1、 本科生毕业设计（论文）专业外文翻译原 文： Frequency Variation Speed Control 译 文： 变 频 技 术 指导教师 ： 职称： 讲师 学生姓名 ： 学号：1002120340 专 业 ： 电气工程及其自动化 院（系） ： 机电工程学院 2014年 3月 20日Frequency Variation Speed ControlThe Popularity and Prospect of Frequency Variation Speed ControlThe electrical machinery exchange frequency conversion v
2、elocity modulation technology is the electricity saving, the improvement technical process improves the product quality and the improvement environment, the impetus technology advancement one main method now The frequency conversion velocity modulation by its outstanding velocity modulation and the
3、braking quality, the high efficiency, the high power factor and the electricity saving effect, the widespread applicable scope and other many merits by the domestic grandfather was thought most has the development future velocity modulation way. The electrical transmission control system usually by
4、the electric motor, the control device and the information installs 3 parts to be composed, the electrical transmission relates uses the electric motor by to save the electrical energy and to control the machinery reasonably the operating condition, the realization electrical energy - mechanical ene
5、rgy transformation, achieves, the high production, the low consumption goal high quality. The electrical transmission divides into does not modulate velocity and modulates velocity two big kinds, the velocity modulation is divided the exchange to modulate velocity and to direct current modulates vel
6、ocity two ways. The variable speed motor directly does not supply power by the electrical network But the machinery which does not modulate velocity along with electric power electronic technology development this kind of original manuscript more and more many changes to the velocity modulation tran
7、smission by to save the electrical energy The improvement product quality, enhances the output Therefore the velocity modulation transmission is an important profession, already obtained the country to take, at present had certain scale.In recent years exchanged in the velocity modulation most to be
8、 active, to develop quickest is the frequency conversion velocity modulation technology, the frequency conversion velocity modulation is exchanges the velocity modulation foundation and the branch content. The last century transformer appearance causes the change voltage to become very much easy, th
9、us has accomplished a huge electric power profession. Since long ago, the alternating current frequency always is fixed, the frequency conversion velocity modulation technology appearance causes the frequency to become may the full use resources.In this recent 10 years, the frequency conversion tech
10、nology application has the very big development in our country, and obtained the good effect to be possible to say, the frequency conversion technology has accepted for the majority users, but had no alternative but to point out, our country in frequency conversion technology application aspect, wit
11、h developed country level Shang You very big disparity. At present, the AC motors we are using now use frequency variation speed control only about 6%, but the developed country is 60%70%, Japan on air blower, water pump frequency conversion velocity modulation use rate is 10%, but our country is le
12、ss than 0.01%, In Japan air-conditioner using frequency variation technique rate is 70%, but our countrys only then just started Embarks from this reality, frequency conversion technology remain have the very big development space, we should complete the promoted application work doggedly.And with t
13、he constant development of control technique and control avenue, frequency variation speed controlled has developed the vector controlled frequency variation velocity modulation, by controlling the AC motor inside act for shunt DC motor field copers flux, to enhance the permanent torque output scope
14、 and static and dynamic character, make the AC motor frequency variation speed controlled system superior to DC motor voltage variation speed controlled system. For simplifying the control system, reducing the fault rate, there has developed a vector controlled frequency variation speed control with
15、out speed sensor which based on the vector controlled frequency variation speed control. In some application which have low require , vector controlled frequency variation speed control without speed sensor could completely compare with the vector controlled frequency variation speed control that ha
16、ve speed sensor. The vector control has the epoch-making significance to the AC current motor velocity modulation.Frequency variation speed control is the best way in the motor speed modulation, it is the perfect gear in the companys technical reform and product renewal, it is the essential composit
17、ion in the industrial automatic system, it is the assumption of realizing the automatic of product proceed and management, it is also the precondition in the development of informationization. In our countrys traditional estate, using the DC motor speed control actuation account about 85%90% in the
18、speed controlled system, but the AC speed controlled system account about 10%15%. Low efficiency, bad quality, large cost, high fault rate have already been the bottleneck that restrain the development of the company. So, we must promote the advanced AC frequency variation speed control technique po
19、sitively, arms the traditional industry with the advanced equipment, promote a further development in the automation, the industrialization and the informationization.Our Countrys Development Condition in Speed Controlled TechniqueOur country is a developing country, so many products research abilit
20、y has behind the developed countries. From now on, the product of frequency variation speed controlled that ourselves made only act for last century 90s in the international. With the reform and opening, rapid development of economic, forms a large market, it opens to the country companies, also the
21、 foreign companies. Many products are exported from the developed countries, and runs well in our country, satisfied our need in fabrication and living. Many co-partership companies in our country make the international advanced products. The domestic complete department independently is designing t
22、he manufacture in the complete set installment to use the foreign import company and the joint venture supposes advanced each, own develop the application software, can provide the first-class electrical transmission control system for the domestic and foreign important engineering project. Although
23、 obtains very many result, but should see because domestic develops, the production product ability voluntarily is weak, is serious to the overseas companys dependence.As early as in the country “85“ technical attack plan, the alternating velocity modulation technique was listed as the key technical
24、 attack project, but because our countrys electric power and electronic device aggregate level is very low, although the production of IGBT、GTO component has introduced the overseas technique, it has not formed the economies of scale benefit, almost does not have the independent development ability
25、of new frequency converter production, this has affected the domestic frequency conversion velocity modulation technique development in the certain degree. In the high efficiency AC-AC frequency convert technique、the motors without commutator technique and so on, the domestic product also has the su
