What is thyristor in speed control?
The controlled (thyristor) rectifier provides a low-impedance adjustable ‘d.c.’ voltage for the motor armature, thereby providing speed control. … The generator was driven at fixed speed by an induction motor, and the field of the generator was varied in order to vary the generated voltage.
Which device can be used to control the speed of a motor?
Motor Controllers and Drives are electrical or electronic devices that regulate motor speed, torque, and position outputs. The drive modifies the power input to the motor to achieve the desired output.
Which is the most popular speed control method of DC motor?
Another one uses an AC motor driven Generator to provide variable voltage to the armature (named as Ward-Leonard System). Apart from these two techniques, the most widely used technique is the use of pulse width modulation to achieve speed control of a DC motor.
What is the most common method of controlling the speed of an AC motor?
The most common way of controlling AC motor speed is changing the motor’s frequency. With this method, variable speed AC motor drives are used to adjust the speed. These are often called variable frequency drives (VFD), AC inverters, or adjustable speed drives (ASD).
For which type of motor drives are thyristor converters still used?
Initially saturable reactors were employed in conjunction with high power silicon rectifiers for dc drives. Nowadays, thyristors are extensively used for ac-to-dc conversion. General Configuration of a Motor Drive: Figure 3.2 shows a block diagram illustrating the control of a motor drive.
What do you know about thyristor?
A thyristor is a four-layer device with alternating P-type and N-type semiconductors (P-N-P-N). … The primary function of a thyristor is to control electric power and current by acting as a switch.
What are the various methods used to control the speed of DC motor?
There are three main ways to achieve speed regulation in series DC motors–flux control, voltage control, and armature resistance control. In the flux control method, a rheostat (a type of variable resistor) is connected in series with the field windings.
Which is a better method to control motor speed Mcq?
DC Motor Speed Control MCQ Question 1 Detailed Solution
We can control the speed by increasing armature resistance. This method gives only below base speeds. This method is a constant torque and variable power drive.
Where are methods of speed control used?
Speed control methods of DC motor
- Flux control method. It is already explained above that the speed of a dc motor is inversely proportional to the flux per pole. …
- Armature control method. …
- Voltage Control Method. …
- Flux control method. …
- Variable resistance in series with armature. …
- Series-parallel control.
Which method is best suited for speed control and give few applications?
Table 1- Motor starting methods summary
|Reduced-Voltage Resistor or Reactor||High output torque vs. starting current|
|Wye-Delta||Relatively low inrush current Relatively simple starter construction Good for long acceleration times|
|Part-Winding||Relatively Simple starter construction|
Which method can be used to obtain speed greater than the rated speed of the motor?
By varying flux, we can increase the speed more than its base speed. This method is constant power and variable torque drive.