Shunt Active Filter Research Articles

MITIGATION OF VOLTAGE SAGS AND STABILITY ANALYSIS OF DISTRIBUTION SYSTEM BASED ON UPQC USING SUBSTANTIAL TRANSFORMATION INTRINSIC ALGORITHM (STIA)

The quality of power is important one of the distribution system, and it identify the voltage and current based distribution system power quality problem. The Voltage sag and swell is also to create power quality problem. In this power quality problem creates the frequency oscillation in the distribution system, so the output stability is affected. Because of this limitation, design of these improved model of controlling are properly required. The UPQC (Unified Power Quality Conditioner) is utilized to compensate the power quality problem and reduce the unbalanced voltage of this system. The proposed Substantial Transformation Intrinsic Algorithm (STIA) based UPQC is used to analysis the unbalanced voltage of this power distribution system. This proposed UPQC system is inject the real power to the transmission line, so the unbalanced voltage is compensate. Such that the injected voltage is controlled with help of series nd shunt active filter, and the angle of voltage injection is also controlled. The proposed STIA technique is used to give the proper pulse of this shunt and series converter to optimize the power quality problem with help of injecting the real power in this transmission line. The proposed Substantial Transformation Intrinsic Algorithm (STIA) method has run through the SIMULINK model, and this system attain the good performance, reduce the losses and increase the stability of power transmission line.

Harmonic Reduction Using Shunt Active Filter for Electrical Installation

This paper presents harmonic reduction using an active shunt filter for hospital building electrical installation. Generally, harmonic installation in electric power systems is caused by non-linear electrical loads, especially the ones containing coils, such as air conditioners, pump machines, fans, and others. It might cause excessive heat in a distribution transformer which supplies an electrical installation in a multi-story building. In this regard, the heat is a power loss and has the potential to shorten the life of a distribution transformer, and therefore, efforts are needed to reduce harmonics. The use of active filters is one of the most effective strategies for reducing harmonics. In this study, a shunt active filter application in the electrical installation of a hospital building was carried out. The results showed the filter reduced harmonic currents significantly, to the extent that the harmonic threshold was still under the IEEE standard.

Single-phase thirteen-level dual-boost inverter based shunt active power filter control using resonant and fuzzy logic controllers

This paper address the power quality improvement of a single-phase utility grid using Thirteen-Level Dual-Boost Inverter (TLDBI) — Shunt Active Filter (SAF). The TLDBI uses a single DC source of low voltage magnitude and five switched capacitor arrangement to achieve self-balanced thirteen level output voltages. Moreover, the charging and voltage balancing of capacitor is achieved by proper switching sequence control in a series, through which boosted inverter output voltage levels are obtained. Compare with the tradional H-bridge Multilevel inverters (MLIs), all the elements in the proposed TLDBI are able to withstand a voltage stress which is equal to the input dc source. This feature ensures the performance of the proposed TLDBI in high-frequency applications. The power at the electrical grid is highly affected by wide range of non-linear loads. The proposed SAF is used to measuring and controlling the current flow from source to load. The difference between the targeted and actual currents from the utility grid is measured by using the modified Synchronous Reference Frame (SRF) theory. The estimated error current is used by the controllers to predict the optimum suitable switching angle and Modulation Index (MI) to the TLDBI-SAF. In this work, the traditional Proportional-Integral (PI) controller, Fuzzy Logic Controller (FLC) and Proportional Resonant Controller (PRC) are compared and the results are presented to validate the performance of SAF. The stability and robustness of the proposed controller is evaluated using Bode, Root locus, and Nyquist plots. The modeling and analysis of the proposed system are done using MATLAB/Simulink environments. The simulation results are presented in the various MI of TLDBI and also subjected to non-linear load conditions. The results are also compared to the claim novelty of the proposed work.

