Analysis of voltage and short-circuit current on photovoltaic generation dominated distribution systems

In this paper, a new concept of short-circuit current (SCC) reduction for power distribution systems is presented and analyzed. Conventional fault current limiters (FCLs) are connected in series with a circuit breaker (CB) that is required to limit the short-circuit current. Instead, the proposed scheme consisted of the parallel connection of a current-controlled power converter to the same bus intended to reduce the amplitude of the short-circuit current. This power converter was controlled to absorb a percentage of the short-circuit current from the bus to reduce the amplitude of the short-circuit current. The proposed active short-circuit current reduction scheme was implemented with a cascaded H-bridge power converter and tested by simulation in a 13.2 kV industrial power distribution system for three-phase faults, showing the effectiveness of the short-circuit current attenuation in reducing the maximum current requirement in all circuit breakers connected to the same bus. The paper also presents the design characteristics of the power converter and its associated control scheme.

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Photovoltaic Generation of Electricity Using Near-Field Radiation

ASME/JSME 2011 8th Thermal Engineering Joint Conference ◽

10.1115/ajtec2011-44513 ◽

2011 ◽

Cited By ~ 3

Author(s):

Katsunori Hanamura ◽

Hirofumi Fukai ◽

Elaiyaraju Srinivasan ◽

Masao Asano ◽

Teppei Masuhara

Keyword(s):

Evanescent Wave ◽

Short Circuit ◽

Near Field ◽

Short Circuit Current ◽

Photovoltaic Cell ◽

Short Circuit Current Density ◽

Wave Radiation ◽

Wave Effect ◽

Photovoltaic Generation ◽

Field Radiation

Near-field radiation that has a high intensity of electric field was applied to enhance conversion from thermal energy to electricity in a wavelength range less than 1.1 μm or 1.8 μm. A commercial Si-photovoltaic cell and a thermophotovoltaic cell made of GaSb semiconductors were used to confirm that the near-field radiation effect (the evanescent wave effect) can be applied to enhance generation of electricity. As a result, an increase in output power generation of electricity by the evanescent wave effect was detected and the short-circuit current density increased about 1.3 times for the Si-PV cell and 3.0 times for the GaSb-TPV cell as larger than those obtained by the conventional propagating-wave radiation.

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AC Microgrid Protection System Design Challenges—A Practical Experience

Energies ◽

10.3390/en14072016 ◽

2021 ◽

Vol 14 (7) ◽

pp. 2016

Author(s):

Sarat Chandra Vegunta ◽

Michael J. Higginson ◽

Yashar E. Kenarangui ◽

George Tsai Li ◽

David W. Zabel ◽

...

Keyword(s):

System Design ◽

Distribution Systems ◽

Failure Modes ◽

Short Circuit ◽

Short Circuit Current ◽

Practical Experience ◽

Protection System ◽

Implementation Challenges ◽

Design Speed ◽

Design Challenges

Alternating current (AC) microgrids are the next step in the evolution of the electricity distribution systems. They can operate in a grid-tied or island mode. Depending on the services they are designed to offer, their grid-tied or island modes could have several sub-operational states and or topological configurations. Short-circuit current levels and protection requirements between different microgrid modes and configurations can vary significantly. Designing a microgrid’s protection system, therefore, requires a thorough understanding of all microgrid operational modes, configurations, transitional states, and how transitions between those modes are managed. As part of the microgrid protection design, speed and reliability of information flow between the microprocessor-based relays and the microgrid controller, including during microgrid failure modes, must be considered. Furthermore, utility protection practices and customer requirements are not always inclusive of the protection schemes that are unique to microgrids. These and other aspects contribute to the overall complexity and challenge of designing effective microgrid protection systems. Following a review of microgrid protection system design challenges, this paper discusses a few real-world experiences, based on the authors’ own engineering, design, and field experience, in using several approaches to address microgrid protection system design, engineering, and implementation challenges.

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A Novel Machine Learning-Based Short-Circuit Current Prediction Method for Active Distribution Networks

Energies ◽

10.3390/en12193793 ◽

2019 ◽

Vol 12 (19) ◽

pp. 3793 ◽

Cited By ~ 1

Author(s):

Zheng ◽

Wang ◽

Jiang ◽

He

Keyword(s):

Distribution Systems ◽

Large Scale ◽

Short Circuit ◽

Distribution Network ◽

Prediction Method ◽

Short Circuit Current ◽

Distribution Networks ◽

Test System ◽

High Penetration ◽

Active Distribution Networks

The traditional mechanism models used in short-circuit current calculations have shortcomings in terms of accuracy and speed for distribution systems with inverter-interfaced distributed generators (IIDGs). Faced with this issue, this paper proposes a novel data-driven short-circuit current prediction method for active distribution systems. This method can be used to accurately predict the short-circuit current flowing through a specified measurement point when a fault occurs at any position in the distribution network. By analyzing the features related to the short-circuit current in active distribution networks, feature combination is introduced to reflect the short-circuit current. Specifically, the short-circuit current where IIDGs are not connected into the system is treated as the key feature. The accuracy and efficiency of the proposed method are verified using the IEEE 34-node test system. The requirement of the sample sizes for distribution systems of different scale is further analyzed by using the additional IEEE 13-node and 69-node test systems. The applicability of the proposed method in large-scale distribution network with high penetration of IIDGs is verified as well.

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