Page 89 - Robotics Designing the Mechanisms for Automated Machinery

78 Dynamic Analysis of Drives

FIGURE 3.l4b) Rotation speed of the system driven by a synchronous motor.

For synchronous induction motors, the characteristic is a straight line for a certain
range of torques, as is shown in Figure 3.15. After the maximal value T m of the torque
is reached, the motor stops and is not able to work. This maximal torque occurs when
the angle 0 between the vector of the rotating flux of the stator and the geometric axis
of the rotor's poles equals O m which is about half of the angular pitch of the poles. The
dependence T d (ff) is very important in the theory of synchronous inductive motors
and usually has the form shown in Figure 3.16.

FIGURE 3.15 Torque versus the constant rotation
speed of a synchronous induction motor.

FIGURE 3.16 Characteristic of a synchronous induction
motor: torque versus the angle between the rotating
flux and the geometric axis of the rotor's poles.