步进电机及单片机英文文献及翻译.pdf

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1、外文文献：外文文献：Knowledge of the stepper motorKnowledge of the stepper motorWhat is a stepper motor： Stepper motor is a kind of electrical pulses into angular displacement of theimplementing agency. Popular little lesson: When thedriver receives astep pulsesignal, it will drive a stepper motor to set the

2、direction of rotation at a fixedangle (and the step angle). You can control the number of pulses to control theangular displacement, so as to achieve accurate positioning purposes; the same timeyou can control the pulse frequency to control the motor rotation speed andacceleration, to achieve speed

3、control purposes.What kinds of stepper motor sub-： In three stepper motors: permanent magnet (PM), reactive (VR) and hybrid (HB)permanent magnet stepper usually two-phase, torque, and smaller, step angle ofdegrees or the general 15 degrees; reaction step is generally three-phase, canachieve high tor

4、que output, step angle of degrees is generally, but the noise andvibration are large. 80 countries in Europe and America have been eliminated; hybridstepper is a mix of permanent magnet and reactive advantages. It consists of twophases and the five-phase: two-phase step angle of degrees while the ge

5、neralfive-phase step angle of degrees generally. The most widely used Stepper Motor.What is to keep the torque (HOLDING TORQUE)How much precision stepper motor? Whether the cumulative： The general accuracy of the stepper motor step angle of 3-5%, and not cumulative.Stepper motor to allow the minimum

6、 amount of surface temperatureStepper motor to allow the minimum amount of surface temperature：Stepper motor causes the motor temperature is too high the first magneticdemagnetization, resulting in loss of torque down even further, so the motor surfacetemperature should be the maximum allowed depend

7、ing on the motor demagnetizationof magnetic material points; Generally speaking, the magnetic demagnetizationpoints are above 130 degrees Celsius, and some even as high as 200 degrees Celsius,so the stepper motor surface temperature of 80-90 degrees Celsius is normal.How to determine the stepper mot

8、or driver DC power supply： A. Determination of the voltageHybrid stepping motor driver power supply voltage is generally a wide range (suchas the IM483 supply voltage of 12 48VDC), the supply voltage is usually basedon the work of the motor speed and response to the request to choose. If the motorop

9、erating speed higher or faster response to the request, then the voltage valueis high, but note that the ripple voltage can not exceed the maximum input voltageof the drive, or it may damage the drive. B. Determination of CurrentPower supply current is generally based on the output phase current dri

10、ve I todetermine. If a linear power supply, powersupply current is generally preferableto times the I; if we adopt the switching power supply, power supply current isgenerally preferable to I, to times.The main characteristics of stepping motor： A stepper motor drive can be added operate pulse drive

11、 signal must be no pulsewhen the stepper motor at rest, such asIf adding the appropriate pulse signal, it will to a certain angle (called the stepangle) rotation. Rotation speed and pulse frequency is proportional to. 2 Dragon step angle stepper motor version is degrees, 360 degrees around, takes48

12、pulses to complete. 3steppermotorhasinstantstartandrapidcessationofsuperiorcharacteristics.Change the pulse of the order of 4, you can easily change the direction of rotation.Therefore, the current printers, plotters, robotics, and so devices are the coreof the stepper motor as the driving force.Ste

13、pper motor control exampleWe use four-phase unipolar stepper motor as an example. The structure shown inFigure 1: Four four-phase winding leads (as opposed to phase A1 A2 B1 phase phase B2) andtwo public lines (to the power of positive). The windings of one phase to the powerof the ground. So that t

14、he windings will be inspired. We use four-phase eight-beatcontrol, ie, 1 phase 2 phase alternating turn, would enhance resolution. perstep can be transferred to control the motor excitation is transferred in orderas follows: If the requirements of motor reversal, the transmission excitation signal c

15、anbe reversed. 2 control schemeControl system block diagram is as follows The program uses AT89S51 as the main control device. It is compatible with theAT89C51, but also increased the SPI interface and the watchdog module, which notonlymakesthedebuggingprocessbecomeseasyandalsomorestable.Themicrocon

16、troller in the program mainly for field signal acquisition and operationof the stepper motor to calculate the direction and speed information. Then sentto the CPLD.CPLD with EPM7128SLC84-15, EPM7128 programmable logic device of large-scale, forthe ALTERA companys MAX7000 family. High impedance, elec

17、trically erasable andother characteristics, can be used for the 2500 unit, the working voltage of +5V. CPLD receivesinformation sent from the microcontroller after converted tothecorresponding control signal output to the stepper motor drive. Put the controlsignal drives the motor windings after the

