A Grid Connected Wind Energy System’s Power Quality Improvement By Using D-Statcom

Now a day’s one of the Main issue is Power Quality. The modern device performance is very sensitive with the power supply quality and makes it’s an important aspect. Power Quality problem occurs when the voltage, current and frequency become nonstandard and end use equipment gets damage. The harmonics, compensation of reactive power and power factor is a main problem dealt here. According to the guideline specified in International Electro-technical Commission standard, IEC-61400, by the measurements and norms specified can determine the performance there by power quality of a wind turbine. The active power, reactive power, voltage changes, flicker, harmonics, electrical behavior of switching operation are the concerning power quality measurements by the effect of the wind turbine in the grid system. These quantities are measured based on national/international guidelines. The power electronic switching devices such as Flexible AC Transmission System (FACTS) have been developed; introduction of customs power devices and the technology of emerging branch provide a modern control capability of power system. The paper study describes how the wind turbine installation creates power quality problem in grid system. In the proposed system in order to solve the power quality issues a battery energy storage system (BESS) connected by STATIC COMPENSATOR (STATCOM) at a common point coupling. The real power source under fluctuating wind power is sustained by the integrated   battery energy storage. For the power quality improvement of a grid connected wind energy generation system a STATCOM control scheme is simulated using MATLAB /SIMULINK in power system block set. Finally the proposed scheme is applied to a balanced linear load, unbalanced liner load, balanced non linear load and unbalanced non linear load

Power Quality Improvement and Low Voltage Ride through Capability in Hybrid Wind-PV Farms Grid-Connected Using Dynamic Voltage Restorer

© 2018 IEEE. Translations and content mining are permitted for academic research only. Personal use is also permitted, but republication/redistribution requires IEEE permission.This paper proposes the application of a dynamic voltage restorer (DVR) to enhance the power quality and improve the low voltage ride through (LVRT) capability of a three-phase medium-voltage network connected to a hybrid distribution generation system. In this system, the photovoltaic (PV) plant and the wind turbine generator (WTG) are connected to the same point of common coupling (PCC) with a sensitive load. The WTG consists of a DFIG generator connected to the network via a step-up transformer. The PV system is connected to the PCC via a two-stage energy conversion (dc-dc converter and dc-ac inverter). This topology allows, first, the extraction of maximum power based on the incremental inductance technique. Second, it allows the connection of the PV system to the public grid through a step-up transformer. In addition, the DVR based on fuzzy logic controller is connected to the same PCC. Different fault condition scenarios are tested for improving the efficiency and the quality of the power supply and compliance with the requirements of the LVRT grid code. The results of the LVRT capability, voltage stability, active power, reactive power, injected current, and dc link voltage, speed of turbine, and power factor at the PCC are presented with and without the contribution of the DVR system.Peer reviewe

Power Quality Improvement by Using Statcom Control Scheme in Wind Energy Generation Interface to Grid

“Electric Power Quality (EPQ) is a term that refers to maintaining the near sinusoidal waveform of power distribution bus voltages and currents at rated magnitude and frequency.” Today customers are more aware of the seriousness that the power quality possesses, this prompts the utilities to assure good quality of power to their customer. The power quality is basically customer-centric. The increased focus on utilities toward to maintaining reliable power supply by employing power quality improvement tools has reduced the power outages and blackout considerably. Good power quality is the characteristic of reliable power supply. Low power factor, harmonic pollution, load imbalance, fast voltage variations are some common parameters which are used to define the power quality. If the power quality issues are not checked, i.e., the parameters that define power quality doesn't fall within the predefined standards than it will lead to high electricity bill, high running cost in industries, malfunctioning of equipments, challenges in connecting renewables. Capacitor banks, FACTS devices, harmonic filters, SVC's, STATCOM are the solutions to achieve the power quality. The performance of Wind turbine generators is affected by poor quality power, at the same time these wind power generating plant affects the power quality negatively. This paper presents the STATCOM system with the BESS and studies the impact on the power quality in a system which consist of wind turbine generator, nonlinear load, hysteresis controller for controlling the operation of STATCOM and grid. The model is simulated in the MATLAB/Simulink. This scheme mitigates the power quality issues, improves voltage profile and also reduces harmonic distortion of the waveforms. BESS level out the imbalances caused by real power due to intermittent nature of wind power available due to varying wind speeds

Power Quality Improvement by Using Statcom Control Scheme in Wind Energy Generation Interface to Grid

