Real-time Monitoring Method of Insulation Status of Photoelectric Composite Submarine Cable based on Thermoelectric Coupling

The existing approach for monitoring the insulation state of photoelectric composite submarine cables primarily relies on detecting the current of the cable protection layer. However, this conventional method suffers from limited monitoring accuracy due to the absence of parameter identification processing for the cable. As a result, there is a need to improve the monitoring methodology by incorporating robust parameter identification techniques to enhance the accuracy of insulation state evaluation. In this regard, a real-time monitoring method based on thermoelectric coupling is proposed to monitor the insulation status of the photoelectric composite submarine cable. By constructing an equivalent composite circuit model and a thermodynamic function, a thermoelectric coupling model is constructed and used to identify the parameters of the submarine cable; by extracting the frequency extremes in the spectral values of the submarine cable current signal, an equivalent insulation characteristic function is constructed to realize the determination of the insulation state. The proposed method is verified for the insulation state monitoring effect in the experiment. The experimental results show that when the proposed method is used to monitor the insulation state of the photoelectric composite submarine cable, the calculated partial discharge quantity has a small error, and the monitoring accuracy is high.