How to ensure the safe operation of Power Current Transformer

The requirements of Power Current Transformer in terms of product selection, inspection before putting into operation, sealing modification, oil injection, etc. are similar to those of voltage transformers. In addition, we also need to master some explosion prevention measures of Power Current Transformer. First, check whether the lead joints in the primary terminals of the transformer are in good contact.

The lead joints of the primary terminals of the Power Current Transformer should be in good contact, and the contact area should be kept sufficient to prevent the Power Current Transformer from overheating failures. The L2 terminal and the expander cover should be equipotentially connected to prevent potential suspension. In addition, there should be anti-rotation measures for the crucible drawn from the secondary line to prevent the internal lead from twisting due to external operations.

When the dielectric loss measured by the Power Current Transformer before and during operation is abnormal, it should be comprehensively analyzed with the obvious change in temperature or the test voltage has risen from 10kv to Um/root 3, and the increase exceeds ±0.3%. run. When the result of chromatographic analysis is abnormal, it is necessary to follow a comprehensive analysis to investigate its growth trend. If the data grows rapidly, attention should be paid.

In order to avoid the breakdown of the capacitor core at the bottom of the Power Current Transformer to expand the scope of the accident, attention should be paid to the installation direction of the primary terminal L1 and L2 and the polarity connection of the secondary winding to ensure the normal operation of the busbar differential protection. run. According to the development of the power grid, pay attention to the calculation of the short-circuit current at the location of the Power Current Transformer. When it exceeds the dynamic thermal stability current value of the transformer nameplate, it should be replaced in time.

On-line monitoring items for Power Current Transformer mainly include measuring the capacitance of the main insulation and the dielectric loss factor tgδ, and measuring the insulation resistance and dielectric loss factor tgδ of the final screen insulation. They are effective for detecting insulation defects.