电气专业英语论文
关于电气工程专业英语的作文
关于电气工程专业英语的作文Diving into the realm of electrical engineering is like exploring a vast, intricate web of innovation and technology that powers our modern world. This field, with its heart set on the pulse of progress, is not just about circuits and currents; it's a language of its own, with English at its core, bridging the gap between theory and application.Electrical engineering is a discipline that has evolved dramatically over the decades, and its language has kept pace, incorporating a rich lexicon of terms that describeeverything from the most fundamental components to the most cutting-edge technologies. For students and professionals alike, mastering the English terminology is crucial for understanding the principles that underpin electrical systems, from the microchip to the power grid.In this dynamic field, the ability to communicate effectively in English is paramount. Whether it's discussing the intricacies of a power electronics converter or thedesign of a high-voltage transmission line, precision in language is as important as precision in engineering. English serves as the universal medium for scholarly articles, technical specifications, and international conferences,where the latest research and developments are shared.Moreover, the language of electrical engineering is not static; it evolves with the field. New terms emerge astechnologies advance, such as "smart grid," "renewable energy," and "Internet of Things (IoT)," each reflecting the ongoing expansion of the discipline. Keeping up with these developments requires a commitment to continuous learning and an openness to embracing new concepts and terminologies.The study of electrical engineering English also extends beyond the technical. It encompasses the ability to interpret and create diagrams, to understand and apply mathematical models, and to engage in critical thinking about the implications of new technologies on society and the environment.In essence, the mastery of electrical engineering English is not just about the words; it's about the ideas they represent and the solutions they enable. It's about theability to connect with a global community of engineers, to contribute to a field that is constantly pushing the boundaries of what is possible, and to be part of a conversation that shapes the future of our world.。
有关电气专业的英语作文
有关电气专业的英语作文I have always been fascinated by electricity and how it powers the world around us. The ability to manipulate and control the flow of electrons is truly amazing.When I first started studying electrical engineering, I was overwhelmed by the amount of knowledge and information I needed to absorb. However, as I delved deeper into the subject, I found myself becoming more and more passionate about it.One of the most exciting things about electrical engineering is the endless possibilities it offers. From designing circuits to working on power systems, there is always something new and challenging to explore.I love the hands-on aspect of electrical engineering. There is something incredibly satisfying about building and testing circuits, and seeing the results of your work come to life.The field of electrical engineering is constantly evolving, and it is crucial to stay updated with the latest technologies and advancements. This constant learning and adaptation keep the profession exciting and dynamic.The problem-solving aspect of electrical engineering is what drew me to the field in the first place. I enjoy the challenge of identifying and solving complex electrical issues, and the sense of accomplishment that comes with finding a solution.The impact of electrical engineering on the world is undeniable. From powering homes and businesses to driving technological innovations, electrical engineers play a crucial role in shaping the modern world.In conclusion, electrical engineering is a diverse and dynamic field that offers endless opportunities for learning and growth. I am excited to continue my journey in this field and see where it takes me.。
电气专业的英语作文
电气专业的英语作文In the heart of technological advancement lies the field of electrical engineering, a discipline that has been pivotal in shaping our modern society. This essay will explore the importance of electrical engineering, its applications, andits impact on various sectors.First and foremost, electrical engineering is the backbone of modern communication systems. The development of wireless technologies, such as Wi-Fi and cellular networks, has been made possible through the expertise of electrical engineers. These technologies have revolutionized the way we communicate, allowing for instant messaging, video calls, and the seamless sharing of information across the globe.Moreover, the field has played a crucial role in the advancement of renewable energy sources. Solar panels, wind turbines, and other forms of green energy rely heavily on electrical engineering to convert, distribute, and manage the energy they produce. This has led to a significant reductionin our reliance on fossil fuels, contributing to a cleanerand more sustainable future.In the medical sector, electrical engineering has also made a profound impact. Medical imaging technologies, such as MRIand CT scans, rely on complex electrical systems to function. These systems are essential for diagnosing and treating awide range of medical conditions, thereby improving patientoutcomes and saving lives.Furthermore, the automotive industry has been transformed by the integration of electrical engineering. Electric vehicles (EVs) are becoming increasingly popular due to their environmental benefits and efficiency. The design and production of EVs require a deep understanding of electrical systems, batteries, and power management, all of which are at the core of electrical engineering.Lastly, the field of electrical engineering is integral to the development of smart cities. Smart grids, intelligent transportation systems, and automated infrastructure are all dependent on sophisticated electrical systems. These systems are designed to optimize energy use, reduce waste, and improve the overall quality of life for city dwellers.In conclusion, electrical engineering is a multifaceted discipline that has a profound impact on various aspects of modern society. From communication to renewable energy, medical technology to transportation, and smart city development, the role of electrical engineering is indispensable. As we continue to innovate and push the boundaries of technology, the importance of this field will only continue to grow.。
电气工程及其自动化专业英语作文范文
