Dynamic Behavior

Question 1

The ratio of the final change in PV output to the final change in input

Answer 1

K (steady-state gain)

Question 2

It defines the speed of the response. For 1st order processes, after τ seconds, the PV output is 63.2% of the way to its final value.

Answer 2

τ (time constant)

Question 3

In a ramp response, the exponential term, influences the response mostly at the _____ only

Answer 3

onset

Question 4

Time it takes to reach the new steady-state for the first time

Answer 4

Rise time

Question 5

Computed as a/b

Answer 5

Overshoot

Question 6

Time it takes to reach the first maximum value

Answer 6

Time to first peak

Question 7

Time between two successive peaks in the response

Answer 7

Period

Question 8

Computed as c/a

Answer 8

Decay ratio

Question 9

s-values where T.F. is infinity

Answer 9

Poles

Question 10

s-values where T.F is zero

Answer 10

Zeros

Question 11

A plot of the complex s-plane showing the location of poles and zeros. The abscissa is the real part of s, and the ordinate is the imaginary part of s

Answer 11

Pole-zero plot

Question 12

Processes whose transfer functions have m=n.

Answer 12

Lead-lag process

Question 13

In lead-lag process, the initial value of their step response can be non-zero, hence, they can have a _____

Answer 13

jump discontinuity

Question 14

If the pole-zero of a process T.F contains a pair of poles equidistant from the x-axis, they are complex conjugate pairs.

Answer 14

Oscillatory behavior

Question 15

A right half-plane zero produces an initial output response that goes opposite to the direction of the input.

Answer 15

Inverse response

Question 16

The presence of poles at the origin indicate an integrating process. This means that the output response is bounded for open inputs.

Answer 16

Integrators

Question 17

The area under the input is continuously increasing with time

Answer 17

Open input

Question 18

The area under the input is finite with time

Answer 18

Closed input

Question 19

Uses the concept of BIBO (bounded input, bounded output).

Answer 19

Stability

Question 20

If the process T.F has right half-plane poles, an _____ response will arise regardless of input.

Answer 20

Unstable

Question 21

The signal values does not go beyond a certain region all the time

Answer 21

Bounded input

Question 22

The signal eventually decreases or increases unceasingly with time.

Answer 22

Unbounded inputs

Question 23

Means that whether we apply an input to the system now or θ seconds from now, the output will be identical except for a time delay of θ seconds

Answer 23

Time-invariance

Question 24

Rule use in approximating higher-order T.F using time delay

Answer 24

Skogestad’s half-rule