1. 电气技术专业英语 朱一纶 主编 中国电力出版社

2. Unit 9 Motor Controller 课件制作 : 吴岱曦

3. Index Text Text Text –1. Introduction 1. Introduction1. Introduction –2. Relay 2. Relay2. Relay –3. Contactor 3. Contactor3. Contactor

4. Reading materials Reading materials Reading materials Reading materials –1. Time Relay 1. Time Relay1. Time Relay –2. Novel controller 2. Novel controller2. Novel controller –3. Experiment material 3. Experiment material3. Experiment material

5. Exercises Exercises Exercises –1. Put the Phrases into English 1. Put the Phrases into English1. Put the Phrases into English –2. Put the Phrases into Chinese 2. Put the Phrases into Chinese2. Put the Phrases into Chinese –3. Sentence Translation 3. Sentence Translation3. Sentence Translation –4. Translation 4. Translation4. Translation

6. Text

7. 1. Introduction A motor controller is a device or group of devices that serves to govern in some predetermined manner the performance of an electric motor. A motor controller is a device or group of devices that serves to govern in some predetermined manner the performance of an electric motor.

8. A motor controller might include a manual or automatic means for starting and stopping the motor, selecting forward or reverse rotation, selecting and regulating the speed, regulating or limiting the torque, and protecting against overloads and faults. A motor controller might include a manual or automatic means for starting and stopping the motor, selecting forward or reverse rotation, selecting and regulating the speed, regulating or limiting the torque, and protecting against overloads and faults.

9. A motor controller is connected to a power source such as a battery pack or power supply, and control circuitry in the form of analog or digital input signals. A motor controller is connected to a power source such as a battery pack or power supply, and control circuitry in the form of analog or digital input signals.

10. An electric current through a conductor will produce a magnetic field at right angles to the direction of electron flow. If that conductor is wrapped into a coil shape, the magnetic field produced will be oriented along the length of the coil.(Fig 9.1) An electric current through a conductor will produce a magnetic field at right angles to the direction of electron flow. If that conductor is wrapped into a coil shape, the magnetic field produced will be oriented along the length of the coil.(Fig 9.1)

11. Fig 9.1 direction of the magnetic field

12. The greater the current, the greater the strength of the magnetic field, all other factors being equal. The greater the current, the greater the strength of the magnetic field, all other factors being equal.

13. If we place a magnetic object near such a coil for the purpose of making that object move when we energize the coil with electric current, we have what is called a solenoid. If we place a magnetic object near such a coil for the purpose of making that object move when we energize the coil with electric current, we have what is called a solenoid.

14. The movable magnetic object is called an armature, and most armatures can be moved with either direct current (DC) or alternating current (AC) energizing the coil. The polarity of the magnetic field is irrelevant for the purpose of attracting an iron armature. The movable magnetic object is called an armature, and most armatures can be moved with either direct current (DC) or alternating current (AC) energizing the coil. The polarity of the magnetic field is irrelevant for the purpose of attracting an iron armature.

15. Solenoids can be used to electrically open door latches, open or shut valves, move robotic limbs, and even actuate electric switch mechanisms. However, if a solenoid is used to actuate a set of switch contacts, we have a device so useful it deserves its own name: the relay. Solenoids can be used to electrically open door latches, open or shut valves, move robotic limbs, and even actuate electric switch mechanisms. However, if a solenoid is used to actuate a set of switch contacts, we have a device so useful it deserves its own name: the relay.

16. 2. Relay Relays are extremely useful when we have a need to control a large amount of current and/or voltage with a small electrical signal. Relays are extremely useful when we have a need to control a large amount of current and/or voltage with a small electrical signal.

17. The relay coil which produces the magnetic field may only consume fractions of a watt of power, while the contacts closed or opened by that magnetic field may be able to conduct hundreds of times that amount of power to a load. In effect, a relay acts as a binary (on or off) amplifier. The relay coil which produces the magnetic field may only consume fractions of a watt of power, while the contacts closed or opened by that magnetic field may be able to conduct hundreds of times that amount of power to a load. In effect, a relay acts as a binary (on or off) amplifier.

