Multi-area power systems H∞/μ robust load frequency control

Load frequency control as it is known means how to control the deviation in the plant frequency which happens due to a sudden changes in the power demand. the frequency is one of very important parameters which must be kept with minimum sensitivity to such a perturbations. For this reason the present work deals with studying the different types of feedback controller which has been used such as, H_∞, μ .ect .H_∞-controller design shows good results for fixed operating point conditions, but for variation of the circumstance condition it is not very attractive, while μ - technique show slow conversance to the target. Here a combined H_∞/μ approach has been proposed to design a robust feedback load frequency controller for multi-area power system. The designed controller shows an allow for wide range of variation in parameters up to (± 50%), while the system remains stable. The simulated closed-loop system results where encouragous although this approach suffers from a problem of increasing the dimension of the controller with each extra iteration and the available techniques for order reduction adds a small percent of uncertainties to the results.