II-SEM/ME(C&I) CL7201-Process Dynamics and Control 2014-2015

QUESTION BANK

DEPARTMENT OF ELECTRONICS AND INSTRUMENTATION

SUBJECT CODE: CL7201

SUBJECT NAME: PROCESS DYNAMICS AND CONTROL

SEMESTER:II/ME(C&I)

UNIT I

PART A 1. List any four objectives of process control.

Suppressing the influence of external disturbances, optimizing the performance, increasing the

productivity, Cost effective. 2. Define process Any system comprised of dynamic variables usually involved in manufacturing and production

operations. It is defines as a series of operations during which some materials are placed in more

useful state. 3. What is manipulated variable? It is a variable which is altered by the automatic control equipment so as to change the variable

under and make it conform to the desired value. 4. What do you mean by self regulation?

The output will move from one steady state to another for the sustained change in input. This means that for change in some input variable the output variable will rise until it reaches

a steady state (inflow = outflow). It is the tendency of the process to adopt a specific value of

controlled variable for nominal load with no control operations. 5. Why do we need mathematical modeling of process? The physical equipment of the chemical process we want to control has not been constructed.

Consequently we cannot experiment to determine how the process reacts to various inputs and

therefore we cannot design the appropriate control system. If the process equipment needs to be

available for experimentation the procedure is costly. Therefore we need a simple description of

how the process reacts to various inputs, and this is what the mathematical models can provide to

the control designer. 6. Name a process giving inverse response.

Drum boiler system, in which the flow rate of the cold feed water is increased by a step the total

volume of the boiling water and consequently the liquid level will decreased for a short period

and then it will start increasing.

www.examquestionpaper.in

II-SEM/ME(C&I) CL7201-Process Dynamics and Control 2014-2015

7. Define interacting system and give an example. Load changes in first process affects the second process and vice versa when both are connected

in series nature is called interacting system. E.g. Two level tanks are connected in series.

8. What is meant by non-self regulation? A system that grows without limit for a sustained change in input (constant outflow or outflow

independent of inflow condition). 9. Write any two characteristics of first order process modeling. The smaller the value of time constant the steeper the initial response of the system. A first

order lag process is self regulating the ultimate value of the response equal to K p (steady state

gain of the process) for a unit step change in the input. 10. Distinguish between continuous process and batch process. A process in which the materials or work flows more or less continuously through a plant

apparatus while being treated is termed as continuous process. The problem of continuous

process is due to load changes. (e.g.) storage vessel control. A process in which the materials or

work are stationary at one physical location while being treated is termed as batch process. (e.g.)

furnace. 11. Explain the function of controller. The element in a process control loop that evaluated error of the controlled variable and initiates

corrective action by a signal to the controlling variable. 12. What is the purpose of final control element? Components of a control system (such as valve) are used to directly regulate the flow of energy

or materials to the process. It directly determines the value of manipulated variable. 13. Define Process control. It is the scheme that describes how much the manipulated variable should change in order to

bring the controlled variable back to the set point. 14. List the two types of process control. Direct process control – Controlled variable directly indicates the

Performance of the process Eg. Water heater system In Direct Process control – Controlled

variable indirectly indicates the performance of the process. Eg. Annealing 15. What is Servo operation and Regulatory operation? If the purpose of the control system is to make the process follow the changes in set point as

quick as possible, then it is servo operation.

www.examquestionpaper.in

II-SEM/ME(C&I) CL7201-Process Dynamics and Control 2014-2015

In many of the process control applications, the purpose of control system is to keep the output

(controlled variable) almost constant in spite of changes in load. Mostly in continuous processes the set point remains constant for longer time. Such a operation

is called regulatory operation. 16. What is mathematical modeling? Set of equations that characterize the process is termed as Mathematical Modeling. Proportional band. K p =100/PB 17. Define offset. It is the steady state deviation (error) resulting from a change in value of load variable. 18. Define integral (reset) windup? The overcharging in the presence of a continuous error of the integral capacitor which must

discharge through a long time constant discharge path and which prevents a quick return to the

desired control point.

19. What is the significance of Piping and Instrumentation Diagram (P&ID) in control loops?

The instrument technician is interested in the interconnections of individual instruments,

including all the wire numbers, terminal numbers, cable types, instrument calibration ranges, etc.

The proper form of diagram for this level of final detail is called a loop diagram 20. Define lumped parameters and distributed parameters models. Distributed parameters models: Models that take spatial variations into account.

