1、外文文獻： Knowledge of the stepper motorWhat is a stepper motor： Stepper motor is a kind of electrical pulses into angular displacement of the implementing agency. Popular little lesson: When the driver receives a step pulse signal, it will drive a stepper motor to set the direction of rotation at a fix

2、ed angle (and the step angle). You can control the number of pulses to control the angular displacement, so as to achieve accurate positioning purposes; the same time you can control the pulse frequency to control the motor rotation speed and acceleration, to achieve speed control purposes.What kind

3、s 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 of 7.5 degrees or the general 15 degrees; reaction step is generally three-phase, can achieve high torque output, step an

4、gle of 1.5 degrees is generally, but the noise and vibration are large. 80 countries in Europe and America have been eliminated; hybrid stepper is a mix of permanent magnet and reactive advantages. It consists of two phases and the five-phase: two-phase step angle of 1.8 degrees while the general fi

5、ve-phase step angle of 0.72 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 a

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

7、ing on the motor demagnetization of magnetic material points; Generally speaking, the magnetic demagnetization points 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

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

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

10、rent drive I to determine. If a linear power supply, power supply current is generally preferable 1.1 to 1.3 times the I; if we adopt the switching power supply, power supply current is generally preferable to I, 1.5 to 2.0 times.The main characteristics of stepping motor： A stepper motor drive can

11、be added operate pulse drive signal must be no pulse when the stepper motor at rest, such asIf adding the appropriate pulse signal, it will to a certain angle (called the step angle) rotation. Rotation speed and pulse frequency is proportional to. 2 Dragon step angle stepper motor version is 7.5 deg

12、rees, 360 degrees around, takes 48 pulses to complete. 3 stepper motor has instant start and rapid cessation of superior characteristics.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 cor

13、e of the stepper motor as the driving force.Stepper motor control exampleWe use four-phase unipolar stepper motor as an example. The structure shown in Figure 1: Four four-phase winding leads (as opposed to phase A1 A2 B1 phase phase B2) and two public lines (to the power of positive). The windings

14、of one phase to the power of the ground. So that the windings will be inspired. We use four-phase eight-beat control, ie, 1 phase 2 phase alternating turn, would enhance resolution. 0.9 per step can be transferred to control the motor excitation is transferred in order as follows: If the requirement

15、s of motor reversal, the transmission excitation signal can be reversed. 2 control schemeControl system block diagram is as follows The program uses AT89S51 as the main control device. It is compatible with the AT89C51, but also increased the SPI interface and the watchdog module, which not only mak

16、es the debugging process becomes easy and also more stable. The microcontroller in the program mainly for field signal acquisition and operation of the stepper motor to calculate the direction and speed information. Then sent to the CPLD.CPLD with EPM7128SLC84-15, EPM7128 programmable logic device o

17、f large-scale, for the ALTERA companys MAX7000 family. High impedance, electrically erasable and other characteristics, can be used for the 2500 unit, the working voltage of +5 V. CPLD receives information sent from the microcontroller after converted to the corresponding control signal output to th

18、e stepper motor drive. Put the control signal drives the motor windings after the input, to achieve effective control of the motor. 2.1 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 2.2K. Q1-Q4 as

19、 Darlington D401A, Q5-Q8 for the S8550. J1, J2 and the stepper motor connected to the six-lead。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 excitation tim

20、e); 3. Since the accuracy of each step in the three per cent to five per cent, and the error will not accumulate to the next step and thus has better positional accuracy and repeatability of movement; 4. Excellent response from the stop and reverse; 5. In the absence of brush, high reliability, it j

21、ust depends on the life of the motor bearing life; 6. Motor response only determined by the number of input pulses, which can be used open loop control, which makes the motor and control structure can be relatively simpleSystem cost 7. Just load directly connected to the motor shaft can also be extr

22、emely slow synchronous rotation. 8. Speed is proportional to the pulse frequency, and thus a relatively wide speed 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

