Transmission Line Performance – Calculation

Transmission Line Performance is determined by two parameters. Those parameters are Voltage Regulation and Transmission Efficiency. In this post we will be discuss and evaluate the performance of short transmission line. As we know that the effect shunt capacitance of line is neglected for short transmission line. Therefore, for the sake of study and analysis … Read more

ABCD Parameters of Transmission Line

ABCD parameters are generalized parameters of transmission line. These parameters are quite helpful for calculation and analysis of transmission line. In any four terminal network, the input voltage and current can be expressed in terms of output voltage and current provided the network should be passive, linear and bilateral. Fortunately, a transmission line is a … Read more

Underground Cable – Introduction and Construction

An underground cable essentially consists of one or more conductors covered with suitable insulation and surrounded by some protective layer. Normally, electric power can either be transmitted using over head lines or underground cables. But the use underground cable offers a variety of advantages. Some of the advantages are listed below. It is less liable … Read more

Calculation of Cable Capacitance

Cable capacitance is the formation of capacitance between the charged core or conductor and the earthed lead sheath. Therefore it is quite important to have an idea of how the cable capacitance varies or the factors affecting its value. Calculation of Cable Capacitance A single core cable is similar to two long co-axial cylinders having … Read more

Current Chopping in Circuit Breaker

What is Current Chopping? Current Chopping in circuit breaker is defined as a phenomena in which current is forcibly interrupted before the natural current zero. Current Chopping is mainly observed in Vacuum Circuit Breaker and Air Blast Circuit Breaker. There is no such phenomena in Oil Circuit Breaker. Current chopping is predominant while switching Shunt … Read more

Resistance Switching in Circuit Breaker

Resistance Switching in Circuit Breaker refers to a method adopted for dampening the over voltage transients due to current chopping, capacitive current breaking etc. In this method, a shunt resistance is connected across the contacts of circuit breaker. How does Resistance Switching Work? Let us consider a circuit and connect a shunt resistance R across … Read more

SF6 Circuit Breaker – Construction, Working Principle and Types

In Sulpher Hexafluoride or SF6 Circuit Breaker, sulpher hexafluoride (SF6) gas is used as an insulating and arc quenching medium. SF6 gas has many superior properties which makes it perfect for arc quenching.Sulpher Hexafluoride or SF6 Circuit Breaker is most popular and widely used breaker. This type of breaker is mostly used for EHV systems like … Read more

Symmetrical Fault and Short Circuit kVA

Symmetrical Fault in Power System refers to kind of fault which leads to short circuit of three phases. This may be either short circuit of three phases or three phases to ground fault. In symmetrical fault, fault currents in phases are symmetrical in the sense that their magnitudes are equal and they are equally displaced … Read more