ANFIS and fuzzy tuning of PID controller for STATCOM to enhance power quality in multi-machine system under large disturbance

Abstract

STATCOM is one of the FACTS devices that are used in power systems. The algorithms used to control the STATCOM often use PID controller. However, there are a lot of elements in the network and have complex configurations and their dynamic model is highly non-linear, and convention PID controller are not robust for their stability control. In this paper, we propose the intelligent controllers for STATCOM based on dynamic model of the system and two control schemes have been developed: (i) Fuzzy-PID self-tuning controller (Hybrid F-PID); (ii) Adaptive neuro-fuzzy inference system – PID (ANFIS-PID) controller. The operating performance of the studied system is using the popular benchmark three-machine nine-bus system. The two-axis four-order model of synchronous generator (SG) is used. Time-domain scheme based on a nonlinear system model subject to a three-phase short-circuit fault at the load connected bus is utilized to examine the effectiveness of the proposed control schemes. It can be concluded from the simulation results that ANFIS has provide the best results for controlling STATCOM to enhance power quality in power system as compared to the conventional control strategies under large disturbance.