Ferranti effect is due to voltage drop across the line inductance, due to charging current, being in phase with the applied voltage at the sending end of the line. Thus both capacitance and inductance are necessary to cause this phenomenon. The capacitance, and therefore, charging current is negligible in short lines but significant in medium and long transmission lines. On [...]
In this article we will discuss about the capacitance of overhead transmission lines. We know that any two conductors separated by an insulating medium constitute a condenser or a capacitor. In case of an overhead line two conductors form the two plates of a capacitor and the air between the conductors behaves as the dielectric medium. Thus an overhead line [...]
In this article we will discuss about:- 1. Introduction to Long Transmission Lines 2. Analysis of Long Transmission Lines (Rigorous Method of Solution of Long Transmission Lines) 3. Surge Impedance 4. Long Transmission Line with Series Impedance 5. Network of a Long Transmission Line 6. Constant Voltage Transmission in Long Transmission Lines and Other Details. Contents: Introduction to Long Transmission [...]
In this article we will discuss about:- 1. Introduction to Corona 2. Factors Affecting Corona 3. Causes 4. Corona Power Loss 5. Methods of Reducing Corona Effects 6. Advantages and Disadvantages. Contents: Introduction to Corona Factors Affecting Corona Causes of Corona Corona Power Loss Methods of Reducing Corona Effects Advantages and Disadvantages of Corona 1. Introduction to Corona: When an [...]
The inductance and capacitance of each phase will be different in case of conductors of three phase line being spaced irregularly. The apparent resistance of the conductors is also affected on account of transfer of power between the phases, which occur due to mutual inductance. Thus all the three line constants are affected by irregular spacing of the conductors in [...]
In this article we will discuss about:- 1. Introduction to Transmission Lines 2. Conductor Configurations, Spacing’s and Clearances of Transmission Lines 3. Span Lengths 4. Sag and Tension 5. Stringing Chart 6. Sag Template 7. Equivalent Span 8. Vibrations and Dampers. Contents: Introduction to Transmission Lines Conductor Configurations, Spacing’s and Clearances of Transmission Lines Span Lengths of Transmission Lines Sag [...]
In determination of capacitance of transmission lines, the presence of earth is ignored. But it is not true; the presence of earth affects the electric field of a line and so the capacitance. The effect of earth on capacitance can be modelled by the method of images. The electric field of too long, parallel conductors having charge +q and -q [...]