project maker
09-08-2014, 02:48 PM
Controller Designing Of MIMO System
[attachment=66811]
1. ABSRACT
In this paper, some information about the MIMO system, its transfer functions and block diagram is given. In addition, problems related to MIMO systems such as process interactions are presented. Also different strategies such as decoupling method, to reduce these control interactions are presented. Finally, relative gain array (RGA) is applied here for pairing of manipulated and controlled variable to get a desired output.
INTRODUCTION:
A control system consists of subsystems and processes (or plants) assembled for the purpose of obtaining a desired output with desired performance, given a specified input. Figure 1 shows a control system in its simplest form, where the input represents a desired output.
ADVANTAGES OF CONTROL SYSTEM:
With control systems we can move large equipment with precision that would otherwise be impossible. We can point huge antennas toward the farthest reaches of the universe to pick up faint radio signals, controlling these antennas by hand would be impossible. Because of control systems, elevators carry us quickly to our destination, automatically stopping at the right floor (Figure 1.3). We alone could not provide the power required for the load and the speed; motors provide the power, and control systems regulate the position and speed.
We build control systems for four primary reasons:
1. Power amplification
2. Remote control
3. Convenience of input form
4. Compensation for disturbances
Robots designed by control system principles can compensate for human disabilities. Control systems are also useful in remote or dangerous locations. For example, a remote-controlled robot arm can be used to pick up material in a radioactive environment.
Control systems can also be used to provide convenience by changing the form of the input. For example, in a temperature control system, the input is a position on a thermostat. The output is heat. Thus, a convenient position input yields a desired thermal output.
Another advantage of a control system is the ability to compensate for disturbances. Typically, we control such variables as temperature in thermal systems, position and velocity in mechanical systems, and voltage, current, or frequency in electrical systems. The system must be able to yield the correct output even with a disturbance. For example, consider an antenna system that point in a commanded direction. If wind forces the antenna from its commanded position, or if noise enters internally, the system must be able to detect the disturbance and correct the antenna's position. Obviously, the system's input will not change to make the correction. Consequently, the system itself must measure the amount that the disturbance has repositioned the antenna and then return the antenna to the position commanded by the input.
AUTOMATIC CONTROL SYSTEM
A machine (or system) work by machine-self, not by manual operation. Automatic control is the application of control theory for regulation of processes without direct human intervention. Automatic control can self-regulate a technical plant (such as a machine or an industrial process) operating condition or parameters by the controller with minimal human intervention. A regulator such as a thermostat is an example of a device studied in automatic control
MULTIPLE INPUT MULTIPLE OUTPUT (MIMO) SYSTEM:
MIMO control system is a Manipulated Input Manipulated Output system. In this type of system more than one controlled variables are applied into the process and get more than one output. The main difference between a scalar (SISO) system and a MIMO system is the presence of directions. Directions are relevant for vectors and matrices, but not for scalars. In many practical control problems typically a number of process variables which must be controlled and number of variables which can be manipulated, these problems are referred to as MIMO System. The application of MIMO system is inverted pendulum, aircraft control, and four tank controls.
CONCLUSION
In this project we have considered control problems with multiple inputs (manipulated variable) and multiple outputs (controlled variable) using a set of single-loop controllers (multiloop control). Such MIMO control problems are more difficult than SISO control problems due to the presence of process interactions. They produce undesirable control loop interactions for multiloop control. If these interactions are unacceptable, then different model-based multivariable control strategies are taken. One such is the decoupling method which is used to reduce the control loop interactions.
In MIMO system another problem is that on changing the input variable (manipulated variable) output variable (controlled variable) also changes. So relative gain array (RGA) is used for pairing the manipulated and controlled variable to get a desired output.
In this phase we have studied upto this and in our next phase we want to design a controller on MIMO and implement this on MATLAB simulink.
[attachment=66811]
1. ABSRACT
In this paper, some information about the MIMO system, its transfer functions and block diagram is given. In addition, problems related to MIMO systems such as process interactions are presented. Also different strategies such as decoupling method, to reduce these control interactions are presented. Finally, relative gain array (RGA) is applied here for pairing of manipulated and controlled variable to get a desired output.
INTRODUCTION:
A control system consists of subsystems and processes (or plants) assembled for the purpose of obtaining a desired output with desired performance, given a specified input. Figure 1 shows a control system in its simplest form, where the input represents a desired output.
ADVANTAGES OF CONTROL SYSTEM:
With control systems we can move large equipment with precision that would otherwise be impossible. We can point huge antennas toward the farthest reaches of the universe to pick up faint radio signals, controlling these antennas by hand would be impossible. Because of control systems, elevators carry us quickly to our destination, automatically stopping at the right floor (Figure 1.3). We alone could not provide the power required for the load and the speed; motors provide the power, and control systems regulate the position and speed.
We build control systems for four primary reasons:
1. Power amplification
2. Remote control
3. Convenience of input form
4. Compensation for disturbances
Robots designed by control system principles can compensate for human disabilities. Control systems are also useful in remote or dangerous locations. For example, a remote-controlled robot arm can be used to pick up material in a radioactive environment.
Control systems can also be used to provide convenience by changing the form of the input. For example, in a temperature control system, the input is a position on a thermostat. The output is heat. Thus, a convenient position input yields a desired thermal output.
Another advantage of a control system is the ability to compensate for disturbances. Typically, we control such variables as temperature in thermal systems, position and velocity in mechanical systems, and voltage, current, or frequency in electrical systems. The system must be able to yield the correct output even with a disturbance. For example, consider an antenna system that point in a commanded direction. If wind forces the antenna from its commanded position, or if noise enters internally, the system must be able to detect the disturbance and correct the antenna's position. Obviously, the system's input will not change to make the correction. Consequently, the system itself must measure the amount that the disturbance has repositioned the antenna and then return the antenna to the position commanded by the input.
AUTOMATIC CONTROL SYSTEM
A machine (or system) work by machine-self, not by manual operation. Automatic control is the application of control theory for regulation of processes without direct human intervention. Automatic control can self-regulate a technical plant (such as a machine or an industrial process) operating condition or parameters by the controller with minimal human intervention. A regulator such as a thermostat is an example of a device studied in automatic control
MULTIPLE INPUT MULTIPLE OUTPUT (MIMO) SYSTEM:
MIMO control system is a Manipulated Input Manipulated Output system. In this type of system more than one controlled variables are applied into the process and get more than one output. The main difference between a scalar (SISO) system and a MIMO system is the presence of directions. Directions are relevant for vectors and matrices, but not for scalars. In many practical control problems typically a number of process variables which must be controlled and number of variables which can be manipulated, these problems are referred to as MIMO System. The application of MIMO system is inverted pendulum, aircraft control, and four tank controls.
CONCLUSION
In this project we have considered control problems with multiple inputs (manipulated variable) and multiple outputs (controlled variable) using a set of single-loop controllers (multiloop control). Such MIMO control problems are more difficult than SISO control problems due to the presence of process interactions. They produce undesirable control loop interactions for multiloop control. If these interactions are unacceptable, then different model-based multivariable control strategies are taken. One such is the decoupling method which is used to reduce the control loop interactions.
In MIMO system another problem is that on changing the input variable (manipulated variable) output variable (controlled variable) also changes. So relative gain array (RGA) is used for pairing the manipulated and controlled variable to get a desired output.
In this phase we have studied upto this and in our next phase we want to design a controller on MIMO and implement this on MATLAB simulink.