Development of sigmoid based nonlinear controllers in a PID framework for load frequency stabilization.

Area of Science:

• Electrical Engineering
• Control Systems
• Power Systems

Background:

• Power system frequency stabilization is crucial for grid reliability.
• Traditional Proportional-Integral-Derivative (PID) controllers have limitations in handling nonlinearities and noise.
• Nonlinear transformations of Area Control Error (ACE) offer potential for improved control.

Purpose of the Study:

• To propose and evaluate novel nonlinear controllers for power system frequency stabilization.
• To investigate the efficacy of Sigmoid-transformed PID (STPID), TanSig PID (TSPID), and TanSig PI-TanSig PD (TSPI-TSPD) controllers.
• To assess the performance of these controllers under various conditions, including measurement noise.

Main Methods:

• Development of STPID, TSPID, and TSPI-TSPD controllers utilizing hyperbolic tangent functions for nonlinear ACE transformation.
• Inspiration from Fuzzy PID (FPID) controller structures.
• Validation on power system test models.
• Stability analysis using Bode plots.
• Real-time simulation using the OPAL-RT platform.
• Parameter tuning using the Giza Pyramids Construction (GzPC) metaheuristic algorithm.

Main Results:

• Proposed controllers demonstrated encouraging results in power system frequency stabilization.
• The TSPID controller exhibited highly satisfying performance, especially in the presence of measurement noise.
• Integration of an anti-windup mechanism further improved controller outcomes.
• Real-time simulations confirmed the effectiveness of the proposed methods.

Conclusions:

• The novel nonlinear controllers, particularly TSPID, offer a promising approach for robust power system frequency stabilization.
• The nonlinear transformation of ACE effectively enhances controller performance.
• The GzPC algorithm provides an efficient method for tuning controller parameters.