A.C. Pilot Relaying

Pilot Wire Schemes—Phase and Amplitude Comparators—Effect of Load Current—Multi-terminal Lines—Pilot Wire Limitations—Pilot Supervision—Phase Comparison Carrier
  • A. R. van C. Warrington


THEORETICALLY, unit protection provides almost perfect selectivity but, when applied to lines and cables, it is less effective because the pilot channel or link between the terminals, together with the coupling equipment in the case of h.f. carrier, introduces amplitude and phase angle errors in the quantities compared (28) (140). This link may be pilot wires or high frequency carrier channel superimposed on the overhead power lines.


Internal Fault Half Cycle Carrier Signal Fault Current Phase Comparison 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Albert Russell van Cortlandt Warrington 1968

Authors and Affiliations

  • A. R. van C. Warrington
    • 1
  1. 1.The English Electric Company LimitedStaffordUK

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