Coupling analysis of a new skin effect electric heat tracing system for deep water heavy oil pipeline

In order to ensure the safety of fluid flow in deep-water submarine pipelines, a safe and energy-saving built-in skin effect electric heat tracing technology was adopted as the thermal management strategy. By analyzing the multi-physics conditions of the electromagnetic field-temperature field in the heating state of pipelines, the corresponding control equations were derived, and the physical model was established using the transient electromagnetic-temperature coupling field of Ansys Workbench. Simultaneously, we calculated the equivalent parameters of the oil pipeline and heating cable as the load when the system is heated to different temperatures. Thus, the main circuit parameters of the power supply for the built-in skin effect electric tracing system were designed, thus providing the theoretical guidance for the key performance optimization. For regulating the output power of the built-in skin effect electric heat tracing system, the nonlinear active disturbance rejection control strategy was newly adopted to achieve closed-loop power regulation based on the Buck chopper, and the system has the advantages of fast dynamic response and strong anti-interference ability. Finally, the feasibility of the proposed control system was verified by simulation.