Passive Filter Design Research Articles

Optimal passive LCL filter design for grid-connected converters in weak grids

In an era characterized by the increasing integration of renewable energy sources into the power grid, the stability and resilience of the grid have become paramount, especially in areas with weak grid infrastructure. One effective approach to mitigate the adverse effects of grid disturbances and harmonics is passive LCL (inductor-capacitor-inductor) filters. However, designing these filters for optimal performance under varying conditions remains challenging. This research paper presents an effective approach to addressing this challenge by utilizing the power of evolutionary algorithms, specifically Multi-Objective Particle Swarm Optimization (MOPSO) and Multi-Objective Genetic Algorithm (MOGA), to design optimal passive LCL filters for weak grid environments. The proposed method aims to enhance grid resilience by optimizing the filter parameters to consider a weak grid's unique characteristics and uncertainties. Minimizing the resonance frequency has succeeded in achieving power quality and stability improvements related to changes in grid impedance. The proposed approach achieves power quality and stability improvements related to changes in grid impedance and dealing with fragile conditions, which is the main scope of this paper.© 2017 Elsevier Inc. All rights reserved.

Optimal design of passive filters for minimization of harmonic distortion in industrial power system applications

Optimal design of passive filters for minimization of harmonic distortion in industrial power system applications

Passive bandpass filters for modern microwave communication systems

Background. Bandpass filters are an integral part of any radio engineering systems and modern communication systems. Research and development of new passive components is due to growing need for such elements for modernization and creation of new modern communication systems.
 Aim. A brief overview of passive bandpass filters. Their classification according to the type of implementation is given.
 Methods. Results of experimental research and design of different passive bandpass filters are considered.
 Results. Lumped elements filters, microstrip filters, filters on high-temperature superconductor films, filter on dielectric resonators, surface acoustic wave filters, bulk acoustic wave filters are considered. At a qualitative level, the main advantages and disadvantages are considered from point of view of electrical parameters and size indicators. Examples of topological and constructive implementation are given.
 Conclusion. The passive bandpass filters considered in the paper make it possible to implement frequency selection devices at operating frequencies up to 6 GHz and higher, taking into account modern system trends and requirements for devices of this type.

Design of passive filter based on magnetic integrated technology for single‐phase grid‐connected inverter

AbstractIn response to the need for smaller and lighter power supply equipment, there has been a push towards higher power density in current power electronic converters. This development aligns well with the requirements of photovoltaic grid‐connected inverters. Among various passive filters utilized in these inverters, the LCL filter stands out as a popular choice. Nevertheless, it should be noted that traditional LCL filters have limited core utilization and exhibit significant redundancy. In view of the above problems, this paper proposes a magnetic integrated passive filter based on ripple transfer technology and carries out volume optimization design. Compared to the conventional LCL filter, the magnetic integrated passive filter offers a reduction in size and weight while preserving its capability to ripples attenuate. Finally, a laboratory prototype with a rated power of 2 kW is built to verify the effectiveness of the proposed magnetic integrated passive filter.

Conservative Power Theory (CPT): A New Approach to the Tuned Passive Filter Design

The study of the effect of the harmonic distortions and the power factor in a system with presence of nonlinear loads becomes crucial to the quality of electrical energy. Based on this problem, this article uses the Conservative Power Theory to evaluate parameters associated to product quality, aiming to obtain subsidies for the design of tuned passive filters focused on the reduction of harmonic distortion indexes associated with voltage and current, in addition to contribute to the reactive compensation of the electrical system under research.

Bi-Level damped double-tuned harmonic passive filters design: Multi-criteria decision-making analysis

Bi-Level damped double-tuned harmonic passive filters design: Multi-criteria decision-making analysis

Selective Virtual Synthetic Vector Embedding for Full-Range Current Harmonic Suppression of the DC Collector

With the rapid development of rene wable energy (e.g., wind and photovoltaic energy) and energy storage, the dc collector has become an effective conversion link of distributed energy access to medium-voltage power distribution grids. However, considering the inconsistency of dc voltage and the duty cycle of each submodule, the traditional carrier phase-shifting modulation is difficult to achieve the excellent harmonic characteristic in the dc collector, thereby introducing difficulties in the design of passive filters. To solve this problem, this article proposes a selective virtual synthetic vector embedding algorithm to realize full-range current harmonic suppression in the dc collector system. In this scheme, the switching voltage vectors outputted by each submodule are sorted, and the voltage vectors are selectively extracted and synthesized to calculate the embedded virtual voltage vector. Afterward, the voltage vector of each submodule is rotated and calculated online from the perspective of space geometry, and the optimal carrier phase combination in variable-angle carrier phase-shift modulation is obtained. Finally, the experimental results show that the proposed control algorithm can not only be used in the dc collector with any number of modules but also achieve fast and effective harmonic suppression in the whole operating range.

