Showing papers on "Electronic filter published in 2017"
TL;DR: In this article, an alternative impedance model is proposed for the single-loop current control, and damping injection based on the discrete derivative controller is proposed to enhance the passivity of individual converters and thereby stabilizing the paralleled converters.
Abstract: This paper addresses the harmonic stability resulting from the current-control interactions of the multiparalleled, LCL -filtered voltage-source converters. First, an alternative impedance model is proposed for the single-loop current control. The control output admittance of the converter is decomposed into a passive filter output admittance in series with an active admittance, which is dependent on the current controller and the time delay. The frequency-domain passivity theory is then applied to the active admittance for system stability analysis. It reveals that the stability region of the single-loop grid current control is not only dependent on the time delay, but affected also by the resonance frequency of the converter-side filter inductor and filter capacitor. Further on, the damping injection based on the discrete derivative controller is proposed to enhance the passivity of individual converters and thereby stabilizing the paralleled converters. Finally, simulation studies and laboratory tests validate the effectiveness of theoretical analysis and controller design.
160 citations
TL;DR: In this paper, a trap-LCL filter with its parallel resonant LC-trap located on the converter side, named as LT-C - L filter, is presented. And the model and analysis presented in this paper show that the LS-L filter can be the most promising trap filter due to its advantages such as high roll-off rate, robustness against parametric variations of grid impedance and passive damper, satisfactory harmonic attenuation at the switching frequency, reduction of converter current total-harmonic-distortion, and flexible design of filter components through magnetic integration.
Abstract: High-frequency current harmonics injected into the point of common coupling, mainly at the switching frequency and its multiples introduced by the modulation of grid-connected converters, should be limited to comply with grid codes. This requirement can be satisfied by using trap filters with LC -traps tuned at the switching frequency and its multiples in replacement of conventional L filters. However, all existing trap filters are subject to certain problems, e.g., sensitivity to grid impedance variation and decreased high-frequency roll-off rate. In view of this, this paper presents a trap- LCL filter with its parallel resonant LC -trap located on the converter side, named as LT-C - L filter. The modeling and analysis presented in this paper show that the LT-C - L filter can be the most promising trap filter due to its advantages such as high roll-off rate, robustness against parametric variations of grid impedance and passive damper, satisfactory harmonic attenuation at the switching frequency, reduction of converter current total-harmonic-distortion, and flexible design of filter components through magnetic integration. A single-phase ac/dc grid-connected converter prototype has been built and tested in the laboratory, and experimental results are presented to verify the superiority of the proposed filter.
68 citations
TL;DR: In this paper, the authors proposed an integrated high-order LCL filter for grid-connected power conversion systems, where the converter side inductor and the grid-side inductor are integrated together and their coupling coefficient is intentionally minimized, which is equivalent to inserting an additional inductor into the filter capacitor branch loop.
Abstract: High-order passive filters, such as the well-known LCL filters, are normally employed in the grid-connected power conversion systems to effectively attenuate the switching frequency harmonic introduced by the modulation of power converters. Although much more compact than the conventional single-inductor L filters, such passive filters are still bulky and expensive when compared with their active counterparts, e.g., the semiconductor switches. In order to improve the system power density and reduce its cost, the magnetic integration technique has been widely adopted so that the discrete inductors of passive filters are replaced by the integrated inductor, resulting in smaller magnetic cores and, therefore, the decreased volumes of passive filters. For conventional magnetic integrated LCL filters, the converter-side inductor and the grid-side inductor are integrated together and their coupling coefficient is intentionally minimized. In this letter, this coupling coefficient is fully utilized and properly designed, and the resulting coupling effect is equivalent to inserting an additional inductor into the filter capacitor branch loop. The integrated inductor and the filter capacitor can form an integrated LLCL filter, which exhibits the advantages of both the LLCL filter and magnetic integration, e.g., enhanced harmonic attenuation, reduced filter inductances, and system volume without adding the extra trap inductor. Finally, experimental results obtained from a single-phase grid-connected voltage-source converter interfaced by the proposed integrated filter are presented to validate its effectiveness.
51 citations
TL;DR: A novel filter called the damped high-pass filter is proposed, which does not cause resonance at the noncharacteristic harmonic frequencies and is no longer needed, resulting in significant cost and space savings for the multipulse systems.
