Process Process control Types of control Positive Feedback Negative Feedback

1. Introduction of
process control

2. Process
• It is defined as:-
• Physical or chemical change of matter.
• Energy conversion
• E.g, change in pressure, temperature, speed, electrical, potential, etc.
• A process in a collection of vessels, pipes, fitting, gauges etc. is built
for the purpose of producing product or group of products.

3. Process control
• The regulation or manipulation of variables influencing the conduct
of a process in such a way as to obtain a product of desired quality
and quantity in an efficient manner.

4. • Input to process: Mass or energy applied to the process.
• Output of process: The product delivered by the process. This is a
dynamic variable.
• Supply: Source of mass energy input to process.
• Control Valve: Consists of the final actuator and final controlling
elements. This is the forward controlling elements which directly
changes the value of the manipulated variable.
• Load: Anything that affects the value of the controlled variable under a
constant supply input

5. • Open Loop: Control without feedback. Open loop can not cope upsets.
Example of open of open loop. Automatic dishwasher, automatic water
sprinkling system, a control loop with the controller in manual.
• Primary Element: The measuring element that quantitatively converts
the measured variable energy into a from suitable for measurement.
• Transmitter: A transducer which responds to a measured variable by
means of a sensing element, and converts it to a standardized
transmission signal which is a function only of the measured variable.

6. Types of control:-
• Continuous
• Sequential
• Batch
(1) Continuous: Continuous control is used on continuous process.
(2) Sequential: Sequential is often referred to as ON/Off control.
(3) Batch: Batch control is a combination of sequential and continuous
control.

7. • Positive Feedback:
 It can be defined as the control action in which the error is
reinforced until a limit is eventually reaches.
• Negative Feedback:
 It can be defined as the control action in which the error is
minimized made as small as possible, depending on the algorithm
of the controller.

8. Thank you