Optimal Design Method of High Voltage DC Power Supply EMI Filter Considering Source Impedance of Motor Controller for Electric Vehicle

Passive filters are often used for electromagnetic interference (EMI) suppression on the high voltage (HV) DC side of motor drive systems due to their simple structure and large noise suppression. However, the traditional passive filter design method takes less consideration of the change of the system source impedance, which will lead to almost no insertion loss in some frequency bands or an over-design of the filter. Based on the onboard working conditions of high-voltage and high-current, this article adopts the dual current probe method to obtain the source impedance of the system when it is working, and proposes a filter multi-objective optimization design method based on the genetic algorithm (GA). This method automatically selects the optimal topology of the filter and related component parameters according to the source impedance and load impedance, avoiding the filter resonance phenomenon and over-design problems caused by not considering source impedance. The experimental results show that conducted interference voltage and current of motor drive system with filter designed by the proposed method can pass CISPR25-2016rd level 3.

정현파 주입 방안 적용에 따른 HAPF용 패시브 필터 설계 방안의 역률 보상 정확성 개선

This paper proposes a method to compensate for the power factor error existing in the passive filter design method for HAPF by applying the sinusoidal wave injection method to the LC design method of the passive filter for HAPF. As the LC design method of the passive filter for HAPF assumes that is 1[p.u], it is necessary to completely compensate the harmonics included in the system to accurately compensate the power factor. This is a result of assuming an ideal case, and in practical terms, harmonics cannot be completely eliminated. Therefore, since is not 1[p.u], an error may occur in reactive power compensation. Accordingly, in this paper, we propose a method to reduce the power factor error by applying the sinusoidal injection method based on the default value used in the LC design method of the passive filter for HAPF for MI. The power factor error that appears when the sinusoidal wave injection method is applied to the LC design method of the passive filter for HAPF was precisely compared and analyzed, and the error and effect were analyzed through simulation. As a result, it was possible to see the result of reducing the error from 0.296 [%], which is the power factor error of the passive design method for HAPF, to about 0.04 [%] by applying the sinusoidal injection method.

Comparative analysis of optimal damped and undamped passive filters using MIDACO-solver

Harmonic pollution is one of the challenging problems facing power networks recently due to the widespread non-linear loads and inverter-based renewables. In this regard, this work presents the optimal design of damped and undamped passive filters using a solver called Mixed-Integer Distributed Ant Colony Optimisation (MIDACO). This solver is employed to obtain an optimal design strategy for single-tuned passive power filters by investigating three primary criteria – minimisation of active power losses of the Thevenin’s resistor, maximisation of the true power factor, and maximisation of the transmission efficiency. Several constrictions associated with the designed filters have been considered, in which the global maximum or minimum criterion was attained by retaining the quality factors of the designed filters within a particular range, damping harmonic resonance, achieving a permissible range of the power factor, limiting voltage harmonic distortion by complying with IEEE Std. 519–2014 restrictions. Besides, the performance limits of capacitors operating in distorted systems have been met while complying with IEEE Std. 18–2012. Further, the results obtained using the MIDACO solver in four different case studies are compared to those obtained using particle swarm optimisation and genetic algorithm. In addition, this work depicts the damping resistor of the inductance in the single-tuned filters. The benefits and drawbacks of damping over an undamped filter are discussed. Finally, the results validate the effectiveness of the MIDACO solver employed in this paper.

Increasing-Dimension Evolution: Make the evolutionary design of passive filters more efficient

Evolutionary circuit design is a promising way to achieve the automatic synthesis of analog circuits, and passive filters are essential circuits that must be considered. For now, in the evolutionary design of passive filters, the size control of filters under practical difficulty is still an important issue to be studied. This paper proposed a search strategy called Increasing-Dimension Evolution (IDE). The strategy introduces the concepts of exon and intron to control gene expression levels in evolutionary search. Through this strategy, even if the length of the chromosome is fixed, the search engine can effectively search up multiple design spaces and find a small circuit size at low computing costs. We built an effective evolutionary filter design model using the IDE strategy. Experimental results show that the proposed strategy can obtain filter sizes comparable to advanced conventional design methods for several passive filter design tasks with practical difficulties. In addition, the strategy makes the search engine more effective in a given complex task, and this task is difficult to be directly solved using conventional design methods.