Lumped parameters models: The spatial coordinate is divided into small sections; within each

section the system properties are assumed to be homogeneous.

www.examquestionpaper.in

II-SEM/ME(C&I) CL7201-Process Dynamics and Control 2014-2015

PART-B 1. Obtain the mathematical modeling of an Interacting system.

2. Obtain the mathematical modeling of a Non-Interacting system.

3. Explain detail about continuous process and batch process.

4. Obtain the mathematical model for a typical thermal process.

5. Define self regulation. Give an example of a self regulated process 6. What is a first order system and how do you derive the transfer functions of a first order lag or

of a purely capacitive process?

7. With examples explain servo and regulatory operation.

8. Determine the transfer function H(s)/Q i(s) for the liquid level system [Resistances R1, R2 and R3

are linear. The flow rate from tank-4 is maintained constant at ‘a’ by means of a pump.]

9. Explain about bump less transfer. 10. Explain in detail about practical forms of PID controller

UNIT – II PART A

1. Write Ziegler- Nicolas turning formulae.

For proportional controller: Kp = 0.5 Ku.

For Proportional – integral controller: Kp = 0.45 Ku, Ti = Pu/1.2.

For Proportional – integral – derivative controller: Kp = 0.6 K u , T i = P u /2, T d = P u /8. 2. Define controller turning. Deciding what values to be used for the adjusted parameters of the controller is called controller

turning. 3. What is process reaction curve? In process controller, the reaction curve is obtained by applying a step change (either in load or

in set point) and plotting the response of the controlled variable with respect to time. 4. What performance criterion should be used for the selection and turning of controller? Keep

the maximum error as small as possible. Achieve short settling time.

Minimize the integral of the errors until the process has settled set Point. 5. Define ultimate gain. The maximum gain of the proportional controller at which the sustained oscillations occur is

called ultimate gain (Ku).

www.examquestionpaper.in

II-SEM/ME(C&I) CL7201-Process Dynamics and Control 2014-2015

6. What is ITAE and when to go for it?

ITAE mean Integral Time Absolute Error. To suppress the errors that persist for long time,the

ITAE criterion will tune the controllers better because the presence of large t amplifies the

Effect of even small errors in the value if integral. 7. What are the parameters required to design a best controller? Process Parameters, Controller parameters (Kp,Ti, Td),performance creation (ISE, IAE, IATE) 8. Write any tow practical significance of the gain margin. It constitutes a measure of how far the system is the brink of instability. Higher the gain margin (above the value of one), the higher the safety factor we use controller turning. Typically, a control designer synthesizes a feedback system with gain margin larger than 180° . 9. Why is it necessary to choose controller settings that satisfy both gain margin and phase

margin?

The gain margin and Phase margin are the safety factors which are used for the design of a

feedback system. Beyond the phase margin and gain margin the system goes to unstable position. 10. What is turning a controller based on quarter – decay ratio?

It is the procedure in which adjusting the proportional gain of controller up to ¼th

decay ratio

waveform is obtained. 11. Name the time integral performance criteria measures. Integral Square Error (ISE), Integral of absolute value of error (IAE),Integral of time weighted

absolute error. 12. Define Integral Square Errors (ISE) If we want to suppress large errors, ISE is better than IAE because errors are squared and

contribute more to the value of integral. 13. Define Integral Absolute Errors (IAE) If we want to suppers small errors, IAE is better than ISE because when we square small

numbers, they even become smaller. 14. Define Integral of Time weighted Absolute Error (ITAE) To suppress errors that persist for long times, ITAE criterion will tune the controllers better

because the presence of large t amplifies the effect of even small errors in value of integral. 15. Define One-quarter decay ratio. It is reasonable tradeoff between fast rise time and reasonable setting time. 16. Give the satisfactory control for gas liquid level process.

Proportional Control is the satisfactory control for liquid level process. 17. Give the satisfactory control for gas pressure process. Proportional

Control is the satisfactory control for liquid level process.

www.examquestionpaper.in

II-SEM/ME(C&I) CL7201-Process Dynamics and Control 2014-2015

18. Give the satisfactory control for vapor pressure process. PI Control is the satisfactory control for vapor pressure process having fast response. 19. Give the satisfactory control for composition process& temperature process. PID Control is the satisfactory control for composition process& temperature process. 20. Define Cohen-Coon method. The basic approach is to open the process-control loop so that no control action (f/b) occurs. This

is usually done by disconnecting the controller output from the final control element. All of the

process parameters at their nominal values. this method can be used for systems with self

regulation. This also called as open loop transient response method

PART-B 1. Explain controller tuning using one-quarter decay ratio.

