The control of the transformer live status represents the capture and the adaptation different data which bring some information about its parameters. It realizes with aim prevention potential breakdowns or defects in the work of supply transformers. In practice the control realizes by using observation over difference between wait and real value of the transformer parameters.
Present day the transformer is one of the most important part of the electrical system over delivery and allocation of the electric energy. The breakdowns in its work can arise which the result of different causes. For example the puncture of the insulation, short circuit, disturbances with different nature, insufficient technical operations, overwork, failures etc.
Ones of the most important stages of the transformer live status are:
- Thermal model testing.
- Lysed gases testing.
- Frequency characteristic testing.
- Measurements of the partial discharges.
Thermal model testing
The term of the transformer work is defined its capability for diffusion of the warm. If to level real and observation working temperatures that can exact to diagnose the state of the transformer. If the function of warm ejection is disturb that the results can visible some time. The isolations is deteriorate with time. It is unwanted. Thermal modeling of the transformer is the development of the mathematical model which predict the change of the transformer working temperature with thermal analyze dealing. The receiving model can be used for the temperature definition of the transformer oil and the highest possible temperature which the isolation of the winding can outstay.
Lysed gases testing
The gases are the result of the hard isolation materials and transformer oil decomposition. The intensification of the advent process can to takes place over corona, partial discharges, thermal warming, short circuit or spark jump. This phenomena can to find over the analyze of hydrocarbon gases, hydrogen and carbonic oxide which are present in the oil. Every kind of the gases can to show about some fault in the transformer work. The live concentration and relative some gases allow to predict the rise of the errors and defects in the transformer work.
Frequency characteristic testing
When the current of the short circuit in transformer is appeared the mechanical construction of the windings is incurs the groundbreaking mechanical strains which send for the deformations. The frequency characteristic analyze provides an opportunity to the real deformations of the windings which arise caused by the short circuit current. This method consists of the measurements of the windings resistance after the supply the harmonic voltage in the frequency wide diapason for the transformer in.
Measurements of the partial discharges
The partial discharges arise when the value of the local electrical field is more than some maximum meaning. The local disruption arises. The sum influence of this factors results to the retrogradation of the isolation. Exist the measurements which allow to detect partial discharges and to control the continuity of the isolation. The partial discharges are the impulses of the current in the terminal of the transformer. Its nature ride on the type of the isolation, real defects, measuring instrument and detectors.