Neural-Network-Based Terminal Sliding Mode Control for Frequency Stabilization of Renewable Power Systems

This paper addresses a terminal sliding mode control(T-SMC) method for load frequency control(LFC) in renewable power systems with generation rate constraints(GRC).A two-area interconnected power system with wind turbines is taken into account for simulation studies. The terminal sliding mode controllers are assigned in each area to achieve the LFC goal. The increasing complexity of the nonlinear power system aggravates the effects of system uncertainties. Radial basis function neural networks(RBF NNs) are designed to approximate the entire uncertainties. The terminal sliding mode controllers and the RBF NNs work in parallel to solve the LFC problem for the renewable power system. Some simulation results illustrate the feasibility and validity of the presented scheme.

Novel chaos game optimization tuned-fractional-order PID fractional-order PI controller for load-frequency control of interconnected power systems

In this work,chaos game optimization(CGO),a robust optimization approach,is employed for efficient design of a novel cascade controller for four test systems with interconnected power systems(IPSs)to tackle load-frequency con-trol(LFC)difficulties.The CGO method is based on chaos theory principles,in which the structure of fractals is seen via the chaotic game principle and the fractals’self-similarity characteristics are considered.CGO is applied in LFC studies as a novel application,which reveals further research gaps to be filled.For practical implementation,it is also highly desirable to keep the controller structure simple.Accordingly,in this paper,a CGO-based controller of fractional-order(FO)proportional-integral-derivative-FO proportional-integral(FOPID-FOPI)controller is proposed,and the integral time multiplied absolute error performance function is used.Initially,the proposed CGO-based FOPID-FOPI controller is tested with and without the nonlinearity of the governor dead band for a two-area two-source model of a non-reheat unit.This is a common test system in the literature.A two-area multi-unit system with reheater-hydro-gas in both areas is implemented.To further generalize the advantages of the proposed scheme,a model of a three-area hydrothermal IPS including generation rate constraint nonlinearity is employed.For each test system,comparisons with relevant existing studies are performed.These demonstrate the superiority of the proposed scheme in reducing settling time,and frequency and tie-line power deviations.