Stepper motors

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ALİ RIZA GÜMÜŞ 14371962058
EVREN KÖYBAŞI 28853171050
VOJTECH HEMALA 90000004215
Eskişehir, 2013
PID Controller
 So, what is a Controller?
 Structure of a Controller
 Modes of Controllers (P, PI, PD, PID)
PI Controller
 PI controller will eliminate forced oscillations and steady state error
resulting in operation of on-off controller and P controller respectively.
 However, introducing integral mode has a negative effect on speed of the
response and overall stability of the system. Thus, PI controller will not
increase the speed of response.
 This problem can be solved by introducing derivative mode which has
ability to predict what will happen with the error in near future and thus
to decrease a reaction time of the controller.
DISCRETIZING A PID CONTROLLER
Development of discrete-time PID
controller
Transforming method
A stepper motor is a brushless DC
electric motor that divides a full rotation
into a number of equal steps
Motors definitions
 Step motors are seperated two
main part unipolar and bipolar
steppers motor.
Unipolar & Bİpolar
 A unipolar stepper motor has one winding with center
tap(common wire) per phase
 In bipolar motors have a single winding per phase
Operation of stepper motors
 To operate step motors , you must apply pulse to each
coil in different phase.
 Driving this type of motor is a bit different from the
others
Stepper motor positioning
 All dc servo motors we can take position info by
connecting the potentiometer to its shaft
 In step motor rotates step by step , because of this we
can divide the pot partially to determine the each step
.It means each step has a voltage value.
Analog & Digital Operations
 In PLC s7 200 cpu 224 xp all operations can be made.
 First of all we are looking some useful code for this
PLC. Then we will see the example of its application
Useful Codes
 BCDI OUT : Convert BCD to Integer
 IBCD OUT: Convert Integer to BCD
 BTI IN, OUT Convert Byte to Integer
 ITB IN, OUT Convert Integer to Byte
 ITD IN, OUT Convert Integer to Double Integer
 DTI IN, OUT Convert Double Integer to Integer
 DTR IN, OUT Convert DWord to Real
Online Subtract Operation
 In this example lots of operatıons are used.
 The main idea is :
To observe the analog output voltage of PLC when we
apply desired input voltage
We can follow these steps to solce
Example
 e.g. : Choose a reference voltage as 2,4 V .Then apply a



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arbitrary voltage.When you measure the analog output of
PLC , you will see the voltage “applied voltage – reference
(2,4 V)”. When you change the input , the output will
change as proportional.
SM
0.0
MOVR
2.4 , VD0
// VD0=2,4 V
REFERENCE
ITD
AIW0,VD4
DTR
VD4,VD4
//INPUT 32 BIT
REAL NUMBER
Last page
 /R
 MOVR
 -R
 *R
 TRUNC
 DTI
OUTPUT
3276,8,VD4
VD0,AC0
VD0,AC0
3276,8 , AC0
AC0,VD8
VD8,AQW0
//AC0=2,4
//AC0=AC0-VD0
// ANALOG
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