RotationalDynamicsRHS:

--------------------------------------------------------------------------
   Rotational dynamics model.
   The angular acceleration is the difference between the electromagnetic
   torque and the wind (or mechanical) torque.
--------------------------------------------------------------------------
   Form:
   omegaDot = RotationalDynamicsRHS( omega, t, d )
--------------------------------------------------------------------------

   ------
   Inputs
   ------
   omega         (1,1)       Angular rate
   t             (1,1)       Time (not used)
   d             (1,1)       Data structure
                             .h             (1,1) Forward gain (sec)
                             .tEM           (1,1) Back emf torque (Nm)
                             .tW            (1,1) Wind torque (Nm)

   -------
   Outputs
   -------
   omegaDot      (1,1)       Angular accelerations

--------------------------------------------------------------------------
   Reference: Gill Estevez, P. ,"Model Dinamico de Una Turbina 
              de velocidad variable con Generador de Imanes Permanentes y 
              control de angulo de calaje ? Analisis de Control de 
              Velocidad. Figure 5.
--------------------------------------------------------------------------