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Availability Assessment of the HVDC Converter Transformer System

Authors:
  • Svenska kraftnät, Sweden, Stockholm

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This paper presents a reliability assessment of the HVDC converter transformer system (CTS) comparing different component models and configurations. The CTS model is based on the Markov modelling approach, which is shown to be well suited for these relatively small systems. The failure rate data in the models is based on statistical surveys by OGRE. A number of scenarios are calculated in order to evaluate the impact of the availability of the CTS given different conditions. The result shows on the benefit in availability using a spare transformer, particularly at a close location of the HVDC station.
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... Conventionally, most of the researchers working on reliability evaluation of HVDC transmission systems have employed traditional methods, which can be categorized as analytical [11][12][13][14][15][16][17] and simulation methods [18][19][20][21]. Each method has advantages and disadvantages, so the appropriate method is determined by the type of evaluation desired as well as the nature of the problem. ...
... c P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P (1) 3(1) 1 (1) 2(1) 3(2) 1 (1) 2(2) 3(1) 1 (1) 2(2) 3(2) 1 (2) 2(1) 3(1) 1 (2) 2(1) 3(2) 1 (2) 2(2) 3(1) 1 (2) 2(2) 3(2) 1 (1) 2(1) 3(1) 1 (1) 2(1) 3(2) 1 (1) 2(2) 3(1) 1(2) 2(1) 3(1) 1(2) 2(2) 3(1) sys (16) where the final result is equal to the given in Eq. (11) after a rearrangement of the equation. ...
... The column vectors of the resulting C l matrix represent the event vectors for the component events, i.e. C 1 , C 2 , … C 16 . The vector p is obtained following the procedure previously described and its size is (2 16 × 1). ...
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