23、 weight, low energy efficiency.5. Over load will destroy the synchronization, the work will be issued when high-speed vibration and noise.Stepper motor drive requirements(1) to provide fast rise and fall of current speed, the current waveform as close as possible rectangle.For the period ended with

24、the release of the loop current flow, to reduce the winding ends of the back electromotive force, to accelerate the current decay.(2) rhyme with higher power and efficiency.Stepper motor driver, which is the control pulse signal emitted into the angular displacement of the stepper motor, or: the con

25、trol system sends a pulse signal each through the stepper motor drive to rotate a step angle. That is the stepper motor speed is proportional to the frequency and pulse signals. Therefore, the frequency control pulse signal, to be precise motor speed control; control the number of step pulses to con

26、nect the motor accurately. Stepper motor drive there are many, we should take a reasonable choice of power requirements of the drive, the following were introduced various types of typical drive.The latest technological developmentsDomestic and international research on the sub-drive technology is v

27、ery active, high-performance sub-driver circuit can be broken down into thousands or even any subdivision. Now able to do complicated calculations to make after the breakdown of uniform step angle, which greatly improves the resolution of stepper motor pulses, reduce or eliminate the vibration, nois

28、e and torque ripple, the stepper motor is more class server feature.The actual role of step angle: in the absence of sub-drive, the user select a different number of phases depends mainly on the stepper motor to meet their own requirements on the step angle，If you use the sub-drive, the user can cha

29、nge the drive number of segments, can dramatically change the actual step angle stepper motor phases of change in the role of the actual step angle is almost negligible. Introduction of AT89C51DescriptionThe AT89C51 is a low-power, high-performance CMOS 8-bit microcomputer with 4K bytes of Flash pro

30、grammable and erasable read only memory (PEROM). The device is manufactured using Atmels high-density nonvolatile memory technology and is compatible with the industry-standard MCS-51 instruction set and pinout. The on-chip Flash allows the program memory to be reprogrammed in-system or by a convent

31、ional nonvolatile memory programmer. By combining a versatile 8-bit CPU with Flash on a monolithic chip, the Atmel AT89C51 is a powerful microcomputer which provides a highly-flexible and cost-effective solution to many embedded control applications.Function characteristicThe AT89C51 provides the fo

32、llowing standard features: 4K bytes of Flash, 128 bytes of RAM, 32 I/O lines, two 16-bit timer/counters, a five vector two-level interrupt architecture, a full duplex serial port, on-chip oscillator and clock circuitry. In addition, the AT89C51 is designed with static logic for operation down to zer

33、o frequency and supports two software selectable power saving modes. The Idle Mode stops the CPU while allowing the RAM, timer/counters, serial port and interrupt system to continue functioning. The Power-down Mode saves the RAM contents but freezes the oscillator disabling all other chip functions

34、until the next hardware reset.Pin DescriptionVCC：Supply voltage.GND：Ground.Port 0：Port 0 is an 8-bit open-drain bi-directional I/O port. As an output port, each pin can sink eight TTL inputs. When 1s are written to port 0 pins, the pins can be used as highimpedance inputs.Port 0 may also be configur

35、ed to be the multiplexed loworder address/data bus during accesses to external program and data memory. In this mode P0 has internal pullups.Port 0 also receives the code bytes during Flash programming,and outputs the code bytes during programverification. External pullups are required during progra

36、mverification.Port 1Port 1 is an 8-bit bi-directional I/O port with internal pullups.The Port 1 output buffers can sink/source four TTL inputs.When 1s are written to Port 1 pins they are pulled high by the internal pullups and can be used as inputs. As inputs,Port 1 pins that are externally being pu

37、lled low will source current (IIL) because of the internal pullups.Port 1 also receives the low-order address bytes during Flash programming and verification.Port 2Port 2 is an 8-bit bi-directional I/O port with internal pullups.The Port 2 output buffers can sink/source four TTL inputs.When 1s are w

38、ritten to Port 2 pins they are pulled high by the internal pullups and can be used as inputs. As inputs,Port 2 pins that are externally being pulled low will source current, because of the internal pullups.Port 2 emits the high-order address byte during fetches from external program memory and durin