电气工程及其自动化专业英语作文范文Electrical Engineering and Automation: An Integral Part of Modern SocietyIntroductionElectrical Engineering and Automation, a discipline that has evolved significantly over the past few decades, has become an integral part of modern society. Its widespread applications in industry, agriculture, national defense, and various other fields have propelled it to a pivotal position in the global economy.Historical PerspectiveThe field of Electrical Engineering and Automation was first established approximately forty years ago. As a relatively new discipline, it has quickly grown to encompass a wide range of subfields and applications. From the design of switches for aerospace aircraft to the development of complex automated systems, its influence is pervasive.Core ComponentsThe core of Electrical Engineering and Automation lies in its ability to integrate electricity, machines, and intelligent systems to automate various tasks. This integration enables efficiency, precision, and safety in a wide range of applications.•Electricity and Machines: Electricity provides the power that drives machines and systems. Understanding the behavior ofelectrical circuits, voltage sources, current sources, andvarious network elements is crucial for the effective designand operation of automated systems.•Automation: Automation refers to the use of technology to control and monitor processes and machines with minimal humanintervention. It relies on sensors, actuators, and intelligentcontrollers to achieve desired outcomes.Challenges and OpportunitiesWhile Electrical Engineering and Automation offers immense opportunities for growth and development, it also poses significantchallenges. The complexity of modern systems requires a high level of technical knowledge and expertise. Additionally, the rapid pace of technological advancement requires constant updating of skills and knowledge.However, these challenges also present opportunities for innovation and growth. As new technologies emerge, there is a need for engineers and technicians who can understand and apply them effectively. This creates opportunities for those with a passion for learning and a willingness to adapt to new challenges.ConclusionIn conclusion, Electrical Engineering and Automation is a dynamic and exciting field that offers immense opportunities for growth and development. Its applications are pervasive, and its influence on society is profound. As we continue to push the boundaries of technology, Electrical Engineering and Automation will play an increasingly important role in shaping our future.。
电气工程及其自动化专业英语课程论文完整版
电气工程及其自动化专业英语课程论文Document serial number【NL89WT-NY98YT-NC8CB-NNUUT-NUT108】重庆邮电大学移通学院《电气工程及其自动化专业英语》课程论文年级 2012专业电气工程与自动化姓名孙猜胜学号Three-phase asynchronous motorAbstract:The three-phase asynchronous motor is motor's one with single phase asynchronous motor, three-phase asynchronous motor operating performance is good, and can save various the structure to be simple, the manufacture is easy, firm durable, the service is convenient,cost inexpensive ,drag the ability is good,and so on a series of merits. thus becomes in each kind of electrical machinery the outputto be biggest utilizes the broadest one kind of electric motor.Key words:Moror Motor starting Star delta StartingThree-phase asynchronous motor principle:When the stator winding through into the three-phase ac three-phase symmetric arises when a synchronous speed n1 along the stator and rotor round for space in a clockwise rotation magnetic field. Because of a rotating magnetic field rotating speed to n1, rotor conductor of the static beginning, so the rotor conductor will cutthe stator and produce a rotating magnetic field induction emf (induction emf direction DingZe judge with the right hand). Because the child is short circuit loop ends conductor short meet, in therole of the induced emf, will produce the rotor conductor with induction emf direction basic consistent induced current. The rotor current-carrying conductor at stator magnetic field is the role ofthe electromagnetic force (the direction of the force with the left hand DingZe judge). The electromagnetic force of the rotor axis electromagnetic torque, drive along the rotor rotating magnetic field rotation direction.[1]Through the above analysis can be summed up the motor principle: when the three-phase motor stator winding (eachdiffer 120 KWH Angle), ventilation with three-phase ac, will producea rotating magnetic field, the rotating magnetic field cutting rotor winding, and thus to the rotor winding induced current (rotor windingis closed access), load flow of rotor stator conductor under the action of a rotating magnetic field will produce the electromagnetic force, thus in the motor shaft formed on the electromagnetic torque, driving motor rotation, and motor rotation direction and the rotating magnetic field in the same direction.Thestructureofthree-phaseasynchronousmotor:Types of three-phase asynchronous motor, but all kinds of three-phase asynchronous motor is the same basic structure, they are the stator and rotor of these two basic components, the stator and rotor has a certain air gap between. In addition, end caps, bearings, cable boxes, rings and other accessories,1).StatorpartStator is used to generate the rotating magnetic Three-phase motors generally shell, stator core, stator windings and other parts.a.Shell?Three-phase motor casing including base,end caps,bearingcaps,rings,such as junction boxes and comp onentsb. Stator CoreInduction motor stator core is part of the motor circuit from ~ thick coated with a thin insulating paint from silicon,c.ThestatorwindingsThree-phase motor stator windings are part of the circuit,there are three-phase three-phase motor windings,summetrical three-phase current access,it will have a rotating magnetic winding consists of three separate components of the winding, and each has a number of coil windings a phase of each winding, each winding in the space angle difference between the 120 ° electrical[2].2). Rotor parta. Rotor CoreWith mm thick steel from, set in the shaft, the role and the same stator core, on the one hand, as part of the motor magnetic circuit, on the one hand to place the rotor windings.b. Rotor windingsThe rotor winding induction motor winding is divided into two kinds of cage-shaped and which is divided into winding rotor asynchronous motor with cage induction motor.3). Other parts ofOther parts including the cover, fans, etc.Induction motor starting methods:There are several general methods of starting induction motors: full voltage, reduced voltage,wyes-delta,and part winding reduced voltage type can include solid state starters, adjustable frequency drives, and following is the most common method.1).Full voltageThe full voltage starting method, also known as across the line starting, is the easiest method to employ, has the lowest equipment costs, and is the most reliable. This method utilizes a control to close a contactor and apply full line