Nowadays, power quality under the excessive implementation of power electronics devices is quite challenging issue. The compensation of non-sinusoidal; reactive and harmonic; components is the main role for power quality devices which highly depend on the robustness of the control system. Some common control systems are implemented using Synchronous Stationary Frame (DQ) theory. This paper proposes a new version of DQ control technique to control dynamic voltage restorer under severe transient voltage conditions. The power system network with the new DQ control technique is studied and analyzed under different scenarios to compensate for severe balanced and unbalanced voltage sags and swells. This new scheme is based on extraction of positive sequence components to implement the control algorithm. A mathematical model of the dynamic voltage restorer (DVR), hysteresis voltage control, converter controller model, new DQ scheme with complete system equations are carried out and verified using Simulink / MATLAB. The proposed system is validated experimentally using DSpace 1104 based laboratory system. The obtained results of the proposed compensation algorithm are compared with the results obtained from the traditional DQ method. Simulation and experimental results are correlated and show effectiveness of the proposed DQ control scheme.

In today’s power system, power quality is a critical topic having several impacts on customers and utilities. In the current electric power system, the integration of renewable energy sources, smart grid technologies, and significant usage of power electronics equipment has generated a slew of issues. The sensitive equipment might be damaged by harmonics, voltage sag, and swell. These devices are vulnerable to Interference with other elements of the system resulting in input voltage changes. As a result, in the contemporary period, Power quality is becoming more important as the number of sensitive and costly electronic devices grows. To overcome the challenges of non-standard voltage, the Dynamic Voltage restorer (DVR) device has been extensively utilized to keep the load voltage stable. To have a dynamic and fast response of the DVR a modified instantaneous reactive power (PQ) theory is proposed to control DVR under extreme transient voltage circumstances. The proposed technique is based on the extraction of the positive sequence component of grid voltage and the negative sequence component of load current for generating a voltage reference signal. The power system network with the proposed PQ control scheme is investigated and assessed under various scenarios to compensate for severe balanced, unbalanced (voltage sags and swells), and load change. MATLAB/Simulink is used to verify the mathematical models of the conventional PQ and proposed PQ control system for DVR. The complete system is implemented experimentally using a dSPACE 1104 based laboratory system to validate the presented control scheme. The simulation and experimental results are correlated, demonstrating the efficacy of the suggested modified PQ control technique.

The integration of photovoltaic (PV) systems with hydrogen production offers a sustainable method to utilize solar energy for the manufacturing of clean fuel. This paper examines recent breakthroughs in the integration of photovoltaic technology with water electrolysis, highlighting the technical feasibility and economic viability of these systems. Principal hydrogen production technologies, such as alkaline, proton exchange membrane (PEM), and solid oxide electrolyzers, are assessed regarding their compatibility with photovoltaic power outputs. Direct coupling solutions, including photovoltaic-electrochemical (PV-EC) systems, are emphasized for their capacity to optimize energy conversion processes. Notwithstanding the potential, obstacles such as the variability of solar irradiation, the responsive behavior of electrolyzers to changing power inputs, and the necessity for effective energy management systems remain. Recent research has illustrated kilowatt-scale solar hydrogen generation systems, with demonstrated production rates of up to 0.5–1.2 Nm³/h under peak irradiance, and overall solar-to-hydrogen efficiencies reaching 10˘18%. Levelized cost of hydrogen (LCOH) values from PV-powered systems currently range from 4 to 8 USD/kg H₂ , depending on the technology and location. Advancements in power electronics, particularly maximum power point tracking (MPPT) techniques, are essential for enhancing the efficiency of photovoltaic-powered electrolysis. The novelty of this study lies in its comprehensive and current synthesis of PV-electrolysis integration techniques, with a specific emphasis on direct coupling configurations, system scalability, and the enhancement of energy management through advanced MPPT techniques.It is essential to tackle these issues with creative system designs and control methodologies to facilitate the wider deployment of PV-hydrogen systems, thereby considerably aiding global decarbonization efforts.

Due to uncertain photovoltaic (PV) power generation, analyzing the voltage stability of transmission networks with a large PV plant is challenging. The stability of PV output power is a critical factor in establishing PV penetration levels in active transmission networks when assessing loading capabilities. Therefore, this article contributes to enhancing the understanding of how a static synchronous compensator (STATCOM) could be used as part of the power system network. STATCOMs are often used to improve the static and transient voltage, maintain transmission limits, and reduce low-frequency disturbances. With the help of a STATCOM unit, a proper investigation and analysis of dynamic voltage stability in a transmission system are presented. The validity of the study is evaluated by the Saudi Arabia grid code (SAGC). The system being tested is comprised of a 300 MW PV plant in Sakaka, Saudi Arabia, integrated into a 17-bus transmission power network and a STATCOM, which is employed at one of the buses. PSAT software is used to evaluate a number of case studies to determine the transient voltage stability with and without the STATCOM and the PV plant. The simulation findings demonstrate how STATCOM functions to improve the quality of the power system in accordance with the SAGC. In addition, the analysis of voltage stability demonstrates that the power network’s resilience to short circuits at the PV system’s grid connection point significantly impacts the voltage’s dynamic behavior.

The subject of power quality is gaining much interest nowadays. With the sophisticated sensitive electrical devices available in the market, power stations should ensure qualified and eminent power to the point of utilization. Bad voltage conditions in a power system can cause a malfunction at the point of utilization. Dynamic voltage restorer (DVR) is a reliable power electronic offsetting device which when engaged in the power system is effectual in the operation of compensating voltage sag/swell. In this research work, a DVR for offsetting multiple voltage disturbances in a power system is presented and a novel control strategy to trigger power switches in DVR is proposed. The proposed novel control methodology is compared with Synchronous Reference Frame (SRF) theory-controlled DVR. The simulation model is designed and the analysis with MATLAB/SIMULINK is presented