PSO-GWO Optimized Fractional Order PID Based Hybrid Shunt Active Power Filter for Power Quality Improvements

This paper presents a Hybrid Shunt Active Power Filter (HSAPF) optimized by hybrid Particle Swarm Optimization-Grey Wolf Optimization (PSO-GWO) and Fractional Order Proportional-Integral-Derivative Controller (FOPIDC) for reactive power and harmonic compensation under balance and unbalance loading conditions. Here, the parameters of FOPID controller are tuned by PSO-GWO technique to mitigate the harmonics. Comparing Passive with Active Filters, the former is tested to be bulky and design is complex and the later is not cost effective for high rating. Hence, a hybrid structure of shunt active and passive filter is designed using MATLAB/Simulink and in real time experimental set up. The compensation process for shunt active filter is different from predictable methods such as (p-q) or (i d -i q ) theory, in which only the source current is to be sensed. The performance of the proposed controller is tested under different operating conditions such as steady and transient states and indices like Total Harmonic Distortion (THD), Input Power Factor (IPF), Real Power (P) and Reactive Power (Q) are estimated and compared with that of other controllers. The parameters of FOPIDC and Conventional PID Controller (CPIDC) are optimized by the techniques such as PSO, GWO and hybrid PSO-GWO. The comparative simulation/experiment results reflect the better performance of PSO-GWO optimized FOPIDC based HSAPF with respect to PSO/GWO optimized FOPIDC/CPIDC based HSAPF under different operating conditions.

Performance Investigation of Grid-Connected DFIG using Integrated Shunt Active Filtering Capabilities

This paper presents the modified grid side converter control (GSC) technique which enable the GSC to work as a shunt active filter to mitigate the grid current harmonics produced by the nonlinear load, as well as to transfer power from the grid to the rotor of doubly fed induction generator (DFIG) or vice versa. The main contribution of this proposed technique is an addition of a shunt active filter with space vector pulse width modulation (SVPWM) controller in GSC control itself in order to achieve a better grid current %THD profile, and simultaneously to control active power for variable wind speed. The reactive power supply to the DFIG and extraction of maximum power is achieved using RSC. The comparison of the modified GSC control technique using hysteresis current control (HCC), and SVPWM controller used to mitigate the harmonics is presented with different wind speeds. The proposed modified GSC control technique is simulated for grid-connected 2.6 MW DFIG based wind energy conversion system (WECS) in MATLAB Simulink environment.

Active filtration theory of multiphase power supply sys tems aimed at minimizing the power loss in the transmission line

The active filtration theory of multiphase power supply systems aimed at minimizing the power losses in the transmission line has been further developed. New relations are substantiated, and a new physical content is given for the instantaneous active current and the instantaneous apparent power, which take into account the dependence of the transmission line resistance ratio and correspond to similar integrated values of the periodic mode of a multiphase power supply system. It is shown that the instantaneous and integral values of the minimum possible losses are proportional to the square of the load power and inversely proportional to the short-circuit power. These values can be used to determine the power factors of a given load and gain coefficients for power losses. The calculated ratios for the gain coefficients for the instantaneous and integral power losses when using a shunt active filter with control strategies that form in the transmission line vectors of the active current according to the proposed formulas were obtained. The results of computer simulation confirmed the adequacy of all modified relations for the basic concepts of the active filtration theory of multiphase power supply systems and the advantages of the proposed active filtration strategies.

Power Quality Improvement in 3-Phase Power System Using Artificial Neural Network Based Hybrid Filter

Harmonic-distortion is a serious problem in power systems involving linear and non-linear loads. Adding a passive-filter to the system is the most popular choice to reduce issues due to harmonic distortion. Passive-filter cannot eliminate all the harmonic components. A hybrid-filter, in which shunt active filter is serially integrated with shunt passive filter can provide better solution to the problems causing due to harmonic distortions. The paper proposes a hybrid filter with Artificial Neural Network (ANN) based control scheme. A detailed study is done by developing a Simulink model for the proposed. Here in this paper, % Total-Harmonic-Distortion (THD) of compensated load-current is referred as a performance measure of the system. Also, a controller based on ANN is fabricated for the proposed scheme and through analysis in depth is carried out, this controller performance is found comparatively satisfactory.

