What are the advantages of using a direct drive motor?
One of the major advantages of using direct drive motors is increased positional, speed and dynamic accuracy. Rather than dealing with a coupling, gearbox, belts or chains, a direct drive motor attaches directly to the load so there is no hysteresis, backlash or ‘lost motion’ in any direction of movement.
Which motor is usually used in DC system of traction?
Traditionally, these were series-wound brushed DC motors, usually running on approximately 600 volts. The availability of high-powered semiconductors (thyristors and the IGBT) has now made practical the use of much simpler, higher-reliability AC induction motors known as asynchronous traction motors.
What is the purpose of a traction motor?
The traction motor of EVs is responsible for converting electrical energy to mechanical energy in such a way that the vehicle is propelled to overcome aerodynamic drag, rolling resistance drag, and kinetic resistance.
Is Direct Drive washing machine better?
Direct drive washing machines have much more extended longevity and more features than your standard washer. When a repair occurs, finding a qualified technician can be somewhat more complicated. Also, the repairs behind this may be less frequent, but they are also far more expensive.
Which motor is used for traction work?
The motors used are induction or asynchronous motors designed to have characteristics suitable for traction. The speed and torque of the motor are controlled by varying the frequency, voltage and current applied to the stator coils. Motors for a typical locomotive would be in the range 400 to 600 kW.
Why is it called a traction motor?
Before the mid-20th century, a single large motor was often used to drive multiple wheels through connecting rods. This was the same way that steam locomotives would turn their drive wheels. … This is called a “nose-suspended traction motor”.
Which motor is used for train?
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.
Which traction system is best?
In case of heavy trains that require frequent and rapid accelerations, DC traction motors are better choice as compared AC motors. DC train consumes less energy compared to AC unit for operating same service conditions.
Which motor is used in tramway?
This paper compares five different motor types used in variable speed drives: a dc motor with a mechanical commutator and with electromagnetic or permanent magnets excitation, a cage induction motor, asynchronous cascade with a slip‐ring motor and a brushless motor with PM excitation.
Are locomotives AC or DC?
Rectifier locomotives, which used AC power transmission and DC motors, were common, though DC commutators had problems both in starting and at low velocities. Today’s advanced electric locomotives use brushless three-phase AC induction motors.
How does a traction converter works?
Traction Converter would have multiple line converters which convert single phase AC input to a stable DC link bus voltage. A combination of one or more inverters converts this DC bus voltage to 3-phase power controlling one or more traction motors each.
What are the requirements for traction motor control?
Thus, the general requirements of the traction motor drives can be summarized as follows: 1. high torque density and power density; 2. very wide speed range, including constant-torque and constant-power regions; 3.
Which method is best for series traction motor?
Explanation: Series-parallel control method is superior to the rheostatic control insofar as efficiency is concerned. However, it is limited to two speed steps. The method is commonly employed for speed control of series traction motors.