First, the control accuracy is different;
The servo motor control accuracy is guaranteed by the rotary encoder at the rear end of the motor shaft, and the control accuracy of servo motor is higher than stepper motor.
Second, the low frequency characteristics are different;
The servo motor runs very smoothly, and It doesn't vibrate even though at low speed. Generally, the low-frequency performance of the servo motor is better than stepper motor.
Third, the overload capacity is different;
Stepper motor doesn't has overload capability, servo motor has strong overload capability.
Fourth, different operating performance;
The control of the stepper motor is open loop control, and the AC servo drive system is closed loop control.
Fifth, the speed response performance is different;
AC servo system has better acceleration performance.