Stepper motor driver Principle（步进电机驱动器原理）
1, the stepper motor is a special motor as control, it is the rotation of the fixed point (called "step") operation step by step, which is characterized by no accumulated error (accuracy of 100%), so it is widely used in a variety of open-loop control. Stepper motor operation to have an electronic device driver, this device is the stepper motor drive control system, it is a pulse signal into angular displacement, the stepper motor or the control system: each made of a pulse signal, the driver makes a step angle stepper motor rotation. Therefore, the speed of the stepper motor is proportional to the frequency of the pulse signal. Therefore, to control the frequency of the stepped pulse signal, the motor can be adjusted accurately. The number of step pulses can be controlled to locate the motor precisely;
2, driven by stepping motor subdivision driver, the step angle becomes small, such as the driver operates in 10 segments of the state, the step angle only for "natural" 1/10 step motor, it is said: "when the driver operating in segments of the whole step state, the control system of each a stepper motor pulse, rotate 1.8 degrees; and subdivision drive work in 10 segments when the motor rotation only 0.18 degrees", this is the basic concept of subdivision. The subdivision function is entirely generated by the phase current of the drive by precisely controlling the motor, independent of the motor.
3, what are the advantages of driver segmentation, and why is it necessary to use subdivision functions?
The main advantage of driver subdivision is that the low
frequency oscillation of the motor is completely eliminated. Low frequency oscillation is a stepper motor (especially reactive motor) the inherent characteristics, and is the only way to eliminate the subdivision of it, if you step motor sometimes work in the resonance region (such as walking, arc) is the only choice to choose driver. The output torque of the motor is improved. Especially for three-phase reactive motors, the torque ratio increases by about 30-40% without subdivision. The resolution of the motor is improved. Because of reducing the step angle and increasing the uniformity of the step distance, it is self-evident that the resolution of the motor is increased.
Basic knowledge of stepper motor drive systems
1. Common sense of the system: stepping motor and stepping motor driver constitute stepping motor drive system. The performance of the stepping motor drive system depends not only on the performance of the stepper motor itself, but also on the performance of the stepper motor driver. The research of stepping motor driver is almost synchronous with the research of stepping motor.
2. System overview: stepper motor is an electrical pulse into angular displacement of the implementation of components. When the stepper motor driver receives a pulse signal (from the contro
ller), it drives the stepper motor to set the direction of rotation of a fixed angle (called "step"), it is the rotation of the fixed point of the operation step by step.
3, system control: stepper motor can not be directly connected
to DC or AC power supply, you must use a dedicated drive power (stepper motor drive). The controller (pulse generator) through a control pulse to control the amount of angular displacement, so as to achieve the purpose of accurate positioning; at the same time by controlling the pulse frequency to control the motor rotation speed and acceleration, so as to achieve the purpose of speed.
4, use: stepper motor is a special motor control, as the actuator, electromechanical integration is one of the key products, along with the development of microelectronics and computer technology (stepper motor drive performance improvement), demand for stepper motor grow with each passing day. Stepping motor has no accumulation error in operation, so it is widely used in various automatic control systems, especially open-loop control system.
5, stepper motor classification according to the structure: stepper motor is also called a pulse motor, including reactive stepping motor (VR), permanent magnet stepper motor (PM), hybrid stepping motor (HB) and so on.
(1) reaction stepping motor: also called induction type, hysteresis type or reluctance type stepping motor. The stator and rotor are made of soft magnetic material,
The uniform distribution of large magnetic pole on the stator with multiphase excitation winding, stator and rotor evenly distributed around the teeth and grooves, permeability changes using electricity generated torque. Is generally three or four, five or six phase; can achieve high torque output (larger power
consumption, current up to 20A, higher driving voltage); small step angle (the minimum can be 10 '); power without cogging torque; small damping motor, single step operation (the pulse frequency is very low when the shock takes a long time to start); and the operation of high frequency.
(2) permanent magnet stepper motor: motor rotor comprises a permanent magnetic material, a multiphase excitation winding stator is made of soft magnetic materials, stator and rotor teeth and no surrounding groove, energized by permanent magnet and stator current magnetic field interact to produce torque. Usually two or four; the output torque is small (smaller power consumption, current driving voltage is less than 2A, 12V); large step angle (e.g. 7.5 degrees, 15 degrees, 22.5 degrees and so on); power has a certain torque starting and operating frequency is low.
(3) hybrid stepping motor: also called permanent magnet reaction type and permanent magnet induction stepping motor. It combines the advantages of permanent magnet and reaction type. The stator and the four phase step motor (but no difference between the two magnetic poles of the same phase, and the two pole winding of N produced, S must have the same polarity), the rotor structure is more complex (rotor internal cylindrical permanent magnet, two coats of soft magnetic materials, the surrounding denticulate and groove). Usually two or four; to supply positive and negative pulse signal; the output torque is large (permanent magnet power consumption is relatively small); a permanent magnet small step angle (typically 1.8 degrees); power without positioning torque; starting and running high frequency; is the development of a
rapid step motor.
6, stepper motor classification according to the way of operation: can be divided into power and servo type two.
(1) power type: output torque is larger, can directly drive larger load (general use reaction type, hybrid stepping motor).
(2) servo type: the output torque is small and can only drive smaller loads (usually using permanent m
agnet and hybrid stepping motors).
7, the choice of stepper motor:
(1) first select the type, followed by the specific varieties and models.
reaction in the shaft
(2) the reaction type and permanent magnet type and three kinds of hybrid stepping motor performance, dimensions, installation methods, types of pulse power supply and control circuit are different, the price difference is also great, when the choice should be considered.
(3) stepping motor with control IC should be given priority.
8. Basic parameters of stepping motor:
(1) the intrinsic step angle of the motor: it represents the angle of rotation of the motor when each step of the control system sends a pulse signal. The factory motor gives a step angle value, such as 86BYG250A type motor is given a value of

版权声明：本站内容均来自互联网，仅供演示用，请勿用于商业和其他非法用途。如果侵犯了您的权益请与我们联系QQ:729038198，我们将在24小时内删除。