Dynamic Balancing is the process for testing a wind turbine’s rotor to quantify the residual unbalance.
…unlike many think Dynamic Balancing is not a made-up process!
…or free for individual interpretations?
Equation of motion for the system “wind turbine” a driven harmonic oscillator
ISO 1940-1 “how to measure” requirement:
“…by means of a device capable of measuring amplitude and phase of the once-per-revolution vibration.”(RMS values are invalid)
We have refined dynamic balancing as an application for a commercial-size wind turbine for almost two decades. We have overcome the challenges posed by the undoubted aerodynamic component early in the process of providing the service. There is no doubt that a wind turbine’s blade is for the purpose of balancing NOT just a beam structure.
Any vibration measured at the rotor’s speed is effectively an integral unbalance vector comprised of the actual mass unbalance vector in any possible vector combination of the aerodynamic unbalance vector.
You can not ignore the aerodynamic part you have to address and remove it!
But not to worry we developed a method covering this part very successfully.
While most structures are meant to withstand linear axial and lateral vibration which can be caused by a strict mass unbalance, any aerodynamic unbalance will cause torsional vibration.
In some extreme cases, we even have observed an orbital motion relative to the tower's center or combined structural center of gravity.
Those torsional (tower twisting) motions appear to be the most destructive ones!