Subject and UNIT: Transmission and Distribution: Unit III: (b) Insulators
Consider a string of suspension insulators. The number of porcelain discs are connected in series with the help of metal links.
Pin T- Suspension - Strain - Shackle - Stay
Subject and UNIT: Transmission and Distribution: Unit III: (b) Insulators
The use of proper insulator is an important part of the mechanical design of the overload lines. The various types of the insulators are, 1. Pin type insulators 2. Suspension type insulators 3. Strain insulators 4. Shackle insulators 5. Stay insulators
Porcelain - Glass - Synthetic Resin
Subject and UNIT: Transmission and Distribution: Unit III: (b) Insulators
The commonly used insulating materials, satisfying the above mentioned properties are, 1. Porcelain 2. Glass 3. Synthetic resin
Transmission and Distribution
Subject and UNIT: Transmission and Distribution: Unit III: (b) Insulators
Transmission and Distribution: Unit III: (b) Insulators : Syllabus, Contents
Transmission and Distribution
Subject and UNIT: Transmission and Distribution: Unit III: (b) Insulators
Transmission and Distribution: Unit III: (b) Insulators : Syllabus, Contents
Transmission and Distribution | Mechanical Design of Transmission Lines
Subject and UNIT: Transmission and Distribution: Unit III: (a) Mechanical Design of Transmission Lines
Transmission and Distribution: Unit III: (a) Mechanical Design of Transmission Lines : Two Marks Questions with Answers
Wooden - Reinforced concrete - Steel tubular poles - Latticed steel towers
Subject and UNIT: Transmission and Distribution: Unit III: (a) Mechanical Design of Transmission Lines
The structures which are used to support the transmission lines are called towers or line supports. The performance of transmission line depends also on the design of the towers.
Aeoline Vibrations - Galloping of Conductors - Stock-Bridge Type Vibration Damper - Factors Affecting Conductor Vibrations
Subject and UNIT: Transmission and Distribution: Unit III: (a) Mechanical Design of Transmission Lines
The conductors are supported on the string insulators at each tower. Under widely varying atmospheric conditions like strong wind velocities, the conductor can start vibrating mechanically in the vertical plane.
Subject and UNIT: Transmission and Distribution: Unit III: (a) Mechanical Design of Transmission Lines
instead of solving the cubic equation, it is possible to obtain the graph of tension in kg against temperature in °C and the graph of sag in metres against temperature in °C. Such graph is called stringing chart.
Subject and UNIT: Transmission and Distribution: Unit III: (a) Mechanical Design of Transmission Lines
Generally two types of towers are used to support the overhead transmission lines which are, 1. The standard or straight run or intermediate tower. 2. The angle or anchor or tension tower.
Mechanical Design of Transmission Lines
Subject and UNIT: Transmission and Distribution: Unit III: (a) Mechanical Design of Transmission Lines
We have seen that there is major difference between the calculation of sag and tension in still air and the calculation of sag and tension under severe atmospheric conditions like ice coating, wind pressure etc.
Calculation of Tension T and Conductor Half Span Length
Subject and UNIT: Transmission and Distribution: Unit III: (a) Mechanical Design of Transmission Lines
For earlier derivations we have assumed that the sag is small compared to the span and hence conductor takes the form of parabola.