Substation

Percentage Reactance in Power System (Transformer, Generator or Reactor)
Percentage reactance of power system elements such as generator, transformer and reactor are extensively used in short circuit calculation when any fault occurs in the system. Most faults in the

Load Duration Curve in Power Station
Load duration curves are used in power stations to illustrate the relationship between generating capacity requirements and capacity utilization. A load duration curve (LDC) is similar to a load curve

Disconnect Switches (Isolator) in Substation: Types, Design and Working
A disconnect switch is a mechanical device that conducts electrical current and provides an open point in a circuit for isolation of circuit breakers, circuit switchers, power transformers, capacitor banks,

How to Rescue a Person from Electric Shock?
If a person receives an electric shock, it is the utmost duty of the observer to rescue the person. The first step is to disconnect the person immediately from the

What is Switching Station? | Working and Layout
What is a switching station? A switching station is a substation that does not contain power transformers and therefore does not change system voltage from one level to another. Switching

Substation Bus Configuration / Scheme: The Definitive Guide
In this article, you will learn different types of substation bus configuration and their application. The equipment and buses installed in the substation switchyard are arranged and connected in specific

How to Test Percentage Impedance of Transformer?
This article covers transformer impedance testing, one of the acceptances tests for new transformers, and a method for routine testing. The results of this test should compare directly to the

Electrical Substation: Equipment, Types, Components & Functions
An electrical substation is an integral part of a generation, transmission and distribution system. A substation can interrupt or establish electrical circuit, change the voltage, frequency or other characteristics of

Transformer Bushing Types : RIP Bushing vs OIP Bushing
Transformer bushing types are categorized based on their material, manufacturing, and design mainly into the following types: OIP (Oil-Impregnated Paper) Bushing RIP (Resin Impregnated Paper) Bushing RIS (Resin Impregnated Synthetic)

Measurement of Three Phase Power | Wattmeter Methods
This article explains the measurement of three-phase power in star connected or delta connecter load using the wattmeter methods. The power in a three phase load can be measured by

Circuit Breaker Definition, Working Principle and Arcing Phenomenon
Definition A circuit breaker means the device which breaks (Open) the circuit under the abnormal condition and protects the system from hazards. The function of a circuit breaker is to isolate

4 Major Types of Electrical Substations
The assembly of the apparatus used to change some characteristic (e.g. voltage, a.c. to d.c., frequency, p.f etc.) of electric supply is called a sub-station. The four major types

Current Transformer (CT) – Construction and Working Principle
A current transformer (CT) is a type of transformer that is used to measure AC current. It produces an alternating current (AC) in its secondary which is proportional to the AC

Ideal Transformer and Practical Transformer
Ideal Transformer An ideal transformer is one that has no winding resistance no leakage flux i.e., the same flux links both the windings no iron losses (i.e., eddy current and

Properties of Good Transformer Oil
Even though the basic functions of the oil used in transformers are heat conduction and electrical insulation, there are many other properties which make a particular oil eminently suitable. Properties of good transformer

Why we need Power System Protection?
In this article, you will learn the importance of protection in the modern power system and why we need power system protection. It is fair to say that without discriminative

Introduction to Gas Insulated Substations / Switchgears (GIS)
Gas-insulated substations (GIS) have been used in power systems over the last three decades because of their high reliability, easy maintenance, small ground space requirement, etc. This article is an

Low Voltage Switchgear
As per IEC 60947, switchgears with rated voltages up to 1000 V ac and 1500 V dc are termed as low voltage switchgear. The term ‘switchgear’ is a generic term

Substation Earthing System Design
We have already given an introduction to substation earthing system in an article published earlier. Today we are going to discuss the design of substation earthing system. Before 1960s the

Transformer Oil Testing : Video Training
Transformer oil testing is just like a blood test in the human body. A blood test provides a doctor with a wealth of information about the health of a patient.

IEC 61850 – Features and Advantages
IEC 61850 is a standard for the design of electrical substation automation. It has been defined in cooperation with manufacturers and users to create a uniform, future-proof basis for the

Basic Relays – Electromagnetic Attraction and Induction Relays
Most of the relays used in the power system operate by virtue of the current and/or voltage supplied by current and voltage transformers connected in various combinations to the system

Solid State Relays (Static Relays)
What is a Static Relay? There are two basic classifications of relays – Electromechanical Relays and Solid State Relays (Static relay). One main difference between them is electromechanical relays have

All Day Efficiency of Transformer
Definition The ratio of output in kWh to the input in kWh of a transformer over a 24-hour period is known as all day efficiency. ηall-day = Output in kWh