Equal Area Criterion and Out of Step Condition

Equal Area Criterion is the method of studying the Transient Stability of system of two machines or single machine connected to infinite bus. The study of Transient Stability tells us whether or not synchronism is maintained i.e. whether or not load angle δ settles down to steady state stable value after the clearance of fault … Read more

A Brief Introduction to PLCC Panels

Power Line Carrier Communication (PLCC) is used for the purpose of protection of line and communication between the two stations. Two different PLCC channels are used for the protection of a single line. This is the reason, you will notice that wave traps are normally installed in R and B phase of transmission line. The … Read more

Theory of Arcing Ground-Ungrounded System

Ungrounded System is one where the neutral is not connected to earth. Thus, neutral of ungrounded system is isolated. Arcing Ground is an electrical phenomenon in which the voltage of faulty phase fluctuates due to capacitive charging current. This arcing ground phenomenon is prevalent in three phase ungrounded neutral system. Don’t worry I will explain … Read more

Design Basis for Electrical Protection

Electrical Protection is considered as the heart of power system. Protection system should be such robust to isolate the fault in minimum possible time to minimize the equipment damage. The design of electrical protection is based on the following basic considerations: Adequacy The selected protection should be adequate to cover all types of faults and … Read more

Zero Sequence Filtering in Differential Protection

Zero sequence filtering is a concept used to eliminate zero sequence current component from the secondary current of Current Transformer used in Differential Protection of Transformer. This concept is useful in Transformer having earthed Star winding. What is the Need for Zero Sequence Filtering? Let us have a detailed discussion on this topic. For better … Read more