Stepper motor dynamic indicators and terms
RELEASE：admin TIME： 2018-08-11 BROWSING： 1171SECOND
1. Step angle accuracy:
The error between the actual value of the stepping motor and the theoretical value of each step angle. It is expressed in percentage: error / step angle *100%. The number of beats in different operation is different. The four beats should be within 5% while the eight beats should be within 15%.
2, out of step:
The number of steps that the motor operates is not equal to the theoretical step. Call it out of step.
3. Misalignment angle:
When the rotor tooth axis deviates from the angle of the stator tooth axis, there must be misalignment angle in the operation of the motor. The error caused by the misalignment angle can not be solved by subdivision drive.
4. Maximum no-load starting frequency:
The maximum frequency at which a motor can start directly without load under a certain driving mode, voltage and rated current.
5. Maximum no-load frequency:
The maximum speed frequency of a motor without load under a certain driving mode, voltage and rated current.
6, running torque frequency characteristics:
The curve of the relationship between the output torque and the frequency is called the operating torque-frequency characteristic, which is the most important dynamic curve of the motor and the fundamental basis for motor selection. As shown in the following figure:
Other characteristics include inertial frequency characteristics, starting frequency characteristics and so on.
Once the motor is selected, the static torque of the motor is determined, but the dynamic torque is not. The dynamic torque of the motor depends on the average current (not static current) when the motor is running. The larger the average current, the greater the output torque, that is, the harder the frequency characteristics of the motor.
As shown in the following figure:
Among them, curve 3 has the largest current or the highest voltage, curve 1 has the smallest current or the lowest voltage, and the point of intersection between curve and load is the maximum speed point of load. In order to make the average current large, as far as possible to increase the driving voltage, so that the use of small inductance large current motor.
7, the resonance point of the motor:
Stepper motors have a fixed resonance region. The resonance region of two-phase and four-phase induction stepper motors is generally between 180-250pps (step angle 1.8 degrees) or around 400 PPS (step angle 0.9 degrees). The higher the driving voltage, the greater the motor current, the lighter the load, the smaller the motor volume, the higher the resonance region, and vice versa. Similarly, in order to make the motor output torque large, not out of step and reduce the noise of the whole system, the general operating point should be offset more resonance region.
8, motor forward and reverse control:
When the power-on sequence of the motor winding is AB-BC-CD-DA or (), it is reversed, while the power-on sequence is DA-CA-BC-AB or ().
The error between the actual value of the stepping motor and the theoretical value of each step angle. It is expressed in percentage: error / step angle *100%. The number of beats in different operation is different. The four beats should be within 5% while the eight beats should be within 15%.
2, out of step:
The number of steps that the motor operates is not equal to the theoretical step. Call it out of step.
3. Misalignment angle:
When the rotor tooth axis deviates from the angle of the stator tooth axis, there must be misalignment angle in the operation of the motor. The error caused by the misalignment angle can not be solved by subdivision drive.
4. Maximum no-load starting frequency:
The maximum frequency at which a motor can start directly without load under a certain driving mode, voltage and rated current.
5. Maximum no-load frequency:
The maximum speed frequency of a motor without load under a certain driving mode, voltage and rated current.
6, running torque frequency characteristics:
The curve of the relationship between the output torque and the frequency is called the operating torque-frequency characteristic, which is the most important dynamic curve of the motor and the fundamental basis for motor selection. As shown in the following figure:
Other characteristics include inertial frequency characteristics, starting frequency characteristics and so on.
Once the motor is selected, the static torque of the motor is determined, but the dynamic torque is not. The dynamic torque of the motor depends on the average current (not static current) when the motor is running. The larger the average current, the greater the output torque, that is, the harder the frequency characteristics of the motor.
As shown in the following figure:
Among them, curve 3 has the largest current or the highest voltage, curve 1 has the smallest current or the lowest voltage, and the point of intersection between curve and load is the maximum speed point of load. In order to make the average current large, as far as possible to increase the driving voltage, so that the use of small inductance large current motor.
7, the resonance point of the motor:
Stepper motors have a fixed resonance region. The resonance region of two-phase and four-phase induction stepper motors is generally between 180-250pps (step angle 1.8 degrees) or around 400 PPS (step angle 0.9 degrees). The higher the driving voltage, the greater the motor current, the lighter the load, the smaller the motor volume, the higher the resonance region, and vice versa. Similarly, in order to make the motor output torque large, not out of step and reduce the noise of the whole system, the general operating point should be offset more resonance region.
8, motor forward and reverse control:
When the power-on sequence of the motor winding is AB-BC-CD-DA or (), it is reversed, while the power-on sequence is DA-CA-BC-AB or ().
