Global Underwater Hub Explores the Tech Behind CSS’ New Power Converter

For the last 10 years, Connector Subsea Solutions (CSS) has been developing breakthrough solutions to support the growing transition from AC to DC subsea power conversion and distribution.

As an industry leader in the supply of bespoke power and control systems to major offshore operators, CSS is now providing AC-DC and DC-DC power conversion solutions for a variety of subsea applications.

The increasing global focus on subsea electrification offers improved operational efficiency, reduced environmental impact, and increased flexibility for both the offshore oil and gas and renewable energy industries. It enables remote operation, automation, and integration of subsea processes, leading to cost savings, lower emissions, and greater resilience.

The shift from AC to DC power usage in subsea applications is driven by factors such as higher efficiency, reduced transmission losses over long distances, improved voltage stability, and potentially better integration of future renewable energy sources. DC power systems enable enhanced overall performance, reliability, and sustainability in subsea operations.

Latest Development: CSS Modular DC-DC Power Converter (MPC)

The CSS MPC is a high-voltage (HV) DC-DC step-down power converter system utilising multilevel technology that efficiently steps down a high (2 – 6 kV) DC voltage to a lower (300 – 700 V) DC voltage level. This is achieved by employing an innovative arrangement of multiple power electronic switching stages. Full electrical galvanic isolation ensures safe operations and higher reliability.

The innovative multi-level design of the MPC offers lower switching losses, excellent output stability, smaller size, scalability, and inherent fault-tolerant operation due to the modular structure. If an individual module fails, the converter can still operate with reduced capacity, avoiding complete system shutdown, enhancing reliability and availability of the subsea power system. The MPC can be easily scaled up to meet higher power requirements by installing additional modules (currently in 50kW steps). This scalability allows for flexible system design and future expansion without requiring significant modifications to the existing infrastructure or control philosophy. The fully isolated MPC system combined with integrated line isolation monitoring (LIM) capabilities provides improved safety, enhanced stability, mitigation of harmonics and interference, flexibility in grounding options, secure and efficient interconnections with enhanced reliability and reduction in cascading failures or disturbances.

CSS’ field proven MPC enables reliable power conversion, facilitating efficient step-down of high-voltage DC power to lower voltage levels, making it suitable for a wide range of applications such as subsea power systems and distribution, with a current focus towards new eROV and AUVs systems, as well as potential offshore renewable energy (ORE) technologies.

The conversion technology enhances power transmission over long distances with minimal losses, making it suitable for remote subsea installations, improving operational efficiency, reliability, and safety. CSS’ MPC and power distribution systems provide subsea equipment manufacturers the ability to engineer and deliver products to lead the next generation of subsea electrification.

Read the full article on page 33 of the GUH News Magazine.

Learn more by joining our presentation on this topic at the Subsea Expo conference, taking place on Thursday 22nd February 2024 in the P&J Live Arena, Teal Conference Room, between 10am – 12pm.

For more information on this technology, please contact Paul Hughes.