Wind-turbine drivetrains undergo severe transient loading during start-ups, shut-downs, emergency stops, and during grid connections. Load cases that result in torque reversals may be particularly damaging to bearings, as rollers may be skidding during the sudden relocation of the loaded zone. Seals and lubrication systems must work reliably over a wide temperature variation to prevent the ingress of dirt and moisture and perform effectively at all rotational speeds in the gearbox. Many wind-turbine gearboxes have also suffered from fundamental design issues such as ineffective interference fits that result in unintended motion and wear, ineffectiveness of internal lubrication paths and problems with sealing. Improving the resistance of future gearbox designs to all these issues is a key to the future cost of energy generated by wind turbines.

In its largest order to date, Danish wind turbine test specialist R&D Test Systems will develop the 30 MW powertrain and gearbox test bench for ZF Wind Power’s future “Test & Prototype Center” at Lommel, Belgium. Capable of simulating the multiplicity of wind loads that a nacelle powertrain might experience in its lifetime, the test rig, to be delivered in 2024, will help improve product reliability and shorten time to market.