A step down chopper is to be used to supply power from 600 overhead wire to commutator motor on a trolley bus . The motor may be modeled as a generated direct voltage in series with a resistance of .2? and inductance of 25mH. The frequency of the chopper is set at 500 Hz.
1-When the bus is stopped , what should be the ON time of the chopper to provide a motor current of 150 A ?
2-What is maximum possible generated voltage of the motor for which a current of 150 A can be supplied ?
3-What is the average value of the supply current for the conditions of 1 and 2