Introduction to Database Modeling

Data Base Dynamic Modeling Summer Semester 2011
Assignment

Process System Engineering (PSE)
Solution

Identify Continuous and ARX models

Name:

Hossein

Sure Name: ShirGir Matr.Nr.
1

146074
Hossein ShirGir, 146074 , Dortmund ,Germany

a) Identify continuous models that match the observed output. Please proceed with the following steps: 1- Consider that the continuous models should be built as products of the following four transfer functions:

For starting I ran the program by initial point and G1 which defined by assignment and I got the figure G1. Its starting point for getting the map, the first transfer function is second order but there is deviation in some points so we should improve the transfer function.

2

Hossein ShirGir, 146074 , Dortmund ,Germany

FIG.1 G1

Comment: Transfer function is second order transfer function there is deviation should be improve and eliminate with effect of other transfer function.

3

Hossein ShirGir, 146074 , Dortmund ,Germany

FIG.2 G1.G2

Comment: This transfer function is resulted by multiplication of G1 and G2 some deviation of first map eliminated by effect of denominator of second transfer function the higher order of denominator seems to improve function convergence.

4

Hossein ShirGir, 146074 , Dortmund ,Germany

FIG.3 G1.G4

Comment : This map resulted by G1 and G3 multiplication it seems better than G1 alone because the denominator order improved in resulted transfer function but because of lack of nominator order it doesn’t has stability as G1.G2 so the deviation increase in compare of previous map and transfer function.

5

Hossein ShirGir, 146074 , Dortmund ,Germany

FIG.3 G1.G4

Comment: as you see there is a great deviation between true value and PT. So it is easy to recognize that selected transfer function is not suitable as enough as to met the process control demand. It shows even we have denominator but in this case it makes first transfer