## Causes of Low Power Factor

Low power factor has several disadvantages in power system. The main effect of low power factor is to increase the current and hence increase losses. This reduces overall system efficiency. Low power factor is thus not desirable from economic point of view. Let us first understand the basic cause for low power factor. We know … Read more

## Proximity Effect – Definition, Cause and Affecting Factors

Definition: Proximity Effect is the phenomena of non-uniform current distribution on the surface of adjacent current carrying conductor due to the effect of another current carrying conductor in its proximity. Since in cables, the conductors are very near to each other, this effect is dominant. Whereas in overhead lines as lines are far apart when … Read more

## Effect of Earth on Capacitance of Transmission Line

In Transmission Line, two types of capacitance exists: First one is capacitance between the phase conductors and the second one is shunt capacitance between the conductor and the earth. Capacitance between the phase conductors is not only dependent of conductor spacing, radius of conductor and height of conductor from the ground rather it is also … Read more

## Travelling Wave on Transmission Line

Travelling wave on transmission line is the voltage / current waves which propagate from the source end to the load end during the transient condition. These waves travel along the line with the velocity equal to velocity of light if line losses are neglected. But practically there always exists some line loss and hence these … Read more

## The Swing Equation – Definition and Derivation

What is Swing Equation? The Swing Equation of generator describes the relative motion between the rotor axis and the synchronously rotating stator filed axis with respect to time. This equation is very helpful in analyzing the stability of connected machines (machine here means generator). Derivation of Swing Equation: As we know that in a synchronous … Read more

## Why Cable Bonding Required?

Cable bonding is basically the method of making electrical connection between the sheaths of two cables. Such electrical connection of sheaths may either be done at one end or at both the ends of the cable depending upon the application. In this post we will discuss the importance of bonding of cable. As we know … Read more

## Cable Sheath Loss and Its Calculation

When single core cable is used for AC power transmission, the current flowing through the core of cable set up pulsating magnetic field in its surrounding. This magnetic field links with the cable sheath and hence as per the Faraday’s Law an induced voltage is developed in the sheath. This induced voltage in certain conditions … Read more

## Load Bus, Generator Bus and Slack Bus

Power System is nothing but the interconnection of various bus. Each of these buses are associated with four electrical parameters namely voltage with magnitude and phase angle, active power and reactive power. These fours parameters are not completely know but in practical situation only two are known and the remaining two parameters are calculated using … Read more

## Calculation of Restriking Voltage

Restriking voltage is the transient voltage appearing across the breaker contacts immediately after the opening of breaker contacts. It is also called Transient Recovery Voltage (TRV). Restriking voltage is associated with high frequency which die out quickly. Even though restriking voltage is lasts for very short duration, its importance for breaker fault clearing cannot be … Read more

## First Pole to Clear Factor- Calculation & Significance

First Pole to Clear Factor of a Circuit Breaker is the ratio of power frequency recovery voltage across the first pole to clear the arc to the normal phase to ground voltage when all the three poles of breaker are open. It is denoted as kpp. If Vcb be the recovery voltage across the first … Read more