Gas-insulated lines for HVAC transmission for long distance bulk-power transmission (HVAC)

Thèse de Bachelor , 2018 , 89 Pages , Note: 76

Ingénierie - Technique énergétique

Various converters, generators, and other high power facilities are situated several kilometres away from metropolitan areas. Thus, numerous renewable energy sources with an interconnection between the generation and transmission technology require an efficient and high capacity system which entails the implementation of gas-insulated lines.

Gas-insulated lines (GIL) are a resourceful High Voltage (HV) transmission technology, which offers an alternative to traditional cables or overhead lines (OHL). Conventional cables are unable to provide adequate long-distance bulk power transmission as the ratings for voltage or useful power at the load aren’t sufficient in proportion to the line length. OHL with a lattice tower is a typical transmission method on shore with submarine Cross-linked Polyethylene (XLPE) cables or GIL utilised underground in challenging areas due to their flexibility and functional characteristics.

A 420/550 kV GIL representation comprising of a multiphase model and constant RLC values presents an adequate analysis of the system. Fundamentally, GIL offers encouraging results given the high-pressured insulation medium, skin effect and returning current. Furthermore, by utilising a common platform for the simulations, a fair comparison with various HV transmission alternatives is accomplished. Additionally, this investigation incorporates an overview of the overvoltage and recovery characteristics of the simulated GIL with an adequate power supply concerning the installation of a synchronous generator and wind turbine.

This research examines the economic factors with a distinctive focus on substantial investments made into offshore wind farms and GIL functioning in High Voltage Alternating Current (HVAC). The cost for this particular technical solution may provide an alternative to High Voltage Direct Current (HVDC) networks with Voltage Source Converters (HVDC-VSC) and submarine XLPE cables. The price per generating hour accumulates over time which reflects the total costs. Ultimately, the cost per unit is related to the demand.

Finally, the literature review includes technical data, background information and a verification process for the simulation results.

Inhaltsverzeichnis (Table of Contents)

• 1. Introduction
  • 1.1. Renewable energy: Integration with GIL
  • 1.2. Power transmission techniques: Roles and problems
    • 1.2.1. Conventional transmission systems
    • 1.2.2. GIL applications
  • 1.3. Project goals and incentives
    • 1.3.1. Aims and objectives
    • 1.3.2. Project incentives
• 2. Literature review
  • 2.1. Advantages of GIL
    • 2.1.1. High-reliability standards
    • 2.1.2. Low transmission losses
    • 2.1.3. Low magnetic field ratings: GIL review
    • 2.1.4. No ageing
  • 2.2. Technical data and design of coaxial GIL: Background research
    • 2.2.1. Case study: Second generation GIL at Palexpo exhibition hall
    • 2.2.2. Design of a 420/550 kV GIL
• 3. Transmission characteristics of GIL
  • 3.1. GIL: PSCAD model and simulations
    • 3.1.1. EMTDCS/PSCAD: GIL simulation model
    • 3.1.2. Simulation results: 0.7 and 0.8 power factor operation
    • 3.1.3. 300km GIL results
    • 3.1.4. Verification of the results
    • 3.1.5. Loading conditions effect on GIL
    • 3.1.6. Leading power factor effect on the GIL: PSCAD limitation
    • 3.1.7. Lagging power factor effect on the GIL
• 4. Transmission technologies
  • 4.1. Transmission characteristics of OHL
    • 4.1.1. OHL: Design and implementation
  • 4.2. Underground XLPE cables analysis
    • 4.2.1. Comparison of transmission technologies
  • 4.3. Wind turbine analysis and energisation: Overvoltage and transient recovery voltage (TRV) of GIL integrated with OHL
    • 4.3.1. Design and specifications of GIL with a renewable wind source
  • 4.4. HVDC technology: HVDC systems and economic analysis
    • 4.4.1. Alternative voltage control strategy
    • 4.4.2. Financial expenditures and Return on Investment (ROI) of transmission technologies

Zielsetzung und Themenschwerpunkte (Objectives and Key Themes)

This report examines the potential of gas-insulated lines (GIL) for long-distance bulk-power transmission in High Voltage Alternating Current (HVAC) systems. The research explores the advantages of GIL in terms of reliability, transmission losses, and environmental impact, comparing them to conventional overhead lines (OHL) and underground XLPE cables. The report also analyzes the integration of GIL with renewable energy sources, particularly wind turbines, and investigates the economic feasibility of GIL in comparison to HVDC systems.

• Advantages of GIL for long-distance bulk-power transmission
• Comparison of GIL with conventional transmission technologies
• Integration of GIL with renewable energy sources, particularly wind turbines
• Economic analysis of GIL in comparison to HVDC systems
• Overvoltage and transient recovery characteristics of GIL systems

Zusammenfassung der Kapitel (Chapter Summaries)

• Chapter 1: Introduction introduces the concept of GIL as a potential solution for efficient long-distance bulk-power transmission. It discusses the role of renewable energy integration, outlining the challenges and opportunities associated with various power transmission technologies. This chapter establishes the project goals, objectives, and incentives driving this research.
• Chapter 2: Literature Review delves into the advantages of GIL, highlighting their high reliability standards, low transmission losses, and minimal magnetic field impact. This chapter also explores the design of coaxial GIL, utilizing case studies and technical data to provide a foundation for further analysis.
• Chapter 3: Transmission Characteristics of GIL focuses on the simulation of GIL performance using PSCAD software. It presents the results of simulations for different operating conditions and power factors, analyzing the impact of load conditions on GIL performance. This chapter also addresses verification of the simulation results.
• Chapter 4: Transmission Technologies examines the characteristics of OHL and underground XLPE cables, comparing their performance with GIL. This chapter explores the integration of wind turbines with GIL, analyzing overvoltage and transient recovery characteristics. It also investigates the economic viability of GIL in comparison to HVDC systems.

Schlüsselwörter (Keywords)

The research focuses on the evaluation of gas-insulated lines (GIL) for long-distance bulk-power transmission in High Voltage Alternating Current (HVAC) systems. Key themes include high-reliability standards, low transmission losses, minimal magnetic field impact, integration with renewable energy sources, economic analysis, and comparison with conventional transmission technologies such as overhead lines (OHL) and underground XLPE cables. The research utilizes simulations using PSCAD software, analyzing overvoltage and transient recovery characteristics. The economic analysis considers the return on investment (ROI) of GIL compared to HVDC systems.

• Université: University of Manchester
• Cours: Electrical and electronic engineering
• Note: 76
• Auteur: Llion Stephen (Auteur)
• Année de publication: 2018
• Pages: 89
• N° de catalogue: V437194
• ISBN (ebook): 9783668775046
• ISBN (Livre): 9783668775053
• Langue: anglais
• Sécurité des produits: GRIN Publishing GmbH