This paper presents a photovoltaic (PV)-assisted Unified Power Quality Conditioner (UPQC) for enhancing power quality in grid-connected microgrids. The main novelty lies in the integration of a Sequence-Aware Gated Attention Neural Network (SA-GANN) and a Chaotic Parrot Optimization Algorithm tuned PI (CPOA-PI) controller. Unlike conventional UPQC controllers, the proposed SA-GANN directly learns positive and negative-sequence voltage and current characteristics to generate coordinated reference signals for both series and shunt compensators, eliminating the need for separate sequence extraction and transformation stages. In addition, the CPOA-PI controller provides fast and stable DC-link voltage regulation under dynamic operating conditions. The proposed PV-UPQC system is evaluated in MATLAB/Simulink under no-load, voltage sag, and voltage swell conditions. Simulation results demonstrate effective voltage restoration, harmonic suppression, and DC-link stabilization. The proposed method achieves source current THD values of 1.98%, 2.04%, and 2.50% for the three phases, reduces the voltage unbalance factor to 0.3%, and maintains a power factor of 0.999. The results confirm that the proposed control strategy provides superior power quality enhancement and dynamic performance compared with existing UPQC control approaches.
A unified power quality conditioner (UPQC) is developed for the mitigation of grid-voltage and -current distortions under steady-state and dynamic conditions. The proposed configuration integrates series and shunt inverters through a common DC-link capacitor. The capacitor functions as an energy buffer by accommodating...
Chin-Chan Cheng, Jun-Hao Chen, K. Tan· Energies· 0 citations
Parallel-inverter microgrids are prone to PCC voltage distortion during islanded operation with nonlinear and unbalanced loads. Virtual-impedance methods can reshape inverter output impedance, but they also add control complexity and may introduce extra voltage drops. This paper proposes a droop-based PI-QPR control st...
Jin-Hao Shen, Hua Zhang, Xueneng Su et al.· Applied Sciences· 0 citations
A high penetration of grid-following inverter-based resources can degrade voltage stability because these inverters depend on grid voltage references and provide limited dynamic support during disturbances. This paper proposes a virtual synchronous generator (VSG)-based grid-forming (GFM) inverter controlled by finite...
Budara Abeysinghe, Lishani Walpita, Vishwa Vincent et al.· Moratuwa Engineering Researc...· 0 citations
Traditional unified power quality conditioner (UPQC) only relies on DC-side capacitors for energy storage, which leads to severe DC bus voltage fluctuation, steady-state AC tracking error of series-side voltage compensation, and insufficient energy supply for long-duration compensation under deep voltage sag conditions...
Xiu-Ying Mo, Jiang Zeng· 2026 6th International Confe...· 0 citations
In order to improve power quality in low-voltage distribution networks with nonlinear, distorted, and unbalanced loads, this research suggests an innovative design for Shunt Active Power Filters (SAPFs). Compared to conventional single-inverter SAPF structures, the improved method uses a combination of two T-Type three...
Mohamed Djelbane, Mohamed Elbar, N. Charrak et al.· Energies· 0 citations
In grid- connected applications featuring a large share of renewable generation, the output fluctuations of photovoltaic (PV) generation deteriorate the power quality of grid-connected systems, and the improper power allocation within the hybrid energy storage system (HESS) further degrades the operational performance....
Yu-Yan Liu, Yi-Hua Zhu, Chao Luo et al.· International Conference on...· 0 citations
We use cookies to run the site and, with your consent, for analytics and to show ads.
See our Cookie Policy.
