What is the regulation method of ac motor? What are the different features
Frequency changer: stable, adjustable speed according to need, which is the development direction of future ac motor. (FM) 2, star, delta transform, generally in large motor start with star, triangle operation, reduce the starting current. In addition, it is a two-speed, three-speed motor, which increases the winding, which mainly changes the order of the stator winding to change the speed. The change in rotational speed has two factors: the magnetic poles and the frequencies
Friend, one, change the logarithmic speed control method: change the red way of the stator winding to change the stator pole of the cage motor to achieve the speed adjustment. Two, frequency control method: changing the frequency of the motor stator power by using the frequency converter, changing the speed control method of the synchronous speed. Three, cascade speed regulation method: cascade speed regulation refers to the wound rotor motor rotor loop series adjustable the additional potential to change the slip of the motor, to achieve the purpose of speed control. Most of the slip power is absorbed by series of additional potential to recycle produce additional device, the absorption of returning the slip power grid or conversion of energy use. According to the slip power utilization way, cascade speed regulation can be divided into motor cascade speed regulation, mechanical cascade speed regulation and thyristor cascade speed regulation form, adopts thyristor cascade speed regulation. Four, wound rotor motor rotor series resistance speed control methods: line type asynchronous motor rotor string into the additional resistance, make the slip of the motor, motor under low speed running.
Regulating speed, speed range is limited speed regulating pole change motor is rarely used, internal connection mode change motor speed, speed is a great speed according to the setting of motor factory brand speed regulation of frequency conversion speed adjustment, change the motor input frequency speed regulation, belong to the infinite speed adjustment is popular now
The larger the resistance, the lower the speed of the motor. This method is simple and easy to control, but the switching power is used in the form of heating. It is a kind of speed adjustment, and the mechanical properties are softer. Control method: change the stator voltage of the motor to achieve different speeds. Because the torque of the motor is proportional to the square of the voltage, the maximum torque decreases a lot, and its speed limit is small, which makes the general cage motor difficult to apply. In order to extend the range of speed adjustment, the speed adjustment speed adjustment should adopt the cage motor with large rotor resistance value,
