why do we use ac motors for tower crane?
AC motors are used in tower crane due to following- 1. Availability of power. Generally power distribution by state utility is AC only.For DC motor one has to provide AC -DC converter...involving an extra cost without any extra advantage. 2. Crane motors require high starting torque..In slip ring induction motor (used for cranes) this can be achieved by adding resistance in rotor circuit. 3. In the latest technology, for energy efficient use, variable voltage variable frequency drives are used. This technology is possible with AC only.
1) Availability of AC power 2) Clean, quiet, efficient 3) size does not matter!! AC motors are larger than a comparible hydraulic motor, but on a tower crane, SIZE DOES NOT MATTER.
we use AC motors because they're simple, have the fewest moving parts, and last the longest.