18. Fig 9.2 Load controlled by a relay

19. In Fig 9.2, the relay's coil is energized by the low-voltage (12 V DC ) source, while the single-pole, single-throw (SPST) contact interrupts the high-voltage (480 V AC ) circuit. In Fig 9.2, the relay's coil is energized by the low-voltage (12 V DC ) source, while the single-pole, single-throw (SPST) contact interrupts the high-voltage (480 V AC ) circuit.

20. It is quite likely that the current required to energize the relay coil will be hundreds of times less than the current rating of the contact. Typical relay coil currents are well below 1 amp, while typical contact ratings for industrial relays are at least 10 amps. It is quite likely that the current required to energize the relay coil will be hundreds of times less than the current rating of the contact. Typical relay coil currents are well below 1 amp, while typical contact ratings for industrial relays are at least 10 amps.

21. One relay coil/armature assembly may be used to actuate more than one set of contacts. Those contacts may be normally- open, normally-closed, or any combination of the two. One relay coil/armature assembly may be used to actuate more than one set of contacts. Those contacts may be normally- open, normally-closed, or any combination of the two.

22. As with switches, the "normal" state of a relay's contacts is that state when the coil is de-energized, just as you would find the relay sitting on a shelf, not connected to any circuit. As with switches, the "normal" state of a relay's contacts is that state when the coil is de-energized, just as you would find the relay sitting on a shelf, not connected to any circuit.

23. Compare with transistors, relays have following advantages: Compare with transistors, relays have following advantages: 1.Relays can switch AC and DC, transistors can only switch DC. 2.Relays can switch high voltages, transistors cannot. 3.Relays are a better choice for switching large currents (> 5A). 4.Relays can switch many contacts at once.

24. 3. Contactor When a relay is used to switch a large amount of electrical power through its contacts, it is designated by a special name: contactor. In other words, a contactor is a large relay, usually used to switch current to an electric motor or other high-power load. When a relay is used to switch a large amount of electrical power through its contacts, it is designated by a special name: contactor. In other words, a contactor is a large relay, usually used to switch current to an electric motor or other high-power load.

25. Contactors typically have multiple contacts, and those contacts are usually (but not always) normally-open （ Fig 9.3 ）, so that power to the load is shut off when the coil is de-energized. Perhaps the most common industrial use for contactors is the control of electric motors. Contactors typically have multiple contacts, and those contacts are usually (but not always) normally-open （ Fig 9.3 ）, so that power to the load is shut off when the coil is de-energized. Perhaps the most common industrial use for contactors is the control of electric motors.

26. Fig 9.3 AC contactor

27. The top three contacts switch the respective phases of the incoming 3-phase AC power, typically at least 380 Volts for motors 1 horsepower or greater. The lowest contact is an "auxiliary" contact which has a current rating much lower than that of the large motor power contacts, but is actuated by the same armature as the power contacts. The top three contacts switch the respective phases of the incoming 3-phase AC power, typically at least 380 Volts for motors 1 horsepower or greater. The lowest contact is an "auxiliary" contact which has a current rating much lower than that of the large motor power contacts, but is actuated by the same armature as the power contacts.

28. The auxiliary contact is often used in a relay logic circuit, or for some other part of the motor control scheme, typically switching 120 Volt AC power instead of the motor voltage. One contactor may have several auxiliary contacts, either normally-open or normally-closed, if required. The auxiliary contact is often used in a relay logic circuit, or for some other part of the motor control scheme, typically switching 120 Volt AC power instead of the motor voltage. One contactor may have several auxiliary contacts, either normally-open or normally-closed, if required.

29. Large electric motors can be protected from damage through the use of overload heaters and overload contacts of thermal overloads. If the series-connected heaters get too hot from excessive current, the normally-closed overload contact will open, de-energizing the contactor sending power to the motor. Large electric motors can be protected from damage through the use of overload heaters and overload contacts of thermal overloads. If the series-connected heaters get too hot from excessive current, the normally-closed overload contact will open, de-energizing the contactor sending power to the motor.

