The ideal on-off control switches between two possible states depending on the sign of the error. 

i) What is the serious drawback of the ideal on-off control in the presence of a control valve? 

ii) Which modification of the on-off control reduces the above drawbacks?

  1. Write the transfer function of your SOPTD model. 

2. Comment on how appropriate would a FOPTD model be for these data?

For the given discrete-time model express the steady-state gain in terms of the five parameters. y(k)= ay(k-1) + ay(k 2) + azy (k 3) + bu(k-1) + bu(k 2)