Accurate simulation and analysis of the dynamic behavior of wind turbine subsystems requires a robust process to determine the load cases acting on the wind turbine components. LMS has developed an integrated approach to determine load cases based on simulation or operational testing.
Simulation-based loads prediction
Key design decisions in the early development stage have a major impact on the performance envelope of a wind turbine. To guide these decisions, it is extremely important to efficiently predict the transmission of loads between key components like gears, shafts and bearings, while taking the flexibility of these components into account.
The simulation approach based on LMS Virtual.Lab models the wind turbine system as an assembly of both rigid and flexible bodies derived from Finite Element modal analyses. The forces applied on the blades are propagated through the whole mechanism and the reaction forces on the component of interest are calculated. Virtual.Lab predicts the loads and deflections in different parts such as bearings, gear wheels, shafts and the housing. This provides an in-depth understanding of the dynamic behavior of the system.
Test-based loads characterization
Accurate measurements to determine load cases during real-life operation of the wind turbine represent a crucial step in the validation of virtual simulation models. LMS offers the required measurement and analysis systems, and the specific expertise to perform a test-based load characterization on a complete wind turbine during operation. Specific sub systems like the transmission can be tested in controlled laboratory conditions. Through a selective number of measurement points, engineers can visualize the deformation shapes of the gear turbine components under critical conditions as a function of frequency.
Dedicated gear analysis
To enable accurate calculation of the dynamic loading conditions and hence guarantee a reliable durability analysis, LMS Virtual.Lab offers a dedicated gear tooth contact element featuring e.g. the variable stiffness of the gear mesh. To assess the effects of shaft misalignment and the influence of tooth crowning, LMS Engineering Services pioneered an innovative approach taking the elastic tooth deformation as well as the micro-geometry into account within the multi-body simulation model. This approach delivers highly accurate and reliable results, without dramatically increasing simulation time. In both cases, the simulation model gives extensive insight into weak spots and possible problems in terms of vibrations, strength, force or durability.
