid are described in this paper using ATP-EMTP and genetic algorithm. The computer simulation shows that the proposed scheme is highly feasible and technically attractive.

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Experimental Investigation of Surge Propagation Characteristics on a Substation Grounding System

Journal of Physics Conference Series ◽

10.1088/1742-6596/2096/1/012113 ◽

2021 ◽

Vol 2096 (1) ◽

pp. 012113

Author(s):

V V Kolobov ◽

M B Barannik ◽

V V Ivonin

Keyword(s):

Wave Propagation ◽

Transmission Lines ◽

Propagation Velocity ◽

Electromagnetic Waves ◽

Mesh Size ◽

Correct Choice ◽

Residual Voltage ◽

Grounding System ◽

Grounding Grid ◽

Current Wave

Abstract With the correct choice of the arrester by voltage class and compliance with the calculated protective distance without taking into account the propagation velocity of the current wave on the grounding grid, overvoltages exceeding discharge or residual voltage may occur on the protected equipment, in particular the transformer. Thus, when calculating the installation of the arrester that protects the substation from incoming lightning surges from a transmission lines, it is necessary to take into account the propagation of the current wave on the grounding grid. The propagation velocity of electromagnetic waves in a 150 kV substations grounding grid was measured. The measured wave propagation velocities are in the range of 50–100⋅106 m/s. Thus, the obtained velocity of wave propagation on the grounding grid used in service is several times less than the speed of light. The measured value correlates well with similar experiments conducted for buried conductors located in soils with similar parameters and the results of mathematical modeling for a grounding grid having similar dimensions and mesh size.

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A GENETIC ALGORITHM-BASED APPROACH FOR THREE-PHASE FAULT EVALUATION IN A DISTRIBUTION NETWORK

International Journal of Computing ◽

10.47839/ijc.19.3.1891 ◽

2020 ◽

pp. 418-433

Author(s):

Chikomborero Shambare ◽

Yanxia Sun ◽

OdunAyo Imoru

Keyword(s):

Genetic Algorithm ◽

Power System ◽

Short Circuit ◽

Distribution Network ◽

Basic Information ◽

Scaling Factors ◽

Evaluation Procedures ◽

Three Phase ◽

Nominal Voltage

Standard IEC 60909 provides all the basic information that is used in the evaluation of three-phase short circuit faults. However, it uses numerous estimations in its fault evaluation procedures. It estimates voltage factors, resistance to reactance ratios (R/X), resistance to impedance ratios (R/Z) and other scaling factors. These estimates do not cater for every nominal voltage. Users often have to approximate these values. In this paper, adjustments were made to the genetic algorithm (GA) with regards to gene replacements and arrangement of scores and expectation. During fault computation, the GA was used to stochastically determine R/X and R/Z ratios with regards to the parameters of the power system. The GA was tested on a nominal voltage that is properly catered for by Standard IEC. The GA results and the IEC values were within an approximate range. This implies that the developed GA can be further used to determine these ratios for nominal voltages that are not sufficiently accounted for by Standard IEC. This leads to obtaining precise fault values in all instances.

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Design and Experimental Study of a Novel Fault Current Limiter

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.139-141.1839 ◽

2010 ◽

Vol 139-141 ◽

pp. 1839-1842 ◽

Cited By ~ 2

Author(s):

Chun Zhao ◽

Jia Zheng Lu ◽

Zheng Long Jiang ◽

Zhen Fang ◽

Bo Li

Keyword(s):

Power System ◽

High Speed ◽

Short Circuit ◽

Short Circuit Current ◽

Fault Current ◽

Fault Current Limiter ◽

Vacuum Switch ◽

System A ◽

Active Transfer ◽

Current Limiter

Limiting the short-circuit current effectively is of great importance to keep the safe and steady running of the power system. A novel fault current limiter (FCL) on the basis of a high speed switch and a triggered vacuum switch (TVS) is presented. The high speed switch is used to break the short-circuit current of the power system. The TVS is used to discharge the precharged pulse capacitor so as to rapidly extinguish the arc in the high speed switch and to realize the active transfer of the short-circuit current. A resistor is used to limit the short-circuit current. The parameters of the FCL for the 10 kV power system are designed and a FCL apparatus is fabricated. An onsite experiment of the FCL apparatus is performed in an actual transmission line of a substation. The FCL apparatus operates normally and achieves the expected current limiting effect.

