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The escalating integration of renewable energy sources along with the prevalence of nonlinear loads in electric power systems have heightened power quality (PQ) issues. In response, this research proposes a novel distribution static compensator (DSTATCOM) design featuring a three-phase single-source five-level inverter for distributed power systems based on wind energy conversion systems. The multi-level inverter (MLI) adopts a single DC source and minimum switch count, prioritizing simplicity. A radial basis function neural network (RBFNN) assisted p-q theory-based control, coupled with a genetic algorithm tuned proportional integral (PI) controller, ensures effective compensation and stable dc-link voltage. Simulation models and a laboratory prototype confirm the effectiveness and dynamic compensation capabilities of the presented DSTATCOM design across various load conditions. Results reveal stable grid-side parameters, low total harmonic distortion (THD), and the maintenance of a unity power factor. The hardware analysis confirms reduced THD values post-compensation, 2.174% for voltage and 1.898% for current, attesting to the DSTATCOM's efficacy in improving PQ. The proposed design outperforms conventional MLI topologies in terms of component count, reliability, and simplicity. The introduced RBFNN exhibits superior harmonic extraction, achieving a minimal prediction error of 1.3 × 10 - 8 . This work establishes the effectiveness of the proposed DSTATCOM in enhancing PQ in distributed power systems, setting the stage for further optimization and integration of advanced control strategies. [ABSTRACT FROM AUTHOR]

This paper presents a simple and effective sensorless control strategy based on extended state observers (ESOs) to enhance the performance of brushless DC (BLDC) motors. First, an ESO is used to estimate the back-electromotive force (EMF) without additional filters. Second, another ESO is incorporated into the quadrature phase-locked loop (QPLL) to enable the implementation of an active harmonic compensator to reduce noise harmonics induced by the estimated back-EMF. By using the P-Q theory, the proposed compensator calculates a compensation signal to be directly injected into the QPLL based on ESO. The results analysis shows that the proposed strategy significantly reduces torque ripples and speed/position estimation errors under a wide range of speeds. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The increasing use of power electronic devices has resulted in harmonics that may cause in power systems overheating of equipment, poor power factor and voltage distortion. Shunt active power filter (SAPF) provides the most useful means for harmonics mitigation in power systems. In a certain number of SAPFs, the dc link capacitor voltage is regulated by means of a PI controller. This paper proposes a variant of a population based Jumping Spider Algorithm for optimal tuning of the PI controller to enhance the performance of the active filter. The SAPF considered in this paper uses the p-q theory to extract its reference current and the hysteresis current control to produce the triggering signals for the controlled switching devices of its inverter. The overall SAPF is developed and validated using MATLAB/Simulink tool under two different nonlinear loading conditions. The results obtained by simulation show that the SAPF with the proposed PI controller effectively controls the dc-link capacitor voltage and mitigates current harmonics.

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In recent years, electronic transformers and electronic devices (nonlinear loads) have increased. These loads are the source of harmonics (non-sinusoidal and distorted waves) and the interactive force that affects the performance of the power system network. Also, it badly affects the power factor and electrical energy on the scales of efficiency and quality. For this reason, a system called “Active Power Filters” has been adopted. It provides an effective alternative to traditional LC passive power filters. It can improve network performance by treating and reducing harmonics, improving power factor and quality, avoiding resonance between the filter and the network, and reducing reactive power. This paper presents a study on the shunt active power filters device and how to connect it to the distribution network and A review of the bathing control strategies in the methods of calculating current and power, methods of controlling the PWM device, the most prominent techniques for improving the PID control system, and the most prominent algorithms applied in that to improve the safety performance of the Shunt Active Power Filter (SAPF) on the one hand and to demonstrate the ability of different systems to compensate for THD on the other hand. APF performance fluctuates from one control strategy to another. It reduced (THD) between 0.9% and 13% in several control techniques applied with PWM. The aim of this paper is to illustrate the techniques applied to control the performance of the "Shunt Active Power Filter" to reduce THD

In this article, the authors present the analysis and simulation process in the Simulink/MATLAB environment for a three-phase active power filter. Active power filters are used in power distribution systems to compensate for voltage and current disturbances. The Simulink model reproduces the key components of the filter, and simulations allow evaluation of its performance. The aim is to optimize the parameters and the control algorithm, thus ensuring a superior quality of the supplied electricity. This approach contributes to the development of more efficient and reliable electrical power distribution systems by providing a deeper understanding of the behavior and performance of the three-phase active power filter. [ABSTRACT FROM AUTHOR]

