Details

Основной целью данной работы является анализ различных явлений при переключении вакуумных выключателей в распределительной цепи 11 кВ, которая подключена к высоковольтной передающей цепи 220 кВ через силовой трансформатор. Поэтому кривые намагничивания A-Wb силовых и трансформаторов напряжения с различными линейными емкостями были проанализированы с помощью моделирования EMTP-RV. Феррорезонанс наблюдался в трансформаторах напряжения и при коммутации фаз, и его можно было демпфировать с помощью сопротивления и шунтирующих реакторов.

The main objective of this work is to analyse different phenomena when switching vacuum circuit breakers on a 11kV distribution circuit, which is connected to a 220kV high-voltage transmission circuit through a power transformer. Therefore, the magnetisation curves A-Wb of power and voltage transformers with different line capacitances have been analysed by EMTP-RV simulation. The ferroresonace was observed in voltage transformers and when commutating phases and it was possible to damping it by the using of resistance and shunt reactors.

• INTRODUCTION
• 1.LITERATURE REVIEW
  • 1.1. Electrical Power Grids
  • 1.2. Types of Electrical Grids
  • 1.3. Power Grid Quality Problems
    • 1.3.1. External Overvoltage
    • 1.3.2. Internal Overvoltage
  • 1.4. Power Transformers
  • 1.5. Circuit Breakers
    • 1.5.1. Vaccum Circuit breaker
  • 1.6. Ferroresonace in Power Systems
• 2. DESCRIPTION OF COMPONENTS, PARAMETERS AND WORK
  • 2.1. Work Description and Tasks
  • 2.2. Distribution Metal Tower and Cable Selection
    • 2.2.1. OHL Cable Electrical and Mechanical Calcula
      • 2.2.1.1. Sag and Length calculation by catenary me
      • 2.2.1.2. Total Tension created by Cable in Tower h
    • 2.2.2. Tower Selection and characteristics
  • 2.3. High Voltage Power Transformer 220/11kV
    • 2.3.1. Calculation of Electrical Parameters for 22
    • 2.3.2. YnD Power transformer magnetization curve
  • 2.4. Distribution Transformer DnY 11/0.4kV
    • 2.4.1. Calculation of Electrical parameters DnY Di
    • 2.4.2. DnY Magnetization Curve
  • 2.5. Surge Arrester Electrical parameters calculat
• 3. DESIGN AND PARAMETERS OF MAIN CIRCUITS IN EMTP-
• 4. STUDY OF FERRORESONANT OVERVOLTAGES IN 11 KV NE
  • 4.1. Study of ferroresonant overvoltages in 11 kV
  • 4.2. Study of ferroresonant overvoltages in 11 kV
  • 4.3. Analyses of results obtained with one and two
• 5. FERRORESONANCE PROCESSES IN INCOMPLETE-PHASE SW
  • 5.1. Calculations of ferroresonance processes unde
• 6. DAMPING OF FERRORESONACE EFFECT IN 11KV LINE BY
  • 6.1. Damping of FRE by using Shunt Reactor
  • 6.2. Damping by introduction of series resistance
• 7. CONCLUSION
• REFERENCES