Method for detecting transformer winding state by using constant-current sweep frequency power source excitation

Abstract

The invention relates to system and method for detecting the transformer winding state by using constant-current sweep frequency power source excitation. A measurement and control analysis module controls sweep frequency power source and applies output constant-current sweep frequency excitation signals by an exciting transformer at a high-voltage side of the transformer to be detected; a vibration sensor measures vibration response signals of a transformer winding to be detected at different excitation frequencies; a vibration signal collector collects and preprocesses the signals measured by the vibration sensor; and the measurement and control analysis nodule carries out spectrum analysis to the received and processed vibration response signal data, displays and records a resonant frequency curve of the transformer winding on a frequency domain, compares with the resonant frequency curve previously measured and recorded as well as the vibration frequency curve of a transformer three-phase coil, and judges the state of the transformer winding to obtain the measuring result. The invention can effectively and sensitively detect the states of looseness or deformation of the transformer winding for prompt repair or replacement so as to avoid a fault of abrupt short circuit of the transformer caused by damage of the winding structure.

Description

technical field [0001] The invention relates to a system and a method for detecting the winding state of a transformer by using a constant current sweeping power supply to excite vibration. Background technique [0002] The transformer is one of the most important equipment in the power system, and its operation stability has a great influence on the safety of the power system. With the increasing capacity of my country's power grid, the short-circuit capacity is also increasing. The huge electromagnetic force generated by the surge current formed by the short-circuit of the transformer outlet poses a serious threat to the mechanical strength and dynamic stability of the transformer winding. At present, the operating environment of substation equipment and lines is not optimistic. The deformation of transformer winding caused by external short circuit is a relatively common fault in the process of transformer operation, which poses a great threat to the safe operation of the...

AI Technical Summary

Problems solved by technology

[0020] The test sensitivity of the frequency response method is higher than that of the short-circuit impedance method. However, due to the complexity of the frequency response waveform, the judgment of the winding condition requires more experience, and it is difficult to form a clear quantitative criterion. Therefore, no criterion has been formed so far.

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