步进电机概述论文翻译英文版

外文文献：

Knowledge of the stepper motor

What is a stepper motor：

The stepping motor as executing components, electromechanical integration is one of the key products, widely used in a variety of automatic control systems. With the development of microelectronics and computer technology, the stepper motor demand grow with each passing day, has been applied in various fields of the national economy.

Stepping motor is a kind of electrical pulses into angular displacement of the implementing agencies. When stepping drive receives a pulse signal, it drives stepper motor rotate in the direction set by a fixed angle ( called the " step " ), it is the rotation at a fixed angle step by step operation. The number of pulses to control the amount of angular displacement through the control, so as to achieve the purpose of accurate positioning; also can control the pulse frequency to control motor rotation speed and acceleration, so as to achieve the purpose of speed. Special motor stepper motor control can be used as a, using its no accumulation of error ( accuracy of 100% ) characteristics, widely used in all kinds of open-loop control.

Now more commonly used step motor comprises stepper motor ( VR ), permanent magnet stepper motor ( PM ), hybrid stepping motor ( HB ) and single-phase stepping motor.

Permanent magnet stepper motor for general two-phase, torque and small volume, the step angle is 7.5 degree or 15 degree;

Reaction stepping motor is generally three-phase, can achieve a high torque output, step angle is 1.5 degrees, but the noise and vibration are great. The rotor magnetic circuit made of soft magnetic material reaction stepper motor, a multi-phase excitation winding stator, using magnetic torque changes.

Hybrid stepping motor is mixed the advantages of permanent magnet type and

reaction type. It is divided into two phase and five phase: two-phase stepper angle is 1.8 degree and five phase stepper angle is 0.72 degrees. Application of the stepping motor is the most widely, is also this subdivision driving of stepper motor selection scheme.

Some of the basic parameters of step motor:

The natural step motor:

It says every hair a step pulse signal control system, motor rotation angle. Motor factory is a step angle values, such as type 86BYG250A motor is given a value of 0.9°/1.8 °( said a half step of work is 0.9 °, the whole step of work is 1.8 °), this step can be called ' motor fixed step ', it doesn't have to be the actual motor work when the real step angle, angle and drive the real steps.

Stepper motor phase number:

Is the number of coils inside the motor, commonly used in a two-phase, three-phase, four phase, five phase stepper motor. The number of motor phase is different, the step angle is also different, the general two-phase motor step angle is 0.9°/1.8 °, three-phase 0.75 °/1.5 °, five phase of 0.36 °/0.72 °. In the absence of subdivision drive, users mainly rely on different phases of the stepper motor to meet their own requirements of step angle. If you use a subdivision driver, is ' phase ' will become meaningless, users only need to change the fine fraction in the drive, you can change the step angle.

Keep the torque ( HOLDINGTORQUE ):

Is the stepper motor power but there is no rotation, the stator locked rotor torque. It is one of the most important parameters of step motor, usually stepper motor in the low-speed torque to keep the torque. Because of the larger output torque stepper motor with speed and continuous decay, increases the output power with the speed of change, so keep the torque becomes one of the most important parameters of step motor. For example, when people say 2N.m stepper motor, in the absence of exceptional circumstances described in that refers to keep the torque

motor for the 2N.m step.

DETENTTORQUE:

DETENTTORQUE:

Refers to the stepper motor is not energized condition, the stator locked rotor torque. DETENTTORQUE does not have a unified way of translation in China, easy to make people misunderstand; as the rotor reaction stepper motor is not permanent magnetic material, so it has no DETENTTORQUE.

Some of the characteristic of step motor:

The 1 stepper motor step angle accuracy for 3-5%, and no accumulation.

2 stepper motor appearance allows the maximum temperature.

Stepper motor temperature is too high will first make the motor magnetic material demagnetization, resulting in lower torque and loss, so the highest temperature of motor appearance allows should depend on the different motor demagnetization magnetic materials; generally speaking, demagnetization point magnetic material in 130 degrees Celsius above, some even as high as 200 degrees Celsius stepping motor, so the surface temperature at 80-90 degrees Celsius completely normal.

