Research on the Impact of Xiamen VSC-HVDC on the Short-circuit Current Level of the Power Grid and the Suppression Measures

Topology adjustment is a main measure to limit short circuit current, but changes of power grid structure might bring deep impact on power system operation. Measures to limit short circuit current are difficult to apply online due to unable to completely evaluate its safety and feasibility. This paper presents an on-line decision support indicator system, which applied to evaluate online short circuit current level of power grid. Based on practical power grid model and typical cross-section, short circuit current level under the current and future maintenance mode is analyzed, decision support to limit short circuit current is given, and the effectiveness and feasibility of limiting measures are evaluated. Analysis results show that the index system is reasonable.

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Short circuit current forecast of large scale power grid based on improving BP Artificial Neural Network combined with Genetic Algorithm

2008 Third International Conference on Electric Utility Deregulation and Restructuring and Power Technologies ◽

10.1109/drpt.2008.4523583 ◽

2008 ◽

Cited By ~ 1

Author(s):

Bo Liu ◽

Yan Zhang

Keyword(s):

Neural Network ◽

Genetic Algorithm ◽

Artificial Neural Network ◽

Large Scale ◽

Short Circuit ◽

Power Grid ◽

Short Circuit Current ◽

Bp Artificial Neural Network ◽

Artificial Neural ◽

Grid Based

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Research of Large-Scale Offshore Wind Farm Collection System Short Circuit Equivalent Network

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.448-453.1732 ◽

2013 ◽

Vol 448-453 ◽

pp. 1732-1737

Author(s):

Liu Bin ◽

Hong Wei Cui ◽

Li Xu ◽

Kun Wang ◽

Zhu Zhan ◽

...

Keyword(s):

Large Scale ◽

Wind Farm ◽

Short Circuit ◽

Short Circuit Current ◽

System Optimization ◽

Offshore Wind ◽

Offshore Wind Farm ◽

Collection System ◽

Medium Voltage ◽

The Impact

This paper analyses the characteristics of large-scale offshore wind farm collection network and the impact of the medium voltage collection system optimization,while from the electrical technology point,it proposes the short circuit current of the collection network computational model and algorithms,based on the principle of equivalent circuit.Taking a wind power coolection system planned for a certain offshore wind farm planning for example, the validity of the model and algorithm is verified.

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Study on the Superconductor Current Limiter in Solving the Power Grid Short-Circuit Current

10.53469/ijpee.2021.03(06).01 ◽

2021 ◽

Vol 3 (6) ◽

Keyword(s):

Short Circuit ◽

Power Grid ◽

Short Circuit Current ◽

Current Limiter

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Analytical and Experimental Studies on Induced Current Switching by a Fault-Proof Gas Insulated Earthing Switch

International Journal of Emerging Electric Power Systems ◽

10.2202/1553-779x.2562 ◽

2010 ◽

Vol 11 (5) ◽

Author(s):

Mandava Mohana Rao ◽

Moutusi Paul ◽

H.S. Jain

Keyword(s):

Short Circuit ◽

Experimental Studies ◽

Short Circuit Current ◽

Design Parameters ◽

Induced Current ◽

Current Switching ◽

Test Circuit ◽

Reliable Performance ◽

Gas Insulated Substation ◽

The Impact

Fault-proof earthing switches are one of the important modules of a gas insulated substation, as it enables make at 100 percent short circuit current, which is functionally different from maintenance earthing switches. The fault-proof earthing switch shall be designed to make and break electro-magnetically and electro-statically induced currents as per IEC-62271-102. The paper discusses the impact of test circuit configurations and voltage on test parameters for gas insulated fault-proof earthing switch utilizing simulation with PSCAD software. Authors record the development of a 145 kV gas insulated fault proof earthing switch by considering novel design features like minimum arcing/pre-arcing time, effective current transfer from arcing contact to ground terminal, etc. The development has been evaluated successfully for electro-magnetically and electro-statically induced current duties as per IEC. Finally, design parameters to be considered for ensuring reliable performance during induced current switching from fault-proof earthing switches are also discussed.

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Effect of luminal acidity on the apical cation channel in rabbit esophageal epithelium

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00385.2005 ◽

2007 ◽

Vol 292 (3) ◽

pp. G796-G805 ◽

Cited By ~ 14

Author(s):

N. A. Tobey ◽

C. M. Argote ◽

M. S. Awayda ◽

X. C. Vanegas ◽

R. C. Orlando

Keyword(s):

Short Circuit ◽

Short Circuit Current ◽

Acid Reflux ◽

Cation Channel ◽

Esophageal Epithelium ◽

Protective Function ◽

Membrane Area ◽

Luminal Ph ◽

The Impact

Esophageal epithelial cells contain an apical cation channel that actively absorbs sodium ions (Na+). Since these channels are exposed in vivo to acid reflux, we sought the impact of high acidity on Na+channel function in Ussing-chambered rabbit epithelium. Serosal nystatin abolished short-circuit current ( Isc) and luminal pH titrated from pH 7.0 to pH ≥ 2.0 had no effect on Isc. Circuit analysis at pH 2.0 showed small, but significant, increases in apical and shunt resistances. At pH < 2.0, Iscincreased whereas resistance ( RT) decreased along with an increase in fluorescein flux. The change in Isc, but not RT, was reversible at pH 7.4. Reducing pH from 7.0 to 1.1 with H2SO4gave a similar pattern but higher Iscvalues, suggesting shunt permselectivity. A 10:1 Na+gradient after nystatin increased Iscby ∼4 μAmps/cm2and this declined at pH ≤ 3.5 until it reached ∼0.0 at pH 2.0. Impedance analysis on acid-exposed (non-nystatin treated) tissues showed compensatory changes in apical (increase) and basolateral (decrease) resistance at modest luminal acidity that were poorly reversible at pH 2.0 and associated with declines in capacitance, a reflection of lower apical membrane area. In esophageal epithelium apical cation channels transport Na+at gradients as low as 10:1 but do not transport H+at gradients of 100,000:1 (luminal pH 2.0). Luminal acid also inhibits Na+transport via the channels and abolishes it at pH 2.0. These effects on the channel may serve as a protective function for esophageal epithelium exposed to acid reflux.

