Powering Offshore Renewable Energy Research: Powertrain Research Hub

Published 26 August 2020

With industry moving towards larger wind turbines, we have an opportunity to significantly contribute to reducing the cost of turbine technology. It is essential to maximise this opportunity by tackling the challenge of improving powertrain component reliability and availability. By developing the next generation of powertrain components, and improving their lifespan, we can significantly reduce the related operations and maintenance costs and subsequently minimise the number of human interventions for potentially dangerous turbine repair work at sea.

At ORE Catapult, we have a strong track record in powertrain testing, research and development, including a test programme for GE Renewable Energy to advance its next generation turbine technologies, including the Haliade-X 12 MW, the most powerful wind turbine in the world to date.

We are conducting vital research that is set to transform key areas of the offshore renewable energy sector. So far in this research blog series, we have dived into the research world of electrical infrastructure for offshore wind. In this second blog of the series, we’ll take a closer look at the role our Powertrain Research Hub plays in enhancing the UK’s world-leading offshore wind industry.

ORE Catapult's 15MW Powertrain Test Facility at the National Renewable Energy Centre in Blyth.

Powertrain Research Hub

The Powertrain Research Hub (PTRH) is a £2.4million, five-year research partnership between the ORE Catapult and the University of Sheffield that aims to address key offshore wind industry challenges in powertrain development and design.

ORE Catapult’s powertrain team is at the forefront of powertrain testing, validation, innovation and research. Our experienced powertrain specialists, engineers and project management teams work with clients to enhance and validate their advanced and complex wind and tidal turbine powertrain systems. We support the development of powertrain component and systems to accelerate the introduction of new technologies to market, thus increasing competition and reducing capital expenditure (CAPEX). Our research enables intellectual property rights generation and licensing of solutions that can be developed with, and add value to, the existing test and demonstration assets of ORE Catapult.

As of March 2020, there are three active PhD projects with plans to enable 12 PhD studentships and six years-worth of postdoctoral research activity.

Here is a snapshot of just some of the innovative research projects that are taking place as part of our powertrain research hub.

Case Study I: Robust Modular Machines for Offshore Wind Applications

There has been a dramatic increase in offshore wind production over the past decade, with this trend expected to continue at an even greater level through the 2020s as the UK strives to achieve 40GW of offshore wind by 2030. However, a number of challenges still exist, most notably in addressing reliability concerns due to the harsh operational environment and the subsequent high repair and maintenance costs. Therefore, it has long been recognised that reliability improvement and hence the reduction in maintenance costs remain pivotal in enabling future growth and investment.

In order to overcome these challenges, this research project proposes robust modular machine topologies, with such machines having a segmented stator with flux gaps between adjacent stator segments. There are several advantages for such a modular design including:

  1. Improved electromagnetic performance such as increased torque/power density, reduced torque ripple, and increased efficiency;
  2. A simplified winding process and also an increased slot fill factor;
  3. Reduced iron material waste and up to a 70% reduction in iron lamination materials; and
  4. Improved fault tolerant capability due to physical, electromagnetic and thermal insulation between adjacent segments, leading to reduced operation and maintenance costs

Case Study II: Damage and Failure in Wind Turbine Pitch Bearings

Pitch bearings of modern, large-scale offshore wind turbines are subjected to high axial forces and bending moments while they are standing still or oscillating at low speeds. There is no established international standard that currently exists to determine pitch bearing service life accurately. This inaccuracy is mainly due to insufficient understanding of the key damage mechanisms.

This research project aims to investigate and understand the failure mechanisms observed in wind turbine pitch bearings due to small oscillatory movements. A clearer understanding of false Brinelling and fretting corrosion development in pitch bearings will contribute to predicting their service life more accurately. It will also lead to an improvement in pitch bearing designs, particularly for larger-scale wind turbines using larger bearings.

Pitch bearing failures due to false Brinelling and fretting corrosion became predominant after the implementation of individual pitch controller (IPC), which allows each blade to oscillate independently. This has resulted in a significant increment of small amplitude oscillations, the operating condition under which these wear mechanisms prevail. A worn pitch bearing can result in the faulty operation of the pitch control, which can cause an inefficient power optimisation, and unexpected loads in other components.


Learn more about the specific research projects that are taking place under the Powertrain Research Hub here. To find out more information on all of our research hub activity, visit the Research section of our website or please get in touch at

Anna Southall, Academic Engagement Plan Manager