Tricky but Easy Electrical Engineering!
SCR / Thyristor is a four layer three junction device. It mainly consists of interleaved layers of P and N layers. It can block Voltage of either polarity but conducts current only in one direction that is from Anode to Cathode under normal working of forward biasing. Basically to forward bias an SCR we need … Read more
Transposition of Conductors refers to the exchanging of position of conductors of a three phase system along the transmission distance in such a manner that each conductor occupies the original position of every other conductor over an equal distance as shown in figure below. Advantages of Transposing Transmission Line: When conductors are not transposed at … Read more
Let us consider a 3-phase induction motor first and see how it rotates. A 3- phase supply given to the armature of Induction Motor produces a rotating magnetic field. This rotating magnetic field rotates at synchronous speed Ns = (120xf)/P This rotating magnetic field links to the rotor coils and induces voltage which in turn … Read more
The working principle of Three phase Induction Motor is basically based on the principle of mutual induction as in case of transformer. The major difference between them is that transformer is static in nature i.e. it doesn’t have any moving parts whereas Induction Motor is a dynamic one. Another difference between a Transformer and an … Read more
For understanding the role of Interpoles, we need to understand the effect of armature reaction in the DC Machine. The effect of armature mmf on the main field flux is to distort the main field flux and to reduce the net main field flux. The figure below, shows the effect of armature mmf on the … Read more
The concept of system grounding is extremely important, as it affects the susceptibility of the system to voltage transients, determines the types of loads the system can accommodate, and helps to determine the system protection requirements. The system grounding arrangement is determined by the grounding of the power source. For commercial and industrial systems, the … Read more
Insulation Classes based on the temperature it can sustain is classified into the following classes: The following are brief explanations of these insulation classes: Class-Y Insulation: Class-Y insulations can withstands a temperature of up to 90°C and it is typically made of cotton, silk, or paper. Class-A Insulation: Class-A insulations can withstands a temperature of … Read more
Load curve is the variation of load with time on a Power Station. As the load on a Power Station never remain constant rather it varies time to time, these variations in load is plotted on half hourly or hourly basis for the whole day. The curve thus obtained is known as Daily Load Curve. … Read more
As we know that Star & Delta Connection only possible in 3 phase system, so in our domestic system it is not possible, because generally all house hold electrical equipment are designed with single phase supply. Difference between Star & Delta: Star Connected System: Star connection is used where we require Neutral terminal to obtain … Read more
First we will describe what avalanche breakdown is. Avalanche breakdown occurs at p-n junction which is moderately doped and has a thick junction means have depletion layer width high. Avalanche breakdown occurs when we apply high reverse voltage across the p-n junction. As we apply more and more reverse voltage across the junction, the electric … Read more