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Numerous types of shunt active power filters have been proposed in many papers. The classification of these filters depends on various points of view. However, every type of a shunt active filter, which compensates non‐active component of load current, irrespective of the method used to detect this component and control strategies of the filter, should keep supply source current equal to active current of a load‐and‐filter circuit. This goal can be achieved in many ways, using various structures of active filters. But different realizations of filters cause differences in their properties. This paper, which is meant to serve as a review and synthesis of earlier work, shows some possibilities of forming of single‐phase shunt active filter behaviour. The following active filter properties are discussed: operation with an immediate reaction in the supplying source branch to a load current change, and with the reaction only once in each supplying source cycle; regulation by the filter of the non‐active current component of fundamental frequency; active filtering and simultaneous feeding of DC load with stabilizing DC voltage; operation with stabilization of supplying source current amplitude; reducing filter switching frequency; and reducing current distortions in the supplying source branch. All the waveforms presented were produced using a computer simulation method.

Shunt active power filters are used to decrease or almost eliminate non‐active currents flowing through the supply source. Numerous control methods of active filters have been proposed in many papers. The aim of this paper is to demonstrate a simple but very effective method of obtaining the compensated load active current.

The method allows one to control the shunt active power filter only by monitoring energy stored in the filter. Based on the introduced generic structure of the filter the changes of filter energy are examined in order to obtain the reference current for the filter compensation action.

This presented method can be implemented to nearly all structures of active filters. It is suitable not only for the single‐phase but also for the three‐phase circuit. Such energy‐controlled filters may be built on the basis of voltage‐ and current‐source inverters as well.

This paper provides an alternative approach to address the problem of the shunt active filter control method. The paper shows that monitoring the filter's energy suffices for proper control of the filter compensation action.

The purpose of this study is to find a control method for three-phase four-wire shunt active power filters, which uses a load-equivalent conductance for obtaining a reference signal for compensating non-active current.

Changes of energy stored in an active filter’s reactance elements are monitored to find the active component of the load current. It is then used as a current reference to be realised as a supply source current. Computer simulation methods were used to verify the presented control method.

To calculate the reference signal for the active filter action, it is enough to measure the active filter’s DC-side capacitors’ voltages. It has been proved that P regulators are sufficient to realise compensating current and to stabilise active filter capacitors’ voltages. The supply source-neutral conductor current can be zeroed even for nonlinear and unbalanced load-generating DC-component in its neutral conductor. In addition, the active filter can buffer load-active power changes and act simultaneously as a local energy accumulator.

This paper provides an alternative approach to address the problem of the three-phase four-wire shunt active power filter control methods.

Examines some basic aspects of hybrid filters, operating effectively when current pulsations of a non‐linear variable load occur. The operation of two hybrid filter systems, each equipped with an active power filter, working as: a) a controlled additional current source, b) a controlled additional voltage source, recognized by the authors in previous publications as the most advantageous solution has been examined. For both systems, vectorial equations in α,β co‐ordinates, describing their operation, have been presented. On the basis of these equations a common frequency model of three‐phase three‐wire hybrid filters has been elaborated. This model has been used for the evaluation of the filtration efficiency of line current harmonics, taking into consideration the applied methods and algorithms to separate filtered harmonics, above all at a pulsating load current. Some conclusions from the theoretical analysis have been verified by simulation of a line loaded by converter with an output current pulsating at frequencies 10 and 20Hz.

This paper aims to achieve two main objectives. First, to introduce to the literature a new versatile active building block, namely, voltage differencing differential voltage current conveyor (VD-DVCC) for analog signal processing applications. Second, to design a novel electronically tunable mixed-mode universal filter. The designed filter provides low-pass, high-pass, band-pass, band-reject and all-pass responses in voltage-mode (VM), current-mode (CM), trans-impedance-mode (TIM) and trans-admittance-mode (TAM).

The proposed filter uses two VD-DVCCs, three resistors and two capacitors. All the capacitors used are grounded, which is advantageous from the monolithic integration point of view. The VD-DVCC is designed and validated in Cadence software using CMOS 0.18 µm process design kit from Silterra Malaysia at a supply voltage of ±1 V.

The proposed novel filter enjoys many attractive features including as follows: the ability to operate in all four modes, no requirement of capacitive matching, tunability of quality factor (Q) independent of pole frequency, availability of both inverting and non-inverting outputs for VM and TIM mode, high output impedance explicit current output for CM and TAM, no requirement for double/negative input signals (voltage/current) for response realization and low active and passive sensitivities. The filter is designed for a pole frequency of 5.305 MHz. The obtained results bear a close resemblance with the theoretical findings.

