DC Motor With Permanent Magnet

In the particular motor can be selected. Current trend is that most new designs are moving towards Brushless DC motors, popularly known as BLDC motors. Like all other motors, BLDC motors also have a rotor and a stator.

Steel laminations in the stator can be slotted or slotless as shown in below pic. A slotless core has lower inductance, thus it can run at very high speeds. Because of the absence of teeth in the lamination stack, requirements for the cogging torque also go down, thus making them an ideal fit for low speeds too (when permanent magnets on rotor and tooth on the stator align with each other then, because of the interaction between the two, an undesirable cogging torque develops and causes ripples in speed). The main disadvantage of a slotless core is higher cost because it requires more winding to compensate for the larger air gap.

China Magnets Source Material Limited produces the permanent magnets on rotor/stator in BLDC motors. View some regular shape as following:

Proper selection of the laminated steel and windings for the construction of stator are crucial to motor performance, the essential component part is the magnet. So how to choose a magnet for your motor, which base on the performance of motor you need. Send your specific magnetic force, working operation environment, drawing to us, china magnets source material will choose proper magnets material solution, offer the best price for you.

The rotor of a typical BLDC motor is made out of permanent magnets. Depending upon the application requirements, the number of poles in the rotor may vary. Increasing the number of poles does give better torque but at the cost of reducing the maximum possible speed.

In below pic 4 (A), the GREEN winding labeled “001” is energized as the NORTH pole and the BLUE winding labeled as “010” is energized as the SOUTH pole. Because of this excitation, the SOUTH pole of the rotor aligns with the GREEN winding and the NORTH pole aligns with the RED winding labeled “100”. In order to move the rotor, the “RED” and “BLUE” windings are energized in the direction shown in below pic 4(B). This causes the RED winding to become the NORTH pole and the BLUE winding to become the SOUTH pole. This shifting of the magnetic field in the stator produces torque because of the development of repulsion (Red winding – NORTH-NORTH alignment) and attraction forces (BLUE winding – NORTH-SOUTH alignment), which moves the rotor in the clockwise direction.