voltage to the motor terminals. This method will allow the motor to generate its highest starting torque and provide the shortest acceleration method also puts the highest strain on the power system due to the high starting currents that can be typically six to seven times the normal full load current of the motor.2).AutotransformerThe motor leads are connected to the lower voltage side of the transformer. The most common taps that are used are 80%, 65%, and 50%. At 50% voltage the current on the primary is 25% of the full voltage locked rotor amps. The motor is started with this reduced voltage,and then after a pre-set condition is reached the connection is switched to line voltage. This condition could be a preset time, current level, bus volts, or motor speed. The change over can be done in either a closed circuit transition, or an open circuit transition method. In the open circuit method the connection to the voltage is severed as it is changed from the reduced voltage to the line level. Care should be used to make sure that there will not be problems from transients due to the switching. This potential problem can be eliminated by using the closed circuit transition. With the closed circuit method there is a continuous Voltage applied to the motor. Another benefit with the autotransformer starting is in possiblelower vibration and noise levels during starting.3).Star delta StartingThis approach started with the induction motor,the structure of each phase of the terminal are placed in the motor teminal box ,This allows the motor star connection in the initial start up,and then re-connected into a triangle run..The initial start time when the voltage is reduced to the original star connection,the startingcurrent and starting torque by 2/3. Depending on the applicationon,the motor switch to the triangle in the rotational speed of between 50% and the maximum be noted that the sameproblems,including the previously mentioned switch method ,if theopen circuit method,the transition may be a transient method isoften used in lesst than 600V motor,the rated voltage and higher are not suitable for star delta motor start method.[3]4).Series Resistor or Reactor StartingThis method is to use a series resistance or place in the motor loop the motor is started, a resistor to limit current and make the motor at the input voltage drop. Therefore plays a role of limitingcurrent at the small motor series resistor startup mode used more frequentlyConclusion:There are many ways asynchronous motor starting, each method hasits own benefits, according to the constraints of powersystems,equipment costs, load the boot device to select the best method.References:[1] Tang Tianhao Fundamentals of Electrical Machines and Drives [M] BeijingChina Machine Press 118-137[2] Wang Liming English for Electrical Engineering and Automation [M] BeijingTsinghua University Press 61-64[3] Stephen Electromechanics [M] America Electronic IndustryPress 340-370。
(完整word版)电气工程及其自动化专业外语作文
(完整word版)电气工程及其自动化专业外语作文A s a student, you will learn to apply related subjects such as computer technology，industrial electronics, instrumentation，electrical machines, robotics，power electronics，and automated control systems.作为一名学生，你将学会运用相关学科,如计算机技术，工业电子，仪器仪表，电器机械，机器人技术，电力电子和自动化控制系统。
Y ou will be able to understand written and oral instructions，as well as design, install, test，modify, troubleshoot，and repair electrical systems.您将能够理解书面和口头说明，以及设计,安装，测试，修改，故障排除和修复电力系统.U pon graduation，students of the Electrical Engineering Technology –Process Automation program can approach industrial electrical and electronic systems from the viewpoint of analysis，technical evaluation, design, and development。
The six—semester program concentrates on the in-depth study of electrical and electronic principles as they apply to automated systems using programmable logic controllers。
电气专业英语论文
院（系、部、中心）专业班级学生姓名学号任课教师Page1 Generators and Motors(发电机和电动机)1 English textFrom reference 11. Direct-current generators impress on the line a direct or continuous emf, one that is always in the same direction. Commercial dc generators have commutators, which distinguish them from ac generators. The function of a commutator and the elementary ideas of generation of emf and commutation are discussed in Div. 1. Additional information about commutation as applied to dc motors, which in general is true for dc generators, is given below.2. Excitation of generator fields. To generate an emf, conductors must cut a magnetic field which in commercial machines must be relatively strong. A permanent magnet can be used for producing such a field in a generator of small output, such as a telephone magneto or the magneto of an insulation tester, but in generators for light and power the field is produced by electromagnets, which may be excited by the machine itself or be separately excited from another source.Self-excited machines may be of the series, shunt, or compound type, depending upon the manner of connecting the field winding to the armature. In the series type of machine,the field winding (the winding which produces the magnetic field) is connected in series with the armature winding. In the shunt type, the field winding is connected inparallel,shunt, with the armature winding. Compound machines have two field windings on each pole. One of these windings is connected in series with the armature winding, and the other is connected in parallel or shunt with the armature winding.3. Armature winding of dc machines may be of the lap or the wave type. The difference in the two types is in the manner of connecting the armature coils to the commutator.A coil is the portion of the armature winding between successive connections to the commutator.In the lap type of winding (see Fig. 7.1) the two ends of a coil are connected to adjacent commutator segments. In the wave type of winding(see Fig. 7.2) the two ends of a coil are connected to commutator segments that are displaced from each other by approximately 360 electrical degrees.The type of armature winding employed affects the voltage and current capacity of the machine but has no effect upon the power capacity. This is due to the fact that the number of parallel paths between armature terminals is affected by the type of winding. For a wavewound machine there are always two paths in parallel in the armature winding between armature terminals. For a lap-wound machine there are as many parallel paths in the armature winding as there are pairs of poles on the machine. For the same number and size of armature conductors, a machine when wave-connected would generate a voltage that would equal the voltage generated when lap-connected times the number of pairs of poles.But the current capacity would be decreased in the same proportion that the voltage was