The proposed novel filter structure requires a minimum number of active and passive components and provides operation in all four operating modes. The filter will find application in structures of mixed-mode systems.

The purpose of this paper is to present the concept and design methodology for unified, LCL interfacing circuit intended for a high power, modular active power filtering system. The paper aims to contain simulations and selected measurements of an industry applied system.

The design methodology of unified LCL circuit is based on an analytical model of the system and practical requirements for an active power filter. The stability of the system is confirmed by using poles of discrete transmittance of the close loop system.

The paper reveals the topology and design methodology of the unified LCL circuit for a high power, modular active power filtering system. The circuit permits zero current ripples, high dynamics of compensating currents, and full scalability of the system.

The practical implications of this paper are in the industrial applications of high power, modular active filtering system.

The topology of unified LCL filter and its design methodology for a modular active power filtering system are of value. It also provides a stability analysis for the system with model‐based predictive current controller.

This 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.

First, 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.

From 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.

A 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.

The active power filter with two-level inverter needs a high-rating coupling transformer for high-power applications. This complicates the control and system becomes bulky and expensive. The purpose of this paper is to motivate the use of multilevel inverter as harmonic filter, which eliminates the coupling transformer and allows direct control of the power circuit. The advancement in artificial intelligence (AI) for computation is explored for controller design.

The proposed scheme has a five-level cascaded H-bridge multilevel inverter (CHBMLI) as a harmonic filter. The control scheme includes one neural network controller and two fuzzy logic-based controllers for harmonic extraction, dc capacitor voltage balancing, and compensating current adjustment, respectively. The topology is modeled in MATLAB/SIMULINK and implemented using dSPACE DS1103 interface for experimentation.

The exhaustive simulation and experimental results demonstrate the robustness and effectiveness of the proposed topology and controllers for harmonic minimization for RL/RC load and change in load. The comparison between traditional PI controller and proposed AI-based controller is presented. It indicates that the AI-based controller is fast, dynamic, and adaptive to accommodate the changes in load. The total harmonic distortion obtained by applying AI-based controllers are well within the IEEE519 std. limits.

The simulation of high-power, medium-voltage system is presented and a downscaled prototype is designed and developed for implementation. The laboratory module of CHBMLI-based harmonic filter and AI-based controllers modeled in SIMULINK is executed using dSPACE DS1103 interface through real time workshop.

The purpose of this paper is to propose a new hybrid control method of pulse width modulation (PWM) active rectifiers tied to the grid through an LCL filter. The control method is designed with the aim to achieve a perfect regulation of the dc-bus voltage; a near unity input power factor (UIPF) operation as well as a high quality of the line currents.

The proposed hybrid control method consists of a PI-based linear controller cascaded with a nonlinear one. The nonlinear controller (inner loop) is designed using the input-output feedback linearization (IOFL) theory. It should control both the dc-bus voltage and the input currents at the converter’s poles. The linear controller (outer loop) is devoted to control the reactive line current so as to achieve a near UIPF.

A perfect regulation of the dc-bus voltage and a near UIPF operation are achieved. Moreover, a high quality of the line currents is obtained. The robustness and effectiveness of the proposed control method have been successfully tested under variation of the dc voltage reference as well as grid and load disturbances.

The proposed method is useful for single-stage and two-stage grid connected photovoltaic systems, wind energy conversion, and distributed power generation systems.

The main novelty of this paper is the combination of linear and nonlinear controllers with the aim to control a PWM active rectifier tied to the grid through a third-order LCL filter. In the opinion, such control method has not been applied to this converter in earlier research papers. The numerical simulations carried out under normal and abnormal conditions confirm the effectiveness of the proposed approach.

The paper aims to explain the investigation of the space vector modulation (SVPWM), in shunt active powers filters (APFs) field, for controlling the generated current.

With the inclusion of the SVPWM control technique, the proposed topology of the two‐level shunt active power filter (APF), based on IGBTs, besides its efficiency in harmonics cancellation and power factor correction, contributes in switching power losses reduction.

The paper provides an extended theoretical study and a detailed explanation of the application of the SVPWM on shunt APFs, and demonstrates how power losses can be reduced by limiting the switching process to the two thirds of the pulse duty cycle.

Simulation and experimental validations will still be requested as to the accuracy of the model and the applicability to the polluted electrical power systems plants.

The paper formulates an easy mathematical method to investigate the SVPWM algorithm with clarification of its various steps. It offers a benefit to people engaged in theoretical and practical research in APFs, inverters, and PWM modulation strategies.

Since, there are few studies which clarify the application of the SVPWM on APFs, the paper may help to understand the mathematical implementation of this control strategy both for controlling the APF current and for gating signals generation.