The universal motor is a type of electric motor that can operate on either AC or DC power and uses an electromagnet as its stator to create its magnetic field. It is a commutated series-wound motor where the stator’s field coils are connected in series with the rotor windings through a commutator.
How does universal motor works on both AC and DC?
For proper operation with AC supply, a universal motor incorporates a compensation winding, in series with the armature and field winding. When the motor runs on AC voltage, the alternating flux causes a reactance voltage, which limits the current to a much lower level than would be produced with DC voltage.
What is difference between AC and universal motor?
In the AC series motor, the armature and field are still wound and interconnected just as in the DC series motor. … Given the same voltage, a universal motor will have higher speeds on DC supply than on AC supply because of the voltage drop that exists on AC supply.
How does a universal motor start?
Working of universal motor
When current flows in the field winding, it produces an electromagnetic field. … When a current carrying conductor is placed in an electromagnetic field, it experiences a mechanical force. Due to this mechanical force, or torque, the rotor starts to rotate.
What are the advantages of universal motor?
Universal motors have high starting torque, can run at high speed, and are lightweight and compact. They are commonly used in portable power tools and equipment, as well as many household appliances. They’re also relatively easy to control, electromechanically using tapped coils, or electronically.
What is the principle of universal motor?
working principle of universal motor
The working principle of the universal motor is like a DC series generator. When the current flows into the field winding, it generates an electric field. The same current is still emanating from the armature conductors.
Which motor is used as an universal motor?
The motors which can be used with a single phase AC source as well as a DC source of supply and voltages are called as Universal Motor. It is also known as Single Phase Series Motor. A universal motor is a commutation type motor.
How do you control the speed of a universal motor?
Three methods of controlling the speed of a universal electric motor were discussed. These are the resistance control method, the field tapping method, and the centrifugal switch method. In the resistance control method, a variable resistance in series with the motor is used to set the RPM.
Can a DC motor run on AC?
DC cannot produce varying flux as it is constant and uni directional. But DC motors may run on AC supply . The DC series motor can run on both AC &DC supply . It is also called as an Universal motor.
What is the another name of universal motor?
This is a type of AC commutator motor. Although mainly used on single-phase AC, it rotates on both AC and DC power. It is also called a “universal motor” or “commutator motor”. Its major applications are electric vacuum cleaners, power tools, and juicers.
What is the working principle of hysteresis motor?
A hysteresis motor works on the principle of hysteresis losses (it is a loss occurred due to magnetization and demagnetization of the material depending on the direction of flow of current). A motor is an electrical device that converts electrical energy into mechanical energy.
Why compensating coil is required in a universal motor?
A compensation winding in a DC shunt motor is a winding in the field pole face plate that carries armature current to reduce stator field distortion. Its purpose is to reduce brush arcing and erosion in DC motors that are operated with weak fields, variable heavy loads or reversing operation such as steel-mill motors.
How do you change the rotation of a universal motor?
The direction of rotation of a universal motor can be changed by either: (i) Reversing the field connection with respect to those of armature; or (ii) By using two field windings wound on the core in opposite directions so that the one connected in series with armature gives clockwise rotation, while the other in …
Why capacitor is used in universal motor?
Some single-phase AC electric motors require a “run capacitor” to energize the second-phase winding (auxiliary coil) to create a rotating magnetic field while the motor is running.