**6. Conclusion**

272 Induction Motors – Modelling and Control

effects during rotor axial motion. This is the only influence of linear part of TARLIM on rotary motion and, as stated earlier, both armatures have no more influence on one another due to the relatively long distance and the lack of magnetic interaction in between. To determine the influence of rotor axial motion on the performance of rotary armature, the characteristics of electromagnetic torque (Tem) and mechanical power (Pm) versus rotary slip at three different linear speeds (u = 0 m/s, u =3 m/s and u =6 m/s) along with experimental results at zero linear speed (u = 0 m/s) are plotted in Figs. 30 and 31. These effects contribute to diminishing of torque and all other rotary motor performances. One can observe that, the

higher axial speed leads to lower rotary torque and mechanical power.

**Figure 30.** Characteristic of Torque vs rotary slip with and without linear motion.

**Figure 31.** Characteristic of output power vs linear slip with and without linear motion.

Note, that the output quantities are extremely dependent on the property of materials. The conductivity of the materials used in 3D FEM analysis is kept constant, but in reality it might be influenced by the temperature. Therefore, minimal mismatch between Rotary-linear induction motor is one of a few types of motors with two degrees of mechanical freedom. It may find application in robotics and special types of drives like machine tools and drilling machines. One of its representatives, the TARLIM, with two solid layer rotor was modelled in 3-D FEMM and its performance has been determined. The operation of the motor does not differ from the operation of machine set consisting rotary and tubular linear motor of which rotors are firmly coupled. The electromechanical performances of the motor are affected by the end effects which are familiar phenomena in linear machines. Practically, the impact of these phenomena is not significant in low axial speed of the rotor, what is expected for these types of motors.

The results obtained from the test carried out on the experimental model do not differ much from the ones got from simulations. Thus they validate the theoretical modeling of the motor.

Motor with the rotor cage made in form of grid placed on the cylindrical core is another version of TARLIM and is expected to have a better performance with respect to the solid two layer rotor.