Passive filter design research in hybrid active filter design

There's an urgent need to apply active filter in HVDC project. The control strategy of active filter that imitating a resistor is effective to restrain the harmonic voltage. There are two strategies combined used: voltage feedback strategy and impedance offset strategy, which make the impedance of hybrid active filter extremely low at aim frequencies. The passive filter in hybrid active filter will influence the impedance finally reached. In this research, we designed several topologies of passive filter to design corresponding active filter. We calculated the impedance of each design, analysed the stability, simulate the filter performance and calculated the IGBT modules consumption. Besides, we calculated the equipment stable and transient rating voltage and current stress. Finally we concluded the suitable passive filter topology for hybrid active filter design.

Optimal Selection of Reactive Power For Single Tuned Passive Filter Based on Curve Fitting Technique

This research presents the Optimal Reactive Power (Qc) selection for a single-tuned passive filter. DC drives are very popular in the industrial zone due to their high performance, flexibility, easy control, and low cost. DC drives operate by giving supply from an AC utility and AC to DC can be converted using the AC-DC converter. But this conversion introduces harmonics in the input supply current that affect the performance of the DC drive and also cause serious problems for the overall power quality of the system. Many researchers are searching for the appropriate solutions to mitigate this cause. A passive filter is one solution to minimize or avoid harmonics from entering the electrical system. The key aspect of the passive filter design has been a difficult task. The parameters of the passive filter largely depends upon selecting the suitable value of reactive power (Qc). In this paper, the Simulink model of an AC-DC converter based on a separately excited dc motor is used as an industrial load, and a curve fitting technique has been used to select the optimal value of reactive power (Qc) for the passive filter. The simulation results and analysis show that optimal selection of reactive power for single tuned passive filter using the proposed technique is very effective by taking international standards limits for harmonic distortion.

Harmonic mitigation of AC electric railway power feeding system by using single-tuned passive filters

Harmonic is an important factor affecting the quality of the power transmission system. caused by non-linear loads and power conversion devices. In this research, several train simulation samples of the city line Airport Rail Link (ARL) electric train were used to simulate the effects of harmonics on the power electric substation (ESS) by calculating the Total Harmonic Distortion of voltage (THDv) and current (THDi). Then compared with IEEE519-2014 standards to indicate the quality of power found that THDi 35th–50th exceeds the standard. In addition, the comparison of the harmonic reduction effect of the sample train from the single tuned passive filter designs of 3rd, 5th, 7th, and 11th showed that the 11th filter was able to keep the THD within the standard.

Intelligent Tuned Hybrid Power Filter with Fuzzy-PI Control

With the growing impact of power regulators, machines, and other power electronic devices on the quality of utility electric service, harmonics has recently emerged as a major research topic in the area of power quality and energy consumption. In this work, a fuzzy intelligent inductor–capacitor–inductor hybrid power filter is designed to reduce harmonics in the distribution line. The shunt active power filter and passive filter design and consideration have been improved. Since the nature of proportional integral control is only efficient with linear variations and the real condition of the distribution system is always varying nonlinearly, to create a minimum steady error, fuzzy-tuned proportional integral control is designed to intelligently consider the input changes and revise the decision rules using fuzzy reasoning. The content of the harmonic current with respect to the varying load is momentarily commutated. Thus, using Clarke’s transformation, the errors are summed with instantaneous power that is converted to a compensation current with the hysteresis band monitored pulse generator. The output current would turn off and on the IGBT inverter’s switches, supplying the current to reject the harmonics. The overall work was tested using MATLAB/SIMULINK® and was effective in canceling harmonics.

Passive Harmonic Filter Design Considering Voltage Sag Performance - Applicable to Large Industries

Nowadays, nonlinear loads such as load commutated inverter (LCI) drives are being used by industrial sector throughout the world. However, despite the LCI drive uses low-cost thyristors and their corresponding controllers, which have high efficiency and low manufacturing cost, there are concerns regarding the use of LCI drives which are two-fold: (i) they generate harmonics and (ii) they are sensitive to voltage sags occurring at their PCC. In the literature, passive harmonic filters have been suggested to address the former concern and therefore various filter designing techniques have been introduced. However, the need to elaborate a cost-effective filter to address both concerns regarding LCI drive operation has been neglected. Therefore, this paper presents an innovative approach for designing passive filters which can decrease the harmonic distortions generated by LCI drives while ensuring more reliable annual operation of these equipment. Besides, other aspects of passive filter designing, such as eliminating detuning effects, resonance elimination and harmonic loading of capacitors, have been taken into account to provide a general and practical filter designing approach for real industrial applications. In order to evaluate the innovative proposed approach, a passive filter is designed for LCI drive used in an Iranian large copper mine company.

