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Which of the following statements are correct for synchronous motors? 1. Synchronous motors are well-suited for direct connection top reciprocating compressors. 2. Over-excited synchronous motors are most commonly used for power factor improvement. 3. Synchronous motors are generally used for current regulation of long transmission lines Select the correct answer using the code given below.

Which of the following statements are correct for synchronous motors? 1. Synchronous motors are well-suited for direct connection top reciprocating compressors. 2. Over-excited synchronous motors are most commonly used for power factor improvement. 3. Synchronous motors are generally used for current regulation of long transmission lines Select the correct answer using the code given below. Correct Answer 1 and 2 only

Applications of Synchronous motors:

  • The important characteristics of the synchronous motor is its constant speed irrespective of the load conditions and variable power factor operation.
  • Due to constant speed characteristics, it is used in machine tools, motor generator sets, synchronous clocks, stroboscopic devices, timing devices, belt driven reciprocating compressors, fans and blowers, centrifugal pumps, vacuum pumps, pulp grinders, textile mills, paper mills line shafts, rolling mills, cement mills etc.
  • Over-excited synchronous motors draw leading current and hence acts as synchronous condenser. So, they are used to improve the power factor and to improve the voltage regulation.
  • Synchronous motors are generally used for voltage regulation of long transmission lines but not the current regulation.

 

Therefore, statement 1 and 2 are true.

Related Questions

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