How to Improve the Service Life of Oil Immersed Type Transformer

In order to ensure the service life of the oil immersed type transformer, the circuit must be protected. Here are some introductions of the oil immersed type transformer from the manufacturers: as long as the oil-immersed transformer circuit does not have any problems during its operation, the use and life of the transformer can be guaranteed. Next, let's take a look at the circuit protection of oil-immersed transformers.

For the main transformer of the workshop substation with the high voltage side of 6-10KV, it is usually equipped with over-current protection with time limit. If the time of the over-current protection action is greater than 0.5-0.7s, the current quick-break protection should also be installed. For the oil-immersed type transformer with a capacity of 800KV · A and above and the oil-immersed type transformer in a workshop of 400KV · A and above, gas protection shall be installed as required.

For the transformers with a capacity of 400KV · A and above, when several units are operated at the same time or in a single operation and used as a backup power source for other loads, overload protection should be installed according to the possible overload conditions. Overload protection and gas protection act on the signal when there is a slight fault, while the other protections, including the gas protection, generally act on the trip when there is a serious fault.

For the main transformer of the plant's total step-down substation with a high voltage side of 35KV and above, overcurrent protection, current quick-break protection and gas protection should also be installed. When there is a possibility of overload, overload protection should also be installed. However, if the capacity of a single-operation transformer is 10000KV · A and above and the capacity of each transformer at the same time is 6300KV · A and above, it is required to install the longitudinal differential protection to replace the current quick-break protection.