An Improved Whale Optimization Algorithm Based PIDF–(1+PI) Cascade Automatic Generation Control for Multi-Area Multi-Source Power System With Capacitive Energy Storage

Abstract

Modern power system has complex composition structure and high stability operation requirements. While the emergence of various new energy sources and the uncertainty of external disturbances bring a great challenge to the Automatic Generation Control (AGC) of power system. In order to improve the robustness of the AGC and facilitate the practical engineering application, this paper proposes a novel structure multistage Proportional Integral Derivative (PID) cascade automatic generation controller as well as an improved more effective control parameter optimization algorithm. Firstly, a two-area multi-unit multi-source hydro/thermal power system containing with capacitive energy storage unit is modeled. And using double closed-loops control method, a PID controller with derivative Filter and 1+Proportional Integral unit (PIDF-(1+PI)) cascade automatic generation controller is proposed. Secondly, by introducing a nonlinear time-varying adaptive weight factor, an improved Whale Optimization Algorithm (WOA-w) is proposed to accelerate the convergence speed and enhance the solution accuracy. Then, based on the integral of time multiplied absolute error (ITAE) objective function, the proposed PIDF-(1+PI) controller parameters are optimized by WOA-w. Finally, MATLAB/Simulink software is used to implement the control system multi-case simulation. Compared with other three control strategies, the multi-scenario cases simulation results verify the correctness and effectiveness of the proposed control strategy.

Keywords

• Automatic generation control
• cascade control
• hydro thermal system
• whale optimization algorithm
• capacitive energy storage