What is a Controller?In control systems, a controller is a mechanism that seeks to minimize the difference between the actual value of a system (i.e. the process variable) and the desired value of the system (i.e. the setpoint). Controllers are a fundamental part of control engineering and used in all complex control systems.Before we introduce you to various controllers in detail, it is essential to know the uses of controllers in the theory of control systems. The important uses of the control

A control system is a system of devices that manages, commands, directs or regulates the behavior of other devices to achieve a desired result. In other words, the definition of a control system can be simplified as a system which controls other systems to achieve a desired state. There are various types of control systems, which can be broadly categorised as linear control systems or non-linear control systems. These types of control systems are discussed in detail below.Linear Control SystemsI

What is a Control System?A control system is defined as a system of devices that manages, commands, directs, or regulates the behavior of other devices or systems to achieve a desired result. A control system achieves this through control loops, which are a process designed to maintain a process variable at a desired set point.In other words, the definition of a control system can be simplified as a system, which controls other systems. As human civilization is being modernized day by day the de

What is an On Off Controller?Sometimes, the control element has only two positions either it is fully closed or fully open. This control element does not operate at any intermediate position, i.e. partly open or partly closed position. The control system made for controlling such elements is known as the on-off control theory. In this control system, when process variable changes and crosses a certain preset level, the output value of the system is suddenly fully opened and gives 100 % output.Ge

AC Induction motors offer enviable operational characteristics such as robustness, reliability and ease of control. They are extensively used in various applications ranging from industrial motion control systems to home appliances. However, the use of induction motors at its highest efficiency is a challenging task because of their complex mathematical model and non-linear characteristic during saturation. These factors make the control of induction motor difficult and call for the use of a hig

What is Control EngineeringControl system engineering is the branch of engineering which deals with the principles of control theory, to design a system which gives yields the desired behavior in a controlled manner. Hence, although control engineering is often taught within electrical engineering at university, it is an interdisciplinary topic.Control system engineers analyze, design, and optimize complex systems which consist of highly integrated coordination of mechanical, electrical, chemica

What is Nyquist Stability Criterion?Nyquist stability criterion (or Nyquist criteria) is defined as a graphical technique used in control engineering for determining the stability of a dynamical system. As Nyquist stability criteria only considers the Nyquist plot of open-loop control systems, it can be applied without explicitly computing the poles and zeros of either the closed-loop or open-loop system.As a result, Nyquist criteria can be applied to systems defined by non-rational functions (s

What is SCADA?SCADA stands for “Supervisory Control and Data Acquisition.” SCADA is a process control system architecture that uses computers, networked data communications, and graphical Human Machine Interfaces (HMIs) to enable high-level process supervisory management and control.SCADA systems communicate with other devices, such as programmable logic controllers (PLCs) and PID controllers to interact with industrial process plants and equipment.SCADA systems form a large part of control syst

What is a PLC?PLC stands for “Programmable Logic Controller.” A PLC is a computer specially designed to operate reliably in harsh industrial environments, such as extreme temperatures and wet, dry, and/or dusty conditions. PLCs are used to automate industrial processes such as a manufacturing plant’s assembly line, an ore processing plant, or a wastewater treatment plant.PLCs share many features of the personal computer you have at home. They both have a power supply, a CPU (Central Processing U

What is Steady State Error?Steady-state error is defined as the difference between the desired value and the actual value of a system output in the limit as time goes to infinity (i.e. when the response of the control system has reached steady-state).Steady-state error is a property of the input/output response for a linear system. In general, a good control system will be one that has a low steady-state error.First, we will discuss the steady-state error in a first-order transfer function by an