DC (Direct Current) motors have traditionally been recommended for use in trains for a wide range of reasons, however it is important to remember that there is an increasing preference toward the usage of AC (Alternating Current) motors in current train systems.
Why do trains utilize DC motors?
DC motors are employed in trains due to their high torque & excellent speed control. DC motors, as opposed to AC motors, may provide industry applications with an appropriate balance of high starting torque and adjustable speed, resulting in seamless yet precise performance. Trains are large-scale applications; thus, a DC motor can effectively & safely carry the heavy load ahead.
DC motors are additionally a great option for train windshield wipers, a difficult application that needs to be capable of operating in a wide range of conditions. A decent windscreen wiper motor must function properly at any speed, regardless of the weather. This requires accurate speed control, allowing them to respond smoothly & easily to changing conditions.
What are the advantages of DC motors?
DC motors have numerous advantages, making them an ideal alternative to be utilized on trains around the world.
1). Excellent speed control
2). Smooth operation
3). High Torque
4). Control & Traction Characteristics
5). Ease of Reversing
6). Regenerative Braking
7). Simplicity and maintenance:
1). Excellent speed control
DC motors are noted for their excellent speed control, providing the precision & safety that trains demand. Changing the armature (or) field voltage allows for a wide range of speed variations.
2). Smooth operation
DC motors can offer the requisite speed and power in a variety of applications, including trains. Trains, as an essential mode of transportation, should be able to start & stop quickly in order to save time and in the event of an emergency.
3). High Torque
DC motors have considerable high torque, making them ideal for big loads like trains. This implies that the motor can deliver an uninterrupted supply of power over extended periods of time, which is perfect for trains that run for more than 12 hours a day.
4). Control & Traction Characteristics
DC motors offers good control qualities, particularly at low speeds. This is essential for the trains during the acceleration, deceleration, & starting from a stopped position. DC motors provide smooth speed control in these kinds of applications.
5). Ease of Reversing
DC motors have the natural ability to easily reverse direction by changing the polarity of applied voltage. This feature is useful in train operations, allowing for simple and efficient control of both forward & reverse movements.
6). Regenerative Braking
DC motors can conduct regenerative braking, which converts kinetic energy back into electrical energy as the train slows down. This energy can be returned to the power system (or) utilized further in the train system.
7). Simplicity and Maintenance
DC motors are comparatively simple to construct & require less maintenance than some AC motor systems. DC traction motors used to be popular in trains due to their simplicity.
AC vs DC-what’s the difference? – Locomotives
However, with technological breakthroughs & the advancement of power electronics, AC traction motors are now increasingly widespread in modern train systems. AC motors have several advantages, including enhanced efficiency, lower maintenance requirements, & better performance at higher speeds. Furthermore, advances in control systems, including variable frequency drives, have improved the capacity to successfully control alternating current motors.
FAQ
Why are DC motors used in trains and not AC motors?
DC motors are used on trains is because of their high torque and good speed control. Compared to AC motors, DC motors can provide industry applications with a fine balance of strong starting torque and controllable speed for seamless yet precise performance
Why is AC better than DC for trains?
AC traction for locomotives is a major improvement over the old DC systems. The primary advantages of AC traction are adhesion levels up to 100% greater than DC and much higher reliability and reduced maintenance requirements of AC traction motors
Why do we use a DC motor instead of an AC motor?
AC motors are generally considered to be more powerful than DC motors because they can generate higher torque by using a more powerful current. However, DC motors are typically more efficient and make better use of their input energy
Why use DC motors over AC motors?
They can Easily Control Speed
Unlike most AC motors in the market, DC motors are capable to control speed above/below the rated levels. For example, the DC shunt motors are easy to vary the speed safely. This means that they can be used on a wide range of applications
Do model trains use AC or DC?
Model Train Current Flow
Z, N, HO, OO, some O, and G scale locomotives for the most part use DC current and are able to reverse the locomotive direction by using a switch on the power supply to reverse the direction of the current flow on the rails like pictured here
Why is DC preferred over AC?
A big advantage of direct current is that it is easier to change the speed of a DC electric motor than it is for an AC one. This is useful in many applications, such as electric and hybrid cars
Why is DC more safe than AC?
How Dangerous is DC Current? If you compare AC to DC, then studies indicate that AC is around five times more dangerous. The human body is naturally more resistant to DC than AC and it has been proven that letting go – therefore escaping the impact of electrical shock – of live parts in a DC circuit is easier