30. This is the End of the Text

31. Reading materials

32. 1. Time Relay Some relays are constructed with a kind of "shock absorber" mechanism attached to the armature which prevents immediate, full motion when the coil is either energized or de-energized. Some relays are constructed with a kind of "shock absorber" mechanism attached to the armature which prevents immediate, full motion when the coil is either energized or de-energized.

33. This addition gives the relay the property of time-delay actuation. Time-delay relays can be constructed to delay armature motion on coil energization, de-energization, or both. This addition gives the relay the property of time-delay actuation. Time-delay relays can be constructed to delay armature motion on coil energization, de-energization, or both.

34. Time-delay relay contacts must be specified not only as either normally-open or normally-closed, but whether the delay operates in the direction of closing or in the direction of opening. The following is a description of the four basic types of time- delay relay contacts. Time-delay relay contacts must be specified not only as either normally-open or normally-closed, but whether the delay operates in the direction of closing or in the direction of opening. The following is a description of the four basic types of time- delay relay contacts.

35. First we have the normally-open, timed- closed (NOTC) contact （ Fig 9.4 ）. This type of contact is normally open when the coil is unpowered (de-energized). The contact is closed by the application of power to the relay coil, but only after the coil has been continuously powered for the specified amount of time. First we have the normally-open, timed- closed (NOTC) contact （ Fig 9.4 ）. This type of contact is normally open when the coil is unpowered (de-energized). The contact is closed by the application of power to the relay coil, but only after the coil has been continuously powered for the specified amount of time.

36. In other words, the direction of the contact's motion (either to close or to open) is identical to a regular NO contact, but there is a delay in closing direction. Because the delay occurs in the direction of coil energization, this type of contact is alternatively known as a normally-open, on-delay. In other words, the direction of the contact's motion (either to close or to open) is identical to a regular NO contact, but there is a delay in closing direction. Because the delay occurs in the direction of coil energization, this type of contact is alternatively known as a normally-open, on-delay.

37. Fig 9.4 Timing diagram of NOTC's operation

38. Next we have the normally-open, timed- open (NOTO) contact (Fig 9.5). Like the NOTC contact, this type of contact is normally open when the coil is unpowered (de-energized), and closed by the application of power to the relay coil. Next we have the normally-open, timed- open (NOTO) contact (Fig 9.5). Like the NOTC contact, this type of contact is normally open when the coil is unpowered (de-energized), and closed by the application of power to the relay coil.

39. However, unlike the NOTC contact, the timing action occurs upon de-energization of the coil rather than upon energization. Because the delay occurs in the direction of coil de-energization, this type of contact is alternatively known as a normally-open, off-delay: However, unlike the NOTC contact, the timing action occurs upon de-energization of the coil rather than upon energization. Because the delay occurs in the direction of coil de-energization, this type of contact is alternatively known as a normally-open, off-delay:

40. Fig 9.5 Timing diagram of NOTO's operation

41. Normally-closed, timed-open. Abbreviated "NCTO", these relays close immediately upon coil de-energization and open only if the coil is continuously energized for the time duration period. Also called normally- closed, on-delay relays. Normally-closed, timed-open. Abbreviated "NCTO", these relays close immediately upon coil de-energization and open only if the coil is continuously energized for the time duration period. Also called normally- closed, on-delay relays.

42. Normally-closed, timed-closed. Abbreviated "NCTC", these relays open immediately upon coil energization and close after the coil has been de-energized for the time duration period. Also called normally-closed, off -delay relays. Normally-closed, timed-closed. Abbreviated "NCTC", these relays open immediately upon coil energization and close after the coil has been de-energized for the time duration period. Also called normally-closed, off -delay relays.

43. 2. Novel controller Recent developments in drive electronics have allowed efficient and convenient control of these motors, where this has not traditionally been the case. The newest advancements allow for torque generation down to zero speed. Recent developments in drive electronics have allowed efficient and convenient control of these motors, where this has not traditionally been the case. The newest advancements allow for torque generation down to zero speed.

44. This allows the polyphase AC induction motor to compete in areas where DC motors have long dominated, and present an advantage in robustness of design, cost, and reduced maintenance. Here are some examples: This allows the polyphase AC induction motor to compete in areas where DC motors have long dominated, and present an advantage in robustness of design, cost, and reduced maintenance. Here are some examples:

45. A motor soft starter connects the motor to the power supply through a voltage reduction device and increases the applied voltage gradually or in steps. A motor soft starter connects the motor to the power supply through a voltage reduction device and increases the applied voltage gradually or in steps.

