Analysis and Research on Energy Storage System for Offshore Mobile Drilling Platforms

To address the problems of power grid frequency fluctuation, unavailable winch reverse power, and high energy consumption on offshore mobile drilling platforms, and to meet the requirements of “dual carbon” goals and green development of deep-water oil and gas resources, this paper investigates the platform energy storage system. It analyzes the working principles of the Power Conversion System (PCS), bidirectional DC/DC converter, and Energy Management System (EMS), and completes the adaptive design for offshore platforms. By comparing the performance of supercapacitors, lithium iron phosphate (LFP) batteries, and flywheel energy storage, supercapacitors are determined as the optimal selection. Based on the data of Well BZ19-4-A25H in the Bohai Bay, the electric energy consumed by the winch braking resistor per well is calculated. On this basis, a reverse power recovery system integrated with supercapacitor banks is designed, and its working process is clarified. This system can recover electric energy per well, reduce diesel consumption and carbon emissions, and also has the functions of peak shaving, valley filling and auxiliary frequency modulation to stabilize the power grid. It provides a solution for the power stability, energy conservation and emission reduction of offshore platforms, and can be further optimized by combining with offshore wind power and solid-state batteries in the future.