39、g accesses to external data memory that use 16-bit addresses. In this application, it uses strong internal pullupswhen emitting 1s. During accesses to external data memory that use 8-bit addresses, Port 2 emits the contents of the P2 Special Function Register.Port 2 also receives the high-order addr

40、ess bits and some control signals during Flash programming and verification.Port 3Port 3 is an 8-bit bi-directional I/O port with internal pullups.The Port 3 output buffers can sink/source four TTL inputs.When 1s are written to Port 3 pins they are pulled high by the internal pullups and can be used

41、 as inputs. As inputs,Port 3 pins that are externally being pulled low will source current (IIL) because of the pullups.Port 3 also serves the functions of various special features of the AT89C51 as listed below:Port 3 also receives some control signals for Flash programming and verification.RSTRese

42、t input. A high on this pin for two machine cycles while the oscillator is running resets the device.ALE/PROGAddress Latch Enable output pulse for latching the low byte of the address during accesses to external memory. This pin is also the program pulse input (PROG) during Flash programming.In norm

43、al operation ALE is emitted at a constant rate of 1/6 the oscillator frequency, and may be used for external timing or clocking purposes. Note, however, that one ALE pulse is skipped during each access to external Data Memory.If desired, ALE operation can be disabled by setting bit 0 of SFR location

44、 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 the microcontroller is in external execution mode.PSENProgram Store Enable is the read strobe to external program memory.When the AT89C

45、51 is executing code from external program memory, PSEN is activated twice each machine cycle, except that two PSEN activations are skipped during each access to external data memory.EA/VPPExternal Access Enable. EA must be strapped to GND in order to enable the device to fetch code from external pr

46、ogram memory locations starting at 0000H up to FFFFH. Note, however, that if lock bit 1 is programmed, EA will be internally latched on reset.EA should be strapped to VCC for internal program executions.This pin also receives the 12-volt programming enable voltage(VPP) during Flash programming, for

47、parts that require12-volt VPP.XTAL1Input to the inverting oscillator amplifier and input to the internal clock operating circuit.XTAL2Output from the inverting oscillator amplifier.Oscillator CharacteristicsXTAL1 and XTAL2 are the input and output, respectively,of an inverting amplifier which can be

48、 configured for use as an on-chip oscillator, as shown in Figure 1.Either a quartz crystal or ceramic resonator may be used. To drive the device from an external clock source, XTAL2 should be left unconnected while XTAL1 is driven as shown in Figure 2.There are no requirements on the duty cycle of t

49、he external clock signal, since the input to the internal clocking circuitry is through a divide-by-two flip-flop, but minimum and maximum voltage high and low time specifications must be observed. Figure 1. Oscillator Connections Figure 2. External Clock Drive ConfigurationIdle ModeIn idle mode, th

50、e CPU puts itself to sleep while all the onchip peripherals remain active. The mode is invoked by software. The content of the on-chip RAM and all the special functions registers remain unchanged during this mode. The idle mode can be terminated by any enabled interrupt or by a hardware reset.It sho

51、uld be noted that when idle is terminated by a hard ware reset, the device normally resumes program execution,from where it left off, up to two machine cycles before the internal reset algorithm takes control. On-chip hardware inhibits access to internal RAM in this event, but access to the port pin

52、s is not inhibited. To eliminate the possibility of an unexpected write to a port pin when Idle is terminated by reset, the instruction following the one that invokes Idle should not be one that writes to a port pin or to external memory.Power-down ModeIn the power-down mode, the oscillator is stopp

53、ed, and the instruction that invokes power-down is the last instruction executed. The on-chip RAM and Special Function Registers retain their values until the power-down mode is terminated. The only exit from power-down is a hardware reset. Reset redefines the SFRs but does not change the on-chip RA

