Electrical Induction Iron Motors Frame

The working principle of stepper motor drives,special attention must be paid in the process of step

motor processing when reversing.To make the stepper motor can smooth transition when reversing,less wrong step,sign should be set in each step.20 h unit you for step motor is turn flags;21 h unit reversal sign from you.In the forward,not only to forward sign an assignment,and at the same time An assignment to reverse logo;In a reversal.Like this,when the stepper motor commutator,can be the last time the location of the reverse movement as a starting point,to avoid the motor commutator generated when the wrong step.1.The working principle of stepper motor The stepper motor as matters phase stepping motor,with one polarity dc supply.As long as each phase winding of stepping motor by appropriate timing electricity,can make the stepper motor step by step.Figure 1 is the four phase reactive stepper motor working principle diagram.Switch electric vehicle motor at the start of SB,turning on the power supply of SA,SC and SD disconnect,B pole and the rotor tooth alignment 0,3,at the same time,the rotor's 1,4 teeth and C and D phase winding magnetic pole produce wrong tooth,tooth is 2,5,and D,A phase winding magnetic pole produce the wrong tooth.When,turning on the power supply switch SC SB,SA,SD disconnected,due to the magnetic field lines of C phase winding and the role of 1,4 teeth between the lines of magnetic force,make the rotor rotation,1,4 teeth alignment and C phase winding of magnetic pole.Tooth and A,B and 0 and 3 phase winding produce wrong tooth,tooth is 2,5,and A and D phase winding magnetic pole produce the wrong tooth.So on,A,B,C,D four phase winding turns Power supply,the rotor will be along the direction of A,B,C,D.Four phase stepper motor,depending on the current order can be divided into four single,double four taps,eight three works.Single four taps and double four interval Angle are equal,but four of the rotational torque is small.Eight works was taken steps away from the Angle of the single four taps and double four half,therefore,eight beats working can keep high rotational torque and can improve the control precision.List four taps,double four and eight beats working power supply electric timing and waveform respectively as shown in figure 2.A,b,c is shown in 

(2) the stepper motor drive system based on AT89C2051 circuit principle AT89C2051 will

control pulse output from P1 mouth P1.4 ~ P1.7,in 9014,after 74 ls14 reversed-phase after 9014

amplification control,photoelectric switch,photoelectric isolation,by the power tube TIP122

amplifier,the pulse signal to voltage and current drive stepping motor each phase winding.The stepper motor with different pulse signal respectively as a forward,reverse,speed, Slow down and stop.Figure in the L1 a phase winding for wholesalemotor.blogspot.com stepping

motor.Selection of AT89C2051 22 MHZ crystal vibration frequency,the higher is the purpose of the crystals in order to minimize AT89C2051 under way 2 the influence of the pulse signal to the upper machine cycle.50 Ω resistance is an external resistor,current-limiting role,is also an element to improve circuit time constant.From D1 to D4 fly-wheel diode,take the counter electromotive force produced by the motor winding through the fly-wheel diode (D1 - D4) and attenuation,thus protecting

the power tube TIP122 from being damaged.Stepping motor drive system schematic circuit diagram on 50 Ω external resistor in parallel 200 mu F capacitance,can improve the injection of the stepper motor winding current pulse edge,improve the 8500w

gasoline generator performance of step motor of high frequency.With 200 Ω fly-wheel

diode series resistance can reduce the discharge time constant circuit,pulse current in the winding

along the steepening,smaller current fall time,also improve the working performance of the high

frequency.2.The software design The drive according to dial the code switch KX,there are three kinds

of different combination of KY works to choose from:Mode 1 is the interrupt mode:P3.5 (INT1) is a

step pulse input,P3.7 for positive &negative pulse input.Upper machine (PC or MCU) is connected to a

drive with only 2 lines.Mode 2 for serial communication mode:upper machine (PC or single chip

microcomputer) will control commands sent to the three-phase asynchronous motor,the drive to complete the control commands to control the process.3 to dial the code switch control way:by the different combination of K1 ~ K5,direct control of stepping motor.When power on or press the reset button to KR,AT89C2051 to detect the state of dial the code switch KX,KY,according to the different combination of KX,KY,into a different way of working.Here are 1 program flow diagram and the source program.Removed from some old devices of step motor (usually does not damage the motor),as it generally need to drive your own design.The following case is removed from a Japanese old printer

designed stepper motor drives.First introduce the working principle of stepper motor,and then

introduces the software and hardware design of the drive.