46. Fig 9.6 QJ Series auto-reduced voltage starter

47. QJ Series auto-reduced voltage starter (Fig 9.6) is applicable to infrequent reduced-voltage start up and stop of AC 50Hz three-phase squirrel-cage induction motor with voltage of 380V and power of 10, 14, 28, 40, 55 and 75kW in general industry. QJ Series auto-reduced voltage starter (Fig 9.6) is applicable to infrequent reduced-voltage start up and stop of AC 50Hz three-phase squirrel-cage induction motor with voltage of 380V and power of 10, 14, 28, 40, 55 and 75kW in general industry.

48. When the tapped autotransformer starts, it reduces the power supply voltage, so that the starting current reduces. This product also provides with thermal relay and under-voltage tripping gear. When the tapped autotransformer starts, it reduces the power supply voltage, so that the starting current reduces. This product also provides with thermal relay and under-voltage tripping gear.

49. When the motor is overloaded or the voltage of the line is at a certain value below the rated voltage, the motor will be switched off from the power supply to protect the motor. When the motor is overloaded or the voltage of the line is at a certain value below the rated voltage, the motor will be switched off from the power supply to protect the motor.

50. Fig 9.7 DK-1B type controller

51. DK-1B type controller (Fig 9.7) in TKZ series speed-adjustment and control combination device is speed-adjustment motor ’ s direct control unit. It can realize wide-range stepless speed adjustment by operating appointed potentiometer. DK-1B type controller (Fig 9.7) in TKZ series speed-adjustment and control combination device is speed-adjustment motor ’ s direct control unit. It can realize wide-range stepless speed adjustment by operating appointed potentiometer.

52. DK-1B can be equipped with ZC-1A operator to work as single set manual speed adjustment and control; be equipped with DDZ adjustor to work as single set automatic speed adjustment and control ; DK-1B can be equipped with ZC-1A operator to work as single set manual speed adjustment and control; be equipped with DDZ adjustor to work as single set automatic speed adjustment and control ;

53. be equipped with TC-1A co-operator and ZC-1A operator to realize multi-set synchronous or proportional running; and be combined with DDZ adjustor ZC-1A operator to realize multi-set automatic synchronous or proportional running. be equipped with TC-1A co-operator and ZC-1A operator to realize multi-set synchronous or proportional running; and be combined with DDZ adjustor ZC-1A operator to realize multi-set automatic synchronous or proportional running.

54. 3. Experiment material Relay-contactor Control of three-phase induction motor Relay-contactor Control of three-phase induction motor 1 Objectives –1. To be familiar with relay, contactor, and other controlling devices; –2. To understand the controlling circuits of three-phase induction motors.

55. 2 Apparatus and Equipments 2 Apparatus and Equipments The apparatus and equipments are listed in table 9.1. The apparatus and equipments are listed in table 9.1.

56. Table 9.1 The apparatus and equipments

57. 3 Approach of the Experiment 3 Approach of the Experiment 1. The direct starting of the three-phase induction motor 1. The direct starting of the three-phase induction motor (1) Be familiar with the structures of devices (see Fig 9.8) and their terminals. Distinguish the normal closed contacts and normal open contacts of the main contactor KM. Write down the data of the induction motor. (1) Be familiar with the structures of devices (see Fig 9.8) and their terminals. Distinguish the normal closed contacts and normal open contacts of the main contactor KM. Write down the data of the induction motor.

