Selection of Surge Arresters: These are non-linear resistors in series with spark gaps which act as fast switches. A Selection of Surge Arresters or lightning arrester is shown in Fig. 8.24 and its characteristics are…
Insulation Coordination in High Voltage: Insulation Coordination in High Voltage - Electric power supply should ensure reliability and continuity to the utility concerns. Hence, the power lines and sub-stations are to be operated and protected…
Transmission Line Overvoltage Protection: Transmission Line Overvoltage Protection against natural or lightning overvoltages and minimizing the lightning overvoltages are done by suitable line designs, providing guard and ground wires, and using surge diverters. Switching surges…
Control of Switching Overvoltage: The Control of Switching Overvoltage and power frequency may be controlled by energization of transmission lines in one or more steps by inserting resistances and withdrawing them afterwards, Phase controlled closing…
Power Frequency Overvoltages in Power Systems: The Power Frequency Overvoltages occur in large power systems and they are of much concern in EHV systems, i.e. systems of 400 kV and above. The main causes for…
Switching Surges in Transmission Line: Till the time when the transmission voltages were about 220 kV and below, over-voltages due to lightning were of very high order and overvoltages generated inside the system were not…
Rectangular Travelling Wave: Reflection and transmission of a Rectangular Travelling Wave at junction points of unequal impedances in a transmission line are of great importance in transmission systems. Depending on the type of impedance at…
Transmission of Waves at Transition Points: Whenever there is an abrupt change in the parameters of a transmission line, such as an open circuit or a termination, the travelling wave undergoes a transition, part of…
Attenuation and Distortion of Travelling Waves: As a Travelling Waves moves along a line, it suffers both attenuation and distortion. The decrease in the magnitude of the wave as it propagates along the line is…
Classification of Transmission Lines: Classification of Transmission Lines are usually classified as Lines with no loss or ideal lines, Lines without distortion or distortion less lines Lines with small losses, and Lines with infinite and…