Variations in gear fatigue life for different wind turbine braking strategies

Conference · Sat Jun 01 04:00:00 EDT 1991

OSTI ID:5828926

McNiff, B P ^[1]; Musial, W D ^[2]; Errichello, R ^[3]

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1. Second Wind, Inc., Somerville, MA (USA)
2. Solar Energy Research Inst., Golden, CO (USA)
3. GEARTECH, Albany, CA (USA)

A large number of gearbox failures have occurred in the wind industry in a relatively short period, many because service loads were underestimated. High-torque transients that occur during starting and stopping are difficult to predict and may be overlooked in specifying gearbox design. Although these events comprise a small portion of total load cycles, they can be the most damaging. The severity of these loads varies dramatically with the specific configuration of the wind turbine. The large number of failures in Danish-designed Micon 65 wind turbines prompted this investigation. The high-speed and low-speed shaft torques were measured on a two-stage helical gearbox of a single Micon 65 turbine. Transient events and normal running loads were combined statistically to obtain a typical annual load spectrum. The pitting and bending fatigue lives of the gear teeth were calculated by using Miner's rule for four different high-speed shaft brake configurations. Each breaking scenario was run for both a high- and a low-turbulence normal operating load spectrum. The analysis showed increases in gear life by up to a factor of 25 when the standard high-speed shaft brake is replaced with a dynamic brake or modified with a damper. 9 refs., 9 figs., 3 tabs.

• Research Organization: Solar Energy Research Inst., Golden, CO (USA)
• Sponsoring Organization: DOE; USDOE, Washington, DC (USA)
• DOE Contract Number: AC02-83CH10093
• OSTI ID: 5828926
• Report Number(s): SERI/TP-257-3984; CONF-9009107--7; ON: DE91002161
• Country of Publication: United States
• Language: English

Related Subjects

17 WIND ENERGY
170602* -- Wind Energy Engineering-- Turbine Design & Operation
BRAKES
DAMPING
DYNAMIC LOADS
FATIGUE
GEARS
MACHINE PARTS
MACHINERY
MATERIALS TESTING
MECHANICAL PROPERTIES
MECHANICAL TESTS
PERFORMANCE
SERVICE LIFE
STRESSES
TESTING
TORQUE
TURBINES
TURBOMACHINERY
WIND LOADS
WIND TURBINES