Green Energy
- Ratio Control Loops
Ratio Control Loops - Based on hardware, ratio control is quite often confused with cascade control. The basic operation of ratio control, however, is quite different. - Ratio control is often associated with process operations in which two or more...
- Cascade Control Loops
Cascade Control Loops -The general concept of cascade control is to place one feedback loop inside another. In effect, one takes the process being controlled and finds some intermediate variable within the process to use as the set point for the main...
- Elements Of A Process Control System
Elements of a Process Control System INTRODUCTION-The term automatic process control came into wide use when people learned to adapt automatic regulatory procedures to manufacture products or process material more efficiently. Such procedures are called...
- Boiler Control Theory (feed Water Control)
Boiler Control Theory (Feed water Control) The feed water is controlled to keep the drum level . Water-level controls continuously monitor the level of water in a steam boiler in order to control the flow of feed water into the boiler and to protect...
- Advanced Process Controller (apc) For Controlling Steam Power Plant {part 1}.
"Control of Steam Power Plant is very big job need Care to fulfill the appropriate degree of stability and dependability for such this big system " In many countries, plants have to fulfill specific requirements of the electrical grid (such as frequency...
Green Energy
Feed Forward Control Loops
Feed Forward Control Loops
-A feedback control loop is reactive in nature and represents a response to the effect of a load change or upset. A feedforward control loop, on the other hand, responds directly to load changes and thus provides improved control.
-In feedforward control, a sensor is used to detect process load changes or disturbances as they enter the system. A block diagram of a typical feed- forward control loop is shown in the following Figure. Sensors measure the values of the load variables, and a computer calculates the correct control signal for the existing load conditions and process set point.
-Feedforward control poses some significant problems. Its configuration assumes that the disturbances are known in advance, that they will have sensors associated with them, and that no important undetected disturbances will occur.
-Therefore, feedforward control is more complicated and more expensive, and it requires the operator to have a better understanding of the process than does a standard feedback control loop. So, feedforward control is generally reserved for well-understood and critical applications.
- Ratio Control Loops
Ratio Control Loops - Based on hardware, ratio control is quite often confused with cascade control. The basic operation of ratio control, however, is quite different. - Ratio control is often associated with process operations in which two or more...
- Cascade Control Loops
Cascade Control Loops -The general concept of cascade control is to place one feedback loop inside another. In effect, one takes the process being controlled and finds some intermediate variable within the process to use as the set point for the main...
- Elements Of A Process Control System
Elements of a Process Control System INTRODUCTION-The term automatic process control came into wide use when people learned to adapt automatic regulatory procedures to manufacture products or process material more efficiently. Such procedures are called...
- Boiler Control Theory (feed Water Control)
Boiler Control Theory (Feed water Control) The feed water is controlled to keep the drum level . Water-level controls continuously monitor the level of water in a steam boiler in order to control the flow of feed water into the boiler and to protect...
- Advanced Process Controller (apc) For Controlling Steam Power Plant {part 1}.
"Control of Steam Power Plant is very big job need Care to fulfill the appropriate degree of stability and dependability for such this big system " In many countries, plants have to fulfill specific requirements of the electrical grid (such as frequency...