Shunt Hybrid Active Power Filter Research Articles

Improved performance of a shunt hybrid active power filter by a robust exponential functional link network-based nonlinear adaptive filter control to enhance power quality

This research article details the design and implementation of a nonlinear adaptive filtering (NAF) technique using an exponential functional link network (EFLN) for a shunt hybrid active power filter (SHAPF) control to solve the current-associated power quality issues on the utility side at the distribution level of electrical power systems. Separation of the fundamental component from the harmonics, achieving unity power factor operation, reducing the reactive power drawn from the source, balancing the currents during transients, and reduction of total harmonic distortion (THD) of the source current are the issues considered to resolve. The proposed technique solves these issues by generating the sinusoidal reference current and separating the fundamental current from the harmonics. When compared to conventional and existing adaptive filtering techniques such as least mean square (LMS), least mean fourth (LMF), and variable step size LMS (VSS-LMS), the proposed EFLN-NAF method excels in terms of speedy convergence, adaptability in noise-specific environments and reduced steady-state coefficient error. MATLAB/Simulink software is utilized to perform the simulations to examine the suggested strategy for the chosen SHAPF topology both in static and dynamic scenarios. For a 15 kW and 3kVAr requirement of the nonlinear load, simulation results proved that the designed PPF for 2kVAr is able to share the reactive power with the APF, thereby reducing its rating and cost. The proposed method of filtering has been proven to be fast converging with 0.049 s, and the THD in steady state is brought to 1.32 % in steady-state and to 3.77 % during transient conditions, which are under standard limits. A hardware prototype of the experimental setup is constructed at the laboratory scale with OPAL-RT (OP4510) as the controller. With an active and reactive power demand of 1.1 kW and 210VAr, the designed PPF supplies 110 VAr, whereas the rest is supplied by the APF. The practical THD in source current is observed to be 2.081 %, which meets the standards. The results from both simulations and experiments are validated, and the efficacy of the proposed technique in mitigating the aforementioned power quality issues is proved.

Grid voltage sensorless control of a single‐phase shunt hybrid active power filter

AbstractHere, a grid voltage sensorless control of an LCL‐filtered LC‐tuned single‐phase shunt hybrid active power filter (HAPF) is proposed, which offers high‐quality harmonic current compensation with low hardware requirements. An estimation algorithm replaces the grid voltage sensor and associated circuitry to reduce the size and cost. This paper presents a straightforward and accurate modelling of the suggested structure and its filtering characteristics, followed by a comprehensive yet simple parameter design procedure. An inherent damping technique that uses digital delay rather than virtual or physical damping resistors eliminates the need for additional sensors or extra power losses. As part of the design, a high‐quality reference current is generated for the filter, which is then effectively tracked using a proportional controller with sufficient bandwidth and stability margin. An experimental prototype is implemented to verify the theoretical results, and several steady‐state and transient waveforms are reported to demonstrate the superior performance of the HAPF.

Optimal power quality improvement in distribution system with UPQC using an improved strategy

AbstractA hybrid technique is proposed to enhance the power quality (PQ) on the distribution sides of the utility grid (UG) by controlling a unified power quality conditioner (UPQC) connected to hybrid sources (photovoltaic [PV] and wind turbine [WT]). The proposed hybrid method integrates the implementation of the pelican optimization algorithm and the Aquila optimizer; hence, it is called the improved aquila optimizer (IAO) technique. The objective of the proposed method is to lessen the total harmonic distortion (THD), voltage instability, and PQ issues during load fluctuation situations. The improved Aquila Optimizer technique optimizes the control parameters of the UPQC to achieve optimal PQ development. The series controller is attached to the grid‐side to enhance grid PQ, while the shunt hybrid active power filter (SAPF) and shunt active power filter (SHAPF) generate the best control pulses based on load and source conditions. The proposed solution addresses power loss, THD, and voltage instability problems during load fluctuation conditions. The series controller reduces voltage sag by 14% and voltage swell by 15%. The THD for the proposed technique is 0.8%. The PQ of the proposed technique is improved, and various characteristics are reduced. The efficiency of the proposed technique is examined by using MATLAB and is compared to existing approaches. The PQ characteristics are significantly improved, and the proposed technique is better than the existing techniques.