Abstract: Multipulse rectifier systems are commonly used to reduce harmonic emission. However, they still require the installation of noncharacteristic harmonic filters to prevent harmful resonance between its high-pass filter and the system impedance. The advantage of a multipulse configuration-very low noncharacteristic harmonic emission-is, therefore, not fully utilized. In view of this shortcoming, a novel filter called the damped high-pass filter is proposed. The filter does not cause resonance at the noncharacteristic harmonic frequencies. As a result, traditional noncharacteristic 5th and 7th harmonic filters are no longer needed, resulting in significant cost and space savings for the multipulse systems. The core idea behind this filter is a frequency-dependent resistor block that provides high damping at the noncharacteristic harmonic frequencies. The design procedure for the proposed filter is presented. Performance and usefulness of the new filtering scheme has been demonstrated through comparative studies on two actual industry cases.
50 citations
TL;DR: In this article, the capacitance placement and passive filter placement problems are considered as a unified problem in which a set of passive compensators (capacitors and/or tuned filters) that allow to obtain the maximum annual saving in cost and maximum improvement of the power quality of the circuit are determined.
46 citations
TL;DR: In this article, the authors compared the performance of a fourth-order LC low-pass filter with a second-order filter with planar spiral inductors and on-chip capacitors.
Abstract: Fully integrated buck converters are typically operated with a second-order LC low-pass filter and a switching frequency beyond 100 MHz. The motivation for such design choices is to reduce the size of passive components in the LC low-pass filter required for small output voltage ripple. However, in a buck converter with on-chip planar spiral inductors, a fourth-order filter can deliver better performance characteristics without area penalty. This paper presents a comparative study of a fourth-order LC low-pass filter versus a second-order LC low-pass filter with on-chip planar spiral inductors and on-chip capacitors. A fully integrated buck converter is then designed with a quasi-V
2
controller to demonstrate the benefits of a fourth-order LC low-pass filter. The prototype chip, which is implemented in a 65-nm CMOS process, produces a nominal voltage of 0.7 V from a 1-V supply. The fourth-order LC low-pass filter uses a total inductance of 1.8 nH and a total capacitance of 4 nF. Measurement results demonstrate fast transient response on the order of nanoseconds. A peak efficiency of 76.1% is achieved, and the output voltage ripple is kept below 15 mV over the entire range of load current from 40 to 180 mA.
32 citations
TL;DR: Experimental results show that the proposed sensorless start-up strategy can realize a low-current start- up and a hysteresis control strategy is proposed against the load disturbance in the start-ups.
Abstract: This paper focuses on the start-up strategy of a high-speed 100-kW brushless dc motor with small inductance using a voltage comparator. This paper includes three key technique contributions: 1) determining zero-speed positioning, 2) removing high-frequency disturbances, and 3) optimizing the controller parameters. The sensorless low-current start-up strategy is based on an amplification circuit: a low-pass filter circuit and a signal modulate circuit. The amplification circuit is used to amplify the amplitude of back electromotive force for detecting the rotor position at low speed, the low-pass filter circuit is used to remove high-frequency disturbances, and the signal modulate circuit is used to obtain the rotor position signal. A hysteresis control strategy is proposed against the load disturbance in the start-up stage. Experimental results show that the proposed sensorless start-up strategy can realize a low-current start-up.
29 citations
TL;DR: In this paper, the authors proposed two new power filters and their design method to further mitigate the bearing currents, and the theoretical analysis and the design method are introduced in detail, and experimental results are in good agreement with theoretical analysis.
Abstract: High-frequency pulse width modulation (PWM) in inverter-fed induction motor drive systems is widely used in industrial applications because of their flexible speed control and energy savings. However, high d v /d t PWM pulses induce overvoltage spikes on the motor via long cable. Such phenomenon would cause serious deterioration of the motor and cable. A passive overvoltage suppression technique of low-loss “RL-plus-C” filter was proposed recently. It has not only some merits of simple structure, low cost, and good robustness, but also a significant merit of low power dissipation. In order to further mitigate the bearing currents, this paper proposes two new power filters and their design method. The theoretical analysis and the design method are introduced in detail. Experimental results are in good agreement with the theoretical analysis.
27 citations
TL;DR: In this paper, a hybrid passive filter configuration for PWM rectifiers instead of existing filters was proposed, which successfully compensates current and voltage harmonics, and improves total harmonic distortion and true power factor.
