OLTC Fault Vibration Detection Based on Fiber Bragg Grating Sensing

The on-load tap changer (OLTC) of a power transformer plays a crucial role in power systems by stabilizing the voltage at load centers, regulating reactive power flow, and enhancing grid dispatch flexibility. Mechanical failures are the primary type of OLTC faults. Compared to traditional accelerometers, Fiber Bragg grating (FBG) sensors offer advantages such as excellent insulation properties, immunity to electromagnetic interference, and high sensitivity. To enhance the sensitivity of FBG vibration sensing, a cantilever beam structure was designed. Additionally, an OLTC fault vibration detection method incorporating an FBG sensor was proposed. A full-scale OLTC fault simulation platform was built at Shandong Taikai Transformer Co., Ltd., where fault signals were successfully collected. Experimental results demonstrate that the FBG sensing system designed in this study can effectively detect vibration signals associated with OLTC faults in power transformers, laying the foundation for future applications in fault type identification and fault severity classification for transformer OLTCs.