The IDIM (Inverse Dynamic Identification Models) method is based on a closed loop identification of the inverse model which is linear in relation to the parameters. By mixing the OE (Output Error) method and the IDIM technique, we obtain the method called DIDIM (Direct and Inverse Dynamic Identification Models). Experimental results on decoupled identification of the electrical dynamic and the mechanical dynamic have proven the efficiency of the IDIM and the DIDIM methods. But to perform a global identification of all the parameters, whatever the electrical machines (direct current motor, synchronous motor, asynchronous motor), it has been necessary to introduce two phases of calculations to get the parameters. This is why we have called them IDIM2 and DIDIM2. In this paper, we have presented the comparison of these four methods with experimentations on a DC motor, which has simple equations, to see easily nuances between IDIM, DIDIM, IDIM2, DIDIM2.