3 stepper motor torque will decrease with the increase of rotational speed.

When the stepper motor rotates, the electrical inductance of the winding will form a reverse electromotive force; the higher the frequency, the greater the reverse emf. Under the influence of it, the motor with frequency ( or speed ) increase and the phase current is reduced, resulting in lower torque.

4 stepper motor speed can be normal operation, but if it is more than a certain speed will not start, and accompanied by howling.

Stepper motor is a technical parameter: no-load start frequency, namely the stepper motor under no-load condition can pulse frequency start, if the pulse

frequency is higher than the value, the motor can not start properly, may have lost step or stall. In under the condition of the load, start frequency should be less. If you want to enable the motor to rotate at high speed, pulse frequency should accelerate the process is started, the lower frequency, and then according to certain acceleration up to high frequency desired ( motor speed from low speed to high speed ).

Characteristics of stepper motor with its significant, play an important purpose in the era of digital manufacturing. With the different development of digital technology and stepper motor itself technology improves, the stepper motor will be applied in more fields.

How to determine the stepper motor driver DC power supply：

A. Determination of the voltage

Hybrid 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 motor 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 Current

Power supply current is generally based on the output phase current 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 be added operate pulse drive signal must be no pulse when the stepper motor at rest, such as

If 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 degrees, 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 core of the stepper motor as the driving force.

Stepper motor control example

We 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 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 requirements of motor reversal, the transmission excitation signal can be reversed. 2 control scheme

Control 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 makes 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 of large-scale, for the ALTERA company's 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 the 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 drive

Motor drive using the following circuit:

R1-R8 in which the resistance value of 320Ω. R9-R12 resistance value 2.2KΩ. Q1-Q4 as Darlington D401A, Q5-Q8 for the S8550. J1, J2 and the stepper motor connected to the six-lead。

Advantages and disadvantages of stepper motor

Advantages

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 time);

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 just 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 simple

System cost

7. Just load directly connected to the motor shaft can also be extremely slow synchronous rotation.

8. Speed is proportional to the pulse frequency, and thus a relatively wide speed range.

Shortcomings

1. If not properly controlled prone to resonance;

2. Difficult operation to a higher speed.

3. Difficult to obtain high torque

4. There is no advantage in terms of volume 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 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 control 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 connect 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 developments

Domestic and international research on the sub-drive technology is very 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, noise 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 change 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 AT89S51

Description

The AT89S51 is a low-power, high-performance CMOS 8-bit microcomputer

with 4K bytes of Flash programmable and erasable read only memory (PEROM). The device is manufactured using Atmel’s 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 conventional nonvolatile memory programmer. By combining a versatile 8-bit CPU with Flash on a monolithic chip, the Atmel AT89S51 is a powerful microcomputer which provides a highly-flexible and cost-effective solution to many embedded control applications.

Function characteristic

The AT89S51 provides the following 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 AT89S51 is designed with static logic for operation down to zero 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 until the next hardware reset. Pin Description

VCC：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 configured 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 programverification.

Port 1

Port 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 pulled 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 2

Port 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 written 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 during 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 address bits and some control signals during Flash programming and verification.

Port 3

Port 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 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 AT89S51 as listed below:

Port 3 also receives some control signals for Flash programming and verification.

RST

Reset input. A high on this pin for two machine cycles while the oscillator is running resets the device.

ALE/PROG

Address 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 normal 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 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.

PSEN

Program Store Enable is the read strobe to external program memory.When the AT89S51 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/VPP

External Access Enable. EA must be strapped to GND in order to enable the device to fetch code from external program 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 parts that require12-volt VPP.

XTAL1

Input to the inverting oscillator amplifier and input to the internal clock operating circuit.

XTAL2

Output from the inverting oscillator amplifier.

