Feedback Of A Control System

Electrical Electronics Engineering

Feedback in a control system refers to the mechanism where a portion of the output is “fed back” to the input for comparison with the desired reference signal, enabling adjustments to the system’s behavior. It plays a crucial role in enhancing stability, accuracy, and performance. Feedback mechanisms can be classified into negative feedback, which reduces the system’s deviation from the desired state, and positive feedback, which amplifies deviations. Negative feedback is widely utilized in control systems due to its stabilizing effect, ensuring that the system maintains desired performance despite disturbances or changes in operating conditions. Through careful design and implementation, feedback control systems can achieve precise regulation, robustness against disturbances, and improved transient response, making them indispensable in various applications ranging from industrial processes to aerospace systems. Understanding and optimizing feedback mechanisms are essential for enhancing system efficiency, reliability, and adaptability, thereby driving advancements in control theory and engineering practices.

TABLE OF CONTENT

COVER PAGE

APPROVAL PAGE

DEDICATION

ACKNOWLEDGEMENT

TABLE OF CONTENT

INTRODUCTION
BACKGROUND OF THE STUDY
AIMS AND OBJECTIVE
SCOPE OF THE STUDY
METHODOLOGY
OUTLINE OF THE STUDY

CHAPTER TWO

LITERATURE REVIEW

CONCEPTUAL REVIEW
WHAT IS A CONTROL SYSTEM
FUNCTION OF A CONTROL SYSTEM
ADVANTAGES AND DISADVANTAGES OF A CONTROL SYSTEM
ISSUES FACING FEEDBACK IN A CONTROL SYSTEM
SIGNAL AND SYSTEM

CHAPTER THREE

DESIGN METHODOLOGY

3.1 DESIGN AND ANALYSIS OF A CONTROL SYSTEM

3.2 FEED FORWARD AND FEED BACK CONTROL PERFORMANCE ANALYSIS

3.3 FEEDBACK CONTROL METHODOLOGIES FOR NON LINEAR SYSTEM

3.4 FEEDBACK CONTROL TECHNIQUES FOR NON LINEAR ANALYTIC SYSTEM

CHAPTER FOUR

4.0 DESIGN AND IMPLEMENTATION

4.1 NOMINAL STABILITY AND PERFORMANCE OF A FEEDBACK CONTROL SYSTEM

4.2 DIAGNOSIS OF A CURRENT SITUATION

4.3 CONCLUSION

CHAPTER ONE

INTRODUCTION
- BACKGROUND OF THE STUDY

Control theory deals with the control of dynamical systems in engineered processes and machines. The objective is to develop a control model for controlling such systems using a control action in an optimum manner without delay or overshoot and ensuring control stability.

To do this, a controller with the requisite corrective behavior is required. This controller monitors the controlled process variable (PV), and compares it with the reference or set point (SP). The difference between actual and desired value of the process variable, called the error signal, or SP-PV error, is applied as feedback to generate a control action to bring the controlled process variable to the same value as the set point. Other aspects which are also studied are controllability and observability. This is the basis for the advanced type of automation that revolutionized manufacturing, aircraft, communications and other industries. This is feedback control, which involves taking measurements using a sensor and making calculated adjustments to keep the measured variable within a set range by means of a “final control element”, such as a control valve.

Feedback Systems process signals and as such are signal processors. The processing part of a feedback system may be electrical or electronic, ranging from a very simple to a highly complex circuits.

Simple analogue feedback control circuits can be constructed using individual or discrete components, such as transistors, resistors and capacitors, etc, or by using microprocessor-based and integrated circuits (IC’s) to form more complex digital feedback systems.

As we have seen, open-loop systems are just that, open ended, and no attempt is made to compensate for changes in circuit conditions or changes in load conditions due to variations in circuit parameters, such as gain and stability, temperature, supply voltage variations and/or external disturbances. But the effects of these “open-loop” variations can be eliminated or at least considerably reduced by the introduction of Feedback.

A feedback system is one in which the output signal is sampled and then fed back to the input to form an error signal that drives the system. In the previous tutorial about Closed-loop Systems, we saw that in general, feedback is comprised of a sub-circuit that allows a fraction of the output signal from a system to modify the effective input signal in such a way as to produce a response that can differ substantially from the response produced in the absence of such feedback.

Feedback Systems are very useful and widely used in amplifier circuits, oscillators, process control systems as well as other types of electronic systems. But for feedback to be an effective tool it must be controlled as an uncontrolled system will either oscillate or fail to function.

AIMS AND OBJECTIVE

The main aim of the study is to carry out the research on the role of feedback of a control system. The control system used is to ensure that the steady state value of the variable is equal to the reference value. The following objective shall be achieved:

Know the definition of the following terms: input, output, feedback, error, open loop, and closed loop.
Understand the principle of closed-loop control.
Understand how the following processes are related to the closed-loop method of control: position feedback, rate feedback, and acceleration feedback.
Understand the principle of damping and its effect upon system operation.
Be able to explain the advantages of closed-loop control.

SCOPE OF THE STUDY

In a control system, If either the output or some part of the output is returned to the input side and utilized as part of the system input, then it is known as feedback. Feedback plays an important role in order to improve the performance of the control systems. In this work, we are writing on the role of feedback in a control system

METHODOLOGY

In the course of carrying this study, numerous sources were used which most of them are by visiting libraries, consulting journal and news papers and online research which Google was the major source that was used.

OUTLINE OF THE STUDY

The work is organized as follows: chapter one discuses the introductory part of the work, chapter two presents the literature review of the study, chapter three describes the methods applied, chapter four discusses the results of the work, chapter five summarizes the research outcomes and the recommendations.