Binary Hybrid Multilevel Inverter-Based Grid Integrated Solar Energy Conversion System With Damped SOGI Control

This paper presents a binary hybrid multilevel inverter (BHMLI) based grid-connected solar energy conversion system (SECS), controlled by damped second-order generalized integral (DSOGI). The BHMLI architect has a cascaded half-bridge array, which modifies the DC-link of the H-bridge of the voltage source inverter, and results in approximate reference waveform. It reduces the dV/dt of the H-bridge switches and improves output waveform quality. The DSOGI control damps the oscillations and overshoots and provides longer service period of low power switches at transient conditions. It is implemented in the multilevel inverter application for the first time in literature. The SECS is designed to inject active power to the grid, and also mitigates the harmonic and reactive power demands of the load. The cascading of n' half-bridges and one H-bridge generate (2 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">(nC1)</sup> - 1) output voltage levels. The maximum power extraction from solar photovoltaic (PV) array is achieved through incremental conductance (IC) algorithm based maximum point tracking (MPPT) operation of the DC-DC converter. An isolated single-input multiple-output single-ended primary inductance converter (SIMO-SEPIC) realizes it. SECS with 15-level BHMLI is analyzed with extensive simulation as well as with a hardware prototype. Moreover, the shunt active filter functionality of the system at various load conditions are verified and maintained the grid power quality within the IEEE-519 standard throughout the operation. The laboratory developed setup is tested for 5 kW, 400 V, three-phase system, and the experimental analysis at steady-state and dynamic variations of load-side and insolation variations validate the theoretical claims.

PV Based Grid System for Power Quality Enhancement using Instantaneous P-Q Theory

The SPV interfaced grid system with battery storage unit, bidirectional VSI interconnected shunt active filter, an adaptive Proportional Integral (PI) controller is employed for improve current and voltage profile enhancement. The p-q theory is the common employed technique to extract the basic fundamental current harmonic components from affected or polluted power supply by means of diode rectifier or non linear load. The basic concepts of reactive power (IRP) theory includes it’s a time domain model and it can be applicable for both 3P3W and 3P4W. Initially, the control technique called instantaneous real and reactive power theory or p-q theory has been developed for three phase three wire system and then later it was extend to three phase four wire system. This system is valid under steady state as well as dynamic state. The bidirectional VSI based shunt APF is controlled by the PI based instantaneous reactive power theory. The proposed PI Controller interfaced shunt Active Power Filter is used to maintain DC-Link voltage.SPV system is interfaced with incremental conductance MPPT algorithm. This SAPF control scheme has to provide the following benefits like current harmonic mitigation as well as reactive power compensation

Modelling and Analysis of PV-Based Shunt Active Filter with BESS and Conservative Power Theory for Enhancing Power Quality

Abstract Power Quality has always been a major concern ever since the increase in the usage of many power electronic loads such as Personal Computers (PCs), TVs, variable frequency drives in nearly every household. These loads are a major source of harmonics into the distribution system. Unbalanced Three-phase loads or different single-phase loads result in unbalance in the three-phase voltages and currents in the grid. Equipment damage, Loss of data, nuisance tripping, overheating of wires, relay tripping are few of the major issues caused due to power quality. Also, there is an increase in the awareness about the various power quality issues as well as its ill-effects amongst the consumers. Hence, it is essential to improve the quality of the power supplied. Active and Passive filters play a huge role in the mitigation of power quality issues. In recent years, usage of active filters has increased because tuning is possible for various harmonic elimination and active filters when combined with a storage system can provide active as well as reactive power compensation. The fast depletion of non-renewable sources of energy and its effect on the environment has shifted the focus on the usage of non-renewable energy sources such as solar energy, wind energy, etc for the production of electricity. In this research work, solar energy is combined with shunt active filter for the mitigation of various power quality issues occurring in a grid-connected non-linear and unbalanced three-phase load. The active power filter will provide reactive power compensation to the non-linear load and active power delivery for unbalanced loads such the grid current and voltage will remain balanced and the stress on the grid is reduced while meeting the load demand. A battery system is also integrated to store the excess energy that may be generated by the Photo-Voltaic(PV) array and acts as a source of energy when PV array output is low or nil. Conservative Power Theory is used for controlling the power injection into the system by the Voltage Source Converter(VSC). The proposed system is verified using MATLAB/SIMULINK.

