Fundamentals of PID Control
Anthony K. Ho, P.E.
The course starts by introducing the basic theory behind PID control. Then, it is followed by two major types of controls: open-loop and close loop controls. Tuning the three constants in the PID controller algorithm is a very important concept of any PID application; therefore, PID tuning will be focused. Examples will be used throughout the course for engineers to understand the steps to implement and tune PID controllers.
The intention of this course is to help you understand how most PID controllers work, which will provide you the basic knowledge to perform the task.
At the conclusion of this course, the student will acquire the following specific knowledge and skills:
This course is intended for control systems, electrical, and industrial engineers.
Benefit for Attendee
Attendee of this course will be able to understand the concept of PID control application and the steps to implement and tune PID controllers.
PID control is used to control and maintain processes. It can be used to control physical variables such as temperature, pressure, flow rate, and tank level. The technique is widely used in today’s process industry to achieve accurate control under different process conditions. PID is an algorithm that the controller uses to evaluate the controlled variables.
The course content is contained in the following PDF file:
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The proportional, integral, and derivative terms are used to calculate the output of the PID controller. Therefore, the proportional, integral, and derivative gains must be chosen correctly for the control loop to be stable. The process of adjusting these control parameters to the optimum values is called tuning the control loop. Stability is a basic requirement, if the parameters are chosen incorrectly, the controlled process input can become unstable, i.e. its output diverges, with or without oscillation, and is limited only by saturation or mechanical breakage. Instability is caused by excess gain, particularly in the presence of significant lag. Performance can generally be improved by careful tuning. PID tuning is a difficult problem, even though there are only three parameters and in principle is simple to describe, because it must satisfy complex criteria within the limitations of PID control. There are various methods for loop tuning, and more sophisticated techniques are provided by different PLC controller vendors. This course describes most common methods for loop tuning.
For additional technical information related to this subject, please visit the following websites or web pages:
Control Tutorials for Mathlab: PID Tutorial
Proportional-Integral-Derivative PID Controls
Virtual PID Controller Laboratory : PID Design & Tuning