Pump issues
Hydraulic Oil Contamination – particles
Particles in hydraulic oil change how the pitch system behaves under load. They increase wear risk in pumps and valves and can reduce pressure stability over time. If the trend continues, it may contribute to lost wind energy and shorter service intervals.
Understanding the Problem
Why do particles in hydraulic oil matter?
Particles circulate through the pump and control components where tolerances are small and forces are high. Even when the turbine appears to operate normally, contamination can accelerate wear and gradually change system response. The objective is to reduce the circulating particle load and restore oil cleanliness to a stable level.
Typical symptoms
Rising particle levels in oil analysis
Oil reports show an increasing contamination trend over time.
Oil cleanliness outside the expected range
Cleanliness classification shifts compared to baseline or historical results.
Faster filter loading
Filters require replacement more often or show heavier loading than expected.
Changing differential pressure across filtration
Restriction behaviour shifts as particle capture increases.
Haze or visible residue in samples
Samples show sediment or particulate residue on inspection.
Pressure stability becomes less consistent
Small fluctuations appear during pitch activity or holding phases.
Pump behaviour becomes more demanding
Duty cycle increases as the system compensates to maintain expected performance.
Solution
Oil filtration
Oil filtration reduces particle contamination by continuously cleaning the hydraulic oil during operation. The filtration method captures fine particles throughout the filter material, allowing effective removal without restricting oil flow. This helps stabilise oil condition and reduces abrasive wear in pumps and control components. The focus is long‑term oil cleanliness rather than short‑term correction.