A shunt active filter for compensating harmonics and unbalance in three-phase four-wire systems

ABSTRACT This paper introduces a split-capacitor shunt Active Power Filter (SC-APF) based on Synchronous Reference Frame (SRF) theory. This topology is used in compensating the currents of 3-Ph unbalanced non-linear loads. The voltage control loop used in SRF which is only suitable in controlling Four-Leg APF (FL-APF) is modified to control Spilt-Capacitor APF (SC-APF). The proposed scheme provides compensating the 3-Ph unbalanced non-linear loads with lower number of switches, passive elements, and sensors. The performance of the SC-APF with the modified calculation algorithm is verified through simulation and experimental studies.

Control shunt active filter based on dq frame using current model prediction

The nonlinear loads present more in the power systems in the practice today by developing of electronic technology and using the small distributed power sources (solar power, wind power etc.), this causes the increasing the high frequency switch devices etc. in the power network. Nonlinear loads cause non-sinusoidal currents and voltages with harmonic components, increasing the reactive power, overload of power lines and electrical devices, low power factor and affecting badly to the networks. Shunt active filters (SAF) with current controlled voltage source inverters (CCVSI) are used effectively to reduce the harmonics and to balance the phases sinusoidal source currents by generating the currents to compensate the harmonic currents caused by the nonlinear loads. In this paper we suppose a control strategy to generate the compensation currents of SAF by using the current model predictive engineering. This method is better than the control strategy using PI controller in term of transient time. The desired compensation currents can track exactly the reference compensation currents on the dq frame. The simulation results implemented on the nonlinear load, a full bridge rectifier and 3 phase unbalance load, show that the transient period decrease from 0.1s to 0.02s in comparing with PI controller. The experimental results proof that the THD of source currents decrease from 24.8% to 5.4% when using the proposed method.

An Efficient Shunt Active Filter for Harmonic Reduction in Hospital Building Electrical Installation

This paper proposes an efficient shunt active filter for harmonic reduction in hospital building electrical installation. Harmonic installation in distribution system is caused by non-linear electrical loads, especially those containing coils, such as air conditioners, pump machines, fans, and others. Harmonic can cause excessive heat in a distribution transformer that supplies an electrical installation in a multi-storey building. This heat is a power loss and has the potential to shorten the life of a distribution transformer, so that efforts are needed to reduce harmonics. One effective method to reduce harmonics is to use active filters. In this study, a shunt active filter application in the electrical installation of a hospital building was carried out. The results showed that the filter was able to reduce harmonic currents significantly, so that the harmonic threshold was still in accordance with the IEEE standard.

A four-switch shunt active filter based on one cycle control for compensating non-linear loads

ABSTRACT This paper introduces a Four-Switch Three-Phase Shunt Active Power Filter (FSTP-APF) based on One Cycle Control (OCC) technique for compensating the currents of three phase non-linear loads. The power stage of FSTP-APF uses only four semiconducting switches which leads to reduce the overall cost of APF. The proposed technique retains the advantages of the conventional OCC, such as no reference current calculation, no need for using Phase-Locked Loop (PLL), very simple control circuit and constant switching frequency. In addition, the modification reduces the number of semiconductor switches, reduces the filter output inductances, reducing the number of sensors to only four sensors, two of them for measuring supply currents and the others for measuring DC-link voltages, and the control algorithm becomes simpler. The feasibility and performance of the proposed technique are demonstrated through the simulation and experimental verifications.

On the Use of the p-q Theory for Harmonic Current Cancellation with Shunt Active Filters

Discussion and mathematical proof on necessary and sufficient conditions for the application of the {p-q} theory for compensating the harmonic currents consumed by non-linear load using a shunt active filter are presented. These conditions over instantaneous active and reactive powers were not addressed before and must be considered on the design of new control strategies based on {p-q} theory. Theoretical demonstration is proposed and an application example with simulations results is used to validate the theoretical results.