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Effect of transmission switching and short circuit on the transient stability at interconnected power system: A case study of 150 kV Mahakam East Kalimantan electrical power system

10.1063/1.5098210 ◽

2019 ◽

Author(s):

Chico Hermanu ◽

Edi Nugroho ◽

Irwan Iftadi

Keyword(s):

Power System ◽

Transient Stability ◽

Short Circuit ◽

Electrical Power ◽

Electrical Power System ◽

Interconnected Power System ◽

Transmission Switching ◽

East Kalimantan ◽

System A

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Vulnerability Assessment of Power Systems to Intentional Attacks using a Specialized Genetic Algorithm

DYNA ◽

10.15446/dyna.v82n192.48578 ◽

2015 ◽

Vol 82 (192) ◽

pp. 78-84 ◽

Cited By ~ 3

Author(s):

Laura Agudelo ◽

Jesús María López-Lezama ◽

Nicolás Muñoz Galeano

Keyword(s):

Genetic Algorithm ◽

Power Systems ◽

Power System ◽

Terrorist Attack ◽

Test System ◽

Reliability Test ◽

Terrorist Threat ◽

Critical Elements ◽

System A ◽

System Operator

<p class="Abstract"><span lang="EN-US">A specialized genetic algorithm applied to the solution of the electric grid interdiction problem is presented in this paper. This problem consists in the interaction of a disruptive agent who aims at maximizing damage of the power system (measured as load shed), and the system operator, who implements corrective actions to minimize system load shed. This problem, also known as “the terrorist threat problem”, is formulated in a bilevel programming structure and solved by means of a genetic algorithm. The solution identifies the most vulnerable links of the network in terms of a terrorist attack, providing signals for future reinforcement of the network or more strict surveillance of critical elements. The proposed approach has been tested on three case studies: a didactic five-bus power system, a prototype of the Colombian power system and the IEEE Reliability Test System. Results show the robustness and applicability of the proposed approach.</span></p>

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The Development of a Graphical Open-Ended Integrative Platform for Short-Circuit Calculation and Relay Setting of Power System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.241-244.1802 ◽

2012 ◽

Vol 241-244 ◽

pp. 1802-1811

Author(s):

Zhi Bo Li ◽

Peng Gao ◽

Jian Sheng Ma ◽

Yong Sheng Yan

Keyword(s):

Power System ◽

Short Circuit ◽

Short Circuit Current ◽

Simulation Software ◽

Target System ◽

Practical Applications ◽

Short Circuit Calculation ◽

Topology Information ◽

Current Calculation ◽

Report Document

To improve the efficiency and accuracy of relay setting calculation of power system, this paper proposed and developed a schematized and open-ended software platform in integrative relay setting. Through the advanced development of the Visio software, the graphical input of the target system topology and component parameters are made possible. The platform can automatically generate PSCAD simulation model according to the topology information and device parameters through an interface program to PSCAD, and use this power system simulation software to improve the accuracy of short-circuit current calculation. With the help of the Bookmark mechanism of WORD software, the platform provides a setting template with general protection components, which forms the basis to realize the open-ended platform. The platform also uses the API interface provided by WORD software to automatically generate the final relay protection setting report document according to the results of short-circuit current calculation and the selected protection setting components. This paper gives in detail the overall framework of the proposed platform, as well as the principle and practice of all the above parts. Moreover, the validity and practicality in improving the automation degree of the relay setting of power plant are shown through practical applications.

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