Oscillator Characteristics

XTAL1 and XTAL2 are the input and output, respectively,of an inverting amplifier which can be 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 the 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 Configuration

Idle Mode

In idle mode, the 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 should 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 pins 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 Mode

In the power-down mode, the oscillator is stopped, 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 RAM. 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.

概率论毕业论文外文翻译

Statistical hypothesis testing Adriana Albu，Loredana Ungureanu Politehnica University Timisoara,adrianaa@aut.utt.ro Politehnica University Timisoara,loredanau@aut.utt.ro Abstract In this article,we present a Bayesian statistical hypothesis testing inspection, testing theory and the process Mentioned hypothesis testing in the real world and the importance of, and successful test of the Notes. Key words Bayesian hypothesis testing; Bayesian inference;Test of significance Introduction A statistical hypothesis test is a method of making decisions using data, whether from a controlled experiment or an observational study (not controlled). In statistics, a result is called statistically significant if it is unlikely to have occurred by chance alone, according to a pre-determined threshold probability, the significance level. The phrase "test of significance" was coined by Ronald Fisher: "Critical tests of this kind may be called tests of significance, and when such tests are available we may discover whether a second sample is or is not significantly different from the first."[1] Hypothesis testing is sometimes called confirmatory data analysis, in contrast to exploratory data analysis. In frequency probability,these decisions are almost always made using null-hypothesis tests. These are tests that answer the question Assuming that the null hypothesis is true, what is the probability of observing a value for the test statistic that is at [] least as extreme as the value that was actually observed?) 2 More formally, they represent answers to the question, posed before undertaking an experiment,of what outcomes of the experiment would lead to rejection of the null hypothesis for a pre-specified probability of an incorrect rejection. One use of hypothesis testing is deciding whether experimental results contain enough information to cast doubt on conventional wisdom. Statistical hypothesis testing is a key technique of frequentist statistical inference. The Bayesian approach to hypothesis testing is to base rejection of the hypothesis on the posterior probability.[3][4]Other approaches to reaching a decision based on data are available via decision theory and optimal decisions. The critical region of a hypothesis test is the set of all outcomes which cause the null hypothesis to be rejected in favor of the alternative hypothesis. The critical region is usually denoted by the letter C. One-sample tests are appropriate when a sample is being compared to the population from a hypothesis. The population characteristics are known from theory or are calculated from the population.

步进电机的单片机控制外文翻译

附录2：英文资料及其中文翻译 Stepper motor is an electrical pulse will be converted into angular displacement of the implem enting agencies. Put it in simple language-speaking: When the stepper drive pulse signal to a r eceiver, it drives stepper motor rotation direction by setting a fixed point of view (and the ste p angle). You can control the number of pulses to control the amount of angular displacement, so as to achieve the purpose of accurate positioning; At the same time, you can by controllin g the pulse frequency to control the motor rotation speed and acceleration, so as to achieve th e purpose of speed. Stepper motor directly from the AC-DC power supply, and must use special equipment - stepp er motor drive. Stepper motor drive system performance, in addition to their own performance with the motor on the outside, but also to a large extent depend on the drive is good or bad. A typical stepper motor drive system is operated by the stepper motor controller, stepper mot or drives and stepper motor body is composed of three parts. Stepper motor controller stepper pulse and direction signal, each made of a pulse, stepper motor-driven stepper motor drives a rotor rotating step angle, that is, step-by-step further. High or low speed stepper motor, or spe ed, or deceleration, start or stop pulses are entirely dependent on whether the level or frequenc y. Decide the direction of the signal controller stepper motor clockwise or counterclockwise rot ation. Typically, the stepper motor drive circuit from the logic control, power driver circuit, pr otection circuit and power components. Stepper motor drive controller, once received from the direction of the signal and step pulse, the control circuit on a pre-determined way of the electr ical power-phase stepper motor excitation windings of the conduction or cut-off signal. Control circuit output signal power is low, can not provide the necessary stepping motor output powe r, the need for power amplifier, which is stepper motor driven power drive part. Power stepper motor drive circuit to control the input current winding to form a space for rotating magnetic field excitation, the rotor-driven movement. Protection circuit in the event of short circuit, ove rload, overheating, such as failure to stop the rapid drive and motor. Motor is usually for the permanent magnet rotor, when the current flows through the stator wi ndings, the stator windings produce a magnetic field vector. The magnetic field will lead to a rotor angle of rotation, making a pair of rotor and stator magnetic field direction of the magne tic field direction. When the stator rotating magnetic field vector from a different angle. Also as the rotor magnetic field to a point of view. An electrical pulse for each input, the motor r otation angle step. Its output and input of the angular displacement is proportional to the pulse s, with pulse frequency proportional to speed. Power to change the order of winding, the elect rical will be reversed. We can, therefore, control the pulse number, frequency and electrical po wer windings of each phase to control the order of rotation of stepper motor. Stepper motor types: Permanent magnet (PM). Magnetic generally two-phase stepper, torque and are smaller and gen erally stepping angle of 7.5 degrees or 15 degrees; put more wind for air-conditioning. Reactive (VR), the domestic general called BF, have a common three-phase reaction, step angl e of 1.5 degrees; also have five-phase reaction. Noise, no torque has been set at a large numb er of out. Hybrid (HB), common two-phase hybrid, five-phase hybrid, three-phase hybrid, four-phase hybri d, two-phase can be common with the four-phase drive, five-phase three-phase must be used w ith their drives;

