Limitations of traveling wave relaying for overhead EHV transmission lines
Limitations of traveling wave relaying schemes for protection of overhead extra-high voltage transmission lines are investigated. A method of analysis of traveling wave phenomena for three phase transmission lines is developed in which the interdependent phase voltages and currents are decoupled into their modal counterparts, which are approximately independent. A time domain digital simulation program is used to solve the modal transmission line equations to obtain the fault induced traveling waves detected at the relay location. The frequency dependence of the aerial modes is ignored but their losses are included. A lumped element analysis method, originally developed for transient analysis of lossy coaxial cables, is adapted here to obtain approximate solution for the fault induced traveling waves of the ground mode. Excellent agreement is found between the results obtained by this method and frequency domain methods. This time-domain method offers more flexibility than frequency domain methods in dealing with general fault and termination boundary conditions. Limitations to traveling wave relays imposed by the boundary conditions at the line end and at the fault in conjunction with the slow transient response of standard transducers were investigated.
- Research Organization:
- Michigan Univ., Ann Arbor (USA)
- OSTI ID:
- 6958484
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
EHV & UHV-- (-1989)
24 POWER TRANSMISSION AND DISTRIBUTION
AC SYSTEMS
EHV AC SYSTEMS
ELECTRICAL EQUIPMENT
ELECTRICAL FAULTS
ENERGY SYSTEMS
EQUIPMENT
OVERHEAD POWER TRANSMISSION
POWER SYSTEMS
POWER TRANSMISSION
RELAYS
SIMULATION
TRAVELLING WAVES