servo systems servo Servo motor Types of Servo motor Controlling a servo motor Servo drive applications

1. Topics
•servo systems
•servo
•Servo motor
•Types of Servo motor
•Controlling a servo motor
•Servo drive
•applications

2. Your Partner In Productivity
Closed Loop Control
• Controller is the “Brain”
• Drive is the “Muscle”
• Feedback Transducer is the “Eyes”
Motion
Command
Input
Controller
Drive or
Amplifier
Mechanical
Motion
Output
Feedback
Transducer

3. Servo systems are “Closed Loop” in design
control
feedback
control
Width of material
must be very
precisely controlled

4. SERVO

5.  AC servo motor
 Dc servo motor
 Continuous rotation servo motor
 Linear servo motor

6. A.C. servomotors:
Basically it is an induction motor with two windings provided on the
stator.
One of the winding is called reference or main winding which is connected
to constant magnitude ac voltage.
The other winding is called control winding which is connected to voltage
obtained form servo amplifier.
For maximum flux linking air gap kept is minimum.
The ac servomotors are used in the frequency range of 50 Hz to 400 Hz
and from milliwatts power consumption to few hundred watts.

7. D.C. Servomotors
DC servomotor is an ordinary dc motor. But it is a separately excited dc
motor. The dc servomotors are further classified into two types:
1. Armature controlled type and
2. Field controlled type.
In field controlled dc servomotors, the signal from the servo amplifier is
applied to the field winding. The armature is connected to constant current
source.
In armature controlled dc servomotor, the constant current source is
applied to the field winding whereas the servo amplifier output is
connected to the armature.

8. 
Servo drive
PLC (transistor
type)
Servo motor
Power
source
contactor
Load

9.  Position control using Pulse Width Modulation Technique.
 The width of the pulse applied to the motor is varied and send
for a fixed amount of time.
 The pulse width determines the angular position of the servo
motor.
 For example
a pulse width of 1 ms -a angular position of 0 degrees,
a pulse width of 2 ms - a angular width of 180 degrees.

10.  Electronic amplifier used to power electric
servomechanisms.
A servo drive monitors the feedback signal from
the servomechanism and continually adjusts for
deviation from expected behaviour

11.  linear relationship b/n speed and electric control signal
 Steady state stability
 Wide range of speed control
 Low mechanical and electrical inertia
 Fast response

12.  Robotics
 Conveyor belts
 Camera auto focus
 Robotic vehicles
 Solar tracking system
 CNC machines
 Antenna positioning
 Metal cutting & metal forming m/c – millimg m/c, lathe,
grinding, pressing, punching, bending in metal fabrication.
 Textiles
 Printers
 Automatic door openers