Power Transformer Protection

Types of Faults—Gas Relays—Differential Relays—Magnetising Inrush—Minimising of Effects—Relay Solutions—Grounding Transformers—Generator Transformer Units—Transformer Feeders
  • A. R. van C. Warrington


The power transformer is one of the most important links in a power system yet, because of its relatively simple construction, it is a highly reliable piece of equipment. This reliability, however, depends upon adequate design, care in erection, proper maintenance and the provision of certain protective equipment. Adequate design includes insulation of windings, laminations, corebolts, etc., bracing the conductors against short-circuit stresses and good electrical connections. Care in erection includes care to avoid physical damage, leaving or dropping anything foreign inside the tank (tools, nuts, etc.), making good connections and making sure the oil is clean and dry. Proper maintenance includes checking oil and winding temperatures, the cleanliness, dryness and insulation level of the oil and analysing any gas that may have accumulated above the oil.


Power Transformer Fault Current Protective Relay Ground Fault Inrush Current 
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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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