Power Quality Conditioner System Research Articles

Advanced Universal Power Quality Conditioning Systems for Stabilizing Micro-Grid’s Frequency

This paper proposes a new unified active filter to alleviate instantaneous unwanted oscillating powers as they may lead to frequency variations in weak systems. First, the paper presents negative impacts of capacitive loads on the shunt active power filter performance in compensation of instantaneous oscillating real power. Secondly, an advanced universal power quality conditioning system (AUPQS) for three-phase/four-wire systems under non-ideal waveforms is introduced. By considering the suggested compensation algorithm, the AUPQS is able to extremely suppress instantaneous oscillating powers caused by distorted-unbalanced load-terminal voltages. Moreover, an independent single-phase converter is suggested at the load-end in order to regulate the DC-link voltage. Therefore, the instantaneous oscillating powers perfectly suppress and thus, the source-end three-phase currents will be purely sinusoidal. The suggested AUPQS is used to stabilize micro grid frequency. The effectiveness and flexibility of the proposed AUPQS are confirmed by Matlab/ Simulink simulations.

Power Quality Improvement in Multifeeder Using MC-UPQC

Power Quality (PQ) issues have been a major concern as there is increased load demand and usage of variety of nonlinear loads. The innovation of Flexible AC Transmission System (FACTS) devices is a great way of solving PQ issues. Many devices like UPFC, D-STATCOM, and TCPST are emerging and are widely used for PQ improvement. In this paper, the Multi Converter Unified Power Quality Conditioning (MC-UPQC) System will be used for improving PQ in multi-bus systems. The system of MC-UPQC contains one shunt and two series Voltage Source Converter (VSCs). The conventional methodology contains one shunt and one series static devices. In the proposed methodology, two series VSCs will be used for further reduction of overall THD value. The simulation results of a reduction in THD and an improvement in PQ are compared with and without the proposed using MATLAB. Keywords—PQ, MC-UPQC, series VSC, shunt VSC, MATLAB.

Performance Analysis of Universal Power Quality Conditioner Systems Based on Seven-level NPC Inverter Using PD-SPWM with Fuzzy Control Scheme

This paper presents novel Unified Power Quality Conditioner (UPQC) system based on seven-level Neutral Point Clamped (NPC) inverter using combined PD-SPWM and fuzzy control scheme. The proposed UPQC is adopted to mitigate source current harmonics and compensate all voltage disturbances simultaneously. It is designed by the combination of series and shunt Active Filters (AFs) connected by a common DC link capacitor. The DC voltage at common DC bus is maintained constant using proportional integral voltage controller. The Synchronous Reference Frame (SRF) method is used to get the shunt APF reference signals and the power reactive theory (P-Q theory) for the series APF. Conventional control schemes require complex calculations, the use of intelligent systems help to reduce the control system size and the operation complexity. The shunt and series Active Power Filter (APF) reference signals derived from the control algorithm are injected in Fuzzy intelligent controllers to generate switching signals. The functionality of proposed UPQC system and its control system is evaluated using Matlab-Simulink software and SimPowerSystem Toolbox under various operation conditions in cases of most common power quality problems such as voltage sag, voltage swell, current harmonic compensation of nonlinear loads and unbalanced load. The simulation results show UPQC performances to improve the power quality in steady and transient conditions operation at the point of common coupling on power distribution under unbalanced and distorted voltage conditions.

Design Simulation of Improved Power Quality Conditioner System for Enhancement of Power Quality

The increased usage of power-sensitive electronic devices has prompted interest in power conditioning solutions, which is no surprise. As a result, some type of compensation must be supplied if power output remains below the standards' prescribed limitations. The UPQC (Unified Power Quality Controller) is one of numerous AC Transmission System families that can control voltage, impedance, and phase angle among other factors (FACTS). This study focuses on modern UPFC systems that have increased power quality efficiency to help utilities reduce voltage concerns. One of the FACTS controls for lowering stress sales effects is a unified power quality conditioner (UPQC). The quadrature voltage is specified using the UPQC series compensator. As a result, the compensator series never utilizes active power in a continuous scenario. As mentioned in the approach, a low power rating compensator injects voltage to remedy the system's power quality problem. The voltage is decreased and the power factor is raised when the fluid logic controller is used in conjunction with traditional UPQC. Furthermore, the load factor has been improved. The circuit is then imitated in MATLAB / SIMULINK using a fluctuating logo controller.

