Commutation In Electronics

December 23, 2023 Post a Comment

Commutation in electronics

Commutation means transfer of current from one circuit to another.

What is commutation and its types?

One method of classification is as follows. 1 Natural Commutation or line commutation (class F) 2 Load Commutation or Self commutation (class A) @ Resonant - Pulse Commutation (class B) ↳ Complementary Commutation (class C)

What is meant by commutation circuit?

When an SCR moves in the mode of forwarding conduction, then its gate terminal loses its control. For that, some additional circuit should be used to turn off thyristor/SCR. So, this additional circuit is called a commutation circuit. So this term is mainly used for transferring the current from one ane to another.

What are commutation methods of SCR?

There are mainly two types of SCR commutation techniques: Natural Commutation and Forced Commutation.

How does a commutator convert AC to DC?

In a generator the commutator picks off the current generated in the windings, reversing the direction of the current with each half turn, serving as a mechanical rectifier to convert the alternating current from the windings to unidirectional direct current in the external load circuit.

Why is commutation needed?

The basic purpose of commutation is to ensure that the torque acting on the armature is always in the same direction. The voltage generated in the armature is alternating in nature, and the commutator converts it to direct current.

What is an example of commutation?

commutation, in law, shortening of a term of punishment or lowering of the level of punishment. For example, a 10-year jail sentence may be commuted to 5 years, or a sentence of death may be commuted to life in prison.

What are the two methods of commutation?

There are mainly two techniques for Thyristor Commutation: Natural and Forced. The Forced commutation technique is further divided into five categories which are Class A, B, C, D, and E.

Which commutation is best?

Detailed Solution. For high output power where load fluctuation is not high, voltage commutated chopper is commonly used for the best performance.

What is current and voltage commutation?

Current commutation-SCR is turned off by reducing anode current below holding current. • Voltage commutation-SCR is turned off by applying large reverse voltage across it. Classification of Forced Commutation Methods.

Why commutator is used in DC generator?

The commutator on the DC generator converts the AC into pulsating DC. The commutator assures that the current from the generator always flows in one direction. The brushes ride on the commutator and make good electrical connections between the generator and the load.

How can we reduce commutation?

Methods of Improving Commutation

Resistance Commutation.
Voltage Commutation.
Brush Shift.
Commutating Poles or Interpoles.
Compensating Windings.

What is the type of commutation used?

Load commutation or self commutation is used in inverter in which L and C are connected in series with the load or C in parallel with the load such that the overall load circuit is underdamped.

What is commutation rectifier?

Commutation is the process when conduction switches from one supply phase to another. Commutation overlap occurs when there is inductance in the supply circuit of a diode (or thyristor) rectifier. It can be seen by adding a supply inductance to the 3-phase supply in the diode rectifier simulation.

Why commutator is not used in AC?

The main purpose of commutator is only to convert Ac to DC or vice versa, But in case of alternaters Commutator is not required because output will be AC only not DC. In case of DC generators Generation is AC so by using commutator will convert the AC to DC.

What is the principle of commutator?

A commutator is a rotatory electrical switch that reverses the direction of current between the rotor and the external circuit periodically. The reversal of the current each half-turn gives rise to a steady rotating torque.

Can DC motor run without commutator?

No, a direct current motor cannot run without a commutator because there is no induced electromotive force inside the armature. The commutator plays the function of supplying current to the armature from the brush. That is why the armature removed will not supply the motor. Further, it will stop the running.

Is commutator convert DC to AC?

Hence, the commutator converts AC to DC.

What happens during commutation?

The currents induced in the armature winding of a DC generator are alternating in nature. The action of commutator (called commutation) involves the change from a generated alternating current to a direct current.

How does a commutator reverse the current?

The split ring commutator reverse the current in the armature every half revolution when the commutator changes contact from one brush to another. This reverse in current causes the forces acting on the coil to be reversed. This helps the coil continue to rotate in a clockwise direction.