Application of on-line monitoring of transformer winding deformation
Abstract: An on-line measurement system for transformer short-circuit reactance has been developed. The results of laboratory simulation test and substation trial operation show that the system has high accuracy and good stability, and the changes of transformer operating conditions and external factors have little influence on the measurement of reactance, which can provide real-time and accurate indication of transformer winding conditions in actual operation.
Keywords transformer winding deformation short-circuit reactance on-line measurement
0 Introduction
Because the transformer short-circuit impedance and its inductance component are related to the winding geometry and relative position, the winding condition can be analyzed by on-line detection of the transformer short-circuit reactance change [1]. An on-line measurement system for transformer short-circuit reactance is developed to determine the deformation of transformer windings.
3) Comparing the off-line and online measurement results after changing the taping (states 6 and 7), it can be seen that changing the taping has no effect on the accuracy and accuracy of the online measurement system, but it is different from the rated taping (state 2).
4) Comparing the online measurement results before and after changing the load size and power factor (states 2-4), it can be seen that these changes have no effect on the accuracy and precision of the system.
5) The measurement results (states 5 and 2) before and after continuous operation for 150 h show that the system has good stability and can meet the needs of online monitoring.
In addition, some factors affecting the low voltage pulse method (LVI) and frequency response method (FRA) are also investigated, such as the ground mode of the objects around the test site, the length of the lead and the position of the lead, etc. The measurement results are almost unchanged, indicating that the system has good repeatability and little influence of external factors.