This step angle is determined by the motor planning structure
The operation form of the stepper motor The basic operation form of the stepper motor is called 'excitation form', which can make the stepper motor work in the full step form, half step form and micro step form, during which the micro step form can effectively reduce the step The noise of the phase current into the motor can improve the inherent noise and vibration problems of the stepper motor. The following three types of excitation will be introduced. The full-step form is called the full-step form, which is a fixed step angle operation based on the inherent structure of the motor. An electrical pulse The stepping motor travels a step angle. This step angle is determined by the motor planning structure, and it can be understood that the motor rotates at the maximum step angle.
The half-step form The half-step form is a step determined by the inherent structure of the motor Half of the angle of view performs step rotation. As shown in the figure below, the total number of poles of the stepper motor is 4 levels, and the corresponding step angle is 90 degrees. In the half-step form, each pulse of the step motor rotates 45 degrees. . Microstep form The microstep form is similar to the half-step form, with a smaller step angle, which is 1/4 step, 1/8 step, 1/16 step, which can reach a high degree of subdivision. Fan system The corresponding step perspective is at Step by step The distance angle is multiplied by the micro-step coefficient. The smaller the step angle of the stepper motor, the higher the processing accuracy required, and the larger the error of the step viewpoint at the corresponding microstep. The motor-driven driver stepper motor cannot be directly connected. To work on industrial frequency communication or DC power supply, it is necessary to use a dedicated stepper motor driver, which consists of a pulse generation control unit, a power drive unit, a maintenance unit, etc. As shown in the figure below. The drive unit is directly coupled to the stepper motor It can also be understood as the power interface of the stepper motor microcomputer controller.
The following will use the MCU and the separation device system as an example. The MCU is suitable for controlling the brain of the motor. It sends the step angle of the motor and the rolling direction to the discrete equipment. And the number of repetitions, and according to the signal announced by the MCU, discrete equipment will expand the voltage and current and send it to the motor, and then drive the motor to roll. As shown in the figure above, the system uses the MCU and motor to control the driver IC. From the input control Stepper motor controller IC can be divided into phase input type and clock input type. Phase input type refers to each excitation of the motor. The current direction of the phase is controlled by the input signal, and the clock input type means that the driving of the motor is controlled by the pulse signal. The phase input force type phase input force type motor driver requires two phases of control signals, A and B, only the clock signal and the control signal. MCUs do more transport operations. The control interface of the clock-in type clock-in type motor driver requires a clock signal (single pulse signal) input. Its control signal is relatively simple and the MCU occupies less resources. Motor drive safety skills are powered on Reset function (POR) The power-on reset function will monitor the power of the motor driver and the motor drive controller. To avoid motor operation problems, it will forcibly close the output signal until the power supply voltage remains stable. As shown in the figure below. Overcurrent detection function ( ISD) The over-current shutdown function will monitor the current of the output unit. If the current exceeds the specified value, the output will be forcibly closed. The function is to temporarily stop the IC output when a short circuit occurs. As shown below. Thermal Shutdown Function (TSD) The thermal shutdown function is to close the output when the temperature of the driver chip of the driver controlled by the motor exceeds the specified value, and maintain the condition until the temperature drops.
