Session: Turbine Modeling & Technology

Paper Number: 164905

164905 - A Novel Seismic Test on a Wind Turbine Nacelle: The Preliminary Findings 

Abstract: 

Taiwan's latest energy policy outlines a plan to achieve a 15.1% share of renewable energy in power generation by 2025, with an offshore wind power installation capacity of 5.7 GW. Hence offshore wind farms are being actively developed to achieve energy self-sufficiency and net-zero carbon emissions. However, natural hazards such as typhoons and earthquakes pose potential threats to wind farm assets and power supply stability.

According to internationally recognized standards, seismic loads are considered alongside other loads such as wind, waves, and currents to enhance structural integrity and reliability. Therefore, relevant design standards focused on the supporting structures of wind turbines and site inspections, with less emphasis on critical components inside nacelles or offshore substations. Furthermore, since earthquakes are regional events, seismic design and verification requirements must adhere to local regulations. As a result, seismic or vibration testing descriptions in related documents are often explanatory or optional, with few state mandates for specific tests. Instead, product standards referenced by type certification documents specify that critical components have to undergo specific seismic or vibration tests under relevant environmental conditions. This typically refers to environmental testing methods provided in the IEC 60068 series standards, with testing parameters provided in the product standards of each component. However, the seismic testing parameters are not clearly defined in these standards, as they are influenced by varying site seismic conditions, structural characteristics, and installation environments. As a result, the actual seismic behavior of critical components inside the nacelle remains unclear, making it challenging to fully understand the seismic demands placed on these components.

This study employed a decommissioned onshore wind turbine to conduct a series of shake table experiments, using the complete nacelle as the test specimen. Instead of testing the entire supporting structure, including the 45-meter tower, only the nacelle was mounted on the shake table, which’s table motions replicate seismic responses at the top of the tower under artificial ground motions based on the requirements of domestic building code and strong motion records nearby. This approach was necessary, as testing the full wind turbine structure would not have been feasible. The realistic seismic behavior of the nacelle components was observed in these tests. The monitoring data helped identify potential weak points and contributed to the development of a numerical analysis model for nacelle components. By comparing experimental data with simulations, the study aims to develop a reliable numerical simulation method for verifying seismic performance, addressing the trend of increasing size of critical components in the future.

Presenting Author: Bai-Yi Huang National Center for Research on Earthquake Engineering

Presenting Author Biography: The presenter, Dr. Huang, is the assisant researcher of the National Center for Research on Earthquake Engineering, Taiwan, and major in structural dynamics and earthquake engineering. His research interests include evaluating and improving the seismic performance of the nonstructural components such as the equipment, suspended pipeline or ceilings through experimental and analytic methods.

Authors:

Bai-Yi Huang National Center for Research on Earthquake Engineering
Wei-Hung Hsu National Center for Research on Earthquake Engineering
Juin-Fu Chai National Center for Research on Earthquake Engineering
Fan-Ru Lin National Center for Research on Earthquake Engineering