Tricky but Easy Electrical Engineering!
Final Value Theorem is used for determining the final value of a Laplace domain function F(s). Though we can always transform a time domain function into Laplace domain to apply Final Value Theorem. According to Final Value Theorem, final value of a function i.e. value of function f(t) when t→∞ is given as, Final Value … Read more
Initial value Theorem is a very useful tool for transient analysis and calculating the initial value of a function f(t). This theorem is often abbreviated as IVT. The limiting value of a function in frequency domain when time tends to zero i.e. initial value can easily be calculated using initial value theorem. This theorem can … Read more
Current Transformer is an instrument transformer which steps down high value of current to a low value of current suitable for measurement devices. It is widely used in power system for measurement and protection purpose. We cannot think of power generation, transmission or distribution without using Current Transformer. Construction of Current Transformer (CT): There are … Read more
In job interview often interviewer asks some numerical this is quit tricky and easy to answer without going into much calculation. In this post, I am going to discuss 3 most asked numerical questions in job interviews. These 3 questions are picked from my personal experience. Question No. 1 Find the current flowing through the … Read more
Geometrical Mean Radius GMR is basically the Geometric Mean of distances between the strands of a conductor. It is the fictitious radius of conductor having no internal flux linkage but only external flux linkage. To understand the concept of GMR and its calculation, it is very important to understand the calculation of inductance of Single … Read more
What is Meant by Over Reach? To understand the meaning of over reach, let us take an example of double circuit line in which one line is out of service and earthed at both end by Earth Switch. In the figure below, the distance relay is supposed to protect the line 1 due to its … Read more
Inductance is the property of a conductor due to which it opposes a sudden change in current through it and a basic electrical parameter like resistance and capacitance. Inductance is defined as the total flux linkage per unit current. To analyse the electrical behavior of circuit, it is very important to have knowledge of all … Read more
Energy Meters are one of the important instrument to account for energy imported / exported in an industry. In Power Generating Stations, the cumulative reading of such energy meters are used for the calculation of total Million Units (MUs) of energy exported. On the basis of MUs, total revenue generated by the Station is calculated. … Read more
Ring Main Unit,RMU is a compact, enclosed and sealed type of Switchgear used for medium voltage power distribution. It is a complete Switchgear in itself. A complete Switchgear means, assembly of required switching devices, protection device as well as metering device. RMU of different voltage (mostly 12 kV and 24 kV) and current ratings are … Read more
These days mostly Numerical Relays are used for protection purpose instead of conventional Electromechanical Relays. In fact, Numerical Relays offer a variety of protection as well as trouble shooting features. A single Numerical Relay can provide many protection unlike conventional Electromechanical Relays. A single Numerical Relay can have provision of Overcurrent, Earth Fault, Over-voltage protection … Read more