Pennsylvanian firm VideoRay is using underwater remotely operated vehicles (ROVs) to protect the world’s busiest ports and waterways using power technology from Massachusetts-based Vicor.

The modular design and scalable, high-density power delivery enables variable payloads and precise manoeuvrability.

Port security and surveillance, mine countermeasures, and underwater search and rescue are all dangerous missions that should no longer put lives or vessels at risk. Where sustained, mission critical underwater inspection or exploration is required, ROVs can be the safest and most effective way to maintain security, support salvage efforts and uncover secrets of the ocean.

Video-equipped ROVs can reach hard-to-access underwater locations at extreme depths for extended periods. To be effective, ROVs require a robust, high-density power delivery network that enables the necessary thrust to withstand shifting ocean currents and provides a steady view of surroundings while having the space for payloads to accomplish mission-specific activities.

VideoRay tethered underwater ROVs can be deployed for round-the-clock operation at depths down to 305m, or 2000m in float mode, with power supplied from the host platform or vessel. Also in development is a battery-operated ROV that can sustain underwater operational uptime for up to eight hours, and allows for a slimmer, lighter tether devoted purely for video and communications transmission.

Among its many innovations, VideoRay offers an interchangeable, modular component ROV system residing on a single intelligent network. The system provides a flexible and customisable platform that can be easily adapted to specific missions, markets and payloads.

The ROVs are designed to handle difficult missions that have size, weight and deployment speed constraints. They are also distinguished by powerful thrust, longer tether lengths, higher resolution video and interchangeable modular systems.

To achieve these ROV capabilities, VideoRay requires a power delivery network architecture so it can design smaller ROVs with more power and greater manoeuvrability at greater depths. Among the many design factors at play is the modularity and power density of the on-board power components, key to enabling the scalable ROV portfolio of providing the flexibility to swap high-performance modules to accommodate evolving requirements with the added agility to customise ROVs quickly and easily for customers.

VideoRay relies on Vicor to meet requirements for power density, efficiency and low EMI noise in a manner that reduces the need for bulky heat sinking and EMI filter systems. This enables a sleek, power-dense system design that allows for efficient cooling while preserving board space for other value-add components.

The modular VideoRay flagship Defender ROVs have employed Vicor DCM series converters to produce lower-voltage power from 400V DC to energise all main thrusters and control electronics inside the subside vehicle. The DCM DC-DC converters suit the Defender due to their high power density in a small footprint that also integrates monitoring and auto-shutdown features. The DCM accommodates a wide input voltage range to allow for large voltage drops on longer tethers.

The fixed-ratio Vicor BCM bus converter used in the VideoRay Pro 4 main controller converts rectified AC from the host ship to 72V DC in a compact fashion, delivered to the ROV via the tether to power it.  It uses heat sinking and active cooling for easier thermal management. High-voltage BCM modules in the power converters help generate the tether voltage, with heat sinking and active cooling for thermal management in a waterproof enclosure.

BCMs use the Vicor proprietary SAC sine amplitude converter topology, an efficient resonant-tank based DC-DC converter architecture, to accomplish bidirectional fixed-ratio DC-DC conversion. With input voltage from 36 to 800V and transforming voltage by various K factors to support a wide range of applications, some BCMs also have integrated PMBus telemetry, control and EMI filtering.

BCMs can reach peak efficiencies of 98% and can have their inputs in parallel into high-power arrays and outputs connected in series and/or parallel to achieve even higher output voltages and/or currents than a single module.

For battery-powered ROVs, VideoRay is using Vicor high-power, high-density, 97% efficient PRM buck-boost converters with constant-current and constant-voltage control for battery management. Featuring a zero-voltage switching architecture, PRM buck-boost regulators accommodate a wide input voltage range and provide a regulated, adjustable output voltage.

VideoRay is leveraging Vicor power modules across its growing ROV portfolio in a manner that scales to meet needs. Working together, VideoRay and Vicor have innovated a modular, high-density power delivery network architecture that enables VideoRay to develop smaller yet more powerful ROVs capable of operating continuously at great depths, with round-the-clock run time.

Founded in 1999, VideoRay builds underwater ROVs for a wide range of applications, including search and rescue, security and anti-terrorism, mine detonation, offshore oil and gas, and wind-farm infrastructure inspection, hull and pier inspection, aquatic research, maritime salvage and more.

Vicor is headquartered in Andover, Massachusetts.