Mid-life Upgrade for DC-DC Converter

A global oil and gas company operating advanced subsea production systems, where reliable power delivery and stability are essential for maintaining safe and continuous operations.

The DC-DC Converter Module plays a critical role in subsea systems, ensuring stable power conversion for components such as valve controllers and sensor networks.

As system requirements evolved, the existing module faced growing limitations related to performance, compliance, and component availability.

Increasing power demands introduced challenges in meeting electromagnetic compatibility (EMC) standards, while some key components became obsolete and unavailable. Any upgrade had to preserve compatibility with the existing system architecture and operate reliably in harsh subsea environments, making a full redesign impractical.

To maintain system performance and continuity, the solution needed to:

• improve EMC performance under increased power requirements
• replace obsolete components with modern equivalents
• maintain compatibility with existing subsea systems
• ensure thermal stability and operational reliability
• pass rigorous qualification and compliance testing

The goal was to enhance performance and compliance without disrupting the existing system design.

A targeted mid-life upgrade approach was implemented to modernize the DC-DC converter while preserving its integration within the existing system. Instead of redesigning the entire module, the focus was on improving key performance areas and addressing component obsolescence.

Advanced EMI suppression and filtering techniques were introduced to ensure compliance with EMC standards while maintaining efficient thermal behavior. The electronics hardware design work also included replacing obsolete components with custom-designed alternatives to support long-term availability and improved performance.

This approach illustrates how component selection, simulation, and testing contribute to extending the lifecycle of legacy electronic systems. Our guide to the hardware design process explains these engineering considerations in more detail.

Technology stack:

• LTSpice / PSIM / Power Stage Designer for simulation
• Altium Designer for hardware design
• Custom magnetics manufacturing
• EMC and environmental testing frameworks

The modernized converter maintains stable power delivery across subsea systems, ensuring consistent operation of connected components.

Enhanced filtering reduces electromagnetic interference, allowing the module to operate within required compliance standards. Custom components ensure long-term availability while maintaining compatibility with the original system design.

Key capabilities:

• Improved EMC performance with advanced EMI suppression
• Replacement of obsolete components with custom designs
• Stable power conversion under increased load
• Compatibility with existing subsea architecture
• Optimized thermal and electrical performance
• Compliance with subsea qualification standards

The upgrade improved the stability and reliability of power delivery across subsea systems, reducing the risk of failures in critical components. By maintaining compatibility with existing infrastructure, the solution avoided complex integration challenges and minimized operational disruption.

Improved compliance also ensured readiness for future deployments in demanding environments.

The solution delivered measurable improvements across key areas:

• Extended product lifecycle, delaying the need for replacement
• Improved compliance, meeting strict EMC and qualification standards
• Reduced operational risk, through stable power delivery
• Avoided redesign costs, by upgrading instead of replacing
• Ensured component availability, through custom replacements
• Enabled future deployments, in demanding subsea environments

The upgraded module provides a reliable and scalable foundation for future subsea systems, allowing the client to continue operating and expanding without major infrastructure changes. The approach can be replicated for other components facing similar performance or obsolescence challenges.

Can an obsolete subsea DC-DC converter be upgraded without redesigning the whole module?

Yes. A targeted mid-life upgrade improves key performance areas and addresses component obsolescence while preserving the module's integration in the existing system. In this project, InTechHouse replaced obsolete components with custom-designed alternatives and kept compatibility with the existing subsea architecture, which avoided redesign costs and extended the product lifecycle of the DC-DC Converter Module.

How can a subsea DC-DC converter meet EMC standards under increased power demands?

Advanced EMI suppression and filtering techniques bring the converter within EMC standards while maintaining efficient thermal behavior. Filtering reduces electromagnetic interference, so the module operates within required compliance standards under increased load. In this project, InTechHouse checked the upgraded subsea DC-DC converter with EMC and environmental testing frameworks, and the results include meeting strict EMC and qualification standards.

What engineering work goes into a mid-life upgrade of subsea power electronics?

Simulation, hardware design, and custom magnetics manufacturing are the core work streams. Component selection, simulation, and testing together extend the lifecycle of legacy electronic systems. In this project, InTechHouse simulated the converter in LTSpice, PSIM, and Power Stage Designer, designed the hardware in Altium Designer, and kept stable power conversion for valve controllers and sensor networks in the subsea system.