Several advantages make wind-driven permanent magnet synchronous generators (PMSGs) very promising in the wind energy market, especially their fault ride-through capabilities. With the high penetration levels of today, both the grid and wind power (WP) systems are being affected by each other. Due to grid faults, the DC-bus in PMSG systems typically experiences overvoltage, which can negatively affect the generator parameters and trip the system. However, advancements in power electronics, control systems, fault limiters, FACTS, and energy storage technology make it possible to find and design satisfactory solutions and approaches. The most recent FRTC-improving techniques are mainly modified or external techniques based on controllers in PMSG-based WP. This paper evaluates the in-depth schemes of FRTC, introducing the underlying theory and traits of the different approaches to highlight the advantages and drawbacks of each. Five scenarios of DC-link voltage under zero-grid voltage are carried out by using the MATLAB SIMULINK program to assess the FRTC methods. This study shows that external device-based approaches can be efficient, but some of them are expensive, thus updated controller methods are recommended to cut costs. Research findings of this study are expected to support the deployment of FRTC technologies, as well as provide valuable input into WP research on grid integration.

In recent modern power systems, the number of renewable energy systems (RESs) and nonlinear loads have become more prevalent. When these systems are connected to the electricity grid, they may face new difficulties and issues such as harmonics and non-standard voltage. The proposed study suggests the application of a whale optimization algorithm (WOA) based on a fractional-order proportional-integral controller (FOPIC) for unified power quality conditioner (UPQC) and STATCOM tools. These operate best with the help of their improved control system, to increase the system’s reliability and fast dynamic response, and to decrease the total harmonic distortion (THD) for enhancing the power quality (PQ). In this article, three different configurations are studied and assessed, namely: (C1) WOA-based FOPIC for UPQC, (C2) WOA-based FOPIC for STATCOM, and (C3) system without FACTS, i.e., base case, to mitigate the mentioned drawbacks. C3 is also considered as a base case to highlight the main benefits of C1 and C2 in improving the PQ by reducing the %THD of the voltage and current system and improving the systems’ voltage waveforms. With C2, voltage fluctuation is decreased by 98%, but it nearly disappears in C1 during normal conditions. Additionally, during the fault period, voltage distortion is reduced by 95% and 100% with C2 and C1, respectively. Furthermore, when comparing C1 to C2 and C3 under regular conditions, the percentage reduction in THD is remarkable. In addition, C1 eliminates the need for voltage sag, and harmonic and current harmonic detectors, and it helps to streamline the control approach and boost control precision. The modeling and simulation of the prepared system are performed by MATLAB/Simulink. Finally, it can be concluded that the acquired results are very interesting and helpful in the recovery to the steady state of wind systems and nonlinear loads, thereby increasing their grid connection capabilities.

The voltage quality (VQ) index has become a significant measure of recent power system stability. The integration of photovoltaic (PV) systems plus smart home loads (SHLs) at low voltage levels (LVLs) has resulted in various issues such as harmonics rise and voltage instabilities as a result of faults and systems nonlinearity. In this work, a dynamic voltage resistor (DVR) is implemented to enhance VQ, and its dynamic performance hinges on its control system ability. To enhance the DVR’s control system, for surpassing nonstandard voltage with a quick response and harmonics reduction at LVL under harsh operating events, an optimal controller design using the Harris Hawks algorithm (HHA) is proposed. To verify the value of the suggested solution, the hard operating events (voltage sag, voltage swell, fluctuating voltage, and imbalanced voltage) are examined and assessed. To show the effectiveness of the HHA technique, a comparison of the % total harmonic distortion (THD) reductions achieved by the suggested and conventional controllers of DVR is conducted for the scenarios under study. Moreover, the suggested controller stability is analyzed and assessed using Lyapunov’s function. The benefits of the optimized controller system are inferred from the results, including their robustness, simplicity, efficient harmonic rejection, minimal tracking error, quick response, and sinusoidal reference track. The results of the simulation show that the DVR’s optimized controller is efficient and effective in maintaining a voltage at the needed level with low THD, safeguarding the sensitive load as expected, and showing a noticeable improvement in voltage waveforms. The mathematical modeling of HHA, PV system, DVR, and SHLs are all verified using MATLAB\Simulink.

Power quality (PQ) assurance is a vital part of electrical distribution networks. There are many advantages and benefits of improving PQ, especially in the modern/smart grid. Smart grid (SG) has a lot of complicated and sensitive electrical components (non-linear loads) in addition to renewable energy systems (wind-solar) that may also be a source of PQ disturbances. PQ problems harm personal life and national production. Static synchronous compensator (STATCOM) and unified power quality conditioner (UPQC) are among the fastest response flexible alternating current transmission systems (FACTS) installed in smart grids to mitigate power quality disturbances such as voltage fluctuations, sag, swell, and harmonics. In this research, STATCOM and UPQC are designed and simulated in MATLAB/Simulink to overcome PQ-related disruptions in smart grids. Accordingly, the differences between the proposed two solutions are highlighted across this research and renewable energy sources' reliability during faults. Therefore, the reader will be able to choose the appropriate FACTS devices. This study emphasizes the extent of the smart grid need for the FACTS. As per the given results of this study, STATCOM and UPQC have shown exemplary performance in the PQ improvement investigations conducted in the context of smart/modern grids.

Electrical power quality is becoming intensity concerned from both electric utilities and customers. Voltage fluctuation is a major power quality problem as it has a significant impact on both the equipment and production environment. This work describes the voltage control technique of mitigation of voltage fluctuations and clearing fault using distribution static synchronous compensator (DSTATCOM).The test system used is Egyptian native power distribution system. A simulation was done using MATLAB/Simulink software.

The smart grid (SG) is a new scientific progress concept. Residential and commercial colonies and smart homes have many sensitive electrical devices and renewable energy systems (solar and wind). SG is greatly affected by Power Quality (PQ) disturbances. PQ has significant impacts on the low voltage smart grid, such as flicker, voltage sag/swell, and harmonics, causing substantial losses and disrupting the SG system. The smart home resident needs a clean and reliable electric power energy source without any PQ troubles. Dynamic Voltage Restorer (DVR) is a costefficient and promising static var device installed in series with transmission and distribution lines to protect PQ disturbances in electrical power systems. This research introduces an idea to improve PQ disturbances in the smart distribution grid (smart home) at the low voltage side using a Low-Cost Two-level inverter DVR. This study will use a two-level inverter topology to integrate with the DVR System to obtain a simple and straightforward Low-Cost Two-level Inverter DVR approach that is easy to use, flexible, and practical. In this research, the proposed DVR was designed and simulated in MATLAB/Simulink, where it shows excellent performance to overcome PQ-related disturbances such as voltage sag/swell, flicker, and harmonics with percentages close to 99%.

<em><span>Power Quality is becoming intensity concerned from both electric utilities and customers. Voltage Flicker is a major power quality problem as it has a significant impact on both the equipment and production environment. This work describes the voltage control technique of reduction of voltage flicker and clearing fault using Distribution Static Synchronous Compensator (DSTATCOM). The test system used is IEEE 9-bus distribution system clarified the optimal location of DSTATCOM by using Artificial Neural Network. A simulation was done using MATLAB/Simulink software.</span></em>