54、M. The reset should not be activated before VCC is restored to its normal operating level and must be held active long enough to allow the oscillator to restart and stabilize.中文譯文： 步進電機的知識什么是步進電機：步進電機是一種把電脈沖轉化為角位移的執行機構。通俗的說：當驅動程序收到一個步進脈沖信號，將驅動步進電機軸旋轉一個固定的角度（步進角）。您可以通過控制脈沖個數來控制角位移，從而達到準確定位的目的;同時，你可以通

55、過控制脈沖頻率來控制電機的旋轉速度和加速度，實現速度控制的目的。步進電機的種類：步進電機分為三種：永磁式（PM），反應式（VR）和混合式（HR）永磁式步進電機一般為兩相，轉矩和體積較小，步進角一步7.5度或15度;反應式一般有三相可以實現大轉矩輸出，步進角一般是1.5度，但噪聲和振動大。在歐洲和美洲80個國家已被淘汰;混合式步進是混合了永磁式和反應的優勢。它由兩相和五相：一般兩相的步距角是1.8度，而的五相步距角為0.72度。是使用最廣泛的的步進電機。步進電機允許的最高表面溫度步進電機溫度過高首先會的磁性材料退磁，導致轉矩降低甚至失步，電機表面溫度允許的最大值取決于的磁性材料退磁點;一般來說，

56、磁性材料退磁點在攝氏130度以上有些材料甚至高達攝氏200度高，所以步進電機表面溫度在攝氏80-90度是正常的。 步進電機精度為多少？是否累積一般步進電機的精度為步進角的3-5%，且不累積 如何確定步進電機驅動器直流電源A.電壓確定混合式步進電機驅動器的電源電壓范圍較廣（比如IM483的供電電壓1248VDC），電源電壓通常根據電機的轉速和響應要求來選擇。如果要求較快的運行速度較高的響應速度就選用較高的電壓，但注意電源電壓的峰值不能超過驅動器的最大輸入電壓，否則可能會損壞驅動器。B.電流確定電源電流一般根據輸出相電流I來確定。如果采用線性電源，電源電流一般可取I的1.11.3倍;如果采用開關電

57、源，電源電流一般可取I的1.52.0倍。步進電機的主要特性 在步進電機關機時要確保沒有脈沖信號，當電機運行時如果加入適當的脈沖信號，它會轉過一定的角度（稱為步距角是）。轉速與脈沖頻率成正比。 2龍式步進電機步距角7.5度，旋轉360度，需要48個脈沖來完成。 3步進電機具有快速啟動和停止的優良特性。4只要改變脈沖，可以很容易地改變電機軸旋轉的方向。因此，目前的打印機，繪圖儀，機器人設備以步進電機作為動力核心。步進電機控制的例子我們以四相單極步進電機為例：四個相繞組引出四個相和兩個公共線（連接到正極）。一相接地。會被激發，。我們使用四相八拍控制，即第1階段第2階段交替反過來，會提高分辨率。步距角

58、0.9，可以轉移到控制電機勵磁是為了轉移如下：如果電機反轉的要求，傳輸的激勵信號可以逆轉的。 2控制方案控制系統框圖如下該方案采用AT89S51的主要控制裝置。它是與AT89C51兼容，但也增加了SPI接口和看門狗模塊，這不僅使調試變得更容易，也更穩定。單片機程序主要用于現場信號的采集和通過步進電機的運轉來計算的方向和速度信息。然后將信息發送到CPLD。CPLD使用EPM7128SLC84-15，ALTERA公司的MAX7000系列可編程邏輯器件EPM7128。具有高阻抗，電可擦除等特點，可用單位數為2500單位，工作電壓+5 V CPLD接收脈沖后轉換為相應的控制信號輸出到步進電機驅動器，從微控制器發送的信息。輸入后把控制信號發送到驅動電機繞組，以達到有效控制電機的目的。 2.1為電機驅動器的硬件結構電機驅動器通過下面的電路來實現：R1R8的電阻值為320。 R9-R12的電阻值為2.2K。 Q1Q4作為達林頓401A，Q5-Q8為S8550。