To increase cost efficiency in wind turbines, the wind industry
has seen a significant rise in power density and an increase in the overall size of geared components. Current designs for multimegawatt turbines demand levelized cost of energy (LCOE) reduction, and the gearbox is a key part of this process. Since fatigue failures nearly always occur at or near the surface, where the stresses are greatest, the surface condition strongly affects the gear life. Consequently, an improved surface condition effectively avoids major redesign or increased material cost due to an increase in part size. Additional finishing methods such as shot peening (SP) and superfinishing (SF) significantly increase the gear load capacity, but these effects have not yet been adequately considered in the current ISO 6336 standard or in any other gear standards. The combination of SP followed by SF will be described here as an “improved gear surface” (IGS).
This study deals with the modeling and consideration of misalignments in planetary gearboxes in the optimization and design process. Procedures for taking into account misalignments in cylindrical gearboxes are standardized and established in industry. Misalignments of central elements like carrier, sun gear or ring gear in planetary gearboxes, cause varying contact positions and variable loads, depending on the angular position of the central elements. This load, which is variable over the circumference, is not taken into account in the standardized procedures, despite its effects on the loads on the gears.
In the wind power industry, the reliability of powertrain components plays a major role. Especially in multi-megawatt offshore applications, an unplanned replacement of drivetrain
components can lead to extremely high costs. Hence, the expectation of wind farm operators is to forecast the system reliability. Under the leadership of the VDMA (Mechanical Engineering Industry Association), the standardization paper 23904 "Reliability Assessment for Wind Turbines" was published in October 2019.
Historically, wind turbine gearbox failures have plagued the industry. Yet an effective oil analysis program will
increase the reliability and availability of your machinery, while minimizing maintenance costs associated with oil change-outs, labor, repairs and downtime. Practical action steps are presented here to improve reliability.
Having outlasted the worldwide Great Recession, the Global Wind Energy Council (GWEC) forecasts a constant growth in wind energy, i.e.: "increase in worldwide capacity to 460,000 MW by 2015."
The turbines are still spinning.
They’re spinning on large wind farms
in the Great Plains, offshore in the
Atlantic and even underwater where
strong tidal currents offer new energy
solutions. These turbines spin regularly
while politicians and policy makers—
tied up in discussions on tax incentives, economic recovery and a lot of finger pointing—sit idle. Much like the auto and aerospace industries of years past, renewable energy is coping with its own set of growing pains. Analysts still feel confident that clean energy will play a significant role in the future of manufacturing—it’s just not going to play the role envisioned four to five
years ago.
Gear flank breakage can be observed on edge zone-hardened gears. It occurs, for example, on bevel gears for water turbines, on spur gears for wind energy converters and on single- and double-helical gears for other industrial
applications.
This article describes some of the most important tests for prototypes conducted at Winergy AG during the product development process. It will demonstrate that the measurement results on the test rig for load distribution are in accordance with the turbine measurements.
We talked energy efficiency with some
major players in the lubricants industry—
but with a focus on their products’
impact regarding energy efficiency of
gears and gearboxes in wind turbines.
Faithful Gear Technology readers may recall that our July 2009 issue contained an update of the deliberations
provided by Bill Bradley. Now, almost two years later, there is an ISO/IEC wind turbine gearbox standard out for draft international standard ballot (ballot closes 2011-05-17).