Transmission expansion planning (TEP) is crucial for maintaining the reliable and efficient operation of the power systems, particularly in the face of increasing electricity demand and the integration of renewable energy sources. This paper aims to investigate the application of unconventional high surge impedance loading (HSIL) lines in TEP and presents a comparative analysis of their outcomes against conventional line-based TEP approaches. Starting with a 17-bus 500 kV test system, which can operate well under normal operating condition as well as all single contingency conditions, the objective is to connect a new load located in a new bus, bus #18, to the existing test system via two approaches: using conventional lines and incorporating unconventional HSIL lines. By comparing the number of lines required for the conventional and unconventional approaches, maintaining identical conductor weight per circuit, the effectiveness of unconventional HSIL lines in TEP is evaluated where using only two unconventional HSIL lines is sufficient to connect 1250 MW load demand at bus 18 while three transmission lines are required when using the conventional line. Finally, a thorough economic analysis has been conducted on both TEP scenarios, revealing that implementing unconventional HSIL lines leads to remarkable cost savings and thus can be considered a promising option for TEP studies.
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Smart Transmission Expansion Planning Based on the System Requirements: A Comparative Study with Unconventional Lines
This paper introduces a new concept in transmission expansion planning based on unconventional lines, termed “smart transmission expansion planning”. Traditionally, the domains of transmission expansion planning (TEP) and transmission line design are separate entities. TEP planners typically rely on the electrical specifications of a limited set of standard conventional line designs to evaluate planning scenarios, ultimately leading to the construction of the selected candidate line. In this context, it is noted that cost-effective scenarios often diverge from meeting the technical criteria of load flow analysis. To address this discrepancy, this paper proposes an alternative approach wherein TEP is conducted based on the specific requirements of the system earmarked for expansion. The transmission expansion planner initiates the process by determining optimal line parameter values that not only meet the operational criteria but also ensure cost-effectiveness. Subsequently, a line is designed to embody these optimal parameters. A detailed comparative analysis is conducted in this study, comparing the outcomes of TEP analyses conducted with conventional lines, unconventional lines, and lines featuring optimal parameters. Through extensive load flow analysis performed under normal and all single-contingency scenarios across three distinct loading conditions (peak load, dominant load representing 60% of peak load, and light load representing 40% of peak load), the results reveal that transmission lines engineered with optimal parameters demonstrate effective operation, with fewer transmission lines required to meet identical demands compared to other approaches.
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- Award ID(s):
- 2306098
- PAR ID:
- 10524672
- Publisher / Repository:
- Energies
- Date Published:
- Journal Name:
- Energies
- Volume:
- 17
- Issue:
- 8
- ISSN:
- 1996-1073
- Page Range / eLocation ID:
- 1912
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Transmission expansion planning (TEP) plays a vital role in ensuring the reliable and efficient operation of power systems, especially with the growing demand for electricity and the integration of renewable energy sources. This paper focuses on applying unconventional high surge impedance loading (HSIL) lines in transmission expansion planning and compares their outcomes with conventional line-based transmission expansion planning. Starting with a 17 bus- 500 kV power system connected by a conventional transmission line, the objective is to connect a new load located in a new bus, bus #18, to the existing 17-bus power system via two approaches: using conventional lines and incorporating unconventional HSIL lines. By comparing the number of lines required for the conventional and unconventional approaches, maintaining almost identical conductor volume per circuit, the effectiveness of unconventional HSIL lines in TEP is evaluated where using only two unconventional HSIL lines is sufficient to connect 1000 MW load demand at bus 18 while three lines are required when using the conventional design.more » « less
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