Artificial Neural Network based Solar Energy Integrated Unified Power Quality Conditioner

ABSTRACT The utility grid is prone to power quality issues due to the advent of power electronic devices and integration of Distributed Energy Resources. The power quality has to be maintained despite variation in load under steady and fault conditions. Unified Power Quality Conditioner is a FACTS device that improves the power quality at the Distribution side of the utility grid. In Unified Power Quality Conditioner, reactive and real power compensation is carried out simultaneously improving the power quality. The proposed control algorithm for Unified Power Quality Conditioner is a hybrid combination of Reactive Power Control and Unit Vector Template. The Unified Power Quality Conditioner is integrated with Distributed Energy Resources like solar energy to minimize the power rating of converters and meet the power demand. The reinforced learning algorithms have been effectively increasing the performance of the power electronic devices; among them, the most commonly used is the Neural-Network algorithm. The Artificial Neural Network controller for the solar integrated Unified Power Quality Conditioner system improves the power quality when compared to the conventional controllers by self-adapting themselves to the environmental needs. The system is tested under both balanced and unbalanced load conditions with MATLAB-SIMULINK. The per-unit system has been used for the analysis purpose to minimize the complexity. The hybrid control of the series and shunt converters supported by solar integration at the DC link proves to eliminate distortion caused by the non-linear load. The system is subjected to a momentary voltage sag/swell as per IEEE 1159 standards. The momentary sag/swell that varies between 0.5 seconds to 3 seconds has been made to ride through less than 50 milliseconds as per the Computer and Business Equipment Manufacture Association curve. The load side current harmonics have been minimized inevitably by the proposed control methodology to ensure reliability and good power factor at the Distribution side. A comparative analysis between the conventional Proportional-Integral controller and Artificial Neural Network controller in solar integrated Unified Power Quality Conditioner proved the Artificial Neural Network controller improved the harmonic reduction of various orders by an average of 12.72%. The Total Harmonic Distortion minimization for various harmonic orders was brought under the limits of IEEE 519 standards with Artificial Neural Network controller.

Grid integration of Photovoltaic System Interfaced with Artificial Intelligence based Modified Universal Power Quality conditioning system

Unified Power Quality Compensators (UPQC) in load side utility system is not able to fully suppress harmonies in power grid and distortion in the interface system. To enhance the operation of the UPQC, a Fuzzy based Modified Universal power quality conditioning system (Fuzzy-MUPQCS) is developed. Modified Universal power quality conditioning system (MUPQCS) is a combination of two active filters in series and one active filter in shunt. A 3φ voltage source inverter is also used to maintain a common DC link capacitor voltage through Photo voltaic (PV) system connected to a utility grid. Highest Power Point Tracking (HPPT) algorithm is mainly used to pull out the maximum amount of power in the PV system. In this paper, Proportional integral controller based MUPQCS (PI- MUPQCS) and Fuzzy-MUPQCS are used to analyse the load voltage and load current distortion, THD analysis, power factor measurement, grid voltage and grid current distortion in the three phase system under nonlinear load conditions. The execution of the MUPQCS based 3φ system and the controllers are simulated using Matlab /Simulink model.

Distributed Power Quality Conditioning System for Three-Phase Four-Wire Low Voltage Networks

This paper presents distributed power quality conditioning system to compensate current and voltage distortions in three-phase four-wire networks caused by unbalanced non-linear single-phase loads. The proposed conditioning system consists of several hybrid filter units installed in various nodes for compensation of excessive neutral currents and voltage distortions in a selected area of the distribution network. The system is open and it can be easily modified by installation of new filter units. A novel hybrid filter design procedure based on filter frequency characteristics optimization in the parameters of passive and active parts is presented. A digital system of control signal computation for active filters based on the use of modern methods of spectral analysis is considered. The proposed digital control system enables selective compensation of fundamental and harmonic components. The mathematical model of the proposed power quality conditioning system is developed in the MatLab software. The simulated results show that the presented conditioning system reduces the level of neutral conductor currents and the voltage unbalance as well ensures harmonic compensation in three-phase four-wire networks.

