Page 201 - Electrician - TT (Volume 2)

ELECTRICIAN - CITS

• They have flexible manage characteristics due to the utilization of electric braking.
• At present, the AC motors motor is used within variable speed drives because of semiconductor converters
development.
Disadvantages
The disadvantages of electrical drives include the following.
• This drive cannot be used where the power supply is not accessible.

• The power breakdown totally stops the entire system.
• The primary price of the system is expensive.
• The dynamic response of this drive is poor.
• The drive output power which is obtained is low.

• By using this drive noise pollution can occur.
Applications of Electrical Drives: The applications of electrical drives include the following.
• The main application of this drive is electric traction which means transportation of materials from one location
to another location. The different types of electric tractions mainly include electric trains, buses, trolleys, trams,
and solar-powered vehicles inbuilt with battery.
• Electrical drives are extensively used in the huge number of domestic as well as industrial applications which
includes motors, transportation systems, factories, textile mills, pumps, fans, robots, etc.
• These are used as main movers for petrol or diesel engines, turbines like gas otherwise steam, motors like
hydraulic & electric.

Thus, this is all about the fundamentals of electrical drives. From the above information, finally, we can conclude
that a drive is one kind of electrical device used to control the energy which is sent to the electrical motor. The
drive supplies energy to the motor in unstable amounts & at unstable frequencies, thus ultimately controls the
speed and torque of the motor. Here is a question for you, what are the main parts of the electric drive.

Individual electric drive
In this drive each individual machine is driven by a separate motor. This motor also imparts motion to various
parts of the machine.

Multi motor electric drive : In this drive system, there are several drives, each of which serves to actuate one
of the working parts of the drive mechanisms.
e.g: Complicated metal cutting machine tools

Paper making industries.
Rolling machines etc.
A modern variable speed electrical drive system has the following components
- Electrical machines and loads
- Power modulator

- Sources
- Control unit
- Sensing unit

Electrical machine
Most commonly used electrical machines for speed control applications are the following.
DC machines
Shunt, series, compound, DC motors and switched reluctance machines.

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CITS : Power - Electrician & Wireman - Lesson 93-100