An Automatic Voltage Regulator (AVR) is a crucial control device used in alternators (synchronous generators) to maintain a constant terminal voltage by automatically controlling the field excitation current. It ensures stable operation of power systems under varying load conditions. Mechanism of Voltage Control The Automatic Voltage Regulator (AVR) controls the terminal voltage of an alternator …
An alternator is an electrical machine that converts mechanical energy into alternating electrical energy (AC). Principle of Operation Based on electromagnetic induction: Whenever a conductor cuts magnetic flux, an EMF is induced in it. Rotor produces rotating magnetic field Stator conductors remain stationary EMF is induced in stator windings Construction 1. Stator Laminated core Three-phase …
Pole Amplitude Modulation (PAM) is a method used to control the speed of a three-phase induction motor by changing the effective number of poles. It is a versatile technique used to control the speed of a three-phase squirrel-cage induction motor by effectively altering the number of active stator poles. Speed Equation \[ N_s = \frac{120f}{P} \] …
Pole Amplitude Modulation (PAM) of Three-Phase Induction Motor Read More »
A bus (or busbar) is a node in a power system where generators, loads, and transmission lines are interconnected. For load flow analysis, buses are classified based on known and unknown electrical quantities. Basic Quantities Each bus is associated with four quantities: Voltage Magnitude (\(|V|\)) Voltage Angle (\(\delta\)) Real Power (\(P\)) Reactive Power (\(Q\)) Only …
In an electric power system, the distribution system is responsible for delivering electrical energy from substations to end consumers. Among the various types of distribution systems, the radial distribution system is the simplest and most widely used configuration, especially in rural and semi-urban areas. Introduction A radial distribution system is one in which each consumer …
In electrical engineering, the selection of conductor materials for electric wires and transmission lines depends not only on electrical properties but also on mechanical strength. One important mechanical property is the Ultimate Tensile Strength (UTS) of the conductor material. Copper and aluminium are the two most commonly used materials in electrical conductors. Their ultimate tensile …
Ultimate Tensile Strength of Copper and Aluminium Read More »
In electrical engineering, conducting materials such as copper and aluminium are widely used for manufacturing electric wires and cables. One of the important physical properties considered while selecting these materials is specific gravity. Specific gravity affects the weight, mechanical strength, and cost of electrical conductors, which are important factors in the design of power transmission …
In modern high-voltage and extra-high-voltage (EHV) transmission systems, the use of bundled conductors is common. Bundled conductors help reduce corona losses, radio interference, and surge impedance, thereby improving the power transfer capability of the transmission line. One important conductor arrangement used in EHV transmission is the Quad Bersimis conductor configuration. This configuration is particularly useful …
In power transmission systems, the concept of Surge Impedance Loading (SIL) plays an important role in understanding the power transfer capability of transmission lines. It is particularly important in the analysis and design of high-voltage transmission systems used in long-distance power transmission. SIL helps engineers determine the loading condition of a transmission line at which …
Surge Impedance Loading (SIL) of AC Transmission Lines Read More »
Large power generators used in thermal and hydroelectric power plants produce a huge amount of heat during operation. Efficient cooling is therefore essential to maintain the temperature of the stator and rotor windings within safe limits. One of the most effective cooling methods used in large turbo-alternators is hydrogen cooling. Hydrogen gas is used as …