Whether the mainstream of permanent magnet synchronous motor is the future trend
Is the permanent magnet synchronous motor mainstream, is it a future trend?
It is understood that the application of permanent magnet synchronous motors is increasing, the voltage level is continuously improved, and the rotational speed is also getting higher and higher. According to statistics, in the first batch of recommended catalogues in 2017, 150 models were equipped with permanent magnet synchronous motors, accounting for 81%; 33 models with AC asynchronous motors accounted for 18%; unknown 2 models.
It can be seen that most models choose permanent magnet synchronous motors. Although Tesla uses asynchronous motors, the industry believes that mainly due to cost factors and actual average efficiency factors, it is reported that Tesla Model3 will use permanent magnet synchronous motors. It can be said that permanent magnet synchronous motor will be the trend of the times! According to information collection, currently well-known foreign car companies, such as BMW's ActiveHybrid and i3, Toyota PruisIV and Leaf, Tesla Model3, Honda CivicHybrid, Chevrolet Volt, etc., use permanent magnet synchronous motors.
The advantages of the switched reluctance motor are obvious. The structure and control of the switched reluctance motor are simple, the output is large, the reliability is high, the cost is low, the starting braking performance is good, and the running efficiency is high. But why is it not widely used in electric vehicles? The main factors are: 1. The cost caused by the pulsating factor increases; 2. The pulsating torque causes noise; 3. The nonlinearity is serious. 4. It is constantly being explored and developed.
The permanent magnet synchronous motor has high power density, high reliability, high power factor, high speed range, good speed control performance and wide speed range. The permanent magnet synchronous motor has no excitation loss and heat dissipation problem. The motor has a simple structure and is 15% smaller than the asynchronous motor of the same power.
The advantages of permanent magnet synchronous motor compared with AC asynchronous motor are: (1) high efficiency and more power saving; (2) high power factor; (3) simple and flexible motor structure; (4) high reliability; (5) small size , high power density; (6) large starting torque, low noise, low temperature rise.
However, the permanent magnet synchronous motor also has its disadvantages. Compared with the DC motor, it does not have the commutator and the brush of the DC motor, and requires more maintenance, which brings inconvenience to the application. Compared with the asynchronous motor, the permanent magnet synchronous motor is relatively simple, the stator current and the stator resistance loss are reduced, and the rotor parameters can be measured and the control performance is good, but the maximum torque is limited by the demagnetization of the permanent magnet, and the seismic resistance is poor. The high speed is limited, the power is small, the cost is high, and the starting is difficult.