Essam El-Din Mohamed Aboul Zahab

This paper presents a novel contribution of a low complexity control scheme for voltage control of a dynamic voltage restorer (DVR). The scheme proposed utilizes an error-driven proportional–integral–derivative (PID) controller to guarantee better power quality performance in terms of voltage enhancement and stabilization of the buses, energy efficient utilization, and harmonic distortion reduction in a distribution network. This method maintains the load voltage close to or equal to the nominal value in terms of various voltage disturbances such as balanced and unbalanced sag/swell, voltage imbalance, notching, different fault conditions as well as power system harmonic distortion. A grasshopper optimization algorithm (GOA) is used to tune the gain values of the PID controller. In order to validate the effectiveness of the proposed DVR controller, first, a fractional order PID controller was presented and compared with the proposed one. Further, a comparative performance evaluation of four optimization techniques, namely Cuckoo search (CSA), GOA, Flower pollination (FBA), and Grey wolf optimizer (GWO), is presented to compare between the PID and FOPID performance in terms of fault conditions in order to achieve a global minimum error and fast dynamic response of the proposed controller. Second, a comparative analysis of simulation results obtained using the proposed controller and those obtained using an active disturbance rejection controller (ADRC) is presented, and it was found that the performance of the optimal PID is better than the performance of the conventional ADRC. Finally, the effectiveness of the presented DVR with the controller proposed has been assessed by time-domain simulations in the MATLAB/Simulink platform.

This paper presents a novel stabilization FACTS-based scheme that acts as a switched compensator for grid-connected wind energy systems. It is a member of a family of devices and switched dynamic voltage stabilization converters that were developed to ensure minimal loss of excitation, voltage stabilization, energy efficient utilization, power quality enhancement and harmonic distortion reduction in AC distribution grid networks. A novel-dual action distributed FACTS based–switched power filter compensator (SPFC) scheme is developed for efficient utilization of wind energy under varying wind conditions and major load excursions. A dynamic multi-level error-driven decoupled time de-scaled multi regulation control strategy is used to guarantee better power quality performance in terms of voltage enhancement and stabilization of the AC buses, improvement of power factor, and harmonic distortion reduction. The proposed SPFC was controlled using an inter-coupled weighted modified proportional-integral-derivative (WM-PID) controller. Cuckoo search (CS) optimization algorithm is employed to get the PID controller gains in terms of variations and excursions in wind speed and dynamic load excursions to reflect the performance of the compensator scheme. The effectiveness of the proposed SPFC with the multi-level control strategy has been assessed by time-domain simulations in Matlab/Simulink environment. The results obtained show the robustness of the proposed topology.