有關感應電動機的中英對照翻譯

1、<p>　　感應電動機的基本工作原理可以旋轉(zhuǎn)馬蹄形磁鐵和銅圓盤的實驗來說明。當馬蹄鐵磁鐵旋轉(zhuǎn)時，穿過銅圓盤的移動磁場在盤中感應出渦旋電流。這些渦旋電流的方向能夠引起圓盤跟隨馬蹄形磁鐵旋轉(zhuǎn)。根據(jù)右手定則將會產(chǎn)生渦旋電流。</p><p>　　右手定則指出：伸出右手的大拇指、食指、中指，并讓他們互相垂直，這樣實質(zhì)的方向為磁場方向，大拇指指向為導體運動方向，中指的方向為感應電壓的方向。注意，導體的相對運動方向

2、和磁場旋轉(zhuǎn)的方向相反。</p><p>　　運用左手定責得出銅盤受到得力與磁鐵旋轉(zhuǎn)方向一致。左手定則指出：伸出左手的大拇指、食指、中指，并令他們互相垂直，讓食指指向磁場方向，中指指向電流的方向，則大拇指的方向即為作用力的方向。</p><p>　　盡管銅盤將按照旋轉(zhuǎn)磁場的方向運動，但它決不會與磁場的速度相同。因為如二者速度相同，它們之間將不存在相對運動，從而銅盤中也就沒有感應電流產(chǎn)生。旋轉(zhuǎn)

3、磁場和銅盤間的速度之差稱為轉(zhuǎn)差率。轉(zhuǎn)差率對于感應式電動機的工作至關重要。在感應電動機中，旋轉(zhuǎn)磁場是由定子中的繞組激發(fā)的，感應電流是在轉(zhuǎn)子中流動的，旋轉(zhuǎn)馬蹄磁鐵和銅圓盤在結(jié)構上與當今的感應式電動機有很大區(qū)別，但是它們基本原理上是相同的。</p><p>　　旋轉(zhuǎn)磁場對感應式電動機是至關重要的。實際電機中，它是通過空間上交替布置繞組和時間相位上相互交替的激勵電壓實現(xiàn)的。</p><p>　　轉(zhuǎn)

4、子是采用層疊的鋼片沖壓而成的，轉(zhuǎn)子繞組有疊片上沖槽內(nèi)嵌入的導體條構成。這寫導體條在兩端通過短路環(huán)構成短路。不包括層疊片式鐵心中鑄入鋁的方式構成轉(zhuǎn)子。在較大功率的交流電機中，鑄鋁轉(zhuǎn)子不實用，采用的是在轉(zhuǎn)子槽中插入鋼條的作法。這些鋼條在兩端通過銅短路環(huán)短路，短路環(huán)是采用纖接或焊接的方式與銅條相連的。有時采用青銅或其他合金代替銅來制作鼠籠和短路環(huán)。到底在多大功率上，以銅轉(zhuǎn)子代替鑄鋁轉(zhuǎn)子因不同的制造商而不同名的是幾千馬力以上的電動機轉(zhuǎn)子一般都采

5、用條形工藝。</p><p>　　另一個與電動機容量有關的結(jié)構特性是所采用的線圈組的類型。在中小型交流電動機中，大多數(shù)線圈是散繞的。這些線圈采用的是圓截面導線，這些導線繞置在定子槽中，并將其端部繞置成菱形。只不過雜給定繞組中導線是隨即分布的，因此得名“散繞”。對于大型交流電動機尤其是高壓電動機，如2300V以上的電動機，則采用模繞線圈。這些線圈采用截面為矩形的導線構成，將它們彎曲成型后纏上絕緣帶。在制作定子繞組時

6、，線圈被做成適當?shù)某叽?，以便將整個線圈置于定子槽中。模繞式線圈可用作高壓線圈，因為它較容易在將繞組置于定子之前為每個線圈采用額外的絕緣措施。</p><p><b>　　Motor</b></p><p>　　The basic principe of operation of an induction machine in illustrated by the re

7、volving horsesshou-magnet and copper-disk experiment pictured in Fig 1-1.When the horseshou magnet is rotated，the moving magnetic field passing across the copper disk induces eddy currents in the disk.These eddy currents

8、 are in such a direction as to cause the disk to follow the rotation of the horseshoe magnet.With the direction of rotation shown in the figure，the eddy cyrrents will be as displayed to Fleming’s righ</p><p>

9、;　　Fleming’s right-hand rule：Place the thumb and the first and second fingers of the right hand so that all three are mutually perpendicular.With the hand in this position，the first finger in pointed in the direction of

10、the field，the thumb is in the direction of motion of the conductor， and the second finger is in the direction of the induced voltage.Note that the relative motion of the conductor is opposite to the direction of rotation

11、 of the magnetic field.</p><p>　　By applying Fleming’s left-hand rule，the force on the copper disk is determined to be in the direction of rotation of the magnet.</p><p>　　Fleming’s left-hand ru

12、le：Place the thumb and the first and second fingers of the left hand so that all three are mutually perpendicular to each other.With the first finger in the direction of the field and the second finger in the direction o

13、f the current，the thumb indicates the direction of the force.</p><p>　　Whereas the copper disk will rotate in the same direction as the rotating magnetic field，it will never reach the same speed ad the rotat

14、ing magnet，because if it did，there would be no relative motion between the two and therefore no current induced in the copper disk.The difference in speed between the rotartng magnetic field and the copper disk is known

15、as slip，which is essential to the operation of an induction motor.In induction motors the rotating magnetic field is set up by windings in the s</p><p>　　The rotating magnetic field is essential to the funct

16、ioning of an induction motor.In practical machines this rotating magnetic field is achered by a combination of a space displacement of the winding and a time-phase displacement of the exciting voltage.</p><p&g

17、t;　　The rotor is formed from laminated electrical steel punching，and the rotor winding consists of bars contained in slots punched in the laminations.These bars are short-circuited at both ends by a short-circuiting ring

18、.A bar-end ring structure，without the laminated core，is called a squirrel cage.In small-and medium-horsepower sizes，rotors are made by casting aluminum into the rotou core，in the larger sizes of ac motors，cast-aluminum r

19、otors are not pratical，and copper bars are inserted into rotor s</p><p>　　Another construction feature dependent in motor size is the type of coil winding used.In small and medium-size ac motors，most coils a

20、re random-wound.These coils are made with round wire，which is wound into the stator slots and assumes a diamond shapr in the end turns； however， the wires are randomly located within a given coil，and hence the name “rand