Rectifier is a non-linier load that causes harmonic distortion in the power system. Pulse-width modulation (PWM) method is an effective method in pressing the magnitude of harmonics in a rectifier application, it provides an almost sinusoidal input current. However, the variation of loads that supplied by a rectifier cause the harmonics that arise can still beyond the applicable standard. The amount of harmonics in the operating range of a rectifier need to be identified to determine the filter on the input side. In this research article, 3-phase PWM rectifier was designed with hysteresis current control technique using PSCAD software simulation. Harmonic compensation was carried out by applying an active filter based on P-Q theory to reduce the harmonic distortion that occurs in the input current, thus giving a low total harmonic distortion (THD) value. Based on the simulation, 3-phase PWM rectifier operation starting at a power level of 150 kW, giving a THD value above 5-10% by the increasing the amount of load supplied by the rectifier. The application of active filter based on the P-Q theory is able to compensate harmonics in the input current wave with a THD value below 5% in the rectifier operating range.

The increasing use of power electronic devices has resulted in harmonics that may cause in power systems overheating of equipment, poor power factor and voltage distortion. Shunt active power filter (SAPF) provides the most useful means for harmonics mitigation in power systems. In a certain number of SAPFs, the dc link capacitor voltage is regulated by means of a PI controller. This paper proposes a variant of a population based Jumping Spider Algorithm for optimal tuning of the PI controller to enhance the performance of the active filter. The SAPF considered in this paper uses the p-q theory to extract its reference current and the hysteresis current control to produce the triggering signals for the controlled switching devices of its inverter. The overall SAPF is developed and validated using MATLAB/Simulink tool under two different nonlinear loading conditions. The results obtained by simulation show that the SAPF with the proposed PI controller effectively controls the dc-link capacitor voltage and mitigates current harmonics. [ABSTRACT FROM AUTHOR]

In the present-day decade, the world has regarded an expansion in the use of non-linear loads. These a lot draw harmonic nonsinusoidal currents and voltages in the connection factor with the utility and distribute them with the useful resource of the overall performance of it. The propagation of these currents and voltages into the grids have an effect on the electricity constructions in addition to the one of various client equipment. As a result, the electrical strength notable has come to be critical trouble for each client and distributor of electrical power. Active electrical electricity filters have been proposed as environment splendid gear for electrical power pinnacle notch enchantment and reactive electrical strength compensation. Active Power Filters (APFs) have Flipped out to be a possible wish in mitigating the harmonics and reactive electrical electricity compensation in single-phase and three-phase AC electrical energy networks with Non-Linear Loads (NLLs). Conventionally, this paper applied Ant Colony Algorithm (ACO) for tuning PI and reduce Total Harmonic Distortion (THD). The result show reduces THD at 2.33%. [ABSTRACT FROM AUTHOR]

This paper presents a load-shift system with advanced functionalities for the power grid. When compared with the conventional approach, an advanced load-shift system allows the compensation of power quality problems on the power grid side, namely problems related to current harmonics, current imbalances, and low power factor. The advanced load-shift system is composed by a bidirectional ac-dc converter to interface the power grid and by a bidirectional dc-dc converter to interface an energy storage system. Since the main innovation is related with the power grid interface, the focus of this work is on the analysis of the ac-dc converter, which is based on a three-phase four-leg voltage source converter. A theoretical study and the details concerning the control algorithm are presented and discussed along the paper. A laboratory prototype of the advanced load-shift system was developed, and the main details of implementation are described in the paper. Experimental results obtained with the developed prototype prove that the advanced load-shift system contributes for the technology progress in this area, validating a new operation concept concerning the power quality on the power grid side. For all the operation modes, the system operates with high power factor and the currents on the power grid side are balanced with a low total harmonic distortion and in phase with the respective power grid voltages.

This paper presents a load-shift system with advanced functionalities for the power grid. When compared with the conventional approach, an advanced load-shift system allows the compensation of power quality problems on the power grid side, namely problems related to current harmonics, current imbalances, and low power factor. The advanced load-shift system is composed by a bidirectional ac-dc converter to interface the power grid and by a bidirectional dc-dc converter to interface an energy storage system. Since the main innovation is related with the power grid interface, the focus of this work is on the analysis of the ac-dc converter, which is based on a three-phase four-leg voltage source converter. A theoretical study and the details concerning the control algorithm are presented and discussed along the paper. A laboratory prototype of the advanced load-shift system was developed, and the main details of implementation are described in the paper. Experimental results obtained with the developed prototype prove that the advanced load-shift system contributes for the technology progress in this area, validating a new operation concept concerning the power quality on the power grid side. For all the operation modes, the system operates with high power factor and the currents on the power grid side are balanced with a low total harmonic distortion and in phase with the respective power grid voltages. [ABSTRACT FROM AUTHOR]