Fractional-Order PID Controlled Unified Power Quality Conditioner System with Enhanced Response

Recently, ‘UPQC’ has been urbanized as a FACTS controller near weak buses and buses with non linear loads. ‘UPQC’ can improve receiving end voltage and provide time harmonics to the load. The UPFC and ‘UPQC’ systems are compared to find a better FACTS controller. The recommended closed loop ‘UPQC’ framework is to augment dynamic response of ‘UPQC’ system using FOPID controller. Simulink replicas are extended for PI &FOPID controlled ‘UPQC’ frameworks. The denouements of PI&FOPID based ‘UPQC’ frameworks designate that voltage retaliation of FOPID is predominant to the denouement of PI managed ‘UPQC’ system. The investigation denotes that FOPID ’UPQC’ framework has diminished settling time& steady state error.

Design and Simulation of a Unified Power Quality Conditioner by Fuzzy Logic for Egyptian Power Grid Connected to Zafarana Egypt Wind System

Wind energy system is lately receiving a lot of attention, because they are cost inexpensive, environmental safe and clean renewable energy source, as compared with nuclear and fossil fuel power generation. The operational characteristics of wind electric turbines has considerable dissatisfaction and stress on the quality of electric power system. Harmonics, variations of voltage and reactive power are most of power quality issues for grid connected with wind turbine. This paper introduces a design and simulation of unified power quality conditioner using a fuzzy controller to improve the power quality for Egyptian power grid connected to Zafarana Egypt wind system. The proposed performance of the unified power quality conditioner system is verified by simulating the model using MATLAB/SIMULINK environment. The simulation results showed that the proposed unified power quality conditioner provide efficient cancellation of both load current harmonics and supply voltage sag in addition to compensation of reactive power, and thus making the electrical grid connected wind energy system more efficient by improving the quality of power.

Design and Simulation of a Unified Power Quality Conditioner by Fuzzy Logic for Egyptian Power Grid Connected to Zafarana Egypt Wind System

Wind energy system is lately receiving a lot of attention, because they are cost inexpensive, environmental safe and clean renewable energy source, as compared with nuclear and fossil fuel power generation. The operational characteristics of wind electric turbines has considerable dissatisfaction and stress on the quality of electric power system. Harmonics, variations of voltage and reactive power are most of power quality issues for grid connected with wind turbine. This paper introduces a design and simulation of unified power quality conditioner using a fuzzy controller to improve the power quality for Egyptian power grid connected to Zafarana Egypt wind system. The proposed performance of the unified power quality conditioner system is verified by simulating the model using MATLAB/SIMULINK environment. The simulation results showed that the proposed unified power quality conditioner provide efficient cancellation of both load current harmonics and supply voltage sag in addition to compensation of reactive power, and thus making the electrical grid connected wind energy system more efficient by improving the quality of power.

Performance Enhancement of PV-Fed Unified Power Quality Conditioner for Power Quality Improvement Using JAYA Optimized Control Philosophy

In this paper, the operation and control of photovoltaic-fed unified power quality conditioner in grid-connected mode including the power quality enhancement feature has been systematically examined. The current harmonics, voltage sags, voltage swells, voltage unbalance, dc-link voltage regulation are the primary factors limiting the performance of the AC system. Therefore, these power quality issues are needed to be eliminated by high-performance power conditioners controlled through highly effective control strategies. In this paper, an optimization algorithm is used to amplify the controller performance by achieving the best numerical parameters for proportional plus integral controller of PV-UPQC. Detail analysis involving elimination of current harmonics, voltage sags and voltage swells are investigated to analyze the effect of novel optimization algorithm on controller of photovoltaic-fed unified power quality conditioner system. In addition, this paper proposes double second-order integral quadrature signal generator-based phase-locked loop mechanism for proper grid synchronization. Finally, experimental verification of the performance of the proposed scheme by hardware prototype development has been included.

