Today’s wind turbines are not your father’s windmill. These pieces of machinery need to fuse the physical turbine to electrical systems, software and  control mechanisms.

During a presentation to group of engineers and students in Upson Hall on Thursday, Rohit Shenoy discussed the difficult process of designing turbines.

The traditional way to produce this machine utilizes several specialized teams of engineers. One team may design the gear train, the turbine blades and other physical components. Another team may design the circuitry, and another may write the software.

This compartmentalized approach can lead to problems when the different systems fail to properly work together.

Shenoy is a representative from The Mathworks.  In addition to producing simulation software that may evaluate wind tubines, the software company produces MATLAB, a programming language used by many engineers.

Shenoy described issues for wind turbines.  For instance, in Denmark, high wind caused the blades of a turbine to spin faster than the turbine was designed, and the stresses caused the turbine to collapse.

“The braking system failed, and what it should have done was slow the turbine down and gone into a safe mode. Instead, it just kept spinning faster and faster,” described Shenoy.

Shenoy went on to explain that a MATLAB add-on called “Simulink” would have allowed the various groups of engineers to create computer models for each part. They could create an integrated model of the entire turbine. This approach, which is called “model based design,” is also used in the automotive and aerospace industries.

“The idea being that when everyone can share a common design environment, you can test for various issues and discover issues much earlier on in the process. The goal is really to do your design in an integrated fashion, do it at a system level,” said Shenoy.

This sort of simulation allows engineers to test physically what happens to the entire turbine under certain wind conditions and to test for errors. This software can adjust the angle of the model turbine blades by inserting an “ideal actuator” into the design.

An ideal actuator is a theoretical device that delivers a specified force at a desired rate. While creating such a device in the real world is impossible, the actuator’s behavior under a variety of conditions tells the engineers what the physical devices they design have to be able to do.

Once the engineers design a physical device, they can simulate it and compare it to the behavior of the ideal actuator. 

Simulation allows engineers to determine when to connect the turbine to the electrical grid. It is important to connect the turbine to the electrical grid when the wind turbine is turning within a certain range.  If the turbine turns too quickly, it may cause a spike in the power grid.  If the turbine turns too slowly, the turbine may draw power from the grid.

In order to solve this problem, engineers must figure out how much power is generated when the turbine is spinning.  This power depends on many variables, such as the particular gear train structure.

Computer modeling is the only tool engineers have to manage this problem because building an actual turbine, performing physical testing or using a wind tunnel are impractical ways to gather data.  Computer modeling is a vital solution to this engineering challenge.