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An investigation of the impact of technology scaling on power wasted as short-circuit current in low voltage static CMOS circuits

Proceedings of 1996 International Symposium on Low Power Electronics and Design ◽

10.1109/lpe.1996.547497 ◽

2002 ◽

Cited By ~ 19

Author(s):

A. Chatterjee ◽

M. Nandakumar ◽

Ih-Chin Chen

Keyword(s):

Low Voltage ◽

Short Circuit ◽

Short Circuit Current ◽

Cmos Circuits ◽

Technology Scaling ◽

Impact Of Technology ◽

The Impact

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The Impact of Synchronous Distributed Generation (DG) on Distribution System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.785.388 ◽

2015 ◽

Vol 785 ◽

pp. 388-392 ◽

Cited By ~ 1

Author(s):

Hasmaini Mohamad ◽

Shahrani Shahbudin ◽

Nofri Yenita Dahlan

Keyword(s):

Distributed Generation ◽

Distribution System ◽

System Performance ◽

Power Flow ◽

Short Circuit ◽

Short Circuit Current ◽

Voltage Profile ◽

Before And After ◽

Potential Benefits ◽

The Impact

Interconnection of Distributed Generation (DG) in distribution system presents many potential benefits as well as drawbacks. The impacts of DG might vary with the types of generator. This paper presents a study on the impacts of synchronous DG's interconnection in distribution system. Steady state analysis is carried out to analyze the impact of DG on voltage profile and short circuit current considering before and after DG interconnection. Dynamic analysis is also performed for investigating the performance of DG when a part of distribution system is being islanded. Results show that the penetration of DG contributes to the changes of power flow in the system, hence give impacts to the overall system performance.

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Fault Assessment and Mitigation of the 132kV Transmission Line in Nigeria using Improved Resonant Fault Current Limiting (RFCL) Protection Scheme

European Journal of Engineering Research and Science ◽

10.24018/ejers.2018.3.10.796 ◽

2018 ◽

Vol 3 (10) ◽

pp. 38-44

Author(s):

D. C. Idoniboyeobu ◽

S. L. Braide ◽

Wigwe Elsie Chioma

Keyword(s):

Power System ◽

Transmission Line ◽

Short Circuit ◽

Short Circuit Current ◽

Resonant Circuit ◽

Fault Current ◽

Protection Scheme ◽

Current Limiting ◽

Simulation Results ◽

The Impact

This research work proposed an improved Resonant Fault Current Limiting (RFCL) protection scheme to reduce the impact of three-phase short-circuit faults in a power system sub-transmission network. The model used an interpolator-extrapolator technique based on a Resonant Fault Current Limiter (RFCL) for automating the procedure of predicting the required reactor value that must be in resonant circuit to limit the short-circuit current values to permissible values. Using the developed model, short-circuit fault simulations on the three phases of the transmission line (Phase A-C) were performed in the MATLAB-SIMULINK environment. Simulation results were obtained by varying the resonant inductance (reactor) parameter of the RFCL circuit for each of the phases to obtain permissible short-circuit current levels and the values used to program a functional interpolator-extrapolator in MATLAB; the resonant values were typically set to values of inductance equal to 0.001H, 0.01H and from 0.1H to 0.5H in steps of 0.1H. Simulation results revealed the presence of very high short-circuit current levels at low values of the resonant inductor. From the results of simulations, there are indications that the RFCL approach is indeed very vital in the reduction of the short circuit current values during the fault and can safeguard the circuit breaker mechanism in the examined power system sub-transmission system. In addition, lower fault clearing times can be obtained at higher values of inductances; however, the clearance times start to converge at inductance values of 0.1H and above.

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A Unified Approach for Analysis of Faults in Different Configurations of PV Arrays and Its Impact on Power Grid

Energies ◽

10.3390/en13010156 ◽

2019 ◽

Vol 13 (1) ◽

pp. 156 ◽

Cited By ~ 5

Author(s):

Saba Gul ◽

Azhar Ul Haq ◽

Marium Jalal ◽

Almas Anjum ◽

Ihsan Ullah Khalil

Keyword(s):

Thin Film ◽

Short Circuit ◽

Power Grid ◽

Open Circuit ◽

Fault Analysis ◽

Operating Conditions ◽

Power Grids ◽

Pv System ◽

Multiple Faults ◽

The Impact

Fault analysis in photovoltaic (PV) arrays is considered important for improving the safety and efficiency of a PV system. Faults do not only reduce efficiency but are also detrimental to the life span of a system. Output can be greatly affected by PV technology, configuration, and other operating conditions. Thus, it is important to consider the impact of different PV configurations and materials for thorough analysis of faults. This paper presents a detailed investigation of faults including non-uniform shading, open circuit and short circuit in different PV interconnections including Series-Parallel (SP), Honey-Comb (HC) and Total-cross-Tied (TCT). A special case of multiple faults in PV array under non-uniform irradiance is also investigated to analyze their combined impact on considered different PV interconnections. In order to be more comprehensive, we have considered monocrystalline and thin-film PV to analyze faults and their impact on power grids. Simulations are conducted in MATLAB/Simulink, and the obtained results in terms of power(P)–voltage(V) curve are compared and discussed. It is found that utilization of thin-film PV technology with appropriated PV interconnections can minimize the impact of faults on a power grid with improved performance of the system.

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