- In DC motor and armature rotate inside the magnetic field, basic working principle of a DC motor based on the fact whenever a current- carrying conductor placed inside a magnetic field there will be a mechanical force experienced by the conductor. A PMDC motor consists of two main parts rotor or ammeter and stator.
- Hence construction for DC motor it is essential to establish a magnetic fields magnet can be any type electromagnet or permanent magnet is using to create magnetic field in a DC motor the motor is refer as permanent magnet DC motor or PMDC motor.
- Here stator permanent magnet permanent magnet mounted in the inner periphery of stator frame permanent magnet mounted in such a way that N pole and S pole of each magnet is alternately faced to each other rotor of permanent magnet motor is similar to other DC motor. The rotor consists of core, winding and commutation, armature core is made of number of vanish insulated, slotted circular lamination.
- By placing this circular steel one-by-one armature core has formed, the armature conductor has connected to the rotor as star connection and the other terminal of winding has connected to the commutator segments, placed on the motor shaft carbon or graphite brushes has placed with spring pressure on the commutator segment to supply current to the armature when supply was given current passes through one commutator segment AB BC or CA.
- Suppose that current passes through CA path then coil A behave like a North Pole and C as South Pole. Then a torque work on rotor because “A” experience a repulsion force due to this south pole of permanent magnet and “C” experience and attraction force due to north pole of permanent magnet and due to this torque the rotor will rotate.
- The advantage of permanent magnet DC motor no input power is consume for it field excitation which is improve the DC motor efficiency. If we use tow pole in the rotor, the magnetic lock-down will work, on torque will work this rotor, to increase the power of motor. We can increase number of pole.
