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渣漿泵電動機的選擇
1.電動機的型式和選擇
    電動機常用的形式有三相交流鼠籠型異步電機、三相交流繞線式異步電機、三相同步電機及直流電機等。
    (1)三相交流鼠籠型異步電機。它具有結構簡單、運行可袋、 維護方便、價格便宜、體積小等優點，但啟動性能差、不能調速、空載時功率因數低，但配備變頻設置或其他調速型式后，也可實現調速。三相交流鼠籠型異步電機目前使用得最普遍，在無特殊要求的情況下一般都采用它。

(2)三相交流繞線式異步電機。它具有能調速、啟動轉矩大、改善功率因數、大功率、高效率、轉速穩定等方面的優點，但它需電刷滑環或整流器等部件，相對于鼠籠型電機維護麻煩，價格也稍貴，并且隨負荷轉矩的增加，電機轉速將顯著下降。
    (3)同步電機。負載轉矩在允許限度內變化時，具有轉速能保持恒定，功率因數可調節等優點，但它需有專門的勵磁系統，結構較復雜，造價高，維護量大，安全性也不如鼠籠電機，所以常用于需要轉速保持恒定、低轉速、 大容量的泵中選用。
    (4)直流電機。僅用于有直流電源或設備的情況下，它需備有事故電池組，功率不大、轉速不高的特殊場合才選用。渣漿泵

Selection of slurry pump motor

1. Type and selection of motor

The common forms of motor are three-phase AC squirrel cage asynchronous motor, three-phase AC wound asynchronous motor, three-phase synchronous motor and DC motor.

(1) three phase AC squirrel cage asynchronous motor. It has the advantages of simple structure, baggable operation, convenient maintenance, low price, small volume, etc., but it has poor starting performance, no speed regulation, low power factor when no-load, but it can also achieve speed regulation when equipped with frequency conversion settings or other speed regulation types. At present, three-phase AC squirrel cage asynchronous motor is widely used, which is generally used without special requirements.

(2) three phase AC wound asynchronous motor. It has the advantages of speed regulation, high starting torque, improvement of power factor, high power, high efficiency, speed stability, etc., but it needs components such as brush slip ring or rectifier, which is more difficult to maintain than squirrel cage motor, and the price is also slightly expensive, and with the increase of load torque, the speed of electric machine will significantly decrease.

(3) synchronous motor. When the load torque changes within the allowable limit, it has the advantages of constant speed, adjustable power factor, etc., but it needs a special excitation system, which is more complex in structure, high in cost, large in maintenance, and less safe than the squirrel cage motor, so it is often used in pumps requiring constant speed, low speed and large capacity.

(4) DC motor. Only when there is DC power supply or equipment, it needs to be equipped with emergency battery pack. It can be used in special occasions with small power and low speed. Slurry pump