Table of Contents
What is GMR of a conductor?
Geometrical Mean Radius GMR is basically the Geometric Mean of distances between the strands of a conductor. It is the fictitious radius of a conductor having no internal flux linkage but only external flux linkage.
Is the GMR less in bundled conductors?
Bundled conductor are those conductors which form from two or more stranded conductors, bundled together to get more current carrying capacity. By using bundle conductors instead of the single conductor in the transmission line increases the GMR of the conductors.
What is the bundling of the conductor?
What is Bundled Conductor? We call bundled conductor to those conductors which form from two or more stranded conductors, bundled together to get more current carrying capacity. Here, we use two or more stranded conductors per phase.
What is the efficiency of transmission line?
An ideal transmission line has 100\% efficiency (i.e. zero losses) which is not possible practically.
What is difference between GMD and GMR?
GMD stands for Geometrical Mean Distance. It is the equivalent distance between conductors. GMD comes into picture when there are two or more conductors per phase used as in bundled conductors. GMR stands for Geometric mean Radius.
What is skin effect in electrical engineering?
skin effect, in electricity, the tendency of alternating high-frequency currents to crowd toward the surface of a conducting material. This phenomenon restricts the current to a small part of the total cross-sectional area and so has the effect of increasing the resistance of the conductor.
How does a bundled conductor reduce corona?
Bundled conductors per phase reduces the voltage gradient in the vicinity of the line. Thus reduces the possibility of the corona discharge. (Corona effect will be observed when the air medium present between the phases charged up and start to ionize and acts as a conducting medium.
What is the GMR of conductor in a bundle?
The conductors of a bundle are separated at regular intervals with spacer dampers that prevent clashing of the conductors and prevent them from swaying in the wind. They also connect the conductors in parallel. where Ds is the GMR of conductor. The GMR for three-conductor and four-conductor bundles are given respectively by
What are the advantages of making a bundle conductor?
It also reduces voltage gradient, corona loss, radio interference, surge impedance of the transmission lines. By making bundle conductor, the geometric mean radius (GMR) of the conductor increased. As the self GMR of the conductor increases, the inductance of the conductor decreases.
What happens to inductance when a conductor is bundled?
Bundling of conductors leads to a reduction in line inductance. We know that inductance of a line is given by, By making bundled conductor, the geometric mean radius (GMR) of the conductor increased. As the self GMR of the conductor increases, the inductance of the conductor decreases.
What is the difference between GMD and GMR in transmission lines?
In GMD we take the Geometrical Mean of distances between the strands of two Transmission Lines while in GMR, Geometrical Mean of distances between the stands of a single composite conductor are calculated. Let us assume two composite conductors used in Transmission Line as shown in figure below.