The basic principle of permanent magnet motor: The permanent magnet brushless DC motor is composed of a motor body and a driver, and is a typical mechatronic product.
1. The stator winding of the motor is mostly made into a three-phase symmetrical star connection, which is very similar to the three-phase asynchronous motor. A magnetized permanent magnet is attached to the rotor of the motor. In order to detect the polarity of the rotor of the motor, a position sensor is installed in the motor. The driver consists of power electronic devices and integrated circuits.
2. The position sensor coding of the permanent magnet brushless DC motor makes the energized two-phase winding composite magnetic field axis position ahead of the rotor magnetic field axis position, so no matter where the starting position of the rotor is, the motor will generate a large enough force at the moment of starting. Starting torque, so no additional starting winding is required on the rotor.
3. Since the permanent magnet brushless DC motor operates in a self-controlled manner, it will not add a starting winding to the rotor like a synchronous motor with heavy load starting under variable frequency speed regulation, nor will it produce oscillation and loss when the load suddenly changes. step.
As the circuit part of the permanent magnet DC motor, the armature winding plays a vital role in the entire permanent magnet motor. Different classifications meet different voltage and current requirements. The main difference is that they are seen from outside the brush. , the armature windings are connected into different numbers of parallel branches, of which single-stack windings and single-wave windings are the two basic types.
Classification:
(1) Laminated winding: Refers to two components connected in series. The connection method is that the termination part of the latter element is closely stacked on the termination part of the previous element, and the entire winding is folded forward. Laminated windings are further divided into single-stacked and multi-stacked windings. The number of brush sets is equal to the number of poles of the motor. Half of them are positive brush sets and the other half are negative brush sets. The number of parallel branches of the stacked winding is more, which is equal to the number of poles or an integer multiple of the number of poles, so it is also called a parallel winding.
(2) Wave winding: The wave winding of the permanent magnet DC motor refers to the series connection of the corresponding elements under the same polarity magnetic field separated by a pair of pole pitches, like a wave-like advance. Wave windings are further divided into single-wave and complex-wave windings.
(3) Hybrid winding: a kind of DC armature winding formed by mixing properly matched stacked windings and wave windings. The coils of the stack winding and the wave winding are connected to the same commutator and work in parallel. This kind of winding acts as a voltage equalizing line between the wave winding coil and the stacked winding coil, so there is no need to add a voltage equalizing line.
The armature windings of permanent magnet DC motors are divided into three categories according to different connection methods. They each have their own characteristics and advantages, and the conditions of use are also different. When choosing armature windings, you must also choose according to the actual conditions and rated voltage and current to better reflect the excellent performance of the permanent magnet motor.