increased. The current capacity of a machine when wave-connected is therefore equal to the capacity when lap-connected divided by the number of pairs of poles.4. The value of the voltage generated by a dc machine depends upon the armature winding, the speed, and the field current. For a given machine, therefore, the voltage generated can be controlled by adjusting either the speed or the field current. Since generators are usually operated at a constant speed, the voltage must be controlled by adjusting the field current.5. Separately excited dc generators are used for electroplating and for other electrolytic work for which the polarity of a machine must not be reversed.Self-excited machines may change their polarities. The essential diagrams are shown in Fig. 7.3. The fields can be excited from any dc constant-potential source, such as a storage battery, or from a rectifier connected to an ac supply.The field magnets can be wound for any voltage because they have no electric connection with the armature. With a constant field excitation, the voltage will drop slightly fromno load to full load because of armature drop and armature reaction.Separate excitation is advantageous when the voltage generated by the machine is not suitable for field excitation. This is true for especially low- or high-voltage machines.6. Series-wound generators have their armature winding, field coils, andexternal circuit connected in series with each other so that the same current flows through all parts of the circuit (see Fig. 7.4). If a series generator is operated at no load (external circuit open), there will be no current through the field coils, and the only magnetic flux presentin the machine will be that due to the residual magnetism which has been retained by the poles from previous operation. Therefore, the no-load voltage of a series generator will be only a few volts produced by cutting the residual flux. If the external circuit is closed and the current increased, the voltage will increase with the increase in current until the magnetic circuit becomes saturated. With any further increases of load the voltage will decrease. Series generators have been used sometimes in street-railway service. They have been connected in series with long trolley feeders supplying sections of the system distant from the supply point in order to boost the voltage. However, power rectifiers have replaced dc generators for most installations of this type.Keywords: generatorFrom reference 2Since triphased asynchronous generators are mainly used in conversion systems of a eolian energy into electric energy, their functional stability represent isof great importance. As a first step, the factors that radically affect the functional stability of these generators have been established. Thus, it was decelat the powerful influence of the capacitor bank – that provides the necessary reactive power for the magnetization of the ferromagnetic core – over the functional stability of the triphased asynchronous generator with short circuit rotor. The functional stability is greatly influenced by the charge character (type) as well. The experimental work emphasized – through the functional features – the way these parameters influence the stability area of the asynchronous generators. As far as triphased asynchronous generators with coiled rotor are concerned, the controllable blind power was analyzed the analogy being made with the situation of the necessary controllable generating capacity for of the triphased asynchronous generator with short circuit rotor.Keywords : triphased asynchronous generator.2 中文翻译及分析出资文献 1：1。
(完整版)电气专业中英文对照翻译毕业设计论文
优秀论文审核通过未经允许切勿外传Chapter 3 Digital Electronics3.1 IntroductionA circuit that employs a numerical signal in its operation is classified as a digital circuitputers,pocket calculators, digital instruments, and numerical control (NC) equipment are common applications of digital circuits. Practically unlimited quantities of digital information can be processed in short periods of time electronically. With operational speed of prime importance in electronics today,digital circuits are used more frequently.In this chapter, digital circuit applications are discussed.There are many types of digital circuits that electronics, including logic circuits, flip-flop circuits, counting circuits, and many others. The first sections of this unit discuss the number systems that are basic to digital circuit understanding. The remainder of the chapter introduces some of the types of digital circuits and explains Boolean algebra as it is applied to logic circuits.3.2 Digital Number SystemsThe most common number system used today is the decimal system,in which 10 digits are used for counting. The number of digits in the systemis called its base (or radix).The decimal system，therefore，the counting process. The largest digit that can be used in a specific place or location is determined by the base of the system. In the decimal system the first position to the left of the decimal point is called the units place. Any digit from 0 to 9 can be used in this place.When number values greater than 9 are used,they must be expressed with two or more places.The next position to the left of the units place in a decimal system is the tens place.The number 99 is the largest digital value that can be expressed by two places in the decimal system.Each place added to the left extends the number system by a power of 10.Any number can be expressed as a sum of weighted place values.The decimal number 2583,for example, is expressed as (2×1000)+(5×100)+(8×10)+(3×1).The decimal number system is commonly used in our daily lives. Electronically, the binary system.Electronically,the value of 0 can be associated with a low-voltage value or no voltage. The number 1 can then be associated with a voltage value larger than 0. Binary systems that use these voltage values are said to , this chapter.The two operational states of a binary system,1 and 0,are natural circuit conditions. When a circuit is turned off or the off, or 0,state. An electrical circuit that the on，or 1,state. By using transistor or ICs，it is electronically possible to change states in less than a microsecond. Electronic devices make it possible to manipulate millions of 0s and is in a second and thus to process information quickly.The basic principles of numbering used in decimal numbers apply ingeneral to binary numbers.The base of the binary system is 2,meaning that only the digits 0 and 1 are used to express place value. The first place to the left of the binary point,or starting point，represents the units，or is,location. Places to the left of the binary point are the powers of 2.Some of the place values in base 2 are 2º=1,2¹=2,2²=4,2³=8,2⁴=16,25=32,and 26=64.When bases other than 10 