毕业论文外文翻译模版

吉林化工学院理学院 毕业论文外文翻译English Title（Times New Roman ，三号） 学生学号：08810219 学生姓名：袁庚文 专业班级：信息与计算科学0802 指导教师：赵瑛 职称副教授 起止日期：2012.2.27～2012.3.14 吉林化工学院 Jilin Institute of Chemical Technology

1 外文翻译的基本内容 应选择与本课题密切相关的外文文献（学术期刊网上的），译成中文，与原文装订在一起并独立成册。在毕业答辩前，同论文一起上交。译文字数不应少于3000个汉字。 2 书写规范 2.1 外文翻译的正文格式 正文版心设置为：上边距：3.5厘米，下边距：2.5厘米，左边距：3.5厘米，右边距：2厘米，页眉：2.5厘米，页脚：2厘米。 中文部分正文选用模板中的样式所定义的“正文”，每段落首行缩进2字；或者手动设置成每段落首行缩进2字，字体：宋体，字号：小四，行距：多倍行距1.3，间距：前段、后段均为0行。 这部分工作模板中已经自动设置为缺省值。 2.2标题格式 特别注意：各级标题的具体形式可参照外文原文确定。 1．第一级标题（如：第1章绪论）选用模板中的样式所定义的“标题1”，居左；或者手动设置成字体：黑体，居左，字号：三号，1.5倍行距，段后11磅，段前为11磅。 2．第二级标题（如：1.2 摘要与关键词）选用模板中的样式所定义的“标题2”，居左；或者手动设置成字体：黑体，居左，字号：四号，1.5倍行距，段后为0，段前0.5行。 3．第三级标题（如：1.2.1 摘要）选用模板中的样式所定义的“标题3”，居左；或者手动设置成字体：黑体，居左，字号：小四，1.5倍行距，段后为0，段前0.5行。 标题和后面文字之间空一格（半角）。 3 图表及公式等的格式说明 图表、公式、参考文献等的格式详见《吉林化工学院本科学生毕业设计说明书（论文）撰写规范及标准模版》中相关的说明。

基于单片机的步进电机控制系统设计外文翻译

毕业设计(论文)外文资料翻译 学院：机械工程学院 专业：机械设计制造及其自动化 姓名： 学号：XXXXXXXXXX 外文出处：《Computational Intelligence and (用外文写)Design》 附件： 1.外文资料翻译译文；2.外文原文。 注：请将该封面与附件装订成册。

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