电气自动化专业英语课件.ppt

1、高等职业教育自动化专业 “双证课程”培养方案规划教材自动化专业英语自动化专业英语English for AutomationEnglish for AutomationContentsEnglish for AutomationReading AUnit 1The main components used in electronics are of two general types: passive (e.g. resistors and capacitors) and active (e.g. transistors and integrated circuits). The main d

2、ifference between active and passive components is that active ones require to be powered in some way to make them work. Passive ComponentsThe ResistorA resistor (Figure 1-1) is a piece of material that obeys Ohms Law. The name comes from its main property; it resists the flow of charge through itse

3、lf, hence allowing us to control the current. Resistors can be made of various kinds of material, but whatever the choice it must conduct some electricity otherwise it wouldnt be of any use. English for AutomationTwo wires are connected to opposite ends of the resistor (Figure 1-2). When we apply a

4、potential difference between the wires we set up a current from one wire to the other, through the resistor. The size of the current is proportional to the difference in voltage between the wires. The resistance (in units of Ohms) is defined as the ratio of the applied voltage, V (in Volts), divided

5、 by the current, I (in Amps), produced by the applied voltage.Unit 1The value is usually displayed using standard colour code (Figure 1-3). English for AutomationUnit 1The CapacitorIf you look at a catalogue of electronic components youll find an enormous variety of sizes and types of capacitor. How

6、ever, for most purposes we can divide capacitors into two basic types: dielectric and electrolytic.A capacitor acts as a charge store (Figure 1-4). It contains a pair of metal plates separated by a thin sheet of insulating material. The plates are electrically neutral - the number of positive proton

7、s in each exactly equals the number of negative electrons. However, if we connect wires to the plates and apply external voltage we can drag electrons off one plate and push them on to the other.English for AutomationUnit 1This takes energy, i.e. we have to do work charging the capacitor. The result

8、 is a capacitor with one plate positively charged and the other negatively charged. The energy used to move charge is stored by this imbalance. If we connect two plates together with a resistor, the electrons rush back home releasing their energy again. The voltage between the plates of a charged ca

9、pacitor is proportional to the amount of charge moved. The charge/voltage ratio for any specific capacitor is called the capacitance (Figure 1-5).The DiodeThere are a number of different electronic devices which tend to be called diodes (Figure 1-6). Although theyre made differently they all have th

10、ree things in common. English for AutomationUnit 1 They have two leads like a resistor. The current they pass depends upon the voltage between the leads. They do not obey Ohms law! As an example we will use a typical diode called a pn-junction. This allows us to explain behavior of diodes. Remember,

11、 however, that there are other sorts of diodes which are built differently but show the same general behavior. We create a pn-junction by joining together two pieces of semiconductor, one doped n-type, the other p-type. This causes a depletion zone to form around the junction (the join) between the

12、two materials. This zone controls the behavior of the diode.English for AutomationUnit 1Notes1. When we apply a potential difference between the wires we set up a current from one wire to the other, through the resistor. 本句是由When we引导的时间状语从句。本句可译为：当在两导线间施加一个电势差时，就会有电流通过电阻器从一根导线传递到另一根导线。2. If we conn

13、ect wires to the plates and apply an external voltage we can drag electrons off one plate and push them on to the other. 本句是由If we引导的条件状语从句，we can drag为主句部分。本句可译为：如果我们将导线连接到金属板上，并且外加电压，电子就从一块金属板扯拽到另一块上。3. There are other sorts of diodes which are built differently but show the same general behavior.

14、 本句为简单句。本句可译为：还有很多种不同结构的二极管，但他们有相同的一般性能。 English for AutomationUnit 1ExerciseEXERCISE 1Mark the following statements with T (True) or F (False) according to the passage.1. Active components are different from passive components in some way to make them work. 2. The resistance is often considered as

15、the ratio of the current, I (in Amps).3. If wires are connected to the plates and an external voltage is applied electrons can be dragged off one plate and they are pushed on to the other.4. Although diodes are made differently they all have the same in three ways.5. Some of diodes are differently a

16、nd show different behavior.TFTTFEnglish for AutomationUnit 1ExerciseEXERCISE 2Translate the following phrases into Chinese or English.1. active components _2. 欧姆定律3. potential difference _4. 施加电压5. insulating material _6. 正质子7. electronic device _8. 耗尽层有源元件有源元件电势差电势差绝缘材料绝缘材料电子器件电子器件Ohms Lawapplied v

17、oltagepositive protonsdepletion zoneEnglish for AutomationUnit 1Reading BActive ComponentsJunction Field Effect TransistorsJunction field effect transistors (JFETs) come in two flavors, p-channel and n-channel (Figure 1-7). In each case a bar, or channel, of one type of semiconductor material is loc

18、ated inside a bulk material of the other kind i.e. p inside n, or n inside p. A pair of metallic contacts is placed at each end of the channel. When we apply a voltage between these, a current can flow along the channel from one contact to the other. The contact which launches charges along the chan