18、 input, to achieve effective control ofthe motor. The hardware structure of the motor driveMotor drive using the following circuit: R1-R8 in which the resistance value of 320. R9-R12 resistance value . Q1-Q4as Darlington D401A, Q5-Q8 for the S8550. J1, J2 and the stepper motor connectedto the six-le

19、ad。Advantages and disadvantages of stepper motorAdvantages 1. The motor rotation angle is proportional to the number of pulses; 2. When the motor stopped with a maximum torque (when the winding excitationtime); 3. Since the accuracy of each step in the three per cent to five per cent, andthe error w

20、ill not accumulate to the next step and thus has better positionalaccuracy and repeatability of movement; 4. Excellent response from the stop and reverse; 5. In the absence of brush, high reliability, it just depends on the life ofthe motor bearing life; 6. Motor response only determined by the numb

21、er of input pulses, which can beused open loop control, which makes the motor and control structure can berelatively simpleSystem cost 7. Just load directly connected to the motor shaft can also be extremely slowsynchronous rotation. 8. Speed ?is proportional to the pulse frequency, and thus a relat

22、ively widespeed range.Shortcomings1. If not properly controlled prone to resonance;2. Difficult operation to a higher speed.3. Difficult to obtain high torque4. There is no advantage in terms of volume weight, low energy efficiency.5. Over load will destroy the synchronization, the work will be issu

23、ed whenhigh-speed vibration and noise.Stepper motor drive requirements(1) to provide fast rise and fall of current speed, the current waveform as closeas possible rectangle.For the period ended with the release of the loop current flow, to reduce the windingends of the back electromotive force, to a

24、ccelerate the current decay.(2) rhyme with higher power and efficiency.Stepper motor driver, which is the control pulse signal emitted into the angulardisplacement of the stepper motor, or: the control system sends a pulse signal eachthrough the stepper motor drive to rotate a step angle. That is th

25、e stepper motorspeed is proportional to the frequency and pulse signals. Therefore, the frequencycontrol pulse signal, to be precise motor speed control; control the number of steppulses to connect the motor accurately. Stepper motor drive there are many, weshould take a reasonable choice of power r

26、equirements of the drive, the followingwere introduced various types of typical drive.The latest technological developmentsDomestic and international research on the sub-drive technology is very active,high-performance sub-driver circuit can be broken downinto thousands or even anysubdivision. Now a

27、ble to do complicated calculations to make after the breakdownof uniform step angle, which greatly improves the resolution of stepper motor pulses,reduce or eliminate the vibration, noise and torque ripple, the stepper motor ismore class server feature.The actual role of step angle: in the absence o

28、f sub-drive, the user select adifferent number of phases depends mainly on the stepper motor to meet their ownrequirements on the step angle ，If you use the sub-drive, the user can change thedrive number of segments, can dramatically change the actual step angle steppermotor phases of change in the

29、role of the actual step angle is almost negligible.Introduction of AT89C51Introduction of AT89C51DescriptionThe AT89C51 is a low-power, high-performance CMOS 8-bit microcomputer with 4Kbytes of Flash programmable and erasable read only memory (PEROM). The device ismanufactured using Atmels high -den

30、sity nonvolatile memory technology and iscompatible with the industry-standard MCS-51 instruction set and pinout. Theon-chip Flash allows the program memory to be reprogrammed in-system or by aconventional nonvolatile memory programmer. By combining a versatile 8-bit CPU withFlash on a monolithic ch

31、ip, the Atmel AT89C51 is a powerful microcomputer whichprovides a highly-flexible and cost-effective solution to many embedded controlapplications.Function characteristicThe AT89C51 provides the following standard features: 4K bytes of Flash, 128bytes of RAM, 32 I/O lines, two 16-bit timer/counters,

32、 a five vector two-levelinterrupt architecture, a full duplex serial port, on-chip oscillator and clockcircuitry. In addition, the AT89C51 is designed with static logic for operationdown to zero frequency and supports two software selectable power saving modes.The Idle Mode stops the CPU while allow

33、ing the RAM, timer/counters, serial portand interrupt system to continue functioning. The Power-down Mode saves the RAMcontents but freezes the oscillator disabling all other chip functions until thenext hardware reset.Pin DescriptionVCC：Supply voltage.GND：Ground.Port 0：Port 0 is an 8-bit open-drain

