Answer / raghavendra

its not ac series motor but it is the DC SERIES motor which is used for traction and for variable speed mechanisms because of its HIGH STARTING TORQUES. The main applications of this is in train engines

Answer / binod

FOR HIGH TORQUE

Answer / robert d barnett

I'm not really certain that a.c.series motors ARE preferred for electric
traction. It depends on the situation. There are of course, both AC and DC series motors which are virtually the same. The difference is the inductive reactance of the series field when supplied with AC requires design steps to be taken to correct for this phenomenon. The advantage of using AC is the simplicity of the supply system for long distance systems. A transformer could be put on board the locomotive to reduce the transmission voltage (typ 11,000V) to motor voltage. A DC motor is a similar size rail network would require a substation with a transformer and some means of rectification to DC plus the control system and inherent maintenance costs. It's a bit of a simplification but trolley lines and most interurbans were DC and electric railroads were AC.

Answer / pawan thakur

Bcoz of High troque and also ac supply direct given in series ac. Motor in case of dc motor ac. Supply convert in dc.. Is more expensive..nd switching controling handling is easy to Ac.

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