摘要 |
A pumping station feeds hydraulic energy to a grid or raises water from a low level to a high level. It includes, in particular, a transformer connected between an alternator and a grid, with a circuit breaker between the transformer and the grid. It further includes resistance for limiting the surge current through the transformer. This resistance lies in the range of 500 ohms to 100,000 ohms and is inserted for a period lying in the range 15 milliseconds to 19 milliseconds when the circuit breaker is closed, and a controller for ensuring that the circuit breaker closes on the unloaded transformer only at an instant that is no more than 1.2 milliseconds from an extreme value in the grid voltage.
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