Advantages and disadvantages of stepper motor and servo motor


Advantages of servo motors compared to stepper motors F […]

Advantages of servo motors compared to stepper motors

First, the low frequency characteristics

When the stepping motor runs at low speed, low-frequency vibration occurs, and the smooth running of the motor is slightly inferior to that of the servo motor.

The AC servo motor runs very smoothly, and vibration does not occur even at low speeds.

Second, the frequency characteristics

The output torque of the stepping motor will decrease with the increase of the speed, and will drop sharply at higher speeds. The stepping motor will have a small torque at high speed.

The AC servo motor is a constant torque output, which can maintain the torque at its rated speed and can output the rated torque.

Third, control accuracy

The control of the stepping motor is open-loop control. If the starting frequency is too high or the load is too large, it may be lost or blocked. When the speed is too high, the overshoot may occur, so to ensure the control accuracy, when selecting the type The output of the motor must have sufficient margin, and the problem of starting and slowing down should be handled.

The servo motor drive system is closed-loop control. The driver can directly sample the motor encoder feedback signal. The motor and the driver form a closed-loop control. The stepping motor does not lose the step condition in its rated torque. Come back, the control accuracy is more reliable.

Advantages of stepper motor compared to servo motor

First, the operating performance

The stepping motor running tracking performance is better than the servo motor. Since the stepping motor sends an angle every time a pulse is sent, the motor will go without a delay, and the servo motor is closed-loop controlled, and the pulse and code return are sent. Contrast processing, if there is overshoot in the turn back, there is a certain delay, the trace characteristics are worse than the stepper motor. For example, draw a circle with an engraving machine, and the servo motor is not painted by a stepper motor. Stepper motors must be used where frequent forward and reverse tracking characteristics are required.

Second, the operation settings

The stepper motor drive setting is simple, just set the current and subdivide it.

The servo drive has hundreds of parameter settings, and the setting is very cumbersome.

Third, the motor

The same torque motor stepper motor is much smaller than the servo motor, such as 6NM motor, stepper motor 86 can be made, and the servo motor should be 110 or more.

Stepper motor price is much lower than servo motor

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