go here Transistor Transistor is a three terminals (namely emitter, collector, base) three layer and two junction semiconductor device. It is used to amplify or process an electrical signal. A transistor consists of two two pn junctions formed either P type or N type semiconductor between a pair of opposite types. There are two types transistor. PNP […]

Bus-Bar Arrangements

follow site Bus-Bar Arrangements When a number generators or feeders have same voltage then there is necessity to connect all unit electrically, bus-bars are used as the common electrical component. In this article, we will discuss about different bus-bar arrangements. What is Bus-Bar? Bus-Bar are thick copper rods which is operate at constant voltage and carrying an […]

EMF Equation for Transformer

follow link EMF Equation for Transformer For drive an emf equation for transformer we will consider the case of an ideal transformer. An ideal transformer one which have no copper loss(I2R losses) and magnetic leakage flux. In other words, we can say that an ideal transformer consists of windings which have zero ohmic resistance and loss-free core. […]

Transformer on Load

Transformer on Load When some load is connected across the secondary of the transformer, then it is said to be transformer on load. The current I2 flows through load and secondary winding. The magnitude of current I2 depends upon the terminal voltage V2 and impedance of load. The angle between current I2 and voltage V2 […]

Advantages of HVDC Transmission

Advantages of HVDC Transmission The electric energy can be transmitted either by mode of ac or dc. Now in these days, ac supply is transmitted. But high voltage dc system is more superior to ac transmission system. In this article, we will discuss about advantages of HVDC transmission or high voltage dc transmission . These […]

Silicon Controlled Rectifier

Silicon Controlled Rectifier  (SCR) Silicon controlled rectifier belongs to thyristor family. SCR is used in industrial application. It is used for controlling high voltage in the order of 10KV and current in order of 3000A. It plays an important role in industries. In this topic we will discuss about what is an SCR, construction of […]

Vacuum Circuit Breakers (VCBs)

Vacuum Circuit Breakers (VCBs) Since vacuum offers highest insulating strength, so it can use as arc quenching medium. The circuit breakers that use vacuum as a arc quenching medium, known as vacuum circuit breakers (VCBs). Construction of Vacuum Circuit Breakers It consists of two contact one is fixed and other is movable and these contacts […]

EMF Equation for DC Machine

EMF Equation for DC Machine DC machine may be either works as a dc motor or dc generator. EMF equation is important for both. In case of DC generator an induced emf is called generated emf and in case of DC motors generated emf is called Back or Counter emf  The DC generator is rotate […]

Induction Type Over Current Relay

Induction Type Over Current Relay Induction type over current relay works on the induction principle. This relay operates when current in the circuit exceeds the predetermined value. These relays are used on ac circuits only. Construction This relay has two electromagnets. Upper magnet Lower magnet The upper magnet has three limbs and primary and secondary […]

Parallel Operation of Alternators

Parallel Operation of Alternators When the number of smaller units is connected in parallel instead of installing a large unit is called parallel operation of alternators. There are numbers of reasons, connecting alternator in parallel such as cost become less, maintenance and repair, efficiency and reliability of the power system. All the alternator of the […]