Explain how a phase shift between the current in the poles of a motor causes a rotating magnetic field to be created.
This relates to an ac motor, (Alternating Current). The AC current has a sinusoidal wave, of 60 cycles per seconds(USA). Therefore the current is alternating from positive to negative once in each cycle. The coils in the field or armature of the motor, alternately create a magnetic field that alternate synchronously with the current, creating a N(pole) or a (S) pole magnet at the core of the coil. It is this alternating pole (N to S toN to S.....on and on )that creates the attraction or repulsion between the magnetic fields in the housing(stator) and rotor of the motor, causing the rotational movement. A direct current passing thru a coil which is wound around an iron core will produce a magnetic field that makes one end of the iron core as N(pole), the other as(S) pole, steadily. The same set up , but with an alternating current (A.C) will create alternating N pole, and S pole at the same end of the core, changing at the rate of the frequency of the ac supply.
possibly that's greater rather understood with a 2 section device. the availability has 2 voltages ninety stages (no longer one hundred eighty stages) out of section. The motor has 2 pairs of container windings placed opposite one yet another in keeping with section, so the two instruments of poles are ninety stages aside. 4 poles protruding. whilst the availability is expounded, each pole is the choice of the different in its pair, so if there have been in elementary terms one section the magnetic container bridging between the two poles alternates between north to south and south to north. the different pair is ninety stages at the back of (or forward), so the sphere is changed so there's a chain the place the magnetic container is: horizontal left to suitable diagonal decrease left to greater suitable vertical backside to appropriate diagonal decrease suitable to greater left horizontal left to suitable etc.. The link below facilitates to visualise this. the three section case might properly be analysed further, albeit with greater info. the place are there 2 section autos? plenty around, in elementary terms we call them single section autos. the 2nd section is derived from the single section by utilising utilising an inductor or capacitor to produce approximately ninety stages shift for the 2nd section. the sphere rotates as quickly as for each cycle of a particular section in this configuration. In an induction motor the rotor is dragged around by utilising this container. It is going slower than the sphere, so there constantly a difference in rotational velocity. this facilitates the magnetic container interior the rotor to oppose the magnetic container generated by utilising the poles. it is how the present will become proportional to the slip led to by utilising greater load. In a synchronous motor the rotor is a magnet so as that it rotates on the comparable velocity with the aid of fact the sphere.