are used,the numbers should example.The number 100₂(read“one,zero,zero, base 2”)is equivalent to 4 in base 10,or 410.Starting with the first digit to the left of the binary point,this number this method of conversion a binary number to an equivalent decimal number，write down the binary number first. Starting at the binary point，indicate the decimal equivalent for each binary place location where a 1 is indicated. For each 0 in the binary number leave a blank space or indicate a 0 ' Add the place values and then record the decimal equivalent.The conversion of a decimal number to a binary equivalent is achieved by repetitive steps of division by the number 2.When the quotient is even with no remainder,a 0 is recorded.When the quotient process continues until the quotient is 0.The binary equivalent consists of the remainder values in the order last to first.3.2.2 Binary-coded Decimal (BCD) Number SystemWhen large numbers are indicated by binary numbers，they are difficult to use. For this reason，the Binary-Coded Decimal(BCD) method of counting was devised. In this system four binary digits are used to represent each decimal digit.To illustrate this procedure，the number 105，is converted to a BCD number.In binary numbers，To apply the BCD conversion process，the base 10 number is first divided into digits according to place values.The number 10510 gives the digits 1-0-5.Converting each displayed by this process with only 12 binary numbers. The between each group of digits is important when displaying BCD numbers.The largest digit to be displayed by any group of BCD numbers is 9.Six digits of a number-coding group are not used at all in this system.Because of this, the octal (base 8) and the binary form but usually display them in BCD,octal,or a base 8 system is 7. The place values starting at the left of the octal point are the powers of eight: 80=1,81=8,82=64,83=512,84=4096,and so on.The process of converting an octal number to a decimal number is the same as that used in the binary-to-decimal conversion process. In this method, equivalent decimal is 25810.Converting an octal number to an equivalent binary number is similar to the BCD conversion process. The octal number is first divided into digits according to place value. Each octal digit is then converted into an equivalent binary number using only three digits.Converting a decimal number to an octal number is a process of repetitive division by the number 8.After the quotient determined，the remainder is brought down as the place value.When the quotient is even with no remainder，a 0 is transferred to the place position.The number for converting 409810 to base 8 is 100028.Converting a binary number to an octal number is an importantconversion process of digital circuits. Binary numbers are first processed at a very output circuit then accepts this signal and converts it to an octal signal displayed on a readout device.must first be divided into groups of three，starting at the octal point.Each binary group is then converted into an equivalent octal number.These numbers are then combined，while remaining in their same respective places，to represent the equivalent octal number.3.2.4 Hexadecimal Number SystemThe digital systems to process large number values.The base of this system is 16，which means that the largest number used in a place is 15.Digits used by this system are the numbers 0-9 and the letters A-F. The letters A-P are used to denote the digits 10-15，respectively. The place values to the left of the .The process of changing a proper digital order.The place values，or powers of the base，are then positioned under the respective digits in step 2.In step 3，the value of each digit is recorded. The values in steps 2 and 3 are then multiplied together and added. The sum gives the decimal equivalent value of a . Initially，the converted to a binary number using four digits per group. The binary group is combined to form the equivalent binary number.The conversion of a decimal number to a ，as with other number systems. In this procedure the division is by 16 and remainders can be as large as 15.Converting a binary number to a groups of four digits，starting at the converted to a digital circuit-design applications binary signals arefar superior to those of the octal，decimal，or be processed very easily through electronic circuitry，since they can be represented by two stable states of operation. These states can be easily defined as on or off, 1 or 0，up or down，voltage or no voltage，right or left，or any other two-condition states. There must be no in-between state.The symbols used to define the operational state of a binary system are very important.In positive binary logic，the state of voltage，on，true，or a letter designation (such as A ) is used to denote the operational state 1 .No voltage，off，false，and the letter A are commonly used to denote the 0 condition. A circuit can be set to either state and will remain in that state until it is caused to change conditions.Any electronic device that can be set in one of two operational states or conditions by an outside signal is said to be bistable. Relays，lamps，switches，transistors, diodes and ICs may be used for this purpose. A bistable device .By using many of these devices，it is possible to build an electronic circuit that will make decisions based upon the applied input signals. The output of this circuit is a decision based upon the operational conditions of the input. Since the application of bistable devices in digital circuits makes logical decisions，they are commonly called binary logic circuits.If we were to draw a circuit diagram for such a system，including all the resistors，diodes，transistors and interconnections，we would face an overwhelming task, and an unnecessary one.Anyone who read the circuit diagram would in their mind group the components into standard circuits and think in terms of the" system" functions of the individual gates. Forthis reason，we design and draw digital circuit with standard logic symbols. Three basic circuits of this type are used to make simple logic decisions.These are the AND circuit, OR circuit, and the NOT circuit.Electronic circuits designed to perform logic functions are called gates.This term refers to the capability of a circuit to pass or block specific digital signals.The logic-gate symbols are shown in Fig.3-1.The small circle at the output of NOT gate indicates the inversion of the signal. Mathematically，this action is described as A=.Thus without the small circle，the rectangle would represent an amplifier (or buffer) with a gain of unity.An AND gate the 1 state simultaneously，then there will be a 1 at the output.The AND gate in Fig. 3-1 produces only a 1 out-put when A and B are both 1. Mathematically，this action is described as A·B=C. This expression shows