JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD

Prerequisite

Power Systems –I and Electromagnetic field theory

Course Objectives:

• To compute inductance and capacitance of different transmission lines.
• To understand performance of short, medium and long transmission lines.
• To examine the traveling wave performance and sag of transmission lines.
• To design insulators for over head lines and understand cables for power transmission.

Course Outcomes

After completion of this course, the student

• Able to compute inductance and capacitance for different configurations of transmission lines.
• Able to analyze the performance of transmission lines
• Can understand transient’s phenomenon of transmission lines.
• Able to calculate sag and tension calculations.
• Will be able to understand overhead line insulators and underground cables.

UNIT - I

Transmission Line Parameters: Types of conductors - calculation of resistance for solid conductors - Calculation of inductance for single phase and three phase, single and double circuit lines, concept of GMR & GMD, symmetrical and asymmetrical conductor configuration with and without transposition, Numerical Problems. Calculation of capacitance for 2 wire and 3 wire systems, effect of ground on capacitance, capacitance calculations for symmetrical and asymmetrical single and three phase, single and double circuit lines, Numerical Problems.

UNIT - II

Performance of Short and Medium Length Transmission Lines: Classification of Transmission Lines - Short, medium and long line and their model representations - Nominal-T, Nominal-Pie and A, B, C, D Constants for symmetrical & Asymmetrical Networks, Numerical Problems. Mathematical Solutions to estimate regulation and efficiency of all types of lines - Numerical Problems. Performance of Long Transmission Lines: Long Transmission Line - Rigorous Solution, evaluation of A,B,C,D Constants, Interpretation of the Long Line Equations, Incident, Reflected and Refracted Waves -Surge Impedance and SIL of Long Lines, Wave Length and Velocity of Propagation of Waves - Representation of Long Lines - Equivalent-T and Equivalent Pie network models (numerical problems).

R16 B.TECH EEE.

UNIT - III

Power System Transients: Types of System Transients - Travelling or Propagation of Surges - Attenuation, Distortion, Reflection and Refraction Coefficients - Termination of lines with different types of conditions - Open Circuited Line, Short Circuited Line, T- Junction, Lumped Reactive Junctions (Numerical Problems), Bewley’s Lattice Diagrams (for all the cases mentioned with numerical examples). Various Factors Governing The Performance of Transmission Line: Skin and Proximity effects - Description and effect on Resistance of Solid Conductors - Ferranti effect - Charging Current - Effect on Regulation of the Transmission Line. Corona - Description of the phenomenon, factors affecting corona, critical voltages and power loss, Radio Interference.

UNIT - IV

Overhead Line Insulators: Types of Insulators, String efficiency and Methods for improvement, Numerical Problems - voltage distribution, calculation of string efficiency, Capacitance grading and Static Shielding. Sag and Tension Calculations: Sag and Tension Calculations with equal and unequal heights of towers, Effect of Wind and Ice on weight of Conductor, Numerical Problems - Stringing chart and sag template and its applications.

UNIT - V

Underground Cables: Types of Cables, Construction, Types of Insulating materials, Calculation of Insulation resistance and stress in insulation, Numerical Problems. Capacitance of Single and 3-Core belted cables, Numerical Problems. Grading of Cables - Capacitance grading - Numerical Problems, Description of Inter-sheath grading - HV cables.

TEXT BOOKS:

• 1. “C. L. Wadhwa”, “Electrical power systems”, New Age International (P) Limited Publishers, 1998.
• 2. “Grainger and Stevenson”, “Power Systems Analysis”, Mc Graw Hill, 1 st Edition 2003.
• 3. “M. L. Soni, P. V. Gupta, U.S. Bhatnagar and A. Chakrabarthy”, Power System Engineering, Dhanpat Rai & Co Pvt. Ltd, 2009.

REFERENCE BOOKS:

• 1. “I. J. Nagarath & D. P Kothari” , “Power System Engineering”, TMH, 2nd Edition 2010
• 2. “B. R. Gupta”, “Power System Analysis and Design”, Wheeler Publishing, 1998.
• 3. “Abhijit Chakrabarti and Sunitha Halder”, “Power System Analysis Operation and control”, PHI, 3 rd Edition, 2010 R16 B.TECH EEE.