58. Fig 9.8 Experiment board for relay-contactor control

59. (2) Complete following experiment steps after finishing the circuit connection (Fig 9.9) (2) Complete following experiment steps after finishing the circuit connection (Fig 9.9) –Turn on the power supply (air-breaker Q) –Start the induction motor directly (button SB2) –Stop the motor by the button SB1

60. Fig 9.9 The direct starting of the three-phase induction motor

61. * Observe the operation of the contactor KM and the motor * Observe the operation of the contactor KM and the motor –Start the motor by button SB 2, then turn off the power supply by the air-breaker Q to stop the motor. –Turn on the power supply (air-breaker Q) again

62. * Observe the operation of the motor and understand low-voltage protection of the circuit. * Observe the operation of the motor and understand low-voltage protection of the circuit. –Intermittent operation: turn off the power supply (Q), remove the auxiliary contact connected between the modes a and b, turn on the power supply (Q) again, then operate the button SB 2

63. * Understand the function of the auxiliary contact acting as a self- locked contact. * Understand the function of the auxiliary contact acting as a self- locked contact.

64. 2. Rotating and inverse rotating of an induction motor 2. Rotating and inverse rotating of an induction motor The circuit is shown in Fig 9.10 The circuit is shown in Fig 9.10 * Observe the operation of the motor and understand the functions of the auxiliary contacts. * Observe the operation of the motor and understand the functions of the auxiliary contacts.

65. Fig 9.10 Rotating and inverse rotating of an induction motor

66. 4 Discussions 4 Discussions 1. Point out the protective functions in the circuit shown in Fig 9.10; 1. Point out the protective functions in the circuit shown in Fig 9.10; 2. Point out the self-locked contacts and inter-locked contacts; 2. Point out the self-locked contacts and inter-locked contacts; 3. Whether can the fuse and thermal overload relay replace each other? 3. Whether can the fuse and thermal overload relay replace each other?

67. This is the End of the Reading materials

68. Exercises Ready to go? Ready to go?

69. 1. Put the Phrases into English 1) 控制电路 1) 控制电路 2 ）磁场 2 ）磁场 3 ）其它因数 3 ）其它因数 4 ）线圈通电 4 ）线圈通电 5 ）关上阀门 5 ）关上阀门 Show the Answer

70. 1) control circuitry( 或 circuit) 1) control circuitry( 或 circuit) 2 ） magnetic field 2 ） magnetic field 3 ） other factor 3 ） other factor 4 ） energize the coil (with electric current) 4 ） energize the coil (with electric current) 5 ） shut valve 5 ） shut valve

71. 6 ）继电器线圈 6 ）继电器线圈 7 ）常闭触点 7 ）常闭触点 8 ）同时合上很多触点 8 ）同时合上很多触点 9 ）电动机 9 ）电动机 10 ）交流接触器 10 ）交流接触器 Show the Answer

72. 6 ） the relay coil 6 ） the relay coil 7 ） normally-closed contact 7 ） normally-closed contact 8 ） close many contacts at once 8 ） close many contacts at once 9 ） electric motor 9 ） electric motor 10 ） AC contactor 10 ） AC contactor

73. 2. Put the Phrases into Chinese 1 ） starting and stopping the motor 1 ） starting and stopping the motor 2 ） predetermined manner 2 ） predetermined manner 3 ） forward or reverse rotation 3 ） forward or reverse rotation 4 ） digital input signals 4 ） digital input signals 5 ） be oriented along the length of the coil 5 ） be oriented along the length of the coil Show the Answer

74. 1 ）启动 / 停止电动机 1 ）启动 / 停止电动机 2 ）预先设定的方法 2 ）预先设定的方法 3 ）正反转 3 ）正反转 4 ）数字输入信号 4 ）数字输入信号 5 ）沿着线圈的轴线方向 5 ）沿着线圈的轴线方向

75. 6 ） attracting an iron armature 6 ） attracting an iron armature 7 ） industrial relays 7 ） industrial relays 8 ） sit on a shelf 8 ） sit on a shelf 9 ） high-power load 9 ） high-power load 10 ） auxiliary contact 10 ） auxiliary contact Show the Answer

76. 6 ）吸引衔铁 6 ）吸引衔铁 7 ）工业继电器 7 ）工业继电器 8 ） 放在柜子 ( 或架子 ) 上 8 ） 放在柜子 ( 或架子 ) 上 9 ） 大功率负载 9 ） 大功率负载 10 ）辅助触点 10 ）辅助触点

