Rated Power Oscillations (10s timescale)

Understanding rated power oscillations

What is the purpose of the turbine issue check?

• A given turbine is exhibiting fluctuations (oscillations) in the rated power signal. These fluctuations may be periodic oscillations, or they may be changes in the rated power, unrelated to wind speed changes, on the order of 10s of seconds or faster.
• If a turbine is operating below rated power, and it is not expected, this will directly impact turbine output. Causes may include different software types, incorrect parameter changes, or sensors that need to be updated.

Can you see this in 10-min data? 

• No, as we can see below Turbine 708 exhibits significant and frequent reductions in power, but the 10-minute power curve (right) does not highlight the magnitude of these events

How do you identify this issue?

• This issue is identified through analysis of the high-frequency data (left) where the frequent reductions are identified

How can you tell the issue is corrected?

• The reductions in power are eliminated (and would look like the turbine 707 in the above image)
• In this example, the turbine had high temperature due to converter fan issues causing the turbine to reduce power to cool down
  • The impact of this issue was 2.4% AEP on the turbine
  • Correction increased revenue by $32,000/Yr for the turbine