Classification and application of permanent magnet brushless DC motor

<p> A stator of the brushless DC motor is provided with fixing the main pole and the brush,the rotor is installed on the armature winding and commutator. DC power supply ofelectrical energy into the armature winding through the brush and commutator,produce the armature current, armature current generates a magnetic field and the main magnetic field produced in the interaction of electromagnetic torque, the motor rotates to drive the load. Because of the existence of the brushes and commutator,brush motor complex structure, poor reliability, fault, maintenance workload, short service life, easy to produce electromagnetic interference commutation spark. </p> <p> A magnet on the fixed part of brush DC motor, here known as the main pole; a fixed part and a brush. The rotating part has an annular iron core and winding is wound onan annular iron core. </p> <p> There is a fixed part of the brush DC motor (stator) is provided with a main pole N a pair of DC excitation of stationary and S, the rotating part (the rotor) is provided withan armature core. There is an air gap between the stator and the rotor. In the armature core placed on the armature coil are connected by the A and X of twoconductors, and at the end of the first coil are respectively connected to the two arc of the copper, the copper called commutator. Reversing pieces are mutually insulated,constituted by the commutator is called a commutator. Commutator is fixed on the rotating shaft, the rotating shaft between the commutator and are insulated from each other. The commutator is placed on a pair of fixed brush B1 and B2, when the armature rotates, the armature coil through the commutator and brush and connected to external circuit. </p> <p> With the development of the times, application of permanent magnetic DC motor will be more, the original with many occasions of AC motor is a permanent magnet DC motor replaced. Especially the emergence of permanent magnet brushless motor,permanent magnetic DC motor production quantity in the rising. The great annualproduction of our country of permanent magnetic DC motor billions of above, the production of permanent magnetic DC motor manufacturers too many to count. </p> <p> Permanent magnet DC motor is a DC motor with permanent magnet magnetic field is established. Permanent magnet DC motor is widely used in various portable electronicequipment or apparatus, such as a tape recorder, VCD player, phonograph, electric massager and various kinds of toys, but also widely used in automobile, motorcycle,electric bicycle, battery car, ship, aviation, machinery and other industries, is widely used in sophisticated products, such as video, photocopiers, cameras, mobile phone,precision machine tools, bank currency-counting machine, banknote bundlingmachine. In stage lighting, permanent magnetic DC motor, especially the small permanent magnet dc gear motor use very large. In the computer industry printer,scanner, hard drives, CD-ROM drives, recorder, cooling fans and are used in a large number of permanent magnetic DC motor. </p> <p> In industry, agriculture, permanent magnet DC motor is widely used in electrical andautomation control and instrumentation. In medical terms, permanent magnet DC motor use more, such as a variety of instruments, medical operation tools, such asbrain operation in electric bone saw blade, especially all kinds of instruments in thefield operation basically is a permanent magnet DC motor with. In the disabledactivities, such as robots, disability and other vehicles are used in permanent magnet DC motor. More useful in life, and even a toothbrush also used permanent magnet DC motor made electric toothbrush. </p> <p> The automotive industry in various fan, wiper, water pump, extinguisher, rearview mirror, pump is used in a variety of permanent magnetic DC motor. Hotels in theautomatic door, automatic door locks, automatic curtain, automatic water supply system, soft towel machine are used in permanent magnet DC motor, the weapons and equipment, permanent magnet DC motor is widely used in missiles, artillery,satellites, spacecraft, ships, aircraft, tanks, rocket, radar, tanks and other occasions. </p> <p> Application of permanent magnetic DC motor is numerous, can be said to be everywhere. </p> <p> Permanent magnetic motor type mainly has following several: </p> <p> 1 brush printed winding motor. Brush a printed winding motor with printed foil plate as winding, motor weight. Because of this motor are all in the production of automaticproduction line, process to ensure a reliable, so that the service life of the motor is increased to 3000h, the noise is greatly reduced and the efficiency is increased to 72% ~ 76%. But this kind of motor has "high frequency noise buzz", by the gear reduction efficiency is still not ideal, use brush commutation device so that the service life of the motor can not increase. </p> <p> 2 brush suppression winding motor. The motor winding wire by pressing into a new type of winding, the efficiency can be increased to 74% ~ 78%. The motor is still moreelectric bicycle manufacturers to adopt, but the existence of the efficiency, noise, lifeis still the problem of defects must be improved. </p> <p> 3 brush disc winding motor. A brush disc winding motor with rare earth materials bonded on a cylinder, placed within the disc winding enamelled copper wire is wound into a cylinder, a rotor. The motor phase by mechanical commutation regulator.Mechanical commutation device is fixed on the carbon brush and the rotating of copper change physiognomy friction to adjust the voltage phase. This machine has been in use in the brush wear, the service life of the motor is less than the 2000h. At the same time, because of the speed of the motor is high, must take the two gear reducer, this leads to two problems, one is the large noise, two is the loss of efficiency, the efficiency of the motor rated after deceleration often can only reach 68% ~ 72%. Battery for electric bicycle capacity is limited, the general is the capacity of 36V/12Ah, such as the motor efficiency is not high, will the power consumption is increased, effect of mileage. </p>