Learn Electrical Engineering
A power transformer has high cost, large size, and complex design. So, identifying defects at the final stage of manufacturing can lead to significant delays, expenses, and operational challenges. Therefore, standards always recommend performing different tests and inspections during various stages of manufacturing. That means the standards always prefer to perform stage inspections of a … Read more
In this article, we are going to discuss the dead tank CT or dead tank current transformer, commonly referred to as a dead tank CT. Dead tank current transformers are not popular for very high-voltage systems like 220 kV and above. Utilities often use dead tank CTs in 33 kV systems. They prefer this design … Read more
A live tank current transformer (Live Tank CT) is a high-voltage current transformer. Here we place the entire current transformer at the top of the device. If we imagine a current transformer, the primary of the current transformer is nothing but the line conductor. Because of that, we connect the primary in series with the … Read more
Before entering the minimum oil circuit breaker (MOCB), let us recall our knowledge about the older version of the oil circuit breaker and which is the bulk oil circuit breaker. In a bulk oil circuit breaker,(BOCB) we use oil as the insulating medium. Also, we use oil as the arc-quenching medium. So, to serve both … Read more
In the early days, less 1910 or the early 20th century, most utilities used a bulk oil circuit breaker (BOCB) for high-voltage switching during that time. Earlier air circuit breakers served the purpose of switching high voltage and very high voltage current. But after the 19th century, engineers realized that mineral oil, or specially treated … Read more
Definition of Making Current The rated short circuit making current of a circuit breaker is the maximum peak current that the circuit breaker can close without any damage. It is the maximum peak current that a circuit breaker can make safely. Definition of Breaking Current The rated short circuit breaking current, on the other hand, … Read more
Engineers prefer to use silicone rubber composite insulators for transmission lines in areas with high pollution levels. In other words, these areas are among the most heavily polluted. These insulators normally have a creepage distance of 31 mm/ kV. The disc insulators used in heavily polluted areas also have a creepage distance of 31 mm/kV. … Read more
Before we discuss the use of disc insulators in high-voltage transmission lines, let’s understand the need for such insulators. Transmission lines operate at very high voltages such as 66 kV, 132 kV, 220kV, 400 kV, even 765 kV and more. So, the conductors used in these systems are also very heavy. To maintain proper ground clearance, we suspend these … Read more
Insulators Used in Overhead Transmission Lines In overhead transmission lines, insulators support the conductor on metallic tower structures. At the same time, they electrically isolate the high-voltage conductor from the metallic body of the supporting towers. In high-voltage overhead transmission lines, engineers typically install insulator strings at the tip of the cross arms of towers. … Read more
What is LBB Protection? Local Breaker Backup (LBB) Protection is a special protection scheme. This protection isolates a fault from the electrical power system when a circuit breaker fails to do so. When a fault occurs at a particular point in a power system, the primary protection relay associated with that part of the system detects … Read more