Novel Asymmetric/ Symmetric Half-Cascaded Multilevel Inverter for photovoltaic based shunt active power filter to mitigate power quality issues

Photovoltaic (PV) technology has been recently developing and upgrading with regard to the rapid and high request from various agricultural, domestic and industrial electric power systems. Due to feasibility and reliability of Multi-Level Inverter (MLI), it can be effectively implemented in the photovoltaic systems. The large number of switches used in the MLIs is their main drawback which leads to lack of cost-effectiveness and high Total Harmonic Distortion (THD). In this paper, a novel Asymmetric/Symmetric Half-Cascaded MLI (ASHC-MLI) which contains low number of switches is proposed to attain a cost-effective structure. After that, PV panels have been used as power sources of this structure to construct the overall Shunt Hybrid Active Power Filter (SHAPF) for mitigating the power quality problems. To evaluate the cost-effectiveness of the proposed ASHC-MLI, it has been compared with the prominent and inventive MLI structures in both asymmetric and symmetric statuses. Meanwhile, the understudy power system has been affected by different current distortions so that the harmonic elimination capability of the proposed SHAPF can be well revealed. The evaluation analysis has been simultaneously performed for the conventional active power filter to appropriately validate its harmonic elimination capability.

DT-CWT and type-2 fuzzy-HSAPF for harmonic compensation in distribution system

Extensive utilization of power electronics in different applications injects harmonics into degrading the power quality. Harmonics can be eliminated in distribution systems using low-cost passive filters, but, they become bulky and complex in design with the increase in harmonic order. Hence, active power filters (APFs) are proposed as a voltage source converter (VSC) for providing better compensation, but active filtering is costly. To minimize such demerits, this article represents a hybrid shunt active power filter (HSAPF). For reference current calculation, dual-tree complex wavelet transform (DT-CWT) is used here and conventional proportional–integral (CPI), type-1 and type-2 fuzzy logic controllers (T1FLC and T2FLC) are employed for parameter optimization of HSAPF, to enhance the harmonic compensation ability and power factor. The case studies are performed in both simulations as well as real-time experimental setup using dSPACE, and it is analyzed that the proposed DT-CWT and type-2 fuzzy-based HSAPF provide better compensation performance in comparison to other controllers under different operating conditions.

Three-phase four-wire shunt hybrid active power filter model with model predictive control in imbalance distribution networks

<span lang="EN-US">This paper presents a harmonic reduction and load imbalance model in a three-phase four-wire distribution network. This model uses a hybrid active power filter, a passive inductor and capacitor filter, and an active power filter in the form of a three-phase, four-leg connected grid inverter. The switching of the voltage source converter on this filter uses finite control set model predictive control (FCS-MPC). Control of this hybrid active power filter uses model predictive control (MPC) with a cost function, comparing the reference current and prediction current with mathematical modelling of the circuit. The reference current is taken from the load current by extracting dq, and the predicted current is obtained from the iteration of the voltage source converter (VSC) switching pattern. Each combination is compared with the reference current in the cost function to get the smallest error used as a power switching signal. Modelling was validated by using MATLAB Simulink. The simulation results prove a decrease in harmonics at a balanced load from 22.16% to 4.2% and at an unbalanced load, reducing the average harmonics to 4.74%. The simulation also decreases the load current imbalance in the distribution network. Reducing the current in the neutral wire from 62.01%-0.42% and 11.29-0.3 A.</span>

Application of Deep Learning Gated Recurrent Unit in Hybrid Shunt Active Power Filter for Power Quality Enhancement

This research work aims at providing power quality improvement for the nonlinear load to improve the system performance indices by eliminating maximum total harmonic distortion (THD) and reducing neutral wire current. The idea is to integrate a shunt hybrid active power filter (SHAPF) with the system using machine learning control techniques. The system proposed has been evaluated under an artificial neural network (ANN), gated recurrent unit, and long short-term memory for the optimization of the SHAPF. The method is based on the detection of harmonic presence in the power system by testing and comparison of traditional pq0 theory and deep learning neural networks. The results obtained through the proposed methodology meet all the suggested international standards of THD. The results also satisfy the current removal from the neutral wire and deal efficiently with minor DC voltage variations occurring in the voltage-regulating current. The proposed algorithms have been evaluated on the performance indices of accuracy and computational complexities, which show effective results in terms of 99% accuracy and computational complexities. deep learning-based findings are compared based on their root-mean-square error (RMSE) and loss function. The proposed system can be applied for domestic and industrial load conditions in a four-wire three-phase power distribution system for harmonic mitigation.

