Which type of DC motor is used in trains?
Answer: Series-wound DC motors. That means current flows through the armature, then through the fields. They have high starting torque, favorable for starting a train.
Which system is used in trains AC or DC?
Railway electrification systems using alternating current (AC) at 25 kilovolts (kV) are used worldwide, especially for high-speed rail.
Are trains electric or diesel?
A few passenger rail lines have been converted to electric power in the United States (Amtrak’s Northeast corridor and Harrisburg, PA, line), but the rest of passenger rail and all of freight rail is diesel-powered.
Where is DC series motor used?
Series DC motors are generally used where high starting torque is required, and speed variations are possible. These types of direct connection motors are, for instance, used in the traction system, cranes, air compressors, vacuum cleaners, sewing machines, etc.
Why are DC motors used?
DC motors develop full torque at low speed and across the full operating range from zero to base speed (see Figure 1). This makes DC motors a good choice for driving constant-torque loads – such as conveyor belts, elevators, cranes, ski lifts, extruders and mixers.
What is the speed of DC motor?
DC controls adjust speed by varying the voltage sent to the motor (this differs from AC motor controls which adjust the line frequency to the motor). Typical no load or synchronous speeds for an AC fractional horsepower motor are 1800 or 3600 rpm, and 1000-5000 rpm for DC fractional hp motors.
Why is DC preferred over AC?
Hence, the voltage through transmission lines is very high, which reduces the current, which in turn minimizes the energy lost through transmission. This is why alternating current is preferred over direct current for transmitting electricity, as it is much cheaper to change the voltage of an alternating current.
Do trains use electric motors?
Diesel Locomotives use electricity to drive forward motion despite the name ‘diesel’. A large diesel engine turns a shaft that drives a generator which makes electricity. This electrical energy powers large electric motors at the wheels called ‘traction motors’.
Which current is used in railway?
Indian railway traction system uses 1.5 kV DC around Bombay and 25Kv ac is used in rest of the country. The supply for traction system is taken from state utility which is three phase source at 132/220 kV.