Power converters affected by nonlinear loads cause the current from the grid. Because of this harmonic distortion current and voltage wave forms of grid becomes sum of the fundamental component and other sinusoidal components having different frequency and amplitude. Design of active power filters with the recent advances in microcontroller technologies has gained momentum in order to use the electrical energy in a more efficient way by removing the harmonic effects on the grid caused by nonlinear electrical loads or by compensating the distortive effects of the grid in order to prevent the load to be affected. In this study, available active power filter topologies in literature have been classified and three different types of filters have been simulated by using p-q instantaneous power theory to create a comparison table in which the selection criteria of active power filters based on the component to be compensated have been stated.

In this paper, dynamic performance of a transformerless cascaded PWM static synchronous shunt compensator (STATCOM) based on a novel control scheme is investigated for bus voltage regulation in a 6.6kV distribution system. The transformerless STATCOM consists of a thirteen-level cascaded H-bridge inverter, in which each voltage source H-bridge inverter should be equipped with a floating and isolated capacitor without any power source. The proposed control algorithm uses instantaneous p-q power theory in an innovative way that devotes itself not only to meet the reactive power demand but also to balance the dc link voltages at the same time. DC link voltage balancing control consists of two main parts: cluster and individual balancing. The control algorithm based on a phase shifted carrier modulation strategy has no restriction on the number of cascaded voltage source H-bridge inverters. Comprehensive simulations are presented in MATLAB/ SIMULINK environment for validating the performance of proposed transformerless STATCOM.

Harmonic Distortion in many of the industrial applications are occur primarily owing to the enormous utilization of loads with high non-linearity like power converters, speed varying drives and arc furnaces. The power semiconductor is used to achieve the variation in speed and conversion from one source to another. Mostly active filters and tuned filters are utilized to remove the harmonic included in the source current. The tuned passive filters and inductance inserted in the line reduces the harmonics but at the same time induces the resonances in most of the industrial applications. Due to this, harmonic distortion increases in the source current and voltage. This can be reduced by adding hybrid filter in the system with decreased rating of active filter in high power applications. This article deals with the various topology of hybrid filters. The working of the proposed filter design in variable inductance mode based on the pollution created in the source voltage and current is studied. In the proposed hybrid filter passive filter is tuned with seventh harmonic frequency and connected in series with active filters to reduce the harmonic distortion. DC link voltage and the active filter VA rating could be minimized. The control signal to the filter is derived from p-q theory and space vector pulse width modulation (SVPWM). The performance of the system under study is simulated and noted for the THD percentage before and after the filter is added to the system and the same model is experimented with reduced voltage level. [ABSTRACT FROM AUTHOR]

For the past two decades, tremendous advancements have been achieved in the electricity industry. The usage of non-linear loads in the daily life has affected the power quality of the system and caused the presence of harmonics. To compensate the harmonic currents and reactive power in the system, the design of shunt hybrid active power filter has been proposed in this research. The design of the filter has included several control systems of instantaneous active and reactive power (p-q) theory and PI controller to investigate the performance of the filter. The robustness of the designed hybrid power filter has also been benchmarked with the other filter topologies available in literature. The hybrid power filter will combine passive power filter and active power filter configurated in shunt connection. The result of this research showed that the total harmonic distortion analyzed is below than 5% according to IEEE-519 standard requirements and reactive power is compensated proved by the increase in power factor. The shunt hybrid active power filter is designed, and simulation result is analyzed by using MATLAB-Simulink environment. [ABSTRACT FROM AUTHOR]