PV/WT Integrated System Using the Gray Wolf Optimization Technique for Power Quality Improvement

This paper presents the integration of renewable energy sources such as photovoltaics, wind, and batteries to the grid. The hybrid shunt active power filter (HSHAPF) is optimized with the Gray wolf optimization (GWO) and fractional order proportional integral controller (FOPI) for harmonic reduction under nonlinear and unbalanced load conditions. With the use of GWO, the parameters of FOPI are tuned, which effectively minimizes the harmonics. The proposed model has effectively compensated the total harmonic distortions when compared with without the filter and with the passive filter, the active power filter with a PI controller, and the GWO-FOPI-based controller. The performance of the proposed controller is tested under nonlinear and unbalanced conditions. The parameters of the FOPI controller are better tuned with the GWO technique. The comparative results reflect the best results of GWO-FOPI-based HSHAPF. The suggested controller is built in the MATLAB/Simulink Platform.

Adaptive Self-Tuned Current Controller Design for an LCL-Filtered LC-Tuned Single-Phase Shunt Hybrid Active Power Filter

This paper proposes an adaptive self-tuned current controller design for an LCL-filtered LC-tuned single-phase shunt hybrid active power filter (HAPF), which offers adaptability and flexibility of the control system to filter parameters changes. System modelling and online identification of parameters are presented. Then, a systematic self-tuned controller (STC) design is proposed to calculate the controller parameters and obtain the final control law adaptively. The exact HAPF parameters design is described and the overall closed-loop stability evaluation with considering digital control delay is discussed in this paper. To confirm the theoretical achievements, simulations and experimental tests on a real prototype system are performed. The results are in good accordance and demonstrate the effectiveness and superior performance of the suggested control technique. Furthermore, a comprehensive comparison between the proposed control technique and other controllers is provided to show the superiority of the proposed system from different aspects.

A pot line rectiformer scheme with hybrid-shunt active power filter

Passive harmonic filters (PHF) are commonly used in conventional potline rectifier transformers (Rectiformer) schemes of aluminum smelters to improve the power quality and reduce harmonic distortions to an acceptable level. However, changes in operating conditions and system configuration affect the performance capability of PHF in attenuating harmonics. In this paper, a Rectiformer scheme with hybrid-shunt active power filter (SAPF) is used instead of PHF and compared with the other commonly applied schemes in aluminum smelter in terms of harmonic attenuation capability. The SAPF potline Rectiformer scheme and other schemes are modeled and simulated using MATLAB/Simulink. A control strategy suitable for potline load behavior is furnished in this paper for SAPF. The simulation results reveal the performance superiority of the proposed SAPF as compared to the conventional and ALBA pot line (PL) 6 schemes.

Application of optimisation technique in PV integrated multilevel inverter for power quality improvement

In recent days multilevel inverters (MI) have played an essential role in photovoltaic (PV) integrated supply systems. MI has high efficiency and is more robust compared to the traditional two-level inverter. This paper presents a modular cascaded multilevel inverters (MCMI)-based hybrid shunt active power filter (HSAPF) with PV integrated for power quality (PQ) improvement in three-phase utility systems. The main aim is to deliver the PV system's active power and reduce the current harmonics by injecting the compensation current at the point of intersection (POI). The main contributions in this work presents an optimization based approach called the predator-prey based fire-fly optimization (PPFO) for reducing the total harmonic distortions (THD) and, the Adaptive Perturb and Observe–Fuzzy (APOF) is developed for tracking the maximum power. The effectiveness of the PPFO is tested with other methods like particle swarm optimization (PSO) and fire-fly optimization (FO). The proposed technique is performed using MATLAB/ Simulink tool under different supply conditions.

Hardware-in-the-Loop Implementation and Performance Evaluation of Three-Phase Hybrid Shunt Active Power Filter for Power Quality Improvement

The excessive use of nonlinear load causes electric current harmonics that ultimately downgrades the electrical power quality. If a failure exists due to internal integration of a power system in any one of the internal networks, it causes uncomplimentary consequences to the entire power system’s performance. This paper proposed a hybrid shunt active harmonic power filter (HSAHPF) design to reduce harmonic pollution. A digital controller HIL simulator has been modeled using a three-phase voltage source inverter to test the efficiency of HSAHPF and the performance of control algorithms. Moreover, the instantaneous active and reactive current theory (Id − Iq) and instantaneous active and reactive power theory (Pq0) control algorithms are implemented for the reference current generation in HSAHPF, resulting in reduced harmonic distortions, power factor improvement for a balanced nonlinear load. The control algorithms are further employed in Arduino MEGA to keep the factor of cost-effectiveness. The simulation of the proposed design has been developed in Simulink. The validation and testing of HSAHPF using controller HIL simulation prove the control algorithms’ ability to run in a portable embedded device. The statistical analysis of the proposed system response provides a minimum total harmonic distortion (THD) of 2.38 from 31.74 that lies in IEEE 519-1992 harmonic standards with an improved stability time of 0.04 s. The experimental verification and provided results of the HIL approach validate the proposed design. Significant mitigation of harmonics can be observed, consequently enhancing the power quality with power factor near unity.

Control Strategy of 1 kV Hybrid Active Power Filter for Mining Applications

The paper presents a shunt hybrid active power filter for 1 kV mining applications in configuration with a single-tuned passive filter. The focus is on the method of controlling the filter, with particular emphasis on the influence of network voltage distortion and time delays in control on the effectiveness of harmonic reduction, which is one of the most important aspect of power quality. The low-power loss configuration of a hybrid filter with SiC transistors is shown, as well as the control algorithm which limits the influence of voltage distortion. Theoretical considerations are verified by results obtained from simulations and tests of the hybrid active power filter prototype.

Neural Networks Based Shunt Hybrid Active Power Filter for Harmonic Elimination

The growing use of nonlinear devices is introducing harmonics in power system networks that result in distortion of current and voltage signals causing damage to power distribution systems. Therefore, in power systems, the elimination of harmonics is of great significance. This paper presents an efficient techno-economical approach to suppress harmonics and improve the power factor in power distribution networks using Shunt Hybrid Active Power Filters (SHAPF) based on neural network algorithms like Artificial Neural Network (ANN), Adaptive Neuro-Fuzzy Inference System (ANFIS), and Recurrent Neural Network (RNN). The objective of the proposed algorithms for SHAPF is to enhance system performance by reducing Total Harmonic Distortion (THD). In our filter design approach, we tested and compared conventional pq0 theory and neural networks to detect the harmonics present in the power system. Moreover, for the regulation of DC supply to the inverter of the SHAPF, the conventional PI controller and neural networks-based controllers are used and compared. The applicability of the proposed filter is tested for three different nonlinear load cases. The simulation results show that the neural networks-based filter control techniques satisfy all international standards with minimum current THD, neutral wire current elimination, and small DC voltage fluctuations for voltage regulation current. Furthermore, the three neural network architectures are tested and compared based on accuracy and computational complexity, with RNN outperforming the rest.

Performance of Hybrid Filter in a Microgrid Integrated Power System Network Using Wavelet Techniques

Nowadays, the application of distributed energy sources (DES) has been extensively employed to serve the power system by supplying the power into the grid and improving the power quality (PQ). Therefore, DES is one solution that can efficiently overcome the energy crisis and climate change problems. The DES, such as solar photovoltaic (PV), wind turbine (WT), and battery energy storage systems (BESS), are incorporated to form the microgrid (MG), which are interfaced with the power system. However, interfacing MG to the power system is undoubtedly a big challenge. Therefore, more focus is required on the control strategy to control the MG with the power system. To address the PQ problems, a controlled MG integrated with a hybrid shunt active power filter (HSAPF) is provided in this work. For controlling the MG integrated HSAPF, different control strategies are applied. In this work, a learning-based incremental conductance (LINC) technique is used as a maximum power point tracking (MPPT) for tracking the maximum power in PV and WT. The voltage source inverter (VSI) of HSAPF is controlled using a wavelet-based technique with a synchronous reference frame (SRF). The main focus is to improve the PQ by compensating the harmonics and regulating the reactive power in both grid-interactive and islanded condition and also supply continuous and adequate power to the non-linear load. The power system model has been developed with MATLAB/Simulink tool, which shows the efficiency of the proposed method. The results obtained have been satisfactorily under various operating conditions and can be validated further using the real-time dSPACE.

Design of shunt hybrid active power filter for compensating harmonic currents and reactive power

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.

Harmonics mitigation in hybrid shunt active power filter connected renewable energy source using an intelligent controller

This paper proposes an intelligent technique-based optimal controller for harmonics mitigation to maintain the power quality in renewable energy source (RES)-based distribution systems. The proposed intelligent technique is the joint execution of both the fractional-order proportional integral controller and moth-flame optimization with random decision forest. In the proposed approach, moth-flame optimization optimizes the dataset of fundamental and harmonic loop parameters such as terminal voltage and direct current voltage present in the hybrid shunt active power filter. The dataset is generated based on the linear and nonlinear load variation and parameter variation of the renewable energy sources, subject to the minimum error objective function. Based on the accomplished dataset, random decision forest accurately predicts the parameters and produces optimized control signals. The proposed technique guarantees the system with less complexity for the harmonics mitigation of the power quality event and hence the accuracy of the system is raised. Then, the proposed model is executed in the Matrix Laboratory/Simulink working platform and the execution is assessed with the existing techniques. The simulation analysis of the proposed approach is tested using the six test cases with various combinations of nonlinear loads. In all the test cases, the performance of various system parameters, such as source current with and without filter, source voltage, hybrid shunt active power filter current, load current and voltage, is analysed. Furthermore, the total harmonic distortion at different load ratings is also examined.

Adaptive fuzzy controlled hybrid shunt active power filter for power quality enhancement

A novel switching pulse generation methodology based on adaptive fuzzy hysteresis current controlled hybrid shunt active power filter (A-F-HCC-HSAPF) is presented in this paper for compensating reactive power and harmonics in distribution network. The harmonic problems are mainly evolved because of extensive use of nonlinear loads in industry and domestic sectors. There are some adverse effects of harmonics such as: malfunctioning of sensitive equipment, resonance issues, conductors heating, power losses and reduced efficiency in distribution system. To mitigate harmonics issues passive, filters are used but when the harmonic component increases the design of passive filters is complex and becomes bulky. With the advancement in power electronic, the active power filter has been designed. Generally, the rating of the active filter is very high for some applications; hence hybrid shunt active power filter (HSAPF) is proposed by low-rated shunt active power filter (SAPF) and low-cost shunt passive filter. Proportional-integral or fuzzy logic controller is used to estimate the reference current and to regulate the dc capacitor voltage. To generate the switching pulse for the voltage source inverter of the SAPF, a novel adaptive fuzzy hysteresis current controller (A-F-HCC) is adopted. The performance of the proposed A-F-HCC-HSAPF is investigated during steady-state and transient conditions using MATLAB/Simulink and real-time environments.

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.

Power Quality Improvement in Grid from Wind Turbine by using Shunt Hybrid Active Filter

This paper provides Frame D-Q Synchronous Reference Frame (SRF) current manipulate technique for generating a reference present day that's required for 3-phase four-twine electric hybrid shunt hybrid active power filter (SHAPF) to resolve the hassle of harmonics in the power device community. Here, the passive factors SHAPF has beenused for reactive strength reimbursement and to eliminate the decrease order harmonics and lively parts have been used for the higher harmonics. A modified phase lock loop (PLL) has been used to address multiple frequency elements of non-perfect voltage. All simulations to attain the purpose that has been achieved in the MATLAB / SIMULINK for best conditions and unbalanced electrical voltage. From the simulation results have shown that the implementation of the proposed D-Q SRF SHAPF based THD result in a reduction in community electricity systems in both the balanced and unbalanced situations.