Abstract: Wind energy conversion systems (WECS) which consist of wind turbines with permanent magnet synchronous generator (PMSG) and full-power converters have become widespread in the field of renewable power systems. Generally, conventional diode bridge rectifiers have used to obtain a constant DC bus voltage from output of PMSG based wind generator. In recent years, together advanced power electronics technology, Pulse Width Modulation (PWM) rectifiers have used in WECS. PWM rectifiers are used in many applications thanks to their characteristics such as high power factor and low harmonic distortion. In general, L, LC and LCL-type filter configurations are used in these rectifiers. These filter configurations are not exactly compensate current and voltage harmonics. This study proposes a hybrid passive filter configuration for PWM rectifiers instead of existing filters. The performance of hybrid passive filter was tested via MATLAB/Simulink environment under various operational conditions and was compared with LCL filter structure. In addition, neuro-fuzzy controller (NFC) was preferred to increase the performance of PWM rectifier in DC bus voltage control against disturbances because of its robust and nonlinear structure. The study demonstrates that the hybrid passive filter configuration proposed in this study successfully compensates current and voltage harmonics, and improves total harmonic distortion and true power factor.
27 citations
TL;DR: This study presents a multiple harmonic elimination-based feedback controller for shunt hybrid active power filter to perform an effective harmonic compensation performance in a wide harmonic frequency band and the compensation performance is compared with conventional methods both theoretically and experimentally.
Abstract: This study presents a multiple harmonic elimination-based feedback controller for shunt hybrid active power filter (SHAPF) to perform an effective harmonic compensation performance in a wide harmonic frequency band. The conventional control methods presented for SHAPF cannot perform an adequate performance, because of the disturbances such as phase delays caused by controller methods and measurement circuitries, tolerances of passive filter components and supply voltage harmonics. In the proposed controller, the conventional feedback controller is improved by using supply side individual current harmonics which are extracted by the synchronous reference frame method. To prevent the performance degradation effects of disturbances, proportional-integral controllers are applied to each d
and q
components of individual current harmonics. The compensation performance of the proposed method is compared with conventional methods both theoretically and experimentally. The experimental results verify the advanced harmonic compensation performance of the proposed control method.
25 citations
TL;DR: In this article, an overview of different transformer-less single-phase grid-connected photovoltaic inverters with various filter circuits including immittance conversion topology for residential application is presented, compared, and evaluated against components used, size, cost, self life, losses, and efficiency.
Abstract: This article presents an overview of different transformer-less single-phase grid-connected photovoltaic inverters with various filter circuits including immittance conversion topology for residential application. Various inverter topologies are presented, compared, and evaluated against components used, size, cost, self life, losses, and efficiency. To find the suitable topology, a number of factors are considered in the design of inverter: 1) the number of buck and boost stages in cascade; 2) the type of synchronization to align the PV output with the grid; 3) whether the inverter will be designed using a minimalist component strategy; 4) elimination of Total Harmonic Distortion (THD) and 5) efficiency. After a rigorous analysis, some of the topologies are pointed out as the best candidates for either single or multiple photovoltaic (PV) module applications.
04 Jun 2017
TL;DR: In this paper, a switchable bulk acoustic wave (BAW) filter based on barium strontium titanate (Ba 0. 5 Sr 0.5 TiO 3 ) thin film bulk acoustic resonators (FBARs) is presented.
Abstract: A Low insertion loss (IL) 1.5 stage H'-network ladder type intrinsically switchable bulk acoustic wave (BAW) filter based on barium strontium titanate (Ba 0 . 5 Sr 0 . 5 TiO 3 ) thin film bulk acoustic resonators (FBARs) is presented. The filter is designed and fabricated based on switchable BST FBARs with Q m =300 and K t 2=6%. When a DC bias is applied to the FBARs, the switchable filter is in its ON state and provides an insertion loss of 2.25 dB with 3-dB bandwidth of 58 MHz at 2.08 GHz center frequency. The switchable BST filter presented in this paper provides the lowest IL as compared to the previously reported BST filters.
TL;DR: In this article, a hybrid active power filter (HAPF) with a Type-II current controller was proposed for compensation of harmonics, reactive power and also the unbalance caused by different linear and non-linear loads of an industrial power system.