the multiplication operation. An OR gate Fig.3-1 produces a when either or both inputs are l.Mathematically，this action is described as A+B=C. This expression shows OR addition. This gate is used to make logic decisions of whether or not a 1 appears at either input.An IF-THEN type of sentence is often used to describe the basic operation of a logic state.For example，if the inputs applied to an AND gate are all 1，then the output will be 1 .If a 1 is applied to any input of an OR gate，then the output will be 1 .If an input is applied to a NOT gate，then the output will be the opposite or inverse.The logic gate symbols in Fig. 3-1 show only the input and output connections. The actual gates，when wired into a digital circuit, would pin 14 and 7.3.4 Combination Logic GatesWhen a NOT gate is combined with an AND gate or an OR gate，it iscalled a combination logic gate. A NOT-AND gate is called a NAND gate，which is an inverted AND gate. Mathematically the operation of a NAND gate is A·B=. A combination NOT-OR ，or NOR，gate produces a negation of the OR function.Mathematically the operation of a NOR gate is A+B=.A 1 appears at the output only when A is 0 and B is 0.The logic symbols are shown in Fig. 3-3.The bar over C denotes the inversion，or negative function，of the gate.The logic gates discussed .In actual digital electronic applications，solid-state components are ordinarily used to accomplish gate functions.Boolean algebra is a special form of algebra that was designed to show the relationships of logic operations.Thin form of algebra is ideally suited for analysis and design of binary logic systems.Through the use of Boolean algebra，it is possible to write mathematical expressions that describe specific logic functions.Boolean expressions are more meaningful than complex word statements or or elaborate truth tables.The laws that apply to Boolean algebra are used to simplify complex expressions. Through this type of operation it may be possible to reduce the number of logic gates needed to achieve a specific function before the circuits are designed.In Boolean algebra the variables of an equation are assigned by letters of the alphabet.Each variable then exists in states of 1 or 0 according to its condition.The 1，or true state，is normally represented by a single letter such as A，B or C.The opposite state or condition is then described as 0，or false，and is represented by or A’.This is described as NOT A，A negated，or A complemented.Boolean algebra is somewhat different from conventional algebra withrespect to mathematical operations.The Boolean operations are expressed as follows:Multiplication:A AND B，AB，,A·BOR addition:A OR B .A+BNegation，or complementing:NOT A，，A’Assume that a digital logic circuit only C is on by itself or when A，B and C are all on expression describes the desired output. Eight (23) different combinations of A，B，and C exist in this expression because there are three，inputs. Only two of those combinations should cause a signal that will actuate the output. When a variable is not on (0)，it is expressed as a negated letter. The original statement is expressed as follows: With A，B，and C on or with A off, B off, and C on ，an output (X）will occur:ABC+C=XA truth table illustrates if this expression is achieved or not.Table 3-1 shows a truth table for this equation. First，ABC is determined by multiplying the three inputs together.A 1 appears only when the A，B，and C inputs are all 1.Next the negated inputs A andB are determined.Then the products of inputs C，A，and B are listed.The next column shows the addition of ABC and C.The output of this equation shows that output 1 is produced only when C is 1 or when ABC is 1.A logic circuit to accomplish this Boolean expression is shown in Fig. 3-4.Initially the equation is analyzed to determine its primary operational function.Step1 shows the original equation.The primary function is addition，since it influences all parts of the equation in some way.Step 2 shows the primary function changed to a logic gate diagram.Step 3 showsthe branch parts of the equation expressed by logic diagram，with AND gates used to combine terms.Step 4 completes the process by connecting all inputs together.The circles at inputs，of the lower AND gate are used to achieve the negative function of these branch parts.The general rules for changing a Boolean equation into a logic circuit diagram are very similar to those outlined.Initially the original equation must be analyzed for its primary mathematical function.This is then changed into a gate diagram that is inputted by branch parts of the equation.Each branch operation is then analyzed and expressed in gate form.The process continues until all branches are completely expressed in diagram formmon inputs are then connected together.3.5 Timing and Storage ElementsDigital electronics involves a number of items that are not classified as gates.Circuits or devices of this type the operation of a system.Included in this system are such things as timing devices，storage elements，counters，decoders，memory，and registers.Truth tables symbols，operational characteristics，and applications of these items will be presented an IC chip. The internal construction of the chip cannot be effectively altered. Operation is controlled by the application of an external signal to the input. As a rule，very little work can be done to control operation other than altering the input signal.The logic circuits in Fig. 3-4 are combinational circuit because the output responds immediately to the inputs and there is no memory. When memory is a part of a logic circuit，the system is called sequential circuit because its output depends on the input plus its an input signal isapplied.A bistable multivibrator，in the strict sense，is a flip-flop. When it is turned on，it assumes a particular operational state. It does not change states until the input is altered.A flip-flop opposite polarity.Two inputs are usually needed to alter the state of a flip-flop. A variety of names are used for the inputs.These vary a great deal between different flip-flops.1. R-S flip-flopsFig.3-5 shows logic circuit construction of an R-S flip-flop. It is constructed from two NAND gates. The output of each NAND provides one of the inputs for the other NAND. R stands for the reset input and S represents the set input.The truth table and logic symbol are shown in Fig. 3-6.Notice that the truth table is somewhat more complex than that of a gate. It shows, for example，the applied input, previous output，and resulting output.To understand the operation of an R-S flip-flop，we must first look at the previous outputs.This is the status of the output before a change is applied to the input. The first four items of the previous outputs are Q=1 and =0. The second four states this case of the input to