Application of describing function method and active disturbance rejection in LFC systems with nonlinear characteristics

Abstract

In load frequency control (LFC) systems, the presence of governor dead zones and generation rate constraint is a common problem which can affect the dynamic response of the system and even make it unstable. To improve the stability of load frequency control systems with governor dead zone or generation rate constraint (GRC). In this paper, an error compensation strategy is proposed in conjunction with the linear active disturbance rejection control (LADRC) technique, and then the reliability of the system is analyzed using the descriptive function method to obtain a range of values for the compensation coefficients. It is found that the error compensation strategy proposed in this paper can well recover and improve the control performance of the system, at the same time, it is feasible and effective to obtain a range of values for the compensation factor by means of the descriptive function method.

Keywords

• Generation rate constraint
• Linear active disturbance rejection control
• Error compensation scheme