# What Is The Need Of Commutation?

## 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 the meaning of commutation?

the act of substituting one thing for another; substitution; exchange. the changing of a prison sentence or other penalty to another less severe. the act of commuting, as to and from a place of work.

## What is current commutation?

Commutation is the process of switching current in the phases in order to generate motion. … When current is applied to the motor, the correct winding is energized by virtue of the brushes being in contact with the commutator at the point where the winding terminates.

## What is resonant pulse commutation?

Class-B or Resonant Pulse Commutation is a forced commutation technique to turn off an SCR. In this technique, thyristor or SCR is turned off by gradual build-up of resonant current in the reverse direction i.e. from cathode to anode of SCR. … Now, at t=0, the main thyristor / SCR is gated and turned on.

## How is thyristor turned off?

Thus, a thyristor behaves like a normal semiconductor diode after it is turned on or “fired”. The GTO can be turned on by a gate signal, and can also be turned off by a gate signal of negative polarity. … Turn off is accomplished by a “negative voltage” pulse between the gate and cathode terminals.

## What are the types of commutation?

Forced Commutation of SCR:Class-A Commutation (also known as Load Commutation)Class-B Commutation (also known as Resonant Pulse Commutation)Class-C Commutation (often called Complimentary Commutation)Class-D Commutation or Impluse Commutation.Class-E Commutation or External Pulse Commutation.

## What is the difference between natural commutation and forced commutation?

Compare Natural Commutation and Forced Commutation. It is also called as phase commutation, line commutation or AC commutation. The natural commutation is only possible in the AC circuit. … There is no power loss in the circuit because no commutation circuit.

## What is commutation voltage?

Commutation is the process when conduction switches from one supply phase to another. … If there is inductance in the supply circuit, a conducting diode will not switch off as soon as one of the other phase voltages exceeds the existing supply phase voltage.

## What is natural or line commutation?

Natural or Line commutation is a Class-F SCR commutation technique in which, a thyristor is turned off due to natural current zero and voltage reversal after every half cycle.

## What is DC to AC converter?

A power inverter, or inverter, is a power electronic device or circuitry that changes direct current (DC) to alternating current (AC). The input voltage, output voltage and frequency, and overall power handling depend on the design of the specific device or circuitry.

## What is commutation in inverter?

Commutation in a circuit is when a current flow changes from one circuit path to another circuit path. As the switches in an inverter bridge turn on and off, the current flow of the connected load supplied by the inverter changes paths from one switch path to the next switch path in the switching sequence.