WTT Mechanical Systems & Drivetrain 2

Question 1

What is the primary function of a wind turbine's pitch system in the drivetrain context?

Accepted Answer

Adjust blade angle to control rotor speed and power output

Answer

The pitch system rotates each blade around its longitudinal axis to regulate aerodynamic forces, controlling rotor speed and power capture.

Question 2

Which type of coupling is most commonly used between the gearbox output shaft and the generator input shaft in a wind turbine?

Accepted Answer

Flexible disc coupling

Answer

Flexible disc couplings accommodate misalignment and dampen torsional vibrations between the gearbox and generator shafts.

Question 3

What does the term 'gear ratio' mean in a wind turbine gearbox?

Accepted Answer

The ratio of output shaft speed to input shaft speed

Answer

Gear ratio is the output shaft speed divided by input shaft speed, typically stepping up from ~15–25 RPM at the rotor to ~1,500–1,800 RPM at the generator.

Question 4

Which seal type is typically used on a wind turbine main shaft to prevent lubricant leakage while allowing rotation?

Accepted Answer

Labyrinth seal with radial lip seal

Answer

A labyrinth seal combined with a radial lip seal prevents grease or oil from escaping along the rotating main shaft without creating excessive friction.

Question 5

What is the likely cause if a wind turbine gearbox produces a high-pitched whine at rated speed but operates normally at low speed?

Accepted Answer

Gear tooth wear or misalignment at high-speed stage

Answer

High-pitched whine at rated speed typically indicates tooth wear, pitting, or misalignment in the high-speed gearbox stage where frequencies are highest.

(WTT) Wind Turbine Technician Certification Practice Test

(WTT) Wind Turbine Technician Certification Practice Test

WTT Mechanical Systems & Drivetrain 2