Pengaruh Fuzzy Logic Controller Pada Pengoperasian Filter Aktif Shunt Terhadap Penurunan ITHD dan Rugi-Rugi Daya Pada Sistem Kelistrikan RSUD Klungkung

RSUD Klungkung is supplied by a transformer with a capacity of 200 kVA. The use of non-linear loads in Klungkung Hospital can cause harmonic currents (ITHD). The greater the harmonic current produced, the quality of the electrical power will get worse, causing losses to the transformer. The installation of active shunt filters and the use of fuzzy logic controllers as controllers on filters can reduce the harmonics that occur in the electrical system. The results of ITHD measurements on existing conditions for R phase are 11.23%, S phase is 14.72%, and T phase is 11.20%. The ITHD value decreased when the system was paired with a shunt active filter for R phase of 5.24%, S phase was 7.18%, and T phase was 5.34%. The ITHD value has decreased again when the use of fuzzy logic controller for R phase is 0.15%, S phase is 0.17%, and T phase is 0.11%. Decreasing ITHD values affect the losses generated on the system. In the existing conditions losses are 10.525%, losses in the operation of the shunt active filter are 1.352%, and the use of fuzzy logic controller produces the smallest losses of 0.00035%.

Performance analysis of a multilevel inverter based shunt active filter with RT‐EMD control technique under ideal and non‐ideal supply voltage conditions

In this study, a real-time empirical mode decomposition (RT-EMD) based control technique is adopted for effective mitigation of system harmonics under ideal and non-ideal supply voltage conditions. The proposed control algorithm takes the active component of load current samples and the positive sequence voltage component for generating the desired reference. The fundamental component of load current is found by employing RT-EMD, which decomposes the distorted non-linear sample into a finite number of fine-scale signals termed as intrinsic mode function (IMF). Each IMF is extracted adopting continuous calculation of upper and lower envelopes using a series pipeline structure which decreases the computational complexity. The proposed control algorithm takes the positive sequence voltage component for generating the desired reference so that the system can operate in non-sinusoidal grid voltage conditions. The proposed control algorithm adopts carrier-based modulation scheme for switching of the inverter module. The effectiveness of the proposed control approach is investigated in MATLAB-Simulink environment with balanced and unbalanced loading condition and its experimental validation is carried out by a hardware prototype model using a Spartan 6 FPGA controller.

Modeling and performance analysis of shunt active filter connected with photovoltaic system based on Z-source inverter

PurposeThis paper aims to propose a new configuration of a shunt active power filter (SAPF) connected with a photovoltaic (PV) system through a Z-source inverter (ZSI) topology. This topology ensures a single-stage operation and overcomes the limitations of the conventional two-stage operation topologies based on the DC–DC boost converter. The proposed system is designed for the purpose of reducing the total harmonic distortion of the source current by eliminating the current harmonics and exploiting the solar irradiation.Design/methodology/approachFirst, all the main parts of the proposed shunt active power filter are fully described in this paper, and then a PV system based on a Z-source inverter with a maximum power point tracking controller is used to exploit the solar irradiance and solve the problem of discharging of the direct current (DC) capacitor during the filtering process.FindingsFrom the extensive simulation tests carried out using MATLAB/Simulink, the obtained results prove that the proposed shunt active power filter performs well despite several operation scenarios, including different load types and under abrupt irradiance.Originality/valueA new shunt active power filter configuration has been proposed. This configuration benefits from the solar irradiation and overcomes the drawbacks of the conventional configurations by using the Z-source inverter instead of the voltage source inverter and DC–DC boost converter.

Implementation of Solar Photovoltaic System With Universal Active Filtering Capability

In this paper, a novel technique based on a second-order sequence filter and a proportional resonant controller is proposed for the control of a universal active power filter integrated with a photovoltaic array (UAPF-PV). Using a second-order sequence filter and sampling it at zero-crossing instant of the load voltage, the active component of the distorted load current is estimated, which is used to generate a reference signal for a shunt active filter. The proposed method has good accuracy in extracting a fundamental active component of distorted and unbalanced load currents with reduced mathematical computations. Along with power quality improvement, the system also generates clean energy through the PV array system integrated to its dc link. The UAPF-PV integrates benefits of power quality improvement and distributed generation. The system performance is experimentally evaluated on a prototype in the laboratory under a variety of disturbance conditions, such as point of common coupling voltage fall/rise, load unbalancing, and variation in solar irradiation.

Implementation of EMD‐based control algorithm for a cascaded multilevel inverter–based shunt active filter

Implementation of EMD‐based control algorithm for a cascaded multilevel inverter–based shunt active filter