Design of a robust load frequency control using sequential quadratic programming technique

This paper presents a new methodology, named Sequential Quadratic Programming (SQP), to design a robust PID controller for Load Frequency Control (LFC) of nonlinear interconnected power systems. This method easily copes with the nonlinear constraints such as Generation Rate Constraint (GRC) and it can be directly used on a nonlinear model of a multi-machine power system. The proposed controller is simple, effective and can ensure that the overall system performance is desirable. The robust performance of the proposed controller is compared with that of a conventional PI controller, and also with two other different techniques named PID-MPRS and PID-PSO through the simulation of two multi-machine power system examples with a variety of disturbances. Results show that the proposed technique gives a better performance. (C) 2011 Elsevier Ltd. All rights reserved.