2. Explain the basis of selection of type of controller for various processes.

3. Explain controller tuning using process reaction curve method.

4. Explain controller tuning using Zeigler Nicholas method.

5. How is ITAE criterion different from IAE and ISE?

6. Describe the characteristics of two discontinuous controllers.

7. Describe the characteristics of any three continuous controllers

8. Describe the characteristics of composite control modes

9. Given the error values plot a graph of a P+I controller output as a function of time Kp = 5,

KI = 1 s-1

and PI(0)=20% 1

Error

0 1 2 3 4

10. Given the error values plot a graph of a PD controller output as a function of time Kp=5, KD=0.5s and PI (0) =20%

Error 1

0 1 2 3 4 5

www.examquestionpaper.in

II-SEM/ME(C&I) CL7201-Process Dynamics and Control 2014-2015

UNIT-III PART A

1. Define ratio control.

Ratio control is a special type of feed forward control where two disturbances are measured and

held in a ratio to each other. 2. Define cascade control. Cascade control is defined as a control system composed of two loops where the set point of one

loop (the inner loop) is the output of the controller of the other loop (the outer loop) 3. When cascade control will give improved performance than conventional feedback control? In

some process the secondary variables in it introduce disturbance throughout the system is

measured and controlled by a separate loop. 4. Explain the purpose of cascade control for heat exchangers? In heat exchangers, the control objective is to keep the exit temperature of stream. But the flow

rate of the stream creates the low disturbance throughout of it’s a function. The secondary loop is

used to compensate the flow rate of the stream. 5. What is meant by auctioneering control? Such control configurations select among several measurements the one with the highest value

and feed it to the controller. Thus it is a selective controller which possesses several measured

outputs and only one manipulated input. 6. What is split-range control? To control A single process output can be controlled by co-coordinating the actions of several

manipulated variables all of which have same effect on controlled output. Such systems are

called split-range control systems. 7. Differentiate split-range control and selective control. Split-range control system involves one measurement and more than one manipulated variables

but selective control system involves one manipulated variables and several controlled outputs. 8. Why are fuel and air sent at a specified ratio into a combustion chamber?

To obtain the most efficient combustion. 9. What are decouplers? The special element introduced in a system with two strongly interacting loops to cancel the

interaction effect between the two loops and thus render two non-interacting control loops is

called decoupler.

10. When is inferential control used?

It is used in some cases where the output of the process and the influence of the disturbance

cannot be measured. 11. What are the advantages of feed forward controller? Acts before the disturbance is felt by the process. It is good for slow systems.

www.examquestionpaper.in

II-SEM/ME(C&I) CL7201-Process Dynamics and Control 2014-2015

12. What are the disadvantages of feed forward controller? *Requires identification of all possible disturbances and their direct

impact. *Cannot cope with unmeasured disturbances.

*It is unsatisfactory for slow processes with significant dead time 13. What are the advantages of feedback controller? It does not require identification and measurement of disturbance.

14. What are the advantages of feed forward -feedback controller? *W e can add feed forward with existing feed back to obtain satisfactory

performance. *All load variables need not be measured.

*No need for complete mathematical model. 15. Define override control. During the normal operation of a plant (or) during its start up(or) shut down it is possible that

dangerous situations may arise which may load to destruction of equipment and operating

personnel. 16. When is ratio control used? The ratio between two (or) three input variables is controlled at a specific value to achieve some

objective.Two types of flow

(i)Wild flow

(ii) Controlled flow. 17. Define feed forward control. *Feedback control never gives ideal performance in that case used for feed forward control.

*It required mathematical model. *It computes the value of manipulated variable to keep the cv to set point for the current values

of load variable u1, u2, u3, u4. 18. What is mean by dead time compensation? Smith proposed a modification of the classical feedback control system for the computation of

dead time effects.

It is known as smith predictor (or) dead time compensator. 19. Define IMC controller. IMC scheme makes use of a proposed model to infer the effects of un measurable disturbance on

the process output and then counteracts that effect. 20. When is feed forward control is used

*Feedback control never gives ideal performance * Controller starts reaching only after the error occurs.

This kind of situations feed forward control is used

www.examquestionpaper.in

II-SEM/ME(C&I) CL7201-Process Dynamics and Control 2014-2015

PART-B 1. What are the main advantages and disadvantages of cascade control? For what kind of

processes can you employ cascade control? 2. Explain cascade control of typical processes.