Abstract: Industrial power system consists of several linear and non-linear loads. The proliferation of non-linear loads in power system causes the power system harmonics. Passive filters (PFs) are one of the ancient solutions to mitigate the harmonics. Some of the industrial power systems use PFs for harmonic compensation. Owing to dynamic load variation, the PFs are not the appropriate solution for harmonic compensation. To improve the system performance with existing PFs, this study presents the conservative power theory (CPT)-based hybrid active power filter (HAPF) with Type-II current controller for compensation of harmonics, reactive power and also the unbalance caused by different linear and non-linear loads of an industrial power system. In this system, the CPT is used as a harmonic reference generator and Type-II controller is designed for current control operation. The proposed HAPF overcomes the drawbacks of PFs and performs the compensation tasks effectively. The industrial power system with the proposed HAPF is modelled in MATLAB/Simulink environment and implemented in the real-time (RT) using OPAL-RT-based RT simulator. The RT results are in compliance with IEEE 519-2014 standard.
01 Oct 2017
TL;DR: An integrated optoelectronic Oscillator (IOEO) which combines the integrated technologies of photonics and electronics has been developed for the first time to integrate both the optical and electrical part on a single substrate.
Abstract: An integrated optoelectronic Oscillator (IOEO) which combines the integrated technologies of photonics and electronics has been developed. All of the necessary elements (for example, laser, photo-detector, electrical amplifier, electrical filter, etc.) have been assembled on a print circuit board (PCB) within size of 5∗6 cm. To the best of our knowledge, it is the first time to integrate both the optical part and electrical part on a single substrate. Finally, a stable microwave signal with the frequency of 7.3 GHz is obtained. The center oscillation frequency can be slightly tuned in 20 MHz bandwidth by strictly tuning the injection current. The phase noise is around −91dBc/Hz at 1MHz.
TL;DR: In this paper, a novel topology of fractional-order filters, implemented using the internal gate-source capacitance of MOS transistors, is introduced, which is achieved using current-mirrors as active elements, resulting into resistorless realizations due to the employment of the small-signal transconductance parameter of the MOS transistor.
Abstract: Novel topologies of fractional-order filters, implemented using the internal gate-source capacitance of MOS transistors, are introduced in this paper. This has been achieved using current-mirrors as active elements, resulting into resistorless realizations due to the employment of the small-signal transconductance parameter of the MOS transistor. This also offers the capability for electronic tuning of the frequency characteristics of the derived filter structures. The evaluation of the proposed technique has been performed through the design of a generalized fractional-order filter, which is also digitally programmed in such way that the four standard filter functions are offered. The behavior of the filter has been evaluated using the Cadence IC design suite and the Design Kit provided by the Austrian Micro Systems 0.35 μm CMOS process.
01 Jul 2017
TL;DR: In this paper, the authors investigated a passive filter arrangement as an alternative solution to the DC-DC converters and concluded that this passive technique could be an attractive solution especially where high reliability is of concern.
Abstract: The modular structure and the many other advantages of the Modular Multilevel Converter makes it an attractive converter for Battery Energy Storage Systems, allowing the battery units to be distributed throughout the convert, connected in each submodule. However, such an arrangement results in large oscillating components in the battery current, which is harmful to battery performance and lifetime. In most literature this is solved using DC-DC converters as active interfaces between battery and submodule. This paper investigates a passive filter arrangement as an alternative solution to the DC-DC converters. Where the batteries are interfaced with the submodules using a passive filter that suppresses the fundamental component and control technique that injects circulating current to suppress second harmonic component. It is concluded that this passive technique could be an attractive solution especially where high reliability is of concern.
TL;DR: A new second-order current-mode universal filter using only two plus-type differential voltage current conveyors, three resistors and two grounded capacitors is proposed, which can realize high-pass and all-pass filter responses with interconnection of relevant output currents.
Abstract: In this paper, a new second-order current-mode universal filter using only two plus-type differential voltage current conveyors, three resistors and two grounded capacitors is proposed. The proposed circuit with two identical inputs and three outputs can simultaneously provide second-order high output impedance low-pass, band-pass and notch filter responses. Also, it can realize high-pass and all-pass filter responses with interconnection of relevant output currents. It can be easily tuned electronically. It can be operated properly at high frequencies. A number of simulations based on SPICE program and an experimental test are achieved in order to demonstrate the performance of the proposed filter.
