Category Archives for protection

How Circuit breaker works and arc initiation methods

Control circuit diagram of circuit breaker

What is Circuit breaker? A breaker is a device which is used to turn a circuit on or off during normal operating conditions and automatically breaks the circuit during abnormal conditions when heavy currents start flowing through the system due to some fault. How circuit breaker works ? Basically a circuit breaker consists of a […]

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In this article you will learn about location of reactors in power system and types of reactors used in power system and their applications along with diagrams. Advantanges and disadvantages of reactors in power system in different locations. Generator Reactors: When reactor is connected between bus bar and generator, it is called a generator reactor. […]

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Why reactors are used in power system and their types


INTRODUCTION TO REACTORS: A reactor is a coil which has large number of turns and whose ohmic resistance value is much greater. Reactors are used to limit the short circuit currents which can cause damage to the equipments of the power system. The additional reactance added in series with the system for protection, are called […]

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types of fault in power system

    A defect in a power system which causes the current to stop flowing through that system is known as fault. In other words, the interruption in the normal flow of current is said to be a faults. American institute of Electrical engineers defines the fault in a cable or a wire as: “The failure of insulation […]

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    per unit system calculation method

      Per unit and percentage quantities, In this article you will learn what is per unit system? Why we need to used per unit system in power system? How to convert actual values to per unit values? And formula’s of per unit system. When a fault occurs, abnormal currents flow through the system. These currents are […]

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      power system representation

        Power system representation, One line diagram another way Following methods are used to represent a power system: One line diagram Impedance diagram Reactance diagram 1.ONE LINE DIAGRAM: The symbolic representation of an electrical power system is known as one line diagram. A three phase power system is represented by a single phase power system. In […]

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          In the present modern era, the demand of electrical energy has greatly increased. Most of this energy is utilized in lighting, heating, household equipments, industrial machinery and in electric traction. The demand of electric supply is so high that in case of a faulty situation, the healthy system must be isolated from the fault in […]

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