3. Explain split range control of typical processes.

4. Explain feed forward control of typical processes.

5. Explain ratio control of typical process.

6. Compare the advantages and drawbacks of Feed forward and feedback controllers.

7. Derive the estimator expression of inferential control which relates the unmeasured

controlled outputs to measured quantities

8. Explain in detail about override control. 9. Explain in detail about smith predictor control scheme.

10. How to synthesis the controller using IMC.

UNIT-IV PART A

1. What are decouplers?

When the designer is confronted with two strongly interacting loops, then introduces in the

control system special new elements called decouplers.

2. Define multi loop control Each manipulated variable depends on only a single controlled variable, i.e., a set

of conventional feedback controllers.

3. Define MIMO system. In MIMO, one or more manipulated variables can affect the interactions of controlled variables

in a specific loop or all other control loops. A MIMO control scheme is important in systems

that have multiple dependencies and multiple interactions between different variables- for

example, in a distillation column, where a manipulated variable such as the reflux ratio could

directly or indirectly affect the feed flow rate, the product composition, and the reboiler energy.

Thus, understanding the dependence of different manipulated and controlled variables in a

MIMO control scheme could be extremely helpful in designing and implementing a control

scheme for a process.

4. What is mean by multi variable control? Each manipulated variable can depend on two or more of the controlled variables

Examples: decoupling control, model predictive control. www.examquestionpaper.in

II-SEM/ME(C&I) CL7201-Process Dynamics and Control 2014-2015

5. What are the characters available for designing of MIMO system?

*Control system is composed of several interacting control loops.

*RGA method which determines how the controlled &manipulated variables should be

completed to yield control loops with minimal interaction.

*The design of special control systems with non-interacting loops.

6. Define SISO system. Single variable Input or Single variable Output (SISO) control schemes are just one type

of control scheme that engineers in industry use to control their process.

*That can be used for single manipulated variable& single controlled output.

7. Define multi variable system Multivariable process has many variables exists in the process & must be regulated.

Multivariable system can have such a complex interaction pattern that the adjustment of a

single set point causes a profound influence on many other control loops in the process.

8. How to select the loops with the help of RGA. The relative gain array provides exactly such a methodology, whereby we select pairs of input

and output variables in order to minimize the amount if interaction among the resulting loops.

9. Define RGA. Relative Gain Array is an analytical tool used to determine the optimal input-output variable

pairings for a multi-input-multi-output (MIMO) system. In other words, the RGA is a

normalized form of the gain matrix that describes the impact of each control variable on the

output, relative to each control variable's impact on other variables. The process interaction of

open-loop and closed-loop control systems is measured for all possible input-output variable

pairings. A ratio of this open-loop 'gain' to this closed-loop 'gain' is determined and the

results are displayed in a matrix.

10. How to design non-interacting loops. The purpose of decouples is to cancel the interaction effects between the two

loops&thus render two non-interacting loops.

Consider, initially both the outputs are at desired set point values.

i.e. change in y2 causes change in y1.

11. How to determine RGA. The relative gain array is a square matrix, which implies that the number of

manipulated Variables are equal to the number of controlled outputs.

There are two main ways to calculate RGA:

(1) Experimentally determine the effect of input variables on the output variables,

then Compile the results into an RGA matrix.

(2) Use a steady-state gain matrix to calculate the RGA matrix.

www.examquestionpaper.in

II-SEM/ME(C&I) CL7201-Process Dynamics and Control 2014-2015

12. How to design a decouplers. I f the decouplers are designed using steady-state models for the process, it is called steady-

state (or) static decoupling When the designer is confronted with two strongly interacting

loops, then introduces in the control system special new elements called decouplers.

13. Define decoupling control. (i)The interaction among the control loops of a MIMO process.

(ii)The RGA method, which determines how the controlled and manipulated variables should

be controlled to yield control loops with minimal interaction.

(iii) The design of special control systems with non-interacting loops.

14. Define dynamic matrix control. Dynamic Matrix Control (DMC) is one of the most popular methods of model predictive

control. It is especially powerful for multiple input multiple output (MIMO) control systems.

A way to have students explore the nature of DMC control is to use it on a simulated process.

15. Draw the block diagram of 2-input&2-output closed loop system.

www.examquestionpaper.in

II-SEM/ME(C&I) CL7201-Process Dynamics and Control 2014-2015

16. Draw the block diagram of 2-input&2-output open loop system. 17. What is mean by pairing? The goal of the RGA and NI analysis is to quantitatively determine the optimal variable pairing

for a given process. Some basic rules to remember when attempting to obtain an optimal pairing

of control loops in a system are:

• Rule 1: The positive RGA elements that are closest to 1.0 should have the corresponding

manipulated and controlled variables paired. When the CN number is large, implying a

less decoupled system, one should look for the max RGA elements.

