Answer / aditya shirbavikar

Free wheeling diode (Fwd) is used in a d.c circuit, generally in a.c drives in which two stages are used to convert FFFV to VVVF. first rectification and then inversion. so, free wheeling diose is placed between rectifier bridge and invertor bridge so to prevent the reverse a.c pulses from blowing up the rectifier bridge circuit.

Answer / aj

simple u cannt break
inductive ckt. And coil is
essentially inductive so fw
diode is to used to make use
of inductive current when
switch is off.

Can u explain : what is supply for train (whether a,c or d.c ).I know that supply is 25000v a.c .But there is rumour that supply is D.C. And also explain how lights and fans inside the trains are working ,and what type of motors are used in trains whether D.C motors or induction motors .If d.c motor, how it gets supply.If traction motors are used then what are traction motors and its functions and how it differs from other motors and also explain about locomotive . please reply..............

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