The authors introduce the model of a planetary gear using EMR and Matlab-SimDriveline.

The paper clarity should be improved in some points:

- The authors should explain under which hypothesis Equations (3) and (4) are deduced

- It is not clear what Equation (4) stands for as the equivalent inertia in the accumulation element of Fig.3
  is 2-dimensional 

- The global EMR of the considered system in Fig.3 considers Tem4 as output of the first mechanical coupling element. 
  This seems to be in contrast with Equation (2). In fact from Equation (2) one can find 
  Ta1= n TemA and  Ta2= (1-n)TemA
  
- Equation (2) is not correct in the sign of n