“Electric Power Quality (EPQ) is a term that refers to maintaining the near sinusoidal waveform of power distribution bus voltages and currents at the rated magnitude and frequency.” The power quality is basically customer-centric. The increased focus on utilities toward maintaining reliable power supply by employing power quality improvement tools has reduced the power outages and blackout considerably. Good power quality is the characteristic of a reliable power supply. Low power factor, harmonic pollution, load imbalance, fast voltage variations are some common parameters which are used to define the power quality. If the power quality issues are not checked it will lead to a high electricity bill, the high running cost in industries, malfunctioning of equipment, challenges in connecting renewables. Capacitor banks, FACTS devices, harmonic filters, SVC’s, STATCOM are the solutions to achieve power quality. This paper presents the STATCOM system with the BESS and studies the impact on the power quality in a system which consists of the wind turbine generator, nonlinear load, hysteresis controller for controlling the operation of STATCOM and grid. The model is simulated in the MATLAB/Simulink. This scheme mitigates the power quality issues, improves voltage profile and also reduces harmonic distortion of the waveforms. BESS level out the imbalances caused by real power due to the intermittent nature of wind power available due to varying wind speeds

Fuzzy Logic Controller for grid connected Wind Energy Conversion System

The use of renewable power sources, like wind power, has been increased recently due to climatic changes caused by fossil fuels and fast depletion of fossil fuels. This has lead to the tremendous increase in the interconnection of wind turbines to power system grid. This interconnection on a large number in to grid causes problems such as power quality, maintaining system voltage, reactive power compensation, control of grid frequency and aspects of power system grid stability. In this proposed scheme, a fuzzy logic based controller is employed for a STATCOM to improve the power quality. The proposed control scheme supplies the required reactive power to the system and thus relieves the source, leading to Unity Power Factor (UPF) at the source and also it injects currents to reduce total harmonic distortion (THD) to satisfy IEC standard. For extracting the reference currents, an instantaneous reactive power theory based control algorithm is employed. To determine the effectiveness of the proposed fuzzy logic controller, a comparative analysis is also performed with a PI controller and the results have been presented

An Evaluation of Quality Improvement Methods Regarding Output Power of Wind Plants` Inverters

Today, with respect to the problems derived from non-renewable energy such as environment pollution, increasingly growth of fossil fuels` costs and the process of running out of sources; using renewable energies has been highly considered. Meanwhile, wind energy has widely been utilized. Integrating wind energy within power systems minimizes their effects on environment while connecting wind generation systems within power systems causes technical challenges such as the problems related to power quality, voltage regulation and sustainability where power quality is of highest importance. The present study attempts to evaluate the methods of improving inventers` quality in wind plants. To this purpose, “Space vector pulse width modulation”, “using STATCOM” and “using UPQS” to improve power quality are discussed

Offshore Wind Farm-Grid Integration: A Review on Infrastructure, Challenges, and Grid Solutions

Recently, the penetration of renewable energy sources (RESs) into electrical power systems is witnessing a large attention due to their inexhaustibility, environmental benefits, storage capabilities, lower maintenance and stronger economy, etc. Among these RESs, offshore wind power plants (OWPP) are ones of the most widespread power plants that have emerged with regard to being competitive with other energy technologies. However, the application of power electronic converters (PECs), offshore transmission lines and large substation transformers result in considerable power quality (PQ) issues in grid connected OWPP. Moreover, due to the installation of filters for each OWPP, some other challenges such as voltage and frequency stability arise. In this regard, various customs power devices along with integration control methodologies have been implemented to deal with stated issues. Furthermore, for a smooth and reliable operation of the system, each country established various grid codes. Although various mitigation schemes and related standards for OWPP are documented separately, a comprehensive review covering these aspects has not yet addressed in the literature. The objective of this study is to compare and relate prior as well as latest developments on PQ and stability challenges and their solutions. Low voltage ride through (LVRT) schemes and associated grid codes prevalent for the interconnection of OWPP based power grid have been deliberated. In addition, various PQ issues and mitigation options such as FACTS based filters, DFIG based adaptive and conventional control algorithms, ESS based methods and LVRT requirements have been summarized and compared. Finally, recommendations and future trends for PQ improvement are highlighted at the end

Impact of the Integration of a STATCOM Controlled by LQG/H2 Regulator in an Energy System

© The Author(s); licensee IIETA, Edmonton, Canada. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/Nowadays, the reactive power consumption is becoming a serious problem for electricity network management. To overcome this problem, several solutions are proposed in the literature. In the present study, the static reactive power compensator (STATCOM) solution is used to keep the network voltage within its rated range. The STATCOM is modeled in the axes of Park reference frame and is driven controlled by a SVPWM strategy. Its control scheme is based on a multivariable Linear Quadratic Gaussian (LQG/H2) controller, which has the advantage of being applied to systems whose condition is not measured. Simulations are performed using the MATLAB/SIMULINK software. Results are presented, compared and discussed.Peer reviewe