Remote Monitoring of On-Load Tap Changer Switching Cycle Based on Acoustic Sensing

Remote monitoring of On-Load Tap Changer (OLTC) switching cycle based on acoustic sensing is presented in this work. Two methods for indirect OLTC switching feedback are considered and implemented. The first one is based on the transient load of the OLTC drive induction motor during the switching process, the second method uses the acoustic noise during switching measured on the top shield. Both methods are suitable for distributed IIoT monitoring applications. The results will be used for diagnostics database assembly, establishment of the conditions and extraction of logical rules of the facility according to the given criteria set. The compliance with these criteria and rules will be cross- correlated for most common malfunctioning cases. This way they can be used for OLTC early damage prognostics, prevention or repair planning.