Permanent magnet stepper motor permanent magnet servo motor are permanent magnet synchronous motors, their common feature is that they have a permanent magnet field can be operated without external magnetic field excitation. However, there are some differences between the two kinds of motors in application scenario, control mode, accuracy so on.
1. Application Scenarioses
Permanent magnet stepper motors are suitable for low-speed, high-torque rotary applications, such as injection machines, printing presses, cable machines other industries. It moves at a constant speed according to the given pulse isocline straight line, the number of running steps is fixed, the precision torque deviation is small, the stability is high.
The permanent magnet servo motor is suitable for medium high speed, high precision rotation applications, such as CNC machine tools, robots, electronic equipment so on. Its movement is in accordance with the given position, speed, acceleration other curve movement, can achieve high precision positioning, high speed tracking accuracy, fast response speed, good dynamic performance.
2. Control mode
The permanent magnet stepper motor adopts the open-loop control mode, changes the position of the motor rotor by controlling the pulse signal, controls the number direction of its rotation steps. In many application scenarioses, only simple signal control can achieve high rotation accuracy, almost no feedback control is required, the cost is low.
The permanent magnet servo motor adopts a closed-loop control mode, needs to install a feedback system such as encoder. The feedback controller can control the target position, speed, acceleration, etc., which can achieve very high-precision control with high precision but large cost.
3. Accuracy
The permanent magnet stepper motor can usually achieve angular accuracy of 1.8 degrees position accuracy of 0.024mm. The Angle accuracy of permanent magnet servo motor can usually reach 0.001 degrees, the position accuracy can reach 0.0001mm. Therefore, permanent magnet servo motors are usually used in application scenarioses high precision is required.
Fourth, adaptability stability
Permanent magnet stepper motor has better adaptability stability, suitable for a variety of different types of drivers controllers, does appear out of step phenomenon, has a strong driving torque anti-interference ability, but the movement speed is relatively slow, complex precise movement requires multi-step movement to achieve.
The permanent magnet servo motor needs to be used with a professional servo controller to play the performance, need the mechanical, control system other aspects to achieve excellent performance, while high stability, fast response speed, can adapt to high-speed complex motion state.
Conclusion:
In summary, there are some differences between permanent magnet stepper motor permanent magnet servo motor in application scenarioses, control methods, accuracy, adaptability stability. In the selection should be based on actual needs to determine the specific use of motor. If you need low-cost, precision requirements are high application, you can choose permanent magnet stepper motor; If you need high precision, high speed, complex motion state control, it is recommended to use permanent magnet servo motor.