Question: Which Motor Is Used For Constant Speed Application?

Which motor is not used for traction system?

DC shunt motors are not suitable for traction purpose, the reasons are given below: 1.

The dc shunt motor is a constant speed motor and its speed-torque characteristic does not meet with the requirements of traction.

i.e., the power drawn from supply mains varies directly as the load torque..

How do you slow down an electric motor?

Most DC motors can be slowed down by reducing the supply level of power, Volts, lower volts and resulting less amps, will create less electrical field and will slow motor down. For more gradual speed control there are electronic solutions that are called PWM (Pulse Width Modulation) controllers or Mosfet H bridges.

Which motor is more powerful AC or DC?

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.

What are the disadvantages of DC motor?

Disadvantages of DC motorsHigh initial cost.Increased operation and maintenance cost due to the presence of commutator and brush gear.Cannot operate in explosive and hazard conditions due to sparking occur at brush (risk in commutation failure)Oct 20, 2017

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.

What are the applications of motor?

The applications of electrical motor include the following. The applications of electrical motor mainly include blowers, fans, machine tools, pumps, turbines, power tools, alternators, compressors, rolling mills, ships, movers, paper mills.

Which motor is used for constant speed?

DC shunt motorHence, a DC shunt motor is able to self-regulate its speed, and can be referred to as a constant speed motor.

Which motor is used in traction?

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.

What are the characteristics of dc motor?

Generally, three characteristic curves are considered important for DC motors which are, (i) Torque vs. armature current, (ii) Speed vs. armature current and (iii) Speed vs. torque.

Which type of motor has high starting torque?

DC motorDC motor has high starting torque.In a series motor the same current flows through the armature and the field winding.

Are diesel locomotives AC or DC?

In a diesel–electric locomotive, the diesel engine drives either an electrical DC generator (generally, less than 3,000 horsepower (2,200 kW) net for traction), or an electrical AC alternator-rectifier (generally 3,000 horsepower (2,200 kW) net or more for traction), the output of which provides power to the traction …

How do you increase motor speed?

Increasing the speed can be achieved by increasing the supply frequency as the speed and frequency are directly proportional; however, there are two constraints.

What are the types of DC motor?

There are 4 main types of DC motors:Permanent Magnet DC Motors. The permanent magnet motor uses a permanent magnet to create field flux. … Series DC Motors. In a series DC motor, the field is wound with a few turns of a large wire carrying the full armature current. … Shunt DC Motors. … Compound DC Motors.Jul 5, 2017

Which motor is best for speed control?

induction motorThere are three speed control motor product groups. The “AC speed control motor unit” that uses the most popular single-phase capacitor-run induction motor, the small and highly efficient “Brushless DC motor unit”, and the “Inverter unit” that combines a three-phase induction motor with a small inverter.

Which starting method is best method in induction motor?

The direct on line starter method, of an induction motor is simple and economical. In this method, the starter is connected directly to supply voltage. By this method small motors up to 5 kW rating is started to avoid the supply voltage fluctuation.

Which DC motor has maximum self loading property?

Which DC motor has got maximum self-loading property? Explanation: A differentially compound DC motor, flux reduces so sharply at small increase in load at higher values of load. It is advisable that motor should not be used beyond some load value, as it may damage itself by self-loading. 5.

Which motor has high starting current?

Induction MotorStarting Current in Induction Motor: Starting current of induction motor is as high as 5 to 7 times the normal full load current.

Are locomotives AC or DC?

Modern AC locomotives tend to have better traction and offer better adhesive to the tracks than earlier models. AC diesel-electric trains are most commonly used for carrying heavier loads. However, DC diesel-electric trains are still very popular as they are relatively cheaper to manufacture.

Which DC motor is preferred for constant speed application?

9. Which motor has almost replaced DC shunt motor from its applications? Explanation: Owing to the relative simplicity, cheapness and ruggedness of the squirrel cage induction motor, the shunt motor is less preferred for constant-speed drives except at low speeds.

What is application of DC motor?

Applications. DC motors are suitable for many applications – including conveyors, turntables and others for which adjustable speed and constant or low-speed torque are required. They also work well in dynamic braking and reversing applications, which are common in many industrial machines.