• Rule 2: If the NI value is negative, the loop pairing for that control system configuration

is unacceptable.

18. What are the reasons occurs in designing a IMC controller. Model uncertainty is explicitly taken into account in an internal model strategy.

Internal model control strategy is constructed by incorporating a model for the actual plant. 19. When is IMC control is

used. (i)Used for servo operation

(ii)’u’ affects ’c’ immediately 20. List the merits of internal model controller. *At steady state, the controller will give offset free response (perfect control at steady state).

*The controller can be used to shape both the input tracking and disturbance rejection

responses. *Provides time delay compensation

PART-B 1. How to find out poles &zeros of MIMO system. 2. Explain in detail about properties and application of RGA. 3. Explain in detail about multivariable system. 4. Explain in detail about RGA and selection of loops. 5. Explain in detail about interaction and decoupling of control loops. www.examquestionpaper.in

II-SEM/ME(C&I) CL7201-Process Dynamics and Control 2014-2015

6. How to select the paring of inputs and outputs using RGA. 7. Explain the steps to minimize coupling in multivariable control. 8. Explain the steps to minimize decoupling in multivariable system. 9. Consider a process with the following input-output relationships.

Select the loops using RGA method.

10. Find out paring of input and output for a given transfer function using RGA analysis.

UNIT-V PART A

1. Define PH.

pH is a measure of the hydrogen ion concentration of a solution. Solutions with a high

concentration of hydrogen ions have a low pH and solutions with low concentrations of H+ ions

have a high pH. This may seem like a confusion way to express these relationships, and it is,

until you understand what pH stands for. The equation that defines pH is given as follows:

pH=-log[H+] concentration, which is read: the pH is equal to minus the log of the H+

concentration. 2. What are methods available for PH measurement?

Hydrogen gas platinum electrode was originally used for measuring [H+] but is not useful for

clinical pH analysis. The sample had to be fully saturated with hydrogen gas and all the oxygen eliminated. The method is not suitable for rapid automated analysis of blood samples. Current methods of pH measurement include: • Colorimetric methods. Litmus paper is used to decide between acid or base but papers

incorporating pH-sensitive dyes have been designed to measure finer gradations of pH (eg urine

pH is estimated by use of indicator dyes in dipsticks). Progress in colorimetric pH methods using

indicator dyes (incl. fluorescent dyes) has lead to the development of accurate intravascular

methods of pH measurement. The Paratrend 7+ is a commercially available system for

measuring intra-arterial pH and blood gases. • Glass electrodes. These are widely used in medical applications eg blood-gas machines.

• ISFET electrodes - using 'Ion-selective field effect transistors'. These are used mostly

in industry but have been developed for intravascular use. 3. What are the design procedures followed by MVC. 1. What are the control objectives?

2. What outputs should be

measured? (a)primary measurement

(b) Secondary measurement

3. What inputs can be measured?

4. What manipulated can be used?

5. What is the configuration of the control loops?

www.examquestionpaper.in

II-SEM/ME(C&I) CL7201-Process Dynamics and Control 2014-2015

4. What is the configuration of the control loop used for MVC? Once all the possible measurements and manipulations have been identified, we need to decide

how they are going to be interconnected through the control loops 5. How PH control systems work for two-position control? The two positions or on-off control system is designed so that the element controlling reagent

additions is always set in one of two positions, either fully open (on) or fully closed (off) .

Such systems are generally limited to continuous processes where waste flow rate is relatively

small and residence (or hold- up) time with in the control system is relatively large. Residence

time is the average time a unit of volume is "held up" within the reaction vessel

6. Define CSTR.

*Continuously Stirred Tank Reactor (CSTR).

*Reactors are fed in to the tank continuously stirred to remove the amount of heat.

*The reaction is exothermic in the heat generated by this reaction is removed by the coolant.

