Research on the Principle and Effectiveness Analysis of Online Monitoring of Transformer Windings Based on Multi-Point Injection

As an important part of the power system, the transformer bears the key task of power transmission and conversion, however, winding failure is often one of the main causes of transformer accidents, seriously threatening the stability and reliability of the power system, therefore, timely and accurate monitoring of the transformer winding status has become critical. Based on the main wiring diagram of a 110 kV substation, this paper verifies the effectiveness of sinusoidal excitation signals based on capacitance sensors, station transformers and voltage transformers injected at multiple points by constructing the RLC equivalent circuits of the transformer and its peripheral devices, determines the online monitoring scheme for the windings, and builds a test platform for transformer windings, and carries out the frequency response of transformer windings offline and online respectively, further to verify the effectiveness of the principle of online monitoring of transformer windings based on multi-point injection.