What is the structure of servo motor and stepper motor 10

The structure of AC servo motor can be mainly divided into two parts, namely the stator part and the rotor part. The structure of the stator is basically the same as that of the resolver, and a two-phase winding with an electric angle of 90 degrees is also placed in the center of the stator. One of them is the excitation winding, the other is the control winding, and the AC servo motor is a two-phase AC motor.

Working principle: The rotor inside the servo motor is a permanent magnet, and the U V W three-phase electricity controlled by the driver forms an electromagnetic field, and the rotor rotates under the action of this magnetic field, and at the same time, the encoder of the motor feeds back the signal to the driver, and the driver compares the feedback value with the target value to adjust the angle of rotation of the rotor. The accuracy of the servo motor is determined by the accuracy of the encoder (number of lines).

The stepper motor is driven by a set of coils wound around the stator cogging, a fixed part of the motor. Normally, a wire wound in a loop is called a solenoid.

Working principle: A stepper motor is an open-loop control element that converts an electrical pulse signal into angular displacement or linear displacement. In the case of non-overload, the speed of the motor and the position of the stop only depend on the frequency and number of pulses of the pulse signal, and are not affected by the change of load, that is, a pulse signal is added to the motor, and the motor turns a step angle.

The existence of this linear relationship, coupled with the fact that the stepper motor has only periodic errors and no cumulative errors. It makes it very easy to control with stepper motors in the field of speed, position and other control fields.

The stepper motor is open-loop, and the servo motor is semi-closed-loop.

Their accuracy levels are different, and you can understand the difference between the two types of motors.

According to the mechanical process, motion accuracy requirements, etc., there are many overlapping applications in the general occasion, but in the occasion of low speed and high precision, the former has obvious advantages, and the latter has obvious advantages in high speed and high precision.

The difference between stepper motor Sakuraeda Zhenghe servo motor:

The way of control is different:The stepper motor controls the rotation angle by controlling the number of pulses, and the servo motor controls the rotation angle by controlling the length of the pulse time.

The workflow is different:The stepper motor needs two pulses to work, and the servo motor is the power connection switch; The characteristics of low tie positive frequency are different: the stepper motor is prone to low-frequency vibration at low speed, and the servo motor runs very smoothly.

1. Different control methods: the stepper motor controls the rotation angle by controlling the number of pulses, and the servo motor controls the rotation angle by controlling the length of the pulse time; 2. The process is different: the stepper motor generally needs two pulses to work, and the servo motor is a power supply connection switch, and then connected to the servo motor; 3. Different characteristics:

The stepper motor is prone to low-frequency vibration at low speed, while the servo motor runs very smoothly; 4. The speed is different: the maximum working speed of the stepper motor is 300 600r min, and the rated speed of the servo motor is 2000 or 3000r min.

Stepper motors. The stepper motor, also known as the pulse motor, is based on the most basic electromagnetic principle of electromagnetism, which is an electromagnet that can rotate freely, and its action principle is to rely on the change of air gap magnetic conductance to generate electromagnetic torque. Stool limb yard.

There are many structural forms and classification methods of stepper motors, which are generally divided into three types: reluctance, permanent magnet and mixed magnet according to the excitation mode; According to the number of phases, it can be divided into single-phase, two-phase, three-phase and multi-phase forms.

Among the stepper motors used in China, the reactive stepper motor is the main one. The operation performance of the stepper motor is closely related to the control mode, and the stepper motor control system can be divided into the following three categories from the perspective of its control mode: open-loop control hunger cultivation system, closed-loop control system, and semi-closed-loop control system.

Semi-closed-loop control systems are generally classified as open-loop or closed-loop systems in practical applications.

1. Stepper motor.

Advantages: 1. The angle of rotation of the motor is proportional to the number of pulses;

2. The motor has the maximum torque when it stops (when the winding is excited);

3. Because the accuracy of each step is between three and five percent, and the error of one step will not accumulate to the next step, it has better position accuracy and repeatability of movement;

4. Excellent start-stop and reversal response;

5. Because there is no brush, the reliability is high, so the life of the motor only depends on the life of the bearing;

6. The response of the motor is only determined by the digital input pulse, so it can be controlled by open loop, which makes the structure of the motor relatively simple and the cost can be controlled;

7. Synchronous rotation at very low speed can also be achieved by simply connecting the load directly to the shaft of the motor;

8. Because the speed is proportional to the pulse frequency, it has a relatively wide speed range.

Defects: 1. If the control is improper, it is easy to resonate;

2. It is difficult to run to a higher speed;

3. It is difficult to obtain a large torque;

4. There is no advantage in volume and weight, and the energy utilization rate is low;

5. When the load is exceeded, the synchronization will be destroyed, and the vibration and noise will be emitted when working at high speed.

2. Servo motor.

Advantages: 1. There are no brushes and commutators, so the work is reliable, and the requirements for maintenance and maintenance are low.

2. The heat dissipation of the stator winding is more convenient.

3. The inertia is small, which is easy to improve the rapidity of the system.

4. It is suitable for high-speed and high-torque working with collapse state.

Disadvantages: 1. The servo must be adjusted according to the needs of the load;

2. There will be powder with worn brushes, which cannot be used in a clean environment;

3. The brushes will be consumed and need to be maintained;

4. It will produce mechanical and motor noise.

1. The control accuracy is different: the pulse equivalent of the AC servo motor is a few hundredths of the pulse equivalent of the stepper motor.

2. Different low-frequency characteristics: stepper motors are prone to low-frequency vibration at low speeds.

The AC servo motor runs very smoothly and does not vibrate even at low speeds.

3. The characteristics of the torque frequency are different: the output torque of the stepper motor decreases with the increase of speed, and will drop sharply at higher speed, so its maximum working speed is generally 300 to 600rpm. The AC servo motor is a constant torque output, that is, within its rated speed of 2000rpm or 3000rpm, the socks can output the rated torque, and the rated speed is above the constant power output.

4. Different overload capacity: stepper motors generally do not have overload capacity. The AC servo motor has a strong overload capacity.

5. Different running performance: the control of the stepper motor is open-loop control, which is prone to the phenomenon of losing steps or overshooting. The AC servo drive system is closed-loop control, and there is generally no loss of step or overshoot of the stepper motor.

6. The speed response performance is different: it takes hundreds of milliseconds for the stepper motor to accelerate from a standstill to the working speed. The acceleration performance of the AC servo system is good, and it only takes a few milliseconds to accelerate from a standstill to its rated speed.

Dear, hello, I am happy to answer your questions, the working principle of the stepper servo motor is as follows: the rotor inside the servo nuclear service motor is a permanent magnet, and the U V W three-phase electricity controlled by the driver forms an electromagnetic field, and the rotor rotates under the action of this magnetic field, and at the same time, the encoder feedback signal of the motor spontaneous combustion vertical digging belt is given to the driver, and the driving fiber is compared with the target value to adjust the angle of rotation of the rotor according to the feedback value. The accuracy of the servo motor is determined by the accuracy of the encoder (number of lines).

I hope my answers help you and I wish you a happy life.