The secrets behind dynamic PM-driven winches

Since Seaonics personnel delivered the first electric winches in 2002 we have supplied hundreds of electric driven winches for both the Offshore Energy and Ocean Harvesting industry. With more than 20 LARS systems with PM driven ROV winches and more than 40 trawl systems in operation Seaonics has become one of the leading suppliers of electric driven winches.

Published: 06/11/2020 Updated: 06/12/2020
Why electric?

The initial change from hydraulic to AC powered winches was driven by the need for more energy efficient equipment with lower maintenance costs and end users who saw the benefits of electric over hydraulic. These early adopters have enjoyed the benefits of lower energy consumption, lighter equipment, a quiet workplace and lower service cost. And they have come back for repeat projects.


The change from AC to PM

For LARS systems we delivered PM driven systems already in 2012 and these systems have supported tens of thousands of ROV operations over the years. Feedback from these systems and end-users are high system reliability and outstanding performance which have enabled efficient ROV-operations and vessel utilization.  

The benefits of being able to utilize high torque on low RPM, combined with low total inertia, enables rapid acceleration to adjust for even the smallest control deviance.  During ROV operations this has resulted in a very dynamic, precise winch with increased reliability. The experiences from these projects led the way to the change from AC to PM for Trawl winches. During a normal trawl operation with shooting-towing-heaving, the PM motors capabilities are a good fit, especially during the towing phase with high torque on low/zero RPM.



The development of the BigDrum™ winch

Niisa Trawl and Royal Greenland were the first customers who chose PM motors for trawl winches and it resulted in the Seaonics BigDrum™ trawl winch. The BigDrum™ winch is equipped with two to four PM motors, low gear ratio, redundancy and has a superior dynamic performance. We have actually had to limit the dynamic response as it was too dynamic! When you also add increased shooting and heaving speeds it is a winning combination for any fishing vessel. Ivan Olsen, Captain of Sisimiut, has worked with low pressure trawl winches for many years, but is now running a double-trawl system on Sisimiut with Seaonics PM-winches. His feedback is clear “The PM-winches from Seaonics have superior dynamic performance and have contributed to record catches for Sisimiut”.



So what the secret?

The secret is a mix of 20+ years of experience with electric driven winches, first-hand experience from fishing operations, continuous feedback from and collaboration with end-users and first class engineering, all gathered in Seaonics. Want to know more about electric, PM driven and dynamic winches and how they work in operation. Contact our Head of Global Service and Aftermarket Erlend Strand Farstad. Want to read more about some of Royal Greenlands record fishing check out this article.


Seaonics is a result of the maritime cluster on the West-coast of Norway, and our market position is the result of the trust and support from ships designers and ship owners. The result is world-class equipment and knowledge benefiting ship owners around the world and our local communities.


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