FACTORS INFLUENCING THE CHOICE OF ELECTRICAL DRIVE


                     Electrical motors of various designs are available to meet the needs of various classes of industry. So the selection of motor itself has become an important and tedious process. The various factors that are to be considered in the selection of an electric motor for a particular service are:

1. Steady state operation:

Nature of speed torque characteristics

Ø  Range of speed

Ø  Duty cycle and duty ratio

Ø  Speed fluctuations

Ø  Speed regulations

2. Transient operation:

                        Transient is nothing but switched from one condition to another by change in applied voltage or by change in one of the circuit elements during a period of time, branch currents and voltages change from their former values to new one with very short duration is called transient.

This may change the performance of drives so during the selection period transient is important one.

Ø  Values of acceleration and deceleration

Ø  Starting

Ø  Braking

Ø  Reversing

3. Related with source:

                        With electric drive should select the source depends on the following for a particular application.

Ø  Magnitude of voltage

Ø  Voltage fluctuation power factor

Ø  Harmonics and their effects as their load.

4. Need of cost:

                       The economy is the main factor for all process while selecting the electric drives for specific application.

Ø  Capital cost

Ø  Running cost

Ø  Maintenance cost

Ø  Should be in considerable value.

5. Life period of the drive:

Ø  Life time of the electric drive should maximum as possible.

6. Location and Environment:

                        For example drives may be adopted like coal mines, sewing mills, Rolling mills and etc, all should selects based on their needs.

7. Flexibility:

 The electric drive should be flexible for

Ø  Speed control

Ø  Braking

Ø  Reversing and etc.

8. Reliability:

Ø  The electric drive should be reliable.

9. Space and Weight restrictions:

                        Electric drive should be compact in size and occupy less space based on the application and needs.

10. Appearance:

                       The electric drive should be neet and clean.

 

 

 

 


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