NANDS is 0 and that is 0，which implies that both inputs to NANDR are 1.By symmetry，the logic circuit will also stable with Q0 and 1.If now R momentarily becomes 0，the output of NANDR，，will rise to resulting in NANDS be realized by a 0 at S.The outputs Q and are unpredictable when the inputs R and S are 0 states.This case is not allowed.Seldom would individual gates be used to construct a flip-flop，rather than one of the special types for the flip-flop packages on a single chipwould be used by a designer.A variety of different flip-flops are used in digital electronic systems today. In general，each flip-flop type R-S-T flip-flop for example .is a triggered R-S flip-flop. It will not change states when the R and S inputs assume a value until a trigger pulse is applied. This would permit a large number of flip-flops to change states all at the same time. Fig. 3-7 shows the logic circuit construction. The truth table and logic symbol are shown in Fig. 3-8. The R and S input are thus active when the signal at the gate input (T) is 1 .Normally，such timing，or synchronizing，signals are distributed throughout a digital system by clock pulses，as shown in Fig. 3-9.The symmetrical clock signal provides two times each period.The circuit can be designed to trigger at the leading or trailing edge of the clock. The logic symbols for edge trigger flip-flops are shown in Fig.3-10.2. J-K flip-flopsAnother very important flip-flop unpredictable output state. The J and K inputs addition to this，J-K flip-flops may employ preset and preclear functions. This is used to establish sequential timing operations. Fig.3-11 shows the logic symbol and truth table of a J-K flip-flop.3. 5. 2 CountersA flip-flop be used in switching operations，and it can count pulses.A series of interconnected flip-flops is generally called a register.Each register can store one binary digit or bit of data. Several flip-flops connected form a counter. Counting is a fundamental digital electronic function.For an electronic circuit to count，a number of things must beachieved. Basically，the circuit must be supplied with some form of data or information that is suitable for processing. Typically，electrical pulses that turn on and off are applied to the input of a counter. These pulses must initiate a state change in the circuit when they are received. The circuit must also be able to recognize where it is in counting sequence at any particular time. This requires some form of memory. The counter must also be able to respond to the next number in the sequence. In digital electronic systems flip-flops are primarily used to achieve counting. This type of device is capable of changing states when a pulse is applied，output pulse.There are several types of counters used in digital circuitry today.Probably the most common of these is the binary counter.This particular counter is designed to process two-state or binary information. J-K flip-flops are commonly used in binary counters.Refer now to the single J-K flip-flop of Fig. 3-11 .In its toggle state，this flip-flop is capable of achieving counting. First，assume that the flip-flop is in its reset state. This would cause Q to be 0 and Q to be 1 .Normally，we are concerned only with Q output in counting operations. The flip-flop is now connected for operation in the toggle mode. J and K must both be made the 1 state. When a pulse is applied to the T，or clock，input，Q changes to 1.This means that with one pulse applied，a 1 is generated in the output. The flip-flop the next pulse arrives，Q resets，or changes to 0. Essentially，this means that two input pulses produce only one output pulse. This is a divide-by-two function.For binary numbers，counting is achieved by a number of divide-by-two flip-flops.To count more than one pulse，additional flip-flops must be employed. For each flip-flop added to the counter，its capacity is increased by the power of 2. With one flip-flop the maximum count was 20，or 1 .For two flip-flops it would count two places，such as 20 and 21.This would reach a count of 3 or a binary number of 11.The count would be 00，01，10，and 11. The counter would then clear and return to 00. In effect, this counts four state changes. Three flip-flops would count three places，or 20，21，and 22.This would permit a total count of eight state changes.The binary values are 000，001，010，011，100，101，110 and 111.The maximum count is seven，or 111 .Four flip-flops would count four places，or 20，21，22，and 23.The total count would make 16 state changes. The maximum count would be 15，or the binary number 1111.Each additional flip-flop would cause this to increase one binary place.河南理工大学电气工程及其自动化专业中英双语对照翻译。
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沧州师范学院专业外语阅读文献综述学院机械与电气工程学院姓名赵汝志学号**********专业电气工程及其自动化班级2014级1班2017 年 1 月电动机的简单介绍摘要：电动机是指依据电磁感应定律实现电能转换或传递的一种电磁装置。
它将电能转变为机械能，它主要包括一个用以产生磁场的电磁铁绕组或分布的定子绕组和一个旋转电枢或转子。
在定子绕组旋转磁场的作用下，其在电枢鼠笼式铝框中有电流通过并受磁场的作用而使其转动。
这些机器中有些类型可作电动机用，也可作发电机用。
它是将电能转变为机械能的一种机器。
通常电动机的作功部分作旋转运动，这种电动机称为转子电动机；也有作直线运动的，称为直线电动机。
关键词：电动机；电磁装置一、基本介绍1、发明过程：电动机使用了通电导体在磁场中受力的作用的原理，发现这一原理的是丹麦物理学家—奥斯特，由于受康德哲学与谢林的自然哲学的影响，坚信自然力是可以相互转化的，长期探索电与磁之间的联系。
1820年4月终于发现了电流对磁针的作用，即电流的磁效应。
同年7月21日以《关于磁针上电冲突作用的实验》为题发表了他的发现。
这篇短短的论文使欧洲物理学界产生了极大震动，导致了大批实验成果的出现，由此开辟了物理学的新领域──电磁学。
2、国内现状：我国的电动机生产开始于1917年，该行业在国内已经形成比较完整的产业体系。
我国电动机制造行业随着电力发展呈现出勃勃生机，产销规模和经济效益都有了大幅度提高。
我国电机产品虽然种类繁多，但效率普遍不高。
二、基本分类电动机按工作电源种类划分：可分为直流电机和交流电机。
直流电动机按结构及工作原理可划分：无刷直流电动机和有刷直流电动机。
有刷直流电动机可划分：永磁直流电动机和电磁直流电动机。
电磁直流电动机划分：串励直流电动机、并励直流电动机、他励直流电动机和复励直流电动机。
永磁直流电动机划分：稀土永磁直流电动机、铁氧体永磁直流电动机和铝镍钴永磁直流电动机。
其中交流电机还可分：同步电机和异步电机。
同步电机可划分：永磁同步电动机、磁阻同步电动机和磁滞同步电动机。
异步电机可划分：感应电动机和交流换向器电动机。
感应电动机可划分：三相异步电动机、单相异步电动机和罩极异步电动机等。
交流换向器电动机可划分：单相串励电动机、交直流两用电动机和推斥电动机。
三、工作原理电动机种类有很多种，下面简单介绍三相异步电动机的工作原理：当电动机的三相定子绕组通入三相对称交流电后，将产生一个旋转磁场，该旋转磁场切割转子绕组，从而在转子绕组中产生感应电流，载流的转子导体在定子旋转磁场作用下将产生电磁力，从而在电机转轴上形成电磁转矩，驱动电动机旋转，并且电机旋转方向与旋转磁场方向相同。
当三相异步电机接入三相交流电源时，三相定子绕组流过三相对称电流产生的三相磁动势并产生旋转磁场，该磁场以同步转速n0沿定子和转子内圆空间作顺时针方向旋转。
四、基本结构三相异步电动机的两个基本组成部分为定子和转子。
此外还有端盖、风扇等附属部分。
1、定子铁心：定子铁心是异步电动机主磁通磁路的一部分。
为了使异步电动机能产生较大的电磁转矩，希望有一个较强的旋转磁场，同时由于旋转磁场对定子铁心以同步转速旋转，定子铁心中的磁通的大小与方向都是变化的，必须设法减少由旋转磁场在定子铁心中所引起的涡流损耗和磁滞损耗，因此，定子铁心由导磁性能较好的0.5mm厚且冲有一定槽形的硅钢片叠压而成。
2、定子绕组：定子绕组是异步电机定子部分的电路，它也是由许多线圈按一定规律联接面成。
能分散嵌入半闭口槽的线圈由高强度漆包圆铜线或圆铝线绕成，放入半开口槽的成型线圈用高强度漆包扁沿线或扁铜线，或用玻璃丝包扁铜线绕成。
开口槽也放入成型线圈，其绝缘通常采用云母带，线圈放入槽内必须与槽壁之间隔有“槽绝缘”，以免电机在运行时绕组对铁心出现击穿或短路故障。
3、转子铁心：转子铁心也是电动机主磁通磁路的一部分，一般也由0.5毫米厚冲槽的硅钢片叠成，铁心固定在转轴或转子支架上。
整个转子铁心的外表面成圆柱形。
4、转子绕组：转子绕组分为笼型和绕线型两种结构，下面介绍绕线型绕组。
它是一个对称三相绕组，这个对称三相绕组接成星形，并接到转轴上三个集电环，再通过电刷使转子绕组与外电路接通。
五、结论电动机的运用在国内越来越多，种类繁多但是效率不高。
在了解了电动机的基本原理后，随着对电动机认识的加深，未来会有更多高效率的电机产生。
本文简单的提供了电动机的基础知识，是为了方便读者更好的了解电动机。
参考文献[1]孙建忠，刘凤春。
电机与拖动[M]。
机械工业出版社。
[2]邱关源。
电路[M]。
高等教育出版社。