26、itable disparity in the digitization and the system reliable aspect compares with the overseas level, in the medium efficiency frequency convert technique, nearly all productions use ordinary V/F control inland, few adopt the vector control technique, and can not satisfied the market requirement in
27、the variety and quality. But in overseas, the frequency conversion technique obtains the full development, and has obtained the remarkable achievement in each aspect. In power component aspect, high voltage、the appearance of SCR、GTO、IGBT、IGCT with high current capacity and the using in series and pa
28、rallel, the high-pressured and high efficiency frequency converter production obtains the production and the promoted application. In microelectronic technique aspect, 16bit and 32bit high speed microprocessors as well as the fast development of DSP and ASIC technique, provided the hardware method i
29、n realizing the frequency converter which with high accuracy multi-purpose. In theory aspect, the vector control, the magnetic flux control, the torque control, the intelligent control, the new control theory and so on have provided the related rationale for the high performance frequency converter
30、development, we may see that, in the overall, the alternating frequency conversion velocity modulation technique in our country has big disparity compares with international level.Therefore, the AC frequency variation speed control technique has the following sides:1) The basic research of control s
31、trategy in frequency converter has a large gap compares with the foreign level.2) The technical level of the whole machine is low in the frequency converter, although we had input certainly people, material resources, but because of the disperse power, did not form a certainly technique and producti
32、on scale.3) All the semiconductor power device product in the frequency converter is blank.4) Correlative Industries and relative Industries drop behind.5) Few production and sale, low reliable and technological standards.With the development and improvement in the power electronic technique, power
33、divert based on power electronic circuit technique and various control technique, the AC frequency variation speed controlled technique is mature day by day, and sure to be the main way in the future. With the constant development of power electronic technique, reliable character, well adoption, che
34、ap price that the frequency converter have will become true. This technique will gain widely, popularity application .At present, foreign developed countries frequency convert technique towards to the miniaturization, high reliability, defend with harm, more function, high character, and our country
35、 is coming on now.Frequency Variation Speed Controlled ModeThe alternating frequency conversion velocity modulation technique obtained the rapid development in 20th century. This is related with some crucial technical which gain unprecedented progress, they are Motor vector control technique, Direct
36、 torque control technique, PWM technique, Entire numerical control technique and self-setting technique which based on microcomputer and large scale integrated circuit, and so on.1) Vector Control TechniqueVector transformation control technique is a one kind of new control thought and control theor
37、y which posed by SIEMENS CO. in 1971. It is realizing the stator current excitation component and the torque component solution lotus root by rotor magnetic field direction detection, and vector transformation, achieved the goal that separately control the motor flux linkage and the electric current
38、, as a result, obtain finely static, dynamic performance. Until now, the vector control technique has obtained the considerable development, and also obtained the widespread application.2) Vector Control Without Velocity Generator TechniqueVector control without velocity generator technique abolish
39、the problems that the environment compatibility、install and maintenance bring on, reduce the cost, enhance the system reliability, at the same time, union vector control, has the fine performance of vector control. The speed estimate method in vector control technique without velocity generator, bes
40、ides basis mathematical model computation electric motor rotational speed, at present the more applied are the model to refer auto-adapted method and expands the Kalman filtering law. In addition, entire Uygur rotor magnetic flux sight, tooth overtone electric potential, such as this theory and so o
41、n, also appearance in the vector control without velocity generator technique. Since 1983 proposed the vector control without velocity generator technique control strategy, receives the academic circles and the industrial field continuously highly focused all the time. Hitachi company and Sichuan el
42、ectrical machinery and so on had published the research results separately in 1987, and had promoted the product one after another. At present, vector control without velocity generator technique in frequency converter controlling in the velocity modulation scope is about 1:50, some individual merch
43、ant has 1:75 or even higher product.3) Direct Torque Control TechniqueIn1985, Germanys M. Depen-block proposes the direct torque control technique（DTC ） for the first time，The direct torque control technique analyzes the motor mathematical model directly under the stator coordinate system. Uses the
44、stator magnetic field direction detection but not to need the solution lotus root electric current，directly control the electric motor flux linkage and torque, enable the torque to obtain the fast response, in order to obtain the highly effective control performance.Direct torque control technique i
45、s another kind of new、high performance alternating frequency conversion velocity modulation technique after vector control technique in the nearly 10 years, this kind of control technique is insensitive to the electrical machinery parameter, not influence by the rotor parameter, easy and feasible, i
46、t has the broad development and the application prospect.4) PWM (pulse width modulation) Control TechniqueIn1964, Germanys A. Schonung and some people took the lead to propose the pulse-duration modulation (PWM -pulse width modulation) frequency conversion thought, opened the recent development doma
47、in for the modern alternating velocity modulation system. The PWM control technique controls the inversion output alternating fundamental wave voltage peak-to-peak value by changing the rectangle pulse width, controls its output frequency through changing the modulation cycle, in order to carry on t
48、he output voltage peak-to-peak value and the frequency control on the inversion at the same time. The PWM technique simplified the inversion structure, can distinctly change the output wave shape of the frequency converter, reduces the overtone loss of electric motor, and reduces the torque pulsatio
49、n, at the same time enhances the performance of dynamic response system. The PWM technique also may use in the rectifier controlling, can realize the input current which approaches the sine extremely. And may cause the electrical network power factor is 1. The PWM rectifier thus is called “the green converter”. At present, PWM technique has become the most widespread control technique applied in the frequency converter. The unceasingly velocity modulation performance of alternating c
