There are many features of permanent magnet motors, which I have introduced in detail before. So for the permanent magnet synchronous motor, its operating principle is actually the same as that of the electric excitation synchronous motor, but it replaces the latter's field winding excitation with the magnetic flux supplied by the permanent magnet, making the motor structure simpler. So what are the advantages of permanent magnet synchronous motors? Let’s find out together next!
In recent years, improvements in the performance of permanent magnet materials and advances in electric power technology have promoted the development of new principles and new structure permanent magnet synchronous motors, which have effectively promoted the development of motor product technology, types and functions. Some permanent magnet synchronous motors have Constituting a series of products, its capacity ranges from small to large, and now it has reached the megawatt level, and its scope of use is getting wider and wider; its status is becoming more and more important, from military industry to civilian use, from special to general, it is rapidly expanding, not only in micro and special motors dominant, and also shows strong vitality in the electric propulsion system.
The advantages of permanent magnet synchronous motors are as follows:
1. High power: After the permanent magnet material is embedded in the rotor, the rotor and stator magnetic fields run synchronously during normal operation. There is no induced current in the rotor winding, and there is no rotor resistance and hysteresis loss, thus increasing the motor power.
2. High power factor: There is no induced current excitation in the rotor of the permanent magnet synchronous motor, and the stator winding presents a resistive load. The power factor of the motor is close to 1, which reduces the stator current and increases the power of the motor. At the same time, the improvement of power factor also improves the quality factor of the power grid, reduces the loss of power transmission and transformation lines, and reduces the power transmission and transformation capacity, saving power grid investment.
3. Large starting torque: In equipment that requires large starting torque (such as oil field pumping motors), smaller capacity permanent magnet motors can be used to replace larger capacity Y series motors. If the 37kw permanent magnet synchronous motor replaces the 45kW to 55kW Y series motor, it can better solve the problem of "big horse and small cart", thus saving equipment investment costs and improving the operating efficiency of the system.
4. Good performance indicators: When the Y series motor operates under 60% load, the power drops by 15%, the power factor drops by 30%, and the power target drops by 40%; while the power and power factor of the motor drop very little, when the motor When the load is only 20%, the force target is still more than 80% of the full load.
5. Low temperature rise: There is no resistance loss in the rotor winding, and there is al no reactive current in the stator winding, so the temperature rise of the motor is low.
6. Small size, light weight, and less consumables: The volume, weight, and materials used of a permanent magnet synchronous motor with the same capacity can be reduced by about 30%.
7. It can be made into a large gap to facilitate the formation of new magnetic circuits.
8. The armature has small reaction and strong overload resistance.
In the 21st century, science and technology develop rapidly, high and new technologies continue to emerge, and awareness of power saving and environmental protection is also increasing. The future for the development of permanent magnet synchronous motors is bright, especially high-performance earth motors and their servo systems. With the rapid development of their technology, With the increasing maturity and maturity, the structural types will become increasingly diversified, and they will also gain a wider space for development and become more widely used.
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