The CJC Transformer Oil Unit is an oil care system for drying of insulating oil and insulation in transformers. The insulation of the transformers is dried indirectly via the insulating oil during operation of the transformer (on-line drying).
The Transformer Oil Unit simultaneously removes water, particles and oil ageing products from the insulating oil. The filter pump draws the humid insulating oil from the transformer and pumps it through two up to three filter housings (2-stage or 3-stage filtration). In first both filter housings only water is removed from the insulating oil. In the last filter housing are also removed solid particles and oil ageing products from the insulating oil. Dried and cleaned the insulating oil is lead back to the transformer. There, it picks up further humidity from the paper insulation generated because of the age-related degradation of the cellulose (depolymerisation). By this means, gradually not only the insulating oil but also the transformer insulation is dried. During operation, the water content is measured by two sensors at the filter inlet and outlet. The difference between the measured values indicates the quantity of the removed water.
DRYING OF THE INSULATION INSIDE TRANSFORMERS
The approach of conditioning the transformer insulation with the CJC Transformer Oil Unit is the continuous operation on the running transformer (24/7). The insulating oil indirectly dries the paper insulation. The oil is dried in continuous operation, and the paper insulation gradually releases the water to the dried oil led back from the fluid care unit. This way of indirect drying is the most gentle method for the ageing cellulose of the transformers.
FINE FILTRATIONOF INSULATING OIL
The CJC Fine Filter Insert also removes solid particles. The oil is slowly pumped through the depth filter insert, whereby the dirt particles are retained in the numerous cavities between the fibres of the filter insert (filter degree: 3 µm absolute, 1 µm nominal). The CJC Fine Filter Insert offers an extreme large dirt absorption capacity due to the long contact time of the oil with the filter material at high retention rates. In this way, a CJC Fine Filtration ensures a sustainably high dielectric strength and increases operational reliability.