"servomotor" - 1 õppematerjal

Test VIII - cumulative test

If the stator EMF is 100 ant the stator flux is 10, what will be the stator field frequency? 10. What types of motors have the single-sided excitation? the dc excitation? the permanent magnet excitation? the dc supply? the slip rings? the brushless design? The squirrel-cage induction motor has the single-sided excitation. Other motors have both the stator and the rotor excitation. DC excitation is typical for the dc and the synchronous motors. The servomotor and the dc permanent magnet motor are accomplished with permanent magnets, whereas the wound-rotor synchronous and all dc machines have the dc supply. The slip rings transmit supply to the wound rotors of all the ac and dc machines without permanent magnets. The last ones have the brush-less design. Write the formulae of the motor speed. = 12/p = (1 - 2)/p = d/dt, where p is the pole pair number. Particularly, the 2- pole machine has p = 1, not 2 or 4!