Load Factor, Diversity Factor and Capacity Factor

What is Load Factor? Load factor is defined as the ratio of average load to the maximum demand for a given period of time. Thus mathematically, load factor may be written as Load Factor = Average Load / Maximum Demand Load factor is generally calculated for a day, month or year. If we calculate the … Read more Load Factor, Diversity Factor and Capacity Factor

Why Power Transmitted at High Voltage?

Electric Power is always transmitted at the possible highest voltage level. Earlier it was transmitted at 220 kV, then after advancement of technology it raised to 400 kV. But these days in India, the highest voltage level at which electric power is transmitted is 765 kV. Well, have you ever think of why do we … Read more Why Power Transmitted at High Voltage?

Effect of Unsymmetrical Spacing of 3 Phase Line Conductors

When the distance between the three phase line conductors are not same i.e. they are not spaced equally from each other then it is said to have unsymmetrical spacing. Unsymmetrical spacing of overhead line conductors give rise to unequal voltage in the individual phases at the receiving end even though the flow of current in … Read more Effect of Unsymmetrical Spacing of 3 Phase Line Conductors

Critical Disruptive Voltage

What is Critical Disruptive Voltage? Critical Disruptive Voltage is defined as the minimum phase to neutral voltage required for the Corona discharge to start. Basically corona discharge is the current discharge in the air. Therefore it is quite obvious that surrounding air shall breakdown for corona to start. From the basic of Electrostatics, we can … Read more Critical Disruptive Voltage

Advantage and Disadvantage of Corona

Corona has many advantages and disadvantages. Therefore for designing a transmission line, care must be taken to have a balance between the advantage and disadvantage of Corona. Advantage of Corona Following are some of the advantage of corona: The effective diameter of power conductor increases due to Corona. How? Actually, due to corona, the air … Read more Advantage and Disadvantage of Corona

Surge Impedance and Surge Impedance Loading

Surge Impedance is the characteristic impedance of a lossless transmission line. It is also called Natural Impedance because this impedance has nothing to do with load impedance. Since line is assumed to be lossless, this means that series resistance and shunt conductance is negligible i.e. zero for power lines. This means that, Series Resistance R … Read more Surge Impedance and Surge Impedance Loading

Characteristic Impedance of Transmission Line

Characteristic Impedance of a Transmission line is defined as the square root of ratio of series impedance per unit length per phase and shunt admittance per unit length per phase. If z and y are series impedance and shunt admittance of line, the characteristic impedance Zc is given as Zc = √(z/y) Where z = … Read more Characteristic Impedance of Transmission Line

Grounding / Earthing Transformer

Grounding Transformer is often called Earthing Transformer. The purpose of Grounding Transformer is to artificially create neutral point. In Delta Connected Transformer or Generator where neutral point is unavailable or in case where neutral point is inaccessible, Grounding Transformer is used to create neutral point. Constructional Design of Grounding Transformer Grounding Transformer is so designed to … Read more Grounding / Earthing Transformer

3rd Harmonic Leakage Current Test of Lightening Arrestor

3rd Harmonic Leakage Current Test is performed on Surge / Lightening Arrestor (LA) to monitor its healthiness. Need for Monitoring of LA The need for monitoring of Metal Oxide Lightening Arrestor (LA) arises as its deterioration may lead to heating and consequent blasting. Though LA being cheaper can be replaced but blasting of LA can … Read more 3rd Harmonic Leakage Current Test of Lightening Arrestor

Why Primary Current Injection Test Required?

Many times I have been asked to justify why to conduct primary current injection test at rated current of circuit? Why to invest money in purchasing Primary Current Injection Kit? This is why I decided to write a topic on the importance of primary current injection test. After reading the topic you will be able … Read more Why Primary Current Injection Test Required?