pid control of 2nd order mass force system labview vi download

The controller can also be parameterized as u(t) = k p ( e(t) + T i t ) de(t) e(τ)dτ + T d, (.2) dt where T i is the integral time constant and T d the derivative time constant. The controller parameters are proportional gain k p, integral gain k i and derivative gain k d. The control signal is thus a sum of three terms: a proportional term that is proportional to the error, an integral term that is proportional to the integral of the error, and a derivative term that is proportional to the derivative of the error. The reference value, r, is also called the setpoint. The Controller The ideal version of the PID controller is given by the formula u(t) = k p e(t) + k i t e(τ)dτ + k d de dt, (.) where u is the control signal and e is the control error (e = r y). PID CONTROL Error Present Past Future t t + T d Time Figure.: A PID controller takes control action based on past, present and prediction of future control errors. Finally we will also discuss implementation of PID controllers, similar methods can be used to implement many other controllers. Methods to avoid windup will also be presented. This phenomenon that occurs in practically all control systems will be discussed in depth for PID controllers. In combinations with controllers having integral actions saturations give rise to an effect called integral windup. However, there is one nonlinear effect, that has to be considered in most control systems namely that actuators saturate. Many aspects of control can be understood based on linear analysis. In this chapter we discuss the basic ideas of PID control and the methods for choosing the parameters of the controllers. Most controllers do not use derivative action. In engineering applications the controllers appear in many different forms: as a stand alone controller, as part of hierarchical, distributed control systems, or built into embedded components. PID controllers are commonly used in industry and a large factory may have thousands of them, in instruments and laboratory equipment. PID control is by far the most common way of using feedback in natural and man-made systems. 1 Chapter PID Control Based on a survey of over eleven thousand controllers in the refining, chemicals and pulp and paper industries, 97% of regulatory controllers utilize PID feedback.

Pid control of 2nd order mass force system labview vi download