Optimization of subsea production control system layout considering hydraulic fluid pressure loss

Abstract

Historically, layout optimization of the Subsea Production Control System (SPCS) has primarily emphasized equipment construction costs, frequently overlooking the influence of the seabed's three-dimensional terrain on hydraulic pressure loss during power distribution. Such neglect can escalate maintenance costs throughout the oil and gas field's lifespan. This article presents an advanced SPCS layout optimization approach that addresses hydraulic pressure loss. A multi-objective optimization model, accounting for the intricate seabed three-dimensional terrain and obstacles, was developed for the multi-level Star-Tree structured SPCS. This model integrates parameters such as construction costs, pressure loss, and pipeline routes. By merging the strengths of NSGA-II (Non-dominated Sorting Genetic Algorithm II) and Lazy Theta*, a novel hybrid algorithm has been proposed. This algorithm is adapted at determining the optimal position for the Subsea Distribution Unit (SDU), refining the pipeline connectivity topology, and minimizing pressure loss, thereby identifying superior laying paths. In a case study featuring an SPCS with 20 Subsea Control Modules (SCM) and one Floating Production Storage and Offloading (FPSO) unit, the method's efficacy in reducing hydraulic pressure loss was demonstrated in simulation results. The findings of this research hold promise as a pivotal decision-making instrument during the SPCS design phase, providing profound theoretical insights for layout design.