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The working principle of brushless motor

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brushless dc motor is the use of semiconductor switching devices to achieve electronic commutation, that is, with electronic switching devices instead of the traditional contact commutator and brush. It has the advantages of high reliability, no change of spark, low mechanical noise, widely used in high-grade recording blocks, video recorders, electronic equipment and automated office equipment. Brushless DC motor consists of permanent magnet rotor, multi-pole winding stator, position sensor and other components. The position sensor converts the current of the stator winding in a certain order according to the change of the position of the rotor (that is, the position of the rotor pole relative to the stator winding is detected and the position sensing signal is generated at the determined position and processed by the signal conversion circuit To control the power switch circuit, according to a certain logical relationship between the winding current switching). The operatin
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Control principle of DC brushless motor

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dc brushless motor control principle, let the motor turn up, first control department must be based on hall-sensor sensor to the motor rotor position, and then in accordance with the stator winding to open (or close) converter (inverter) in the power (Hereinafter referred to as the upper arm power transistor) and AL, BL, CL (these are called lower arm power transistors). so that the current flow through the motor coil to produce forward (or reverse ) Rotate the magnetic field and interact with the magnet of the rotor, so that the motor can be rotated in time / reverse. When the motor rotor rotates to the position where the hall-sensor senses the other set of signals, the control section turns on the next set of power transistors again so that the cycle motor can continue to rotate in the same direction until the control section decides to turn off the motor when the motor is stopped Transistor (or only the lower arm power transistor); to the brushless dc motor rotor reverse t
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The definition of DC motor

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Definition: energy ( DC motor ) or converts the mechanical energy into direct current electricity (DC generator) for rotating electrical machines. It is a DC motor of electric energy and mechanical energy conversion. Electric runtime when it is DC motor convert electrical energy into mechanical energy; for generating runtime is a DC generator, converts mechanical energy to electrical energy. Advantages and disadvantages: advantages: brushless dc motor with fast response, large starting torque, rotational speed from zero to the rated rotary speed with rated torque performance can provide. Disadvantage: because DC motors to produce the rated load constant torque performance of armature and rotor magnetic field required constant maintenance of 90°, this will be through the carbon brush and commutator. Carbon brush and commutator motor will produce sparks, toner so the outside will cause damage to the components, use is restricted.
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The working principles of DC motor

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DC motor inside the fixed ring permanent magnet, the current through the coil on the rotor to produce ampere force, when the rotor on the rotor and the magnetic field parallel, and then continue to turn the direction of the magnetic field will change, so the rotor at the end of the brush with the conversion The sheet is alternately contacted so that the direction of the current on the coil also changes, resulting in the direction of the Lorentz force unchanged, so the motor can maintain a direction of rotation. The working principle of the DC generator is to interpolate the armature coil in the alternating electromotive force, By the commutator with the brush of the commutation effect, so that when the brush from the brush leads to the principle of DC electromotive force. The direction of the induced electromotive force is determined by the right hand rule (the magnetic induction line points to the palm of the hand, the thumb is pointing to the direction of the conductor movement,
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