An Advanced Universal Power Quality Conditioning System and MPPT method for grid integration of photovoltaic systems

A photovoltaic system usually produces power quality pollutions to the interfaced power systems without a proper functioning of active filters. At present, available active filters are unable to fully suppress power grid harmonics and distortions, worsening power quality conditions within the interfaced system. This paper presents an Advanced Universal Power Quality Conditioning System (AUPQS) to interface photovoltaic systems to a power grid. In the interfaced system, an improved series active filter is designed to generate output voltages to compensate all the source voltage deficiencies and to highly suppress the grid-end current harmonics and distortions, even under unbalanced non-linear load conditions. Also, an independent single-phase inverter is suggested at the load side instead of the source side to regulate the DC-link voltage. Hence, the distortions and harmonics generated by this single-phase inverter are absorbed by the shunt filter of the AUPQS. Finally, a hybrid maximum power point tracking (MPPT) approach is proposed for effective operation of photovoltaic systems even under sudden light intensity changes and solar cells temperature variations. The overall interfaced system is designed and developed using Matlab/Simulink software. The effectiveness of the proposed AUPQS and MPPT method is further validated by simulation results.

A Novel Unified Power Quality Conditioning System for Power Quality Improvement and Bidirectional Power Flow Control for Windmill

A Novel Unified Power Quality Conditioning System for Power Quality Improvement and Bidirectional Power Flow Control for Windmill

Reciprocal effects of the distorted wind turbine source and the shunt active power filter: full compensation of unbalance and harmonics under ‘capacitive non‐linear load’ condition

Available compensating algorithms for shunt active power filters (SAPFs) and unified power quality conditioner perform somehow improperly in practice under certain circumstances. Typical examples could be any distorted `non-linear loads' showing low impedances at certain frequencies; also, there are technological limitations for the SAPF in modulating switching frequencies, including microcontroller processing speed, the employed control and modulation techniques, delays and so on. This study proposes an advanced universal power quality conditioning system (AUPQS) to fine tune the available solutions for generating purely sinusoidal wind turbine-end currents under both distorted-unbalanced load-terminal voltages and non-linear load conditions (capacitive loads leave much worse consequences than those of the inductive). It is shown that both series and SAPF are capable of full compensation of microgrid by the SAPF using the advanced generalised theory of instantaneous power. Meanwhile, the resultant source currents could be somehow non-sinusoidal. However, the proposed AUPQS will be able to fully eliminate the consequence of voltage asymmetry and unbalanced waveforms on the SAPF, generated because of the wind turbine operation by performing certain corrections on these solutions. Moreover, an independent single-phase rectifier is proposed at the load-end to regulate DC-link voltage. Effectiveness of the proposed AUPQS is confirmed by Simulink simulations.

Power Quality Problems Compensation With Universal Power Quality Conditioning System

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> The aim of this paper is to present a universal power quality conditioning system (UPQS) named after unified power quality conditioner, which is extended by adding a shunt active filter at the load side. Its main purpose is to compensate for both supply voltage and load current imperfections, such as: sags, swells, interruptions, imbalance, flicker, harmonics, reactive currents and current unbalance. Such system has better harmonic compensation characteristic, since there are no problems associated with passive filter operation. Converter and control analysis is presented, together with results showing the UPQS modes of operation. </para>

Power quality compensation using universal power quality conditioning system

The aim of this letter is to present a universal power quality conditioning system (UPQS) named after a unified power quality conditioner (UPQC), which is extended by adding a shunt active filter at the load side. Its main purpose is to compensate for supply voltage and load current imperfections, such as sags, swells, interruptions, imbalance, flicker, harmonics, reactive currents, and current unbalance. Converter and control analysis is presented together with results showing the UPQS modes of operation.