Electric power industry
The method of symmetrical components is used to calculate the normal and emergency modes of the electric network. The method represents an any mode (even asymmetric) as a composition of three separate symmetrical ones:✅ Positive sequence “1”.✅ Negative sequence “2”.✅ Zero sequence “0”. To use the method, it is important that the longitudinal impedances Z1,
Usually, AC cable lines are up to 10 km long. However, in some cases the length can reach 50 km or even 100 km. In such cases, the cable line has a significant capacitance, which must be charged and discharged following the sine wave of the alternating voltage of the AC network. This alternating current
The previous post was about the reasons why switching lines with shunt reactors (SR) can cause damage of the line breaker B1. Theoretically, several options can be proposed to solve the problem. Let’s start with controlled switching devices (CS, see scheme). CS can be used only in cases when each phase of the breaker has
The photo shows a 500 kV SF6 circuit breaker (B1), which was damaged during the energizing of the 500 kV overhead line. The cause of the accident was the presence of a 500 kV shunt reactor (SR) on the line, which compensated about 100% of the capacitive reactive power of the line. Let’s look at exactly
This is an amazing tower of a 110 kV multi-circuit overhead transmission line. It was built in the Kaliningrad region, former USSR. Although I love electric cables and lead a Linkedin group on them, I still have to admit that it is difficult to make something so bright and attractive out of a cable buried
You know, a lot of efforts are being spent all over the world to have energy green, however, sometimes it seems to me that the “blue sky” government program would even be much more important. I mean there are a number of countries in the world where even in large cities electricity supply to consumers
This is a line of voltage class 1150 kV, which was built about 35 years ago in Kazakhstan. It was a unique project for the whole world to transfer electric power of several thousand megawatts from the Ekibastuz coal basin (Kazakhstan) to the center of the USSR. However, after the collapse of the Soviet Union,