| 摘要 |
PURPOSE:To realize an economical operation by a method wherein an evaluated cost of a total loss of a transformer and an evaluated cost of auxiliary machines losses are calculated and the number of coolers to be operated is determined by this calculated value. CONSTITUTION:A load loss detecting current transformer 20 and an oil temperature detecting measuring device 21 are provided to a transformer 3 to be cooled. Detection output signals from the current transformer 20 and the temperature measuring device 21 are introduced into a calculator 23 through A/D converters 24, 26. The signals from both the detectors are introduced into a load evaluation device 28 in the calculator 23 and it is judged whether the transformer is operating under the rated capacity. When the operation is under the rating, the signal is transferred to the load loss calculator 30. The load loss value calculated by the calculator 30 and the no load loss of the transformer 3 proper and the loss of auxiliary machines enough to cool former two losses are compared by a comparator 31 and the operation condition signal by which the signal of operating condition with which the evaluated cost becomes minimum is transmitted. The evaluation device 32 determines the number of coolers to be operated in accordance with the signal. The operation instruction is given to the necessary number of coolers 1 determined by the evaluation device 32 by an operation instructing device 34. |
