Definition Short Circuit Ratio, or SCR, is the ratio of field current required to generate rated voltage under open circuit condition, to the field current required to circulate the rated armature current under three phase short circuit condition. It is an important quantity of synchronous...

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July 13, 2018 admin
Electrical Machines
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Zero Power Factor Characteristics Zero Power Factor Characteristics (zpfc) of synchronous generator is a plot between the armature terminal voltage and field current for a constant value of armature current and speed. A purely inductive load is connected across the generator terminal to achieve zero...

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July 12, 2018 admin
Electrical Machines
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The main purpose of compensating winding is to nullify the effect of armature reaction on the main field flux under the pole faces in DC machine. Due to the effect of armature reaction mmf, the flux distribution under the pole faces is distorted which leads...

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July 11, 2018 admin
Electrical Machines
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DC motor is an electromagnetic device which converts electrical energy into mechanical energy. DC power input is converted into mechanical power at the shaft motor. This article describes the construction of DC motor. There is no difference in the construction of DC Motor and Generator....

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July 5, 2018 admin
Electrical Machines
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Thevenin’s Theorem is the most used and useful approach to solve electrical networks. This is not a new way or approach rather it’s the same conventional way what we use to solve electrical networks but in an organized manner. Let me explain why this is...

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July 3, 2018 admin
AC Circuit
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1 Unit Electricity is the amount of electrical energy consumed by a load of 1 kW power rating in 1 hour. It is basically measurement unit of electrical energy consumption in Joule. 1 kWh (kilo watt hour) and 1 Unit are same. 1 kWh is...

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June 23, 2018 admin
AC Circuit
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The major difference between Instantaneous and Definite Time Overcurrent Relay lies in their operating time. The former operates instantaneously while the latter one operates after a definite time. Both Instantaneous and Definite Time Overcurrent Relay senses an over current in the circuit and gives tripping...

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June 22, 2018 admin
Power System Protection
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Torque equation of DC Motor gives the amount and nature of electrical torque Te developed whenever it is taken into service. Basically the performance of DC machine centers around two equations. One is EMF equation and another is Torque Equation. Therefore, understanding of torque equation...

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June 21, 2018 admin
DC Machine, Electrical Machines
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Definition: AC Generator is an electrical machine which converts mechanical energy into electrical energy. The input supply of AC Generator is mechanical energy which is supplied through some prime-mover and the output is alternating energy in the form of alternating voltage & current. In this...

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June 19, 2018 admin
Electrical Machines
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We know that torque equation in synchronous motor or generator is directly proportional to the stator filed strength, rotor field strength and the sine of angle between them. This is true for all rotating electrical machine. If Fs, Fr and λ be the stator field...

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June 18, 2018 admin
Electrical Machines
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