Three Phase Induction Motor Working Principle

difference between dc motor and dc generator

The three-phase induction motor, like all electric motors, operates by means of interaction between magnetic fields. The stator magnetic field in a three-phase induction motor rotates around the air gap between the stator and the rotor. The direction of field rotation determines which way the motor turns and is controlled …

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Three Phase Induction Motor Construction

Exploded view of a three-phase induction motor

Like all motors, a three-phase induction motor contains a stator (the stationary part) and a rotor (which rotates). Each contains electrical windings that carry current and thus creates a magnetic field. The interaction of the magnetic fields creates the torque that rotates the rotor and the load. Figure 1 shows …

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Electronic Voltmeter Working and Block Diagram

Electronic Voltmeter

An analog electronic voltmeter uses an electronic amplifier to improve the performance of an electromechanical voltmeter. For example, an electronic voltmeter has a much higher input resistance than an electromechanical instrument, so voltmeter loading effect is considerably reduced. Also, voltage levels that are normally too small for measuring on an …

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Conductors and Insulators Definition and Examples

cable cross section

Conductors carry electric current. Insulators protect conductors and protect people from conductors. Whether a material is a conductor or an insulator depends on its atoms and on the relationship of each atom to its surrounding atoms. Insulators may break down if subjected to excessive voltages. Similarly, conductors may be destroyed …

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Three Phase Transformer Construction

2500 kVA power transformer.

A transformer consists of two or more electrical windings that are linked together by a magnetic field. Except for special-purpose transformers, the coupling is enhanced with a ferromagnetic core. Transformers are often drawn as shown in Figure 1, with the primary coil on one leg and the secondary coil on …

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Battery Sizing Calculation | Solved Example


This particular article talks about the battery sizing for certain applications such as Uninterrupted Power Supply (UPS), solar PV system, telecommunications, and other auxiliary services in power system. Whatsoever the practical application, batteries are proven technology to store an electrical energy. Other than storage purposes, batteries are extensively utilized in …

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Load Profile Calculation | Solved Example

The load profile is an approximation of the aggregate energy required from a power system over a particular time period (e.g., years, days, hours). The load profile is demonstrated in a two-dimension graph exhibiting the instantaneous load (in Volt-Amperes) over a certain period of time and presents an easy way …

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Solar PV System Sizing: Step By Step Guide

solar pv system sizing

This particular article talks about the standalone solar photovoltaic (PV) system sizing. Standalone PV systems are primarily utilized for providing power to small, remote areas where it’s impractical to lay down a transmission line or even have some alternative generation option like diesel generators. Though this article focuses mainly towards …

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Autotransformer: Working, Advantages, Disadvantages

Autotransformer Definition The autotransformer has a single winding on an iron core. One of the coil terminals is common to both input and output, and the other output terminal is movable so that it can make contact with any turn on the winding. Step-Up/ Step-Down Autotransformer An autotransformer can be …

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Three Phase Transformer Connections Phasor Diagrams

Wye-Wye Three-Phase Transformer Connection

Three Phase Transformer Connections A three-phase transformer is built for a specific connection and voltage transformation and the unit will have a nameplate with the internal connections shown. When a single unit or bank of three is used, there are four types of connections. The four basic connections are: Y-Y, Y-∆, ∆-Y, and ∆-∆. …

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Transformer Nameplate Details Explained

transformer nameplate

Transformer nameplates contain several standard items of information and other optional information. Transformer nameplate must specify the following parameters: Volt-Ampere (VA) or kilovolt-amperes (kVA) rating The voltage rating of both the primary and secondary circuits The impedance rating of the transformer (normally restricted to 25 kVA or larger) The required …

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Passive Components in AC Circuits with Equations

figure 11 parallel rlc circuit

There are three key passive elements used in many electrical and electronic circuits such as: Resistor, Inductor, and Capacitor. All these three elements limit the current flow but in a dissimilar manner. Since passive elements exhaust energy, they cannot amplify the electrical signals power employed to them and will always …

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Transformer Polarity Test

Transformer Polarity Markings

Transformer windings are marked to identify terminals with the same polarity. Polarity marks may either be dots or + marks. Alternatively, polarity marks may be shown by assigning the same subscripts to corresponding primary and secondary labels, H and X, respectively. Thus, when the primary terminals are named H1 and …

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Difference between Traditional Power Grid and Smart Grid

tradition grid vs smart grid

The traditional power grid is basically the interconnection of various power systems elements such as synchronous machines, power transformers, transmission lines, transmission substations, distribution lines, distribution substations, and different types of loads. They are located far from the power consumption area and electric power is transmitted through long transmission lines. …

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