The application of genetic algorithms to gain-scheduling controller analysis and design

Gain scheduling is an acknowledged design technique for the control of nonlinear systems. It operates by switching between a network of linear controllers according to the system operating point. The genetic algorithm (GA) can be applied to the design of such a network. The GA is used to optimise the activation points of the individual controllers. GA coding for such a scheduling problem is discussed. An exhaustive search to establish the optimum number of controllers coupled with optimisation of the corresponding activation points by GA shows the relationship between controller performance and complexity. The GA designed gain scheduling network is compared with another gain scheduling design technique and the activation points identified by GA are used to determine the degree of nonlinearity of the plant throughout its operating region.