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 transformers are used quite extensively in power systems to transform a balanced set of three-phase voltages at a particular voltage level into a balanced set of voltages at another level. Transformers used between generators and transmission system, between transmission and sub-transmission system, and between sub-transmission and distribution systems are …

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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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RLC Series Circuit Problems with Solutions

RLC Electrical Network

These questions are related to RL Series Circuit, RC Series Circuit, and RLC Series Circuit. These topics are covered in detail here: RL Series Circuit RC Series Circuit RLC Series Circuit Impedance in an AC Circuit 1. Define a series RL circuit: The combination of a resistor and inductor connected …

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Lead Acid Battery: Construction, Working, Charging

Lead Acid Battery

Lead-Acid Battery Construction The lead-acid battery is the most commonly used type of storage battery and is well-known for its application in automobiles. The battery is made up of several cells, each of which consists of lead plates immersed in an electrolyte of dilute sulfuric acid. The voltage per cell …

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Transformer Losses and Efficiency Calculation

Complete Equivalent Circuit

Transformer Efficiency Definition The efficiency of the transformer is defined as the ratio of the power output Poutput and power input Pinput, both expressed in watts. Thus, \[\begin{matrix}   \eta =\frac{{{P}_{out}}}{{{P}_{in}}} & {} & \left( 1 \right)  \\\end{matrix}\] Or since the input is the output plus losses, \[\begin{matrix}   \begin{align}  & \eta …

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