Hoyer developing a fit-for-purpose motor for a wind application

Wind turbine failures can result from both external and internal factors. Internally, mechanical issues, such as motor or bearing failures, can have a ripple effect, causing other components to malfunction, which increases the likelihood of extended downtime and costly repairs. The turbine relies on the correct motor for each of its key systems. If even one motor is unsuitable for the conditions, it can lead to significant inefficiencies and higher maintenance demands.

Analysing the customer’s challenges

The gearbox is a vital component in the wind turbine, providing precise speed control that maximises power generation efficiency. Recently, a customer of Hoyer experienced a reduced operational lifespan of both bearings and motors due to excessive vibration stemming from the gearbox and the oil pump system that lubricates it. These vibrations led to premature motor replacement and increased maintenance requirements for the gearbox.

The oil pump system plays a critical supporting role in gearbox maintenance. When it fails, it can lead to costly and time-consuming repairs. As Jonas Løgstrup Hansen, Energy Segment Manager of Hoyer, explains:

“Product reliability is always important, but in the wind industry, it is absolutely key. In this specific case, a failing motor would quickly lead to reduced power generation and, in the worst case, turbine downtime. This results in significant losses for the end user and is therefore a key driver of this product's development.”

Tailored solution for specific requirements

To address the specific challenges faced by the customer, Hoyer developed a motor engineered to withstand the excessive vibration and temperature rise associated with the gearbox and oil pump system in a wind turbine. This motor was designed to operate continuously across a wide range of voltage conditions while maintaining its reliability under extreme mechanical stress. By focusing on these key factors, Hoyer ensured the motor would deliver a longer operational lifespan and greater reliability.

“The motor features a unique creep-free bearing design with O-rings and a special tolerance arrangement, constraining the bearings against fretting effects and movement, significantly extending its lifespan. We also optimised the motor’s electrical design to ensure it could handle voltage variations beyond standard requirements without performance loss,” says Marcelo Hellman, CTO of Hoyer.

Marcelo continues: “Additionally, the cooling system was enhanced using CFX tools to design a fan with an increased blade count and special blade shape, optimising airflow and reducing temperature rise by up to 10K. To ensure the motor meets the operational demands, we conducted rigorous testing alongside our customer, including over 1,000 start-stop cycles.”

At Hoyer, the commitment to customer satisfaction is paramount. This project underscores Hoyer’s ability to develop innovative, fit-for-purpose solutions that drive operational success in demanding industrial applications.