34、 bi-directional I/O port. As an output port, each pincan sink eight TTL inputs. When 1s are written to port 0 pins, the pins can be usedas highimpedance0 may also be configured to be the multiplexed loworderaddress/data bus during accesses to external program and data memory. In this modeP0 has inte

35、rnal 0 also receives the code bytes during Flash programming,andoutputs the code bytes during programverification. External pullups are requiredduring programverification.Port 1Port 1 is an 8-bit bi-directional I/O port with internal pullups.The Port 1output buffers can sink/source four TTL 1s are w

36、ritten to Port 1 pins they arepulled high by the internal pullups and can be used as inputs. As inputs,Port 1pins that are externally being pulled low will source current (IIL) because of theinternal 1 also receives the low-order address bytes during Flash programming andverification.Port 2Port 2 is

37、 an 8-bit bi-directional I/O port with internal pullups.The Port 2output buffers can sink/source four TTL 1s are written to Port 2 pins they arepulled high by the internal pullups and can be used as inputs. As inputs,Port 2pins that are externally being pulled low will source current, because of the

38、internal 2 emits the high-order address byte during fetches from external programmemory and during accesses to external data memory that use 16-bit addresses. Inthis application, it uses strong internal pullupswhen emitting 1s. During accessesto external data memory that use 8-bit addresses, Port 2

39、emits the contents of theP2 Special Function 2 alsoreceives the high-orderaddress bits andsome controlsignals during Flash programming and verification.Port 3Port 3 is an 8-bit bi-directional I/O port with internal pullups.The Port 3output buffers can sink/source four TTL 1s are written to Port 3 pi

40、ns they arepulled high by the internal pullups and can be used as inputs. As inputs,Port 3pins that are externally being pulled low will source current (IIL) because of the3 also serves the functions of various special features of the AT89C51 as listedbelow:Port 3 also receives some control signals

41、forFlash programming andverification.RSTReset input. A high on this pin for two machine cycles while the oscillatoris running resets the device.ALE/PROGAddress Latch Enable output pulse for latching the low byte of the addressduring accesses to external memory. This pin is also the program pulse inp

42、ut (PROG)during Flash normal operation ALE isemitted at a constant rate of 1/6 theoscillator frequency, and may be used for external timing or clocking purposes.Note, however, that one ALE pulse is skipped during each access to external DataMemory.If desired, ALE operation can be disabled by setting

43、 bit 0 of SFR location 8EH.With the bit set, ALE is active only during a MOVX or MOVC instruction. Otherwise,the pin is weakly pulled high. Setting the ALE-disable bit has no effect if themicrocontroller is in external execution mode.PSENProgram Store Enable is the read strobe to external program th

44、e AT89C51 isexecuting code from external program memory, PSEN is activated twice each machinecycle, except that two PSEN activations are skipped during each access to externaldata memory.EA/VPPExternal Access Enable. EA must be strapped to GND in order to enable the deviceto fetch code from external

45、 program memory locations starting at 0000H up to FFFFH.Note, however, that if lock bit 1 is programmed, EA will be internally latched onshould be strapped to VCC for internal program pin also receives the 12-voltprogrammingenablevoltage(VPP)duringFlashprogramming,forpartsthatrequire12-volt VPP.XTAL

46、1Input to the inverting oscillator amplifier and input to the internal clockoperating circuit.XTAL2Output from the inverting oscillator amplifier.Oscillator CharacteristicsXTAL1 and XTAL2 are the input and output, respectively,of an invertingamplifier which can be configured for use as an on-chip os

47、cillator, as shown inFigure a quartz crystal or ceramic resonator may be used. To drive the device froman external clock source, XTAL2 should be left unconnected while XTAL1 is drivenas shown in Figure are no requirements on the duty cycle of the external clocksignal,sincetheinputtotheinternalclocki

48、ngcircuitryisthroughadivide-by-two flip-flop, but minimum and maximum voltage high and low timespecifications must be observed.Figure 1. Oscillator Connections Figure 2. External Clock DriveConfigurationIdle ModeIn idle mode, the CPU puts itself to sleep while all the onchip peripheralsremain active

49、. The mode is invoked by software. The content of the on-chip RAM andall the special functions registers remain unchanged during this mode. The idlemode can be terminated by any enabled interrupt or by a hardware should be notedthat when idle is terminated by a hard ware reset, the device normally r

50、esumesprogram execution,from where it left off, up to two machine cycles before theinternal reset algorithm takes control. On-chip hardware inhibits access tointernal RAM in this event, but access to the port pins is not inhibited. Toeliminate the possibility of an unexpected write to a port pin whe