19、nel is called the source; the one that eats them at the other end is called the drain. English for AutomationUnit 1In an n-channel device, the channel is made of n-type semiconductor, so the charges free to move along the channel are negatively (hence n) charged - they are electrons. In a p-channel

20、device the free charges which move from end-to-end are positively (hence p) charged - they are holes (Figure 1-8). Remember that a hole is the absence of an electron. In each case the source puts fresh charges into the channel while the drain removes them at the other end.English for AutomationUnit

21、1Some of the basic properties exhibited by a Bipolar Transistor are immediately recognizable as being diode-like. However, when the filling of the sandwich is fairly thin some interesting effects become possible that allow us to use the Transistor as an amplifier or a switch. To see how the Bipolar

22、Transistor works we can concentrate on the NPN variety.Bipolar TransistorA Bipolar Transistor (Figure 1-9) essentially consists of a pair of PN Junction Diodes that are joined back-to-back. This forms a sort of a sandwich where one kind of semiconductor is placed in-between two others. There are the

23、refore two kinds of bipolar sandwich, the NPN and PNP varieties. The three layers of the sandwich are conventionally called the Collector, Base, and Emitter. The reasons for these names will become clear later once we see how the transistor works.English for AutomationUnit 1Figure 1-10 shows the ene

24、rgy levels in an NPN transistor when we arent externally applying any voltages. We can see that the arrangement looks like a back-to-back pair of PN Diode junctions with a thin P-type filling between two N-type slices of bread. In each of the N-type layers conduction can take place by the free movem

25、ent of electrons in the conduction band. In the P-type (filling) layer conduction can take place by the movement of the free holes in the valence band. However, in the absence of any externally applied electric field, we find that depletion zones form at both PN-Junctions, so no charge wants to move

26、 from one layer to another.English for AutomationUnit 1C o n s i d e r n o w w h a t happens when we apply a moderate voltage between the Collector and Base parts of the transistor. The polarity of the applied voltage is chosen to increase the force pulling the N-type electrons and P-type holes apar

27、t (Figure 1-11). This widens the depletion zone between the Collector and base and so no current will flow. In effect we have reverse-biased the Base-Collector diode junction. The precise value of the Base-Collector voltage we choose doesnt really matter to what happens provided we dont make it too

28、big and blow up the transistor! English for AutomationExerciseUnit 1EXERCISE 3Choose the best electronic components according to the information given._A. Transistor B. Diode C. Capacitor D. Resistor E. Connector F. LEDCEBFDAEnglish for AutomationExerciseUnit 1EXERCISE 4Abbreviations are very useful

29、 in practical work. Read them and then translate them into corresponding Chinese terms.1. A.C. Alternating Current _2. ADC Analog/Digital Conversion _3. AF Audio Frequency _4. AFC Automatic Frequency Control _ 5. AGC Automatic Gain Control _ 6. AM Amplitude Modulated _ 交流交流数数/模转换模转换音频音频自动频率控制自动频率控制自

30、动增益控制自动增益控制调幅调幅English for AutomationUnit 1Glance at the structure The following is the Electronic Component Structure.SampleEnglish for AutomationUnit 1Explanations of the NPN Transistor TermsNo.NameExplanation1Emitter (E)射极2diffusion扩散3Base (B)基极4drift漂移5Collector (C)集电极6n-type n型7depletion region

31、 耗尽层8p-typeP型9NPNNPN型晶体管English for AutomationUnit 1EXERCISE 5The following is the Electronic Component Structures. After reading them, you are required to choose the suitable words or phrases given below. Emitter-Base Junction (EBJ) Emitter (E) PNP p-type Collector-Base Junction (CBJ) n- type Base

32、regionp-type Emitter region Collector (C) Base (B)English for AutomationUnit 11._ 2. _3. _ 4. _5. _ 6. _7. _ 8. _9. _Emitter (E)p-type Emitter regionn- type Base region p-type Collector regionCollector (C)Emitter-Base Junction (EBJ) Base (B)Collector-Base Junction (CBJ)PNPEnglish for AutomationUnit

33、1Section AThe following is the Typical Vertical Chip Aluminum Electrolytic Capacitor Construction, and you can understand the name of the Capacitor.Sample English for AutomationUnit 1Explanations of the Capacitor ConstructionNo.NameExplanation1Aluminum case铝壳2Plate底座3Electrode lead电极引线4In-mold suppl

34、emental terminal型内附加端子5Seal Rubber密封橡胶6Adhesive resin for bonding粘合树脂胶7Element元件English for AutomationUnit 1EXERCISE 6Complete the information by translating the part given in Chinese.Structure of Aluminum Electrolytic Capacitor (Radial Lead Type)English for AutomationUnit 11. A. lead wire B. insula

35、tor C. plate2. A. element B. sealant C. electrode3. A. seal rubber B. lead wire C. metal case4. A. capacitor element B. sealant C. aluminum case5. A. resistor B. coil C. conductr6. A. integrated circuit B. negative electron C. fastening tape7. A. anode layer B. conduction band C. bulk material8. A.

