In case of DC, DC Shunt Motor, and in case of AC, Squirrel Case Induction motor has good speed regulation!
Which motor has a poor speed regulation?
The speed regulation of a DC motor is defined as the change in speed from no load to full load. It is expressed as a fraction or a percentage of the full load speed. No load speed of a DC series motor is very high. So, it has poorest speed regulation.
For which motor the speed can be controlled?
The controlling of armature resistance controls the voltage drop across the armature. With this method, the speed of the DC motor can control. This method also uses a variable resistor in series with the armature. When the variable resistor reaches its minimum value, the armature resistance is at normal one.
Which DC motor has negative speed regulation?
Explanation: In differential compound motors flux will reduce as load is increased because series flux opposes shunt field flux. This will increase speed upon addition of load. Therefore, it has negative speed regulation means speed will increase due to increase in load.
Which DC motor is preferred for constant speed?
Which D.C motor is preferred for machine tools? Explanation: DC shunt motor is a constant speed motor tool machine such as lathe machine requires being run at a constant speed.
What is speed control of DC motor?
Speed Control of DC Motor (Shunt, Series, and Compound) Often we want to control the speed of a DC motor on demand. This intentional change of drive speed is known as speed control of a DC motor. Speed control of a DC motor is either done manually by the operator or by means of an automatic control device.
Which motor has widest variety of methods for speed control?
Has relatively wider range of speed control.
- A. Synchronous motor.
- Ship ring induction motor.
- Squirrel cage induction motor.
- D.C. shunt motor.
How do you slow the speed of a 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 most suitable for good starting torque?
Series wound DC motors are best for applications that require high startup torque, without the need for speed regulation. Like a shunt motor, as a load is applied to a DC series motor, the motor speed decreases, which reduces the back EMF and increases the net voltage.
Which motor is most suitable for good starting torque and constant speed?
1. Permanent Magnet Motors. The permanent magnet motor uses a magnet to supply field flux. Permanent magnet DC motors have excellent starting torque capability with good speed regulation.
Which speed control is used for getting the speed below rated speed?
Explanation: The drawback of armature speed control method is we get only speeds which are below the rated speed. As the value of series resistance increases, back emf decreases which result in lowering of the speed.
Which DC motor is preferred for elevators?
DC cumulative compound motor having high starting torque up to 450% depending upon the degree of compounding. The speed regulation is varying up to 25 ~ 30%. That’s why these motors are used in elevators.
Why is the DC motor preferred over AC motor?
D.C. motor is preferred over an A.C. motor when we need variable speed operation because As in DC series motor field winding and armature winding is in series. So whenever armature current changes field current also changes as they are same due to which its torque changes rapidly and we get a variable speed.
Which of the following motors has the highest no load speed?
No-load speed of which of the following DC motor will be highest? Explanation: At no load, armature current tends to zero, flux φ tends to zero, where speed is inversely proportional to the flux, speed will tend to infinity. Thus, no load speed of DC series motor is highest.