In order to face the challenges due to the large-scale integration of photovoltaic (PV) inverters on the distribution side, the grid-connected PV inverters are expected to provide certain ancillary services. These ancillary services include reactive power support, low voltage ride through (LVRT), and harmonic compensation, just to name a few. In this article, the LVRT capability of a $\ddot{\text{C}}$ uk-derived novel inverter, 6sw- $\ddot{\text{C}}$ uk derived transformer-less inverter (6sw-CDTI), suitable for transformer-less grid–PV interface, is explored. The transformer-less inverter, 6sw-CDTI, considered in this work can provide the desired ancillary services more efficiently and at a lesser cost as compared to the conventional inverters. Reactive power support to the grid can be provided without distorting the injected current by 6sw-CDTI with no dc injection due to symmetrical operation in both half cycles. Besides this, the leakage current elimination is not affected because the topological structure is not altered. Experimental results obtained from a 200-W laboratory prototype illustrate how additional control features can be integrated in the inverter control scheme for LVRT. Single-phase instantaneous p-q theory is used for inverter control, and a feed-forward component is added in the control scheme for improved dynamic response. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The active power filter designed to compensate inactive power components. Aim: The aim of the study is to assess the quality of the three-phase active power filter in the distortion of the mains voltage supply, which is caused by the influence of non-linear loads, and then comparing the two active filtering algorithms - Fryze power theory and p-q theory of instant power. Materials and Methods: Reviewed a three-phase active power filter connected in parallel to the mains via inductance. To study the modes of filter with non-linear loads with non-sinusoidal voltage programmed in Matlab/Simulink the model of electricity system is implemented. As the algorithm of implementation for determining of inactive components of power the Fryze theory and p-q theory were considered. Results: Obtained a time diagrams of network current after compensation when applying the theory of Fryze and p-q theory. Built the graphs of efficiency of reactive power compensation, fall of coefficient of network current distortion and errors of active power under the changing of firing angle of thyristor converter.

This paper principally advises a simple and reliable control for Static Synchronous Compensator (STATCOM) in a stand-alone wind driven self-excited induction generator power system. The control was proposed based on instantaneous P-Q theory. The advised control enjoys the merits of robustness, reliability and simplicity. The paper also proposes a dimensioning procedure for the STATCOM that involves advising an annotative analytical expression for sizing the DC-link capacitor. This procedure has the advantages of applicability for different reactive power compensators that depend on a separate DC-link in its operation. Comprehensive simulation results in Matlab environment were illustrated for corroborating the performance of the advised control under rigorous operating scenarios. The results show the feasibility, reliability and practicability of the proposed controller.

The research work proposes, Design and implementation of Solar power fed permanent magnet synchronous motor using improved DC-DC Converter and modified p-q theory based shunt active filter for reducing vibrations in drive for Industrial Applications. The Proposed research consists of both buck and boost converter, linking dc voltage unit and works in discontinuous conduction for boosting the battery life time. The improved converter provides multiple output capability using B4-inverter which reduces the cost of a proposed system considerably. In addition, for the reduction of harmonics in three phase system modified p-q module is enhanced. Comparing with the existing module, modified p-q module act as a triggering module for inverter to reduce harmonics in three phase systems and vibration across the motor, moreover the structured circuit would result in reduction of total harmonic distortion (THD), torque ripples, compact power switches, DC source reckoning and reduced starting current. The simulation of buck boost converter is considered, and its performance parameters were analyzed for different operating conditions. Thus, for industrial applications, the bidirectional converter and inverter fed permanent magnet synchronous motor drive is employed with the reduction in vibration, which is more efficient than conventional method. Here both simulation and experimental setup has been employed with a satisfying closed loop performance. [ABSTRACT FROM AUTHOR]

Due to intensive use of power converters and other non-linear loads, power quality is degrading. The presence of harmonics in the power lines result in greater power losses in distribution, interference problems in communication systems. Non linearity reduces the efficiency and power factor of the system. As the power factor reduces, the reactive power demanded from the supply increases which have no any contribution in energy transfer, so compensation is required. For this, shunt passive filter has been developed but it is bulky and frequency dependent and has many drawbacks. In contrast to passive filter, shunt active filter (SAF) has been developed which is smaller and has wide range of applications. In this paper, shunt active filter based on p-q theory is demonstrated for compensating reactive power and current harmonics. Simulation has been done with and without SAF and results are presented and ended with recommendation and conclusion. An effort is made to reduce the THD of the source current below 5% (specified by IEEE). [ABSTRACT FROM AUTHOR]

The accurate determination of the load harmonic current is one of the important factors, it decides to effect of harmonic filtering and reactive power compensation for Hybrid Active Power Filter. The p-q harmonic detection method has been widely used in determining the harmonic currents of Hybrid Active Power Filter. However, when using this method, the dynamic response of Hybrid Active Power Filter in the transient period will have a large transient time and overshoot whenever the load changes abruptly. Therefore, in this paper an improved p-q harmonic current detection method based on fuzzy logic is proposed, which aims to reduce the overshoot and transient time in transient duration of Hybrid Active Power Filter. In order to compare the dynamic response of conventional and improved p-q harmonic detection methods, simulation results have demonstrated that: the proposed method has a shorter response time, the magnitude of the supply current in the transient time is smaller and the overshoot of the fundamental active and reactive power components is very small. This has a practical significance that contributes to the stability of the Hybrid Active Power Filter system. [ABSTRACT FROM AUTHOR]

The paper deals with grid connection circuits for active filters, structures of active power filter control systems, and methods based on full capacity components determination. The existing structures of active power filter control and control algorithm adjustment for valve commutation loss reduction are analyzed. A predictive control algorithm for an active three-phase power filter is introduced.