36、applied voltage B. electrolytic paper C. electric field9. A. cathode layer B. potential difference C. valence bandABCABCABAEnglish for AutomationUnit 1Section BThis section will help you how to understand Aluminum Electrolytic Capacitor failure.Sample Typical Aluminum Electrolytic Capacitor Failure

37、Modes and Their CausesEnglish for AutomationUnit 1English for AutomationUnit 1EXERCISE 7The following is the manufacture of Aluminum Electrolytic Capacitor. After reading them, you are required to choose the interpretations given in Column C match the Functions given in Column A.ABCThe anode in the

38、aluminum electrolytic capacitor is made from a high-purity aluminum foil with an aluminum oxide thin film dielectric on its surface. The manufacturing process flow for the aluminum electrolytic capacitors is as follows:1. A. Step 1: SlitThe anode foil, cathode foil, and electrolyte paper are cut to

39、the specified width from the source rolls of the specified length.BEnglish for AutomationUnit 12. B. Step 2 Lead AttachmentLeads for contacting the cathode and anode foil electrodes are attached either by crimping or by ultrasonic welding.3. C. Step 3 CoilingThe electrolytic paper is layered between

40、 the anode foil and the electrode foil. A coiled construction separates the electrodes. When the structure is coiled in this manner it is known as an “element”.4. D. Step 4 AssemblyThe rubber plug is attached to the filled element. Then, the element is placed in the case.5. E. Step 5 Sleeve Attachme

41、ntThe case is slipped into a sleeve printed with the rated voltage, capacitance, and polarity. After which, the sleeve is heat shrunk on to the case.DAECEnglish for AutomationUnit 1Practical ActivityHow Coin and Multilayer Electric Double-layer Capacitors Are ManufacturedActivated charcoal and binde

42、rs are mixed and formed into a sheet.Disks with specific diameters are punched out of the electrode sheet.A conductive adhesive is used to adhere the electrodes punched from the sheet to the metal case and cap that will form the capacitor.After drying, the case and cap (with the electrodes glued ins

43、ide) are filled with an organic liquid electrolyte inside a dry box.The case and cap are assembled together with a separator and a gasket, and the case is crimped in a case to seal the opening, forming a coin cell.English for AutomationUnit 1100% of the coin cells are subjected to electrical testing

44、.Because the withstand voltage of the individual coin cells is between 2.8 and 3.0 V, two or three of these cells are connected in series.English for AutomationUnit 1Part V Listening and SpeakingTalking About ProductsDialogue OneA: Whats this, Mike?B: Its an aluminum capacitor.A: Is it made of alumi

45、num?B: Yes. They are composed of two rolled up strips of aluminum foils.A: Whats its capacitance range?B: It covers the capacitance ranging from 0.1F to 500,000F.A: Woo, it really has a wide range. B: And it also has a wide tolerance range, usually 20% or more.A: How about its working voltage?B: Wor

46、king voltages range from 10V to 100V.A: Oh, so they must have wide applications. B: Actually, they are not suited for high-frequency coupling applications.English for AutomationUnit 1Dialogue TwoA: What are you doing, Sam?B: Im soldering a surface-mounted aluminum capacitor.A: Familiarize yourself w

47、ith the instructions, please. Otherwise, it would be dangerous!B: Really? I have no idea about it. A: It may cause an explosion, fire, or other serious troubles!B: Oh my God! Thats awful!A: So youd better solder it under specified operating conditions!B: Could you give me some hints?A: Firstly, you

48、should keep the operating temperature and ripple current in specified ranges.B: Whats the consequence if I would not do like that?A: It will be overheated, resulting perhaps in short-circuit, ignition, or other fatal fault!B: Is there anything else I should pay attention to?A: Yes. I have aluminum c

49、apacitor use instructions. Let me show you, come with me. B: Thank you very much. English for AutomationUnit 1New Words (1)electronic a. 电子的 component n. 元件electronics n. 电子设备passive a. 无源的active a. 有源的resistor n. 电阻器capacitor n. 电容器transistor n. 晶体管integrated a. 集成的circuit n. 电路ohm n. 欧姆property n.

50、 性能charge n. 电荷 v. 充电current n. 电流conduct v. 导电electricity n. 电potential n. 电势wire n. 导线voltage n. 电压resistance n. 电阻ratio n. 比率apply v. 施加amp n. 安培volt n. 伏特value n. 值dielectric a. 电介质的electrolytic a. 电解质的plate n. 金属板sheet n. 板insulate v. 绝缘neutral a. 中性的positive a. 正的proton n. 质子negative a. 负的elec