Rotordynamic Analysis for Machines with Active Magnetic Bearings

Using the unique Matlab/Dyrobes toolset (more...), Xdot has generated a very general active magnetic bearing analysis capability. By leveraging the tools we use for day-to-day consulting work, this toolset gives us all of the capabilities of a research code, but with the efficiency of a consulting tool.

A rotor model gets built in Dyrobes as usual. Then the model's system matrices are exported to Matlab. In Matlab, this rotor model gets augmented with the AMB system dynamics (sensors, control system, amplifiers, actuators). A variety of analyses can then be performed. Since Matlab is being used, nearly any AMB system description (state-space, transfer function, etc.) can be used. The data structures are also reasonably compatible with Matlab's control system toolbox if more advanced analysis is required. All of our standard analysis and post-processing functions available, along with a few specialized ones just for AMB analysis. The capabilities include:

  • Eigenvalue (whirl speed/stability/modeshapes) analysis
  • Parametric stability (effect of added cross-coupling) analysis
  • Steady-state (unbalance) response
  • Open-loop transfer functions
  • Closed-loop transfer functions
  • Sensitivity functions
  • Parametric analysis for nearly any parameter

Dynamic Force Limit Ratio

Sensitivity Function

Parametric Sensitivity Function Analysis for Added Cross Coupling

Open Loop Transfer Function

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