Online detection method for power transformer winding deformation and movement by impulse signal injection: Safety and feasibility validation

Power transformer assumes the important role in transportation of power energy; however, the initial faults inside transformer would eventually develop into catastrophic failure during its operation, which could result in the outage of equipment. Winding deformation and movement are considered to be the most common faults inside transformer. This paper proposed an online detection method for power transformer winding deformation and movement. As the key component, a capacitive coupling sensor mounting on the bushing was used to realize impulse signal injection. The safety of this sensor was primarily verified on a 110 kV bushing. In addition, the feasibility of the proposed method was validated through the experiment. The results show that the proposed method may reach the potential to detect winding deformation and movement when transformer is in service.