Design of Cascaded Controllers for DC Drives using Evolutionary Algorithms

In this paper, we describe a new design procedure for cascaded controller for electrical drives based on evolutionary algorithms. Most electric drives have two separate controllers for current and speed control, which are in general designed in two consecutive steps (firstly the current controller and then the speed one). Using a hybrid evolutionary algorithm designed to test and compare controllers of different orders, we search simultaneously for the couple of discrete anti-windup controllers achieving the optimal compromise of cost and performance indices related to both current and speed responses. Simulation comparison with conventional design techniques on a non-linear DC drive with variable load are presented to show the effectiveness of the approach.