A brief introduction to the motorAbstract:Electromagnetism is a kind of electromagnetism which can realize the conversion or transmission of electric energy according to the law of electromagnetic induction. It converts electrical energy into mechanical energy and consists essentially of an electromagnet winding or distributed stator windings for generating a magnetic field and a rotating armature or rotor. In the stator windings under the action of rotating magnetic field, the armature squirrel-cage aluminum in the current through the magnetic field and the role of its rotation. Some of these machines can be used for electric motors as well as generators. It is a machine that converts electrical energy into mechanical energy. Usually the work part of the motor for rotary motion, this motor is called the rotor motor; also for linear motion, known as the linear motor.Keywords: motor; electromagnetic deviceFirst, the basic introduction1, the invention process:The principle of the motor using the force of the conducting conductor in the magnetic field was discovered by the Danish physicist Oersted, because of the influence of Kant's philosophy and Schelling's natural philosophy, that the forces of nature can be transformed into each other , Long-term exploration of the relationship between electricity and magnetic. In 1820 April finally found the role of current on the magnetic needle, that is, the magnetic effect of the current. In July 21st the same year on the "needle on the power of the role of the experiment" as the title of his discovery. This short paper to the European physics community had a great shock, resulting in a large number of experimental results, which opened up a new field of physics ──electromagnetics.2, the domestic situation:China's motor production began in 1917, the industry in China has formed a relatively complete industrial system. China's electric motor manufacturing industry with the development of electric power has shown vitality, production and marketing scale and economic benefits have been greatly improved. Although a wide range of motor products in China, but the efficiency is generally not high.Second, the basic classificationThe motor according to the type of power supply division: can be divided into DC motor and AC motor. DC motor by structure and working principle can be divided into: brushless DC motor and brush DC motor. Brush DC motor can be divided into: permanent magnet DC motor and electromagnetic DC motor. Electromagnetic DC motor division: series excitation DC motor, shunt DC motor, he excited DC motor and DC motor excitation. Permanent magnet DC motor division:rare earth permanent magnet DC motor, ferrite permanent magnet DC motor and aluminum nickel cobalt permanent magnet DC motor. Which AC motor can be divided into: synchronous motor and asynchronous motor. Synchronous motor can be divided: permanent magnet synchronous motor, reluctance synchronous motor and hysteresis synchronous motor. Induction motor can be divided into: induction motor and AC commutator motor. Induction motor can be divided into: three-phase asynchronous motor, single-phase asynchronous motor and shaded pole asynchronous motor. AC commutator motor can be divided into: single-phase series motor, AC-DC dual-motor and repulsion motor.Third, the working principleThere are many types of motor, the following simple three-phase induction motor works: When the three-phase stator winding of the motor into the three-phase AC, will produce a rotating magnetic field, the rotating magnetic field rotor winding, which in the rotor winding The rotor current of the rotor will produce electromagnetic force under the action of the rotating magnetic field of the stator, so that the electromagnetic torque will be formed on the motor shaft, the motor will rotate and the direction of rotation will be the same as the rotating magnetic field. When the three-phase asynchronous motor access to three-phase AC power, three-phase stator windings flow through the three-phase symmetrical current generated by three-phase MMF and produce a rotating magnetic field, the synchronous speed of the magnetic field along the stator and rotor inner space for n0 Clockwise rotation.Fourth, the basic structureThe two basic components of a three-phase asynchronous motor are the stator and the rotor. In addition, end caps, fans and other ancillary parts.1, the stator core:The stator core is a part of the main magnetic flux path of the induction motor. In order to make the induction motor can produce a larger electromagnetic torque, it is desirable to have a strong rotating magnetic field, and the magnetic flux in the stator core is changed in size and direction due to the rotating magnetic field rotating at a synchronous speed to the stator core. So that the stator core is made of a 0.5 mm-thick silicon steel sheet having a good magnetic permeability and laminated with a certain groove-shaped silicon steel sheet, so as to reduce the eddy current loss and hysteresis loss caused by the rotating magnetic field in the stator core.2, the stator windings:Stator winding is the stator part of the asynchronous motor circuit, it is also by a number of coils connected by a certain law into the surface. Can be dispersed semi-closed slot embedded in the coil by the high-strength enamelled round copper wire or round aluminum wire into thehalf-slot slot into the forming coil with high-strength enamel along the flat or flat copper wire, or glass wire wrapped copper wire to make. Open slot is also placed in the forming coil, the insulation is usually used mica tape, the coil into the slot wall must be separated with the slot insulation to prevent the motor running in the winding of the core breakdown or short circuit failure.3, the rotor core:The rotor core is also part of the main magnetic flux path of the motor, and is usually also made of silicon steel sheet of 0.5 mm thick punching groove, and the iron core is fixed on the shaft or the rotor bracket. The outer surface of the entire rotor core is cylindrical.4, the rotor winding:Rotor winding is divided into two types of cage and winding structure, the following describes the winding winding. It is a symmetrical three-phase winding, the symmetrical three-phase windings connected to the star-shaped, and connected to the shaft on the three collector ring, and then through the brush to the rotor winding connected with the external circuit. V. ConclusionThe use of motors in the country more and more, but the efficiency is not high. In the understanding of the basic principles of the motor, with the deepening of the understanding of the motor, the future will have more efficient motor production. This article simply provides the basic knowledge of the motor is to facilitate the reader a better understanding of the motor.references[1] Sun Jianzhong, Liu Fengchun. Motor and drag [M]. Machinery Industry Press.[2] Qiu Guan source. Circuit [M]. Higher Education Press.。