MR TAPCON, Руководство по эксплуатации

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8 Operation
Maschinenfabrik Reinhausen GmbH 2020 185 3587317/21 EN TAPCON
®
Limiting conditions If one of the tap changers reaches an end position (Pos<, Pos>, Pos< Fol-
lower or Pos> Follower), before the desired tap stagger level is reached,
both tap changers remain in a lower tap stagger level.
If the tap position of both on-load tap-changers is to be changed due to the
voltage regulation (e.g. 1, Fo1) and one tap changer has al-
ready reached an end position, the tap stagger level will be reduced.
Example
The following example demonstrates a possible switching sequence in the
tap stagger parallel operation method. Here, it is assumed that the on-load
tap-changers can be switched to the positions 1...12.
1. To start, the desired tap stagger level is 0; both on-load tap-changers are
in tap position 8.
2. The desired tap stagger level 8 is selected. Both on-load tap-changers
perform tap-change operations simultaneously until the desired tap stag-
ger level is reached. The circulating reactive current increases with each
tap-change operation. Because both on-load tap-changers switch simulta-
neously, the voltage of the transformers remains constant. Finally, the
master is in tap position 12 and the follower in tap position 4.
3. Due to voltage fluctuations in the grid (the voltage U leaves the band-
width), a "RAISE" tap-change operation is necessary. Because the master
is already in the highest tap position, the system must reduce the tap
stagger level in order to achieve the desired voltage change. To do so, the
master switches one level lower and the follower one level higher. The
master and follower then switch one level higher. The voltage returns to
the bandwidth.