Parameters of the PT2 element Classification of the PT 2 element The PT2 element (time delay element of the 2nd order) is expressed by the differential equation
The parameter T stands for the time constant of of the element, D is its damping and and again KP is the proportional coefficient. The system demonstrates arious !inds of behaior depending on the magnitude of its damping D" D # $" The PT2 element can be understood in this case as a series connection of t%o PT$&elements. The system's step response is aperiodic. D $" $" n thi this s cas case e the the PT2 element is capable of oscillation. The step response of the system is thus oscillatory. *t *t the extreme D + the oscillation is undamped. The follo%ing -igure sho%s the step response and the bloc! s ymbol of the PT 2 element for the t%o cases.
The PT2 element li!e the PT$ element is a transfer element with compensation and time delay (see the follo%ing graphic).
Example for a PT2 element PT2 elements contain exactly t%o energy storage elements. The -igure belo% illustrates a mechanical PT2 element consisting of a spring, a mass and shoc!& absorber.
-ig. right" pring&mass&shoc! absorber system as an example of a PT2 element.
/hich t%o components constitute the energy storage elements0 s the system able to oscillate0 1o% is the damping determined0 nter your ans%er into the follo%ing ans%er box.
Experiment n the follo%ing experiment the step responses of the t%o series connected PT$ elements on the experiment card 3controlled system simulation3 (452$&67) are determined. -irst set up the follo%ing experiment circuit.
*ctiate the step response plotter and configure it as sho%n in the Table.
Settings Input 8hannel *
9eas. range" $ :
8oupling" D8
8hannel ;
9eas. range" $ :
8oupling" D8
4ffset"
4ther
Settings Output tep response from ... to ...
6=
Delay time>ms
9easurements
? Settings Diagram
Display
8hannel *
x&axis from ... to ...
.? s
y&axis from ... to ...
$
@o% determine the step response and copy the plot into the space resered for it belo%.
$
=
x$" y $"
x2" .25
C
y 2" 5.C dx"
B
.25 dy " 5.C
A
dy>dx" 2
6
5
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2
$
t>s
Langkah respon dari elemen PT2 Nilai kemiringan respon langkah pada satu waktu t = 0. Nilai Koefisien KP proporsional dari elemen PT Kp + 5D.C= t+ ,.25D
$
=
x$" y $"
x2" .25
C
y 2" 5.C dx"
B
.25 dy " 5.C
A
dy>dx" 2
6
5
?
2
$
t> s
Langkah respon dari elemen PT2 Nilai kemiringan respon langkah pada satu waktu t = 0. Nilai Koefisien KP proporsional dari elemen PT Kp + 5D.C= t+ ,.25D
$
=
x$" y $"
x2" .25
C
y 2" 5.C dx"
B
.25 dy " 5.C
A
dy>dx" 2
6
5
?
2
$
t> s
$
=
x$" y $"
x2" .25
C
y 2" 5.C dx"
B
.25 dy " 5.C
A
dy>dx" 2
6
5
?
2
$
t> s
$
=
x$" y $"
x2" .25
C
y 2" 5.C dx"
B
.25 dy " 5.C
A
dy>dx" 2
6
5
?
2
$
t> s
$
=
x$" y $"
x2" .25
C
y 2" 5.C dx"
B
.25 dy " 5.C
A
dy>dx" 2
6
5
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2
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t> s
x$" y $" x2" .2 y 2" 5. dx" .2 dy " 5. dy > 2
x$" y $" x2" .2 y 2" 5. dx" .2 dy " 5. dy > 2