77. 3. Sentence Translation 1) A motor controller is connected to a power source such as a battery pack or power supply, and control circuitry in the form of analog or digital input signals. 1) A motor controller is connected to a power source such as a battery pack or power supply, and control circuitry in the form of analog or digital input signals. 1 ）电动机控制器可以直接接在电池组上或 电源上，用模拟或数字输入信号控制（电 动机）电路。 1 ）电动机控制器可以直接接在电池组上或 电源上，用模拟或数字输入信号控制（电 动机）电路。

78. 2) The greater the current, the greater the strength of the magnetic field, all other factors being equal. 2) The greater the current, the greater the strength of the magnetic field, all other factors being equal. 2 ）在其他条件不变的情况下电流越大，则 磁场的强度越大。 2 ）在其他条件不变的情况下电流越大，则 磁场的强度越大。

79. 3) Relays are extremely useful when we have a need to control a large amount of current and/or voltage with a small electrical signal. 3) Relays are extremely useful when we have a need to control a large amount of current and/or voltage with a small electrical signal. 3 ）当我们要用一个小的电信号去控制大电 流或高电压时，继电器十分有用。 3 ）当我们要用一个小的电信号去控制大电 流或高电压时，继电器十分有用。

80. 4) It is quite likely that the current required to energize the relay coil will be hundreds of times less than the current rating of the contact. 4) It is quite likely that the current required to energize the relay coil will be hundreds of times less than the current rating of the contact. 4 ）给继电器线圈供电的电流是触点额定电 流的几百分之一。 4 ）给继电器线圈供电的电流是触点额定电 流的几百分之一。

81. 5) When a relay is used to switch a large amount of electrical power through its contacts, it is designated by a special name: contactor. 5) When a relay is used to switch a large amount of electrical power through its contacts, it is designated by a special name: contactor. 5 ）当继电器用于作为大电流的开关时，就 有一个指定的名称：接触器。 5 ）当继电器用于作为大电流的开关时，就 有一个指定的名称：接触器。

82. 4 ． Translation 1) Numerical control or numerically controlled (NC) machine tools are machines that are automatically operated by commands encoded on a digital medium. 1) Numerical control or numerically controlled (NC) machine tools are machines that are automatically operated by commands encoded on a digital medium.

83. NC machines were first developed soon after World War II and made it possible for large quantities of the desired components to be very precisely and efficiently produced (machined) in a reliable repetitive manner. NC machines were first developed soon after World War II and made it possible for large quantities of the desired components to be very precisely and efficiently produced (machined) in a reliable repetitive manner. Show the Answer

84. 数控机床是可以根据数字 ( 媒体中 ) 编码的指 令自动运行的机器。在第二次世界大战结 束后不久（人们）就设计制造出数控机床。 数控机床加工精确、效率高，有了它就可 以用一种（可靠且）重复的加工手段制造 出大量的 ( 机械 ) 部件。 数控机床是可以根据数字 ( 媒体中 ) 编码的指 令自动运行的机器。在第二次世界大战结 束后不久（人们）就设计制造出数控机床。 数控机床加工精确、效率高，有了它就可 以用一种（可靠且）重复的加工手段制造 出大量的 ( 机械 ) 部件。

85. 2) Apple iPod nano (Fig 9.11) 2) Apple iPod nano (Fig 9.11) Third Gen. Green (8 GB, MB253LL/A) Digital Media Player Third Gen. Green (8 GB, MB253LL/A) Digital Media Player

86. The larger, brighter display means amazing picture quality. It features an anodized aluminum top and polished stainless steel back. It'll wow you for hours. Play up to 5 hours of video or up to 24 hours of audio on a single charge. The larger, brighter display means amazing picture quality. It features an anodized aluminum top and polished stainless steel back. It'll wow you for hours. Play up to 5 hours of video or up to 24 hours of audio on a single charge.

87. iTunes provides music, movies, TV shows, games and more. All those features within a wafer-thin, 6.5-mm profile makes iPod nano a tiny big attraction you'll just love carrying around! iTunes provides music, movies, TV shows, games and more. All those features within a wafer-thin, 6.5-mm profile makes iPod nano a tiny big attraction you'll just love carrying around! Show the Answer

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89. This is the End of the Exercises Good work everyone !!! ( 习题答案仅供参考 )