Overcoming challenges of PID control & analyzer applications An enhanced PID controller simplifies tuning and improves loop stability and reliability for loops dominated by discontinuous measuremen...
Temperature Control Using Analog PID Controller. Project Report for Final Year Engineering Students. The objective of our project is maintaining the temperature constant in a particular a…Descripción completa
Design of a PID controller using Matlab and LabVIEW
Theory PID controller in a closed loop control system is shown in figure1. A proportional– integral–derivative controller (PID controller) is a controller which is popularly used in industrial control systems. It is fed with the error signal, that is, the difference between the reference, or the desired output and the actual output (which is obtained as a feedback). The controller then attempts to bring the actual output to track the reference. The inherent simplicity in design and understanding has made it a widely used controller. The input from the PID controller to a system is given by the equation , •
=Proportional gain
• •
=Derivative gain =Integral gain
The PID controller is a combination of three terms namely the gain, derivative and integral terms. The importance of each term is discussed briefly. The proportional gain, when varied changes the location of poles and zeros of the system. Therefore, the system’s behavior is dependent on the value of gain K. Consequently, it is possible to select (design) a value for the gain that makes the system behave in a desired manner. Proportional controllers are the simplest controllers and are very common. We only need to change the amplification value of a controller that already exists without having to add anything to the system. However, it is not always possible to find appropriate pole locations with proportional controllers so we move to other type of controllers. Introducing high gain induces faster response but comprises on overshoot and error values. Hence to achieve reduced steady state error an integral term is introduced in addition to the proportional term thereby improving the system response. In order to meet the design requirements in the real an additional term, that is, the derivative is introduced thereby controlling the dynamic behavior of a system. The transfer function of the PID controller is /
This error signal (e) will be sent to the PID controller, and the controller output is obtained.
Mathematical Formulation The gain for the proportional part is calculated using
The derivative gain is
The integral gain is
1
Procedure All pre-assignments must be done in the lab book (of each student) and will be marked during the practical session. Each member of the group must participate in the preparation. Step1: Make the circuit as shown in figure2. Step 2: Apply a step input of very low amplitude at the input terminal. Step3: Capture the output response of the signal of the PID controller in DSO.