01 Jul 2017
TL;DR: In this paper, a piecewise resonant wireless power transfer (PR-WPT) was used to achieve the goal of efficiency, simplicity, and reliability for implantable medical devices in vivo.
Abstract: Wireless power transfer is emerging as the pre-eminent powering technology for implantable medical devices. Efficiency, simplicity, and reliability are the key goals for receivers in vivo. We use piecewise resonant wireless power transfer (PR-WPT) to achieve these goals. A high peak-to-average power ratio (PAPR) waveform is generated by a current-mode class D amplifier operating at 6.78 MHz. A 4∗h-order passive filter is matched to the fundamental and third harmonic voltages of the transmitter, using harmonic elimination for the waveform and closed-form impedance analysis. A full-bridge Schottky rectifier converts the matched voltage into dc. Experiment demonstrates the proof of principle and simulation results show that the piecewise resonant methods can increase the dc output voltage by up to 30%, hence improving the rectifier efficiency. Potential applications for PR-WPT systems are discussed.
TL;DR: In this article, a sensorless active damping technique that is able to restrain the resonant current component through the estimation of the filter capacitor current using the Kalman filter is proposed.
01 Feb 2017
TL;DR: In this paper, a scheme, substation equipped with passive filters, processing the problem of harmonics delivered to power system substation was proposed in order to avoid the harmonics of traction power supply system delivered to superior power systems substation and have a detrimental effect on the quality of public power grid.
Abstract: In order to avoid the harmonics of traction power supply system delivered to superior power system substation and have a detrimental effect on the quality of public power grid, the scheme, substation equipped with passive filters, processing the problem of harmonics delivered to power system substation was proposed in this paper. Based on the measured data of the system substation, the single-tuned filter was designed to eliminate the low-order harmonics and compensate reactive power with considering the effects of capacitor deviation and the system impedance variation. And the second-order high-pass filter was designed to suppress the high-order characteristic harmonics and harmonic resonance with considering the effects on the impedance characteristics under the deviation and fault of the capacitors. The characteristic harmonics, harmonic resonance and the process of harmonics in substation system were simulated in co-simulation model based on power systems computer aided design (PSCAD). The simulation results show that, the designed passive filters have an effective suppression on characteristic harmonics and harmonic resonance.
TL;DR: In this paper, a control strategy for a hybrid filter has been proposed based on minimizing the effective value of the voltage at the point of common coupling to ensure the transfer of the power demanded by the load.
Patent•
13 Apr 2017
TL;DR: In this paper, a converter circuit is provided and includes: a first EMI filter connected to AC lines and includes one or more across-the-line capacitors; a charging circuit that receives power from the first eMI filter and limits an amount of current passing from the EMI filters to a DC bus; and a PFC circuit of a compressor drive that provides PFC between an output of the charging circuit and a generated first DC voltage.
Abstract: A converter circuit is provided and includes: a first EMI filter connected to AC lines and includes one or more across-the-line capacitors; a charging circuit that receives power from the first EMI filter and limits an amount of current passing from the first EMI filter to a DC bus; and a PFC circuit of a compressor drive that provides PFC between an output of the charging circuit and a generated first DC voltage. The PFC circuit includes: a rectification circuit that rectifies the power from the AC lines or a charging circuit output; and a second EMI filter connected downstream from the rectification circuit and including a DC bus rated capacitor. The second EMI filter outputs a filtered DC signal based on a rectification circuit output. The PFC circuit, based on the second EMI filter output, outputs the first DC voltage to the DC bus to power the compressor drive.
01 Sep 2017
TL;DR: In this paper, an optimized 5 kW silicon-carbide (SiC) based three-phase power factor correction (PFC) was designed to achieve the maximum measured efficiency of 99.1% at half of the nominal load and the full load efficiency was achieved.
Abstract: This paper presents designing procedure of a high efficiency 5 kW silicon-carbide (SiC) based three-phase power factor correction (PFC). SiC switches present low capacitive switching loss compared to the alternative Si switches. Therefore, the switching frequency can be increased and hence the size of the line filter (generally reactive components) will be reduced. However, to achieve high efficiency an optimized switching frequency has to be selected. Accordingly the reactive components especially inductors are designed. The core material, winding method, and filter and dc link capacitors are chosen to fulfill the main objective of this paper. Finally, an optimized 5 kW SiC based PFC is designed. Maximum measured efficiency of 99.1% at half of the nominal load is achieved and the full