It is required to design the DC motor dedicated to carry two wagons underground railway train. Each wagon is supposed to carry a maximum of 20 persons. The power utility is supplying the railway by 700 V DC source capable to deliver enough current. The train should reach a full load speed of 100 Km per hour. The efficiency of the motor must be between 85 to 90 percent. The motor shaft diameter range is (0.6 to 0.8 m)
Choose and estimate all the design characteristics of the motor finally display all the power flow diagram results including efficiency and speed regulation of the motor. Give all assumptions taken.