7. Define binary distillation column.

General countercurrent- flow, multistage, binary distillation Column shown below consists of A

column of N theoretical stages A total condenser to produce a reflux liquid to act as an

absorbent and a liquid distillate A partial reboiler to produce boil up vapor to act as a stripping

agent and a bottoms product An intermediate feed stage. This configuration allows one to

achieve a sharp separation, except in cases where an zoetrope exists where one of the products

will approach the a zoetrope Concentration. 8. What is mean by predictive control? Model predictive control (MPC) is an advanced method of process control that has been in use in the process industries in chemical plants and oil refineries since the 1980s. In recent years it

has also been used in power system balancing models. [1]

Model predictive controllers rely on

dynamic models of the process, most often linear empirical models obtained by system identification. The main advantage of MPC is the fact that it allows the current timeslot to be optimized, while keeping future timeslots in account. This is achieved by optimizing a finite time-horizon, but only implementing the current timeslot. MPC has the ability to anticipate future events and can take control actions accordingly. PID and LQR controllers do not have this predictive ability. MPC is nearly universally implemented as a digital control, although there is research into achieving faster response times with specially designed analog circuit. 9. How to design a non interacting control loops. The purpose of decouplers is to cancel the interaction effects between the two loops and thus

render two non interacting control loops. 10. Mention any two properties of RGA.

There are two main ways to calculate RGA:

(1) Experimentally determine the effect of input variables on the output variables, and then

compile the results into an RGA matrix.

(2) Use a steady-state gain matrix to calculate the RGA matrix. 11. What is the need for pairing inputs and outputs in a multi-loop control? *Interaction among the control loops of a MIMO process.

www.examquestionpaper.in

II-SEM/ME(C&I) CL7201-Process Dynamics and Control 2014-2015

*The relative gain method, which determine how the controlled and manipulated variables

should be coupled to yield the control loops with minimal interaction. *The design of special control systems with non- interacting loops. 12. Name the control schemes for a CSTR process. 1. Cascade control

2. Feed-forward control

3. Feedback control 13. List the parameters to be measured and controlled in a distillation

column. Controlled variables:

1. Overhead composition

2. Bottoms composition

3. Accumulator level

4. Bottoms level 5. Column pressure

Manipulated variables: 1. Reflux flow rate

2. Re boiler heating medium flow rate

3. Distillate flow rate

4. Bottoms flow rate

5. Condenser flow rate 14. What manipulated variables should be used for MVC? *A MIMO system processes several manipulated variables which can be used for the design of a

control system. *The selection of the most appropriate manipulations is a very critical problem& should be

approached 15. What are problems occurs in design of MVC. (i)It is important to select the proper variable pairing for interactive feedback Control. (ii)

Using interaction compensation will frequently help to provide stability effect on Interactive feedback loops and allows higher tuning.

(iii)The use of the selective (or) override control where possible will minimize the

need for interacting feedback loop. 16. What are the control objectives MIMO control systems? How many and which of all possible should be controlled at desired values the answer identifies

the objective of the control.

17. What outputs should be measured for system MIMO control.

(a)primary measurement:These are the controlled outputs through which we can determine

directly if the control objectives are satisfied.

(b) Secondary measurement:These are not used to monitor directly the control objectives but are

auxiliary measurements employed for cascade, adaptive. www.examquestionpaper.in

II-SEM/ME(C&I) CL7201-Process Dynamics and Control 2014-2015

18. Give the structure of a generalized predictive controller. 19. Define predictive controller. 1. Future values of output variables are predicted using a dynamic model of the process and

current measurements. Unlike time delay compensation methods, the predictions are made for

more than one time delay ahead.

2. The control calculations are based on both future predictions and current measurements.

3. The manipulated variables, u(k), at the k-th sampling instant are calculated so that they

minimize an objective function, J.

Example: Minimize the sum of the squares of the deviations between predicted future outputs

and specific reference trajectory.

4. Inequality & equality constraints, and measured disturbances

are included in the control calculations.

5. The calculated manipulated variables are implemented as set point for lower level control

loops. (cf. cascade control). 20. Name the control schemes for binary distillation column. 1. Cascade control

2. Feed-forward control

3. Feedback control

4. International control.

5. Ratio control

6. Feedback- Feed-forward control

7. Split range control

www.examquestionpaper.in

II-SEM/ME(C&I) CL7201-Process Dynamics and Control 2014-2015

PART-B

1. Explain in detail the binary distillation column. 2. Explain in detail about transfer matrix representation of multivariable system 3. Explain in detail about multi loop control. 4. Explain in detail about multi variable PID control. 5. Discuss various control schemes used for the control for binary distillation column. 6. Explain in detail about design of non interacting control loops. 7. Explain in detail the various control schemes used for PH measurement. 8. Explain in detail the various control schemes used for four tank system 9. Explain in detail about generalized predictive control. 10. Explain about various control schemes used for CSTR

www.examquestionpaper.in