This paper proposes a novel application of the instantaneous P-Q theory in a wind energy conversion system (WECS). The proposed WECS is formed by permanent magnet synchronous generator (PMSG) wind turbine system connected to the grid through parallel active power filter (PAPF). PAPF uses the generated wind energy to feed loads connected at the point of common coupling (PPC), compensates current harmonics and injects the excess of this energy into the grid using P-Q theory as control method. To demonstrate the feasibility and the performance of the proposed control scheme, simulation of this wind system has been realized using MATLAB/SIMULINK software. Simulation results show the accuracy and validity of the proposed control scheme for the PMSGPAPF system.

The use of nonlinear loads has increased in power systems consequently the harmonic currents have also increased causing detrimental effects to the supply system and user equipment. The aim of the present paper is to identify harmonics in order to obtain a perfect compensation by active power filter (APF). A study of harmonic currents identification by two different methods is conducted in this work. The instantaneous power (PQ) theory method requires two low-pass filters for the extraction of direct power components from total power components. However the direct neural method based on ADALINE neural network method estimates total harmonic current as well as harmonic components separately. Moreover, the identification of each component separately enables the selective compensation of harmonics by the active filter if the objective is to minimize the cost. The method is easy to implement in real time compared to PQ method. In present paper two algorithms based on conventional PQ method and direct neural method were developed in order to identify the harmonic currents. These developed algorithms are confirmed by experimental tests by implementing these techniques in a dSPACE controller in order to show their effectiveness. The obtained results are compared, discussed and analyzed. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive study on the performance of Shunt Active Harmonic Filter (SAHF) for harmonic compensation, where Ant Colony Optimization technique is used for optimization purpose. This optimization technique operates for the optimal PI control parameters which regulate the DC link voltage. Instantaneous real and reactive power (p-q) theory is used for calculating compensating currents. The simulation results show that Shunt Active Harmonic Filter (SAHF) for six pulse controlled rectifier proves to be very effective in mitigation of the harmonics present for various firing angles. The simulation is carried out with the help of MATLAB-SIMULINK tool box. [ABSTRACT FROM AUTHOR]

Two different techniques of P-Q instantaneous power theory mathematical apparatus modernization for shunt active filters are analyzed. Both techniques are equal in nature while different in implementation. The modernization concepts introduced allow correcting imperfection of the P-Q theory under conditions of unbalanced and non-sinusoidal supply voltage systems.

This paper presents a single-phase Shunt Active Power Filter (SAPF) with a multilevel converter based on an asymmetric full-bridge topology capable of producing five distinct voltage levels. The calculation of the SAPF compensation current is based on the Generalized Theory of Instantaneous Reactive Power (p-q theory) modified to work in single-phase installations, complemented by a Phase-Locked Loop algorithm and by a dedicated algorithm to regulate the voltages in the DC-link capacitors. The control of the SAPF uses a closed loop predictive current control, followed by a multilevel Sinusoidal Pulse-Width Modulation technique with two vertical distributed carriers, which were specially conceived to deal with the asymmetric nature of the converter legs. Along the paper, some simulation results are used to show the main characteristics of the 5-level converter and control algorithms, and the hardware topology and control algorithms are described in detail. In order to demonstrate the feasibility and performance of the proposed SAPF based on a 5-level converter, a laboratory prototype was developed and experimental results obtained under diverse conditions of operation, with linear and non-linear loads, are presented and discussed in this paper.

Study of three-phase active power filter operation using non-sinusoidal voltage. The active power filter designed to compensate inactive power components. Aim: The aim of the study is to assess the quality of the three-phase active power filter in the distortion of the mains voltage supply, which is caused by the influence of non-linear loads, and then comparing the two active filtering algorithms ⎯ the Fryze power theory and p-q theory of instant power. Materials and Methods: Reviewed a three-phase active power filter connected in parallel to the mains via inductance. To study the modes of filter with non-linear loads with non-sinusoidal voltage programmed in Matlab/Simulink the model of electricity system is implemented. As the algorithm of implementation for determining of inactive components of power the Fryze theory and p-q theory were considered. Results: Obtained a time diagrams of network current after compensation when applying the theory of Fryze and p-q theory. Built the graphs of efficiency of reactive power compensation, fall of coefficient of network current distortion and errors of active power under the changing of firing angle of thyristor converter. [ABSTRACT FROM AUTHOR]