A novel design of fourth-order harmonic passive filters for total demand distortion minimization using crow spiral-based search algorithm

Mathematical design of a new fourth-order harmonic passive filter is presented and its optimal strategy is proposed with regards to various design scenarios. The considered objective function is total demand distortion minimization of the supply current. The crow spiral-based search algorithm (CSSA) is applied to solve the design problem formulated. This CSSA relies on a spiral search mechanism that improves the convergence and balances the exploration and exploitation abilities of the conventional crow search algorithm. Various power quality indices are taken into consideration like the individual and total harmonic voltage distortion values, individual and total current harmonic distortion values, active power loss, actual and displacement power factor percentages, and resonance damping capabilities. These indices were handled as non-linear constraints in the design. Additionally, a comparative investigation of the different damped filters is presented to assess the planned filter performance. The results obtained confirm the success of the filter design proposed in this paper.

Optimal Design of Passive Power Filters Using the MRFO Algorithm and a Practical Harmonic Analysis Approach including Uncertainties in Distribution Networks

The design of Passive Power Filters (PPFs) has been widely acknowledged as an optimization problem. This paper addresses the PPF parameters design problem using the novel Manta Ray Foraging Optimization (MRFO) algorithm. Moreover, an analytical method based on Monte Carlo Simulation (MCS) is proposed to investigate the harmonic performance of such an optimally designed PPF with variations in power networks. The MRFO algorithm has shown a superior solution-finding ability, but a relatively higher computational effort in comparison with other recently proposed algorithms. The harmonic performance of the optimal PPF solution with uncertainties was analyzed using the proposed method. The results imply that the optimally designed PPF can effectively attenuate the high-order harmonics and improved the system performance parameters over different operating conditions to continually comply with the standard limits. The proposed MCS method showed that the optimally designed PPF reduced the voltage and current distortions by roughly 54% and 30%, respectively, and improved the network hosting capacity by 10% for the worst-case scenario.

Minimization of power losses in passive power filters

THE PURPOSE. Broadband passive filters (BBF) are an effective measure to mitigate harmonic resonance in power systems with nonlinear harmonic producing loads. The disadvantage of simple second-order broadband filters are pure selectivity and excessive fundamental frequency losses. This is especially evident in devices designed for low-order harmonics mitigation. This paper presents new broadband filter configurations with superior performances and low fundamental frequency losses.METHODS. A general method of broadband passive filter design is considered. The filter has the form of single-loaded ladder LC-two-port. Conditions of minimal fundamental frequency loss of the filer are determined.RESULTS. This paper presents new broadband filter configurations with superior damping performances and low fundamental frequency losses. Different broadband filter configurations are compared. The results show that 3-5 order broadband ladder filters have better filtering performance and lower power loss than traditional C-type filters.CONCLUSION. The proposed broadband filters can be used for industrial power systems with powerful nonlinear loads. This will normalize the power quality and at the same time improve the energy efficiency of compensating devices.

Optimal design of passive power filter for enhancing the harmonic-constrained hosting capacity of renewable DG systems

This paper investigates the application of a passive harmonic filtering to improve the harmonic-constrained hosting capacity (HCHC) of renewable distributed generation (DG) systems in harmonically polluted distribution systems. Concurrently, the optimal parameters of a C-type passive filter (CTPF) and the rating of the DG system are set. The optimum HC of the distorted grid for DG is achieved while reducing total filter cost (FC) to a minimum. Using the newly suggested multi-objective Pareto-based bat algorithm (pb-MOBA), a best-of-breed solution is obtained. The formulated problem of multi-objective optimization (MOO) is dealt with under a number of system performance indices (PIs) constraints such as individual as well as total harmonic distortion (THD) in the line current and the point of common coupling's (PCC) voltage, distribution line ampacity under harmonic current overloading, steady-state voltage profile, load power factor (PF), and so on and a handful that is linked to the passive power filter (PPF) itself. The Pareto optimal front is produced using the MOBA extension, and the trade-off between the objectives is examined. The efficiency and accuracy of pb-MOBA, in dealing with the designated MOO problem, is confirmed by making a comparison of the acquired solution and three computed PIs viz. diversity metric (DM), generational distance (GD), and convergence metric (CM) with those achieved by Multi-objective Pareto-based PSO (pb-MOPSO), Non-dominated Sorting Genetic Algorithm (NSGA).