A sensorless brushless motor and its anti-stall control method

Abstract

The invention relates to a non-inductive brushless motor, which comprises a rotor and a stator, and is characterized by further comprising a Hall sensor for rotation-clogging prevention detection, wherein the Hall sensor is arranged on the stator. A rotation-clogging prevention control method of the non-inductive brushless motor is further disclosed. Compared with the prior art, the non-inductivebrushless motor and the rotation-clogging prevention control method thereof have the advantages that: the Hall sensor is arranged on the stator of the non-inductive brushless motor, output signals ofa power supply module and the Hall sensor that can make the motor change are found when the non-inductive brushless motor encounters rotation clogging, and a region where the rotor is positioned is determined according to the output signals, thereby the optimal power supply mode is selected, such that the motor gets rid of the rotation-clogging state, the non-inductive brushless motor is simple instructure, can effectively solve the rotation-clogging situation of the motor when the load is too heavy, and drives the motor to enter into a normal operating condition.

Description

technical field [0001] The invention relates to the field of motors, in particular to a non-sensing brushless motor and an anti-stall control method thereof. Background technique [0002] With the development of modern technology, brushless motors are widely used in daily life appliances, automotive industry, aviation, consumer electronics, medical electronics, industrial automation and other devices and instruments. Brushless motors are mainly composed of rotors made of permanent magnet materials, The stator with coil winding is composed of a brushless motor. Unlike a brush motor, a brushless motor does not use a mechanical commutation brush but directly uses an electronic commutator for commutation. To make the brushless motor rotate, it must be in accordance with The stator is energized in a certain order, then we need to know the position of the rotor in order to energize the corresponding stator coils according to the order of energization. The brushless motor is divide...

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Problems solved by technology

[0003] Among them, such as figure 1 As shown, there are three Hall sensors 1 installed in the sensored brushless motor. The direction of the magnetic field is sensed by the Hall sensors, and output high and low levels. According to the output value of the Hall sensors, the position of the rotor 2 can be accurately determined, and passed Accurately control the power supply mode of the motor to achieve the function of starting the motor. Therefore, the Hall sensor of the sensory brushless motor is used to detect the position of the rotor. When the sensory brushless motor is locked, it can only be driven by increasing the current The motor rotates, but when the applied current is too large, it is easy to damage the motor, and due to the complex structure and high cost of the sensory brushless motor itself, a non-sensing brushless motor is often used in practical applications. Without Hall sensor, the detection of the starting position of the non-inductive brushless motor is obtained by detecting the counter electromotive force of the motor coil. Large requirements, the back electromotive force can only be detected after reaching at least 10% of the rated speed. Therefore, when the non-inductive brushless motor is blocked, the motor can only shake and cannot rotate. In this case, the commonly used motor cannot be used. Blind start to start the motor, and the high-frequency signal injection method has higher requirements on the motor and control chip, and the cost is higher

[0004] The stalling of the non-inductive brushless motor does not mean that the external force is far greater than the working torque of the motor itself, but a relative situation. It is within the range of the motor's working capacity, but the motor cannot reach a certain normal speed because of the lack of rotation speed when starting. It is impossible to correctly judge the electrical angle by measuring the back electromotive force to realize commutation

In fact, this should be regarded as starting with load, but the load is a bit too large, so that the brushless motor cannot quickly increase the speed and enter the normal operation state. At this time, the motor is only moving but rotating abnormally, so further solutions are needed. Stall problem of brushless motor

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