Control theory normally starts with continuous time systems on the 's' domain to move on to the discrete time and the 'z' domain, where most of the actual digital systems fall in. In this article I will show how easy is to write a Vivado HLS function implementing a discrete time PID, plus a testbench to simulate its behaviour with a given plant transfer function. Understanding them well is basic to proceed to more elaborate schemes.
PID controllers are a classic in control theory textbooks and the starting point of control engineers education.
PID is an acronym for Proportional - Integral - Derivative and actually refers to a type of controller widely used in a wide range of applications to control a system (typically called 'plant') to have its output closely following an input reference value (called 'set point').Ĭontrol engineering is a fascinating and complex field yet it is relatively old, with its beginnings as far back as the Watt's regulator although most of the modern development was done in the 50s of last century. The Proportional-Integral-Derivative (PID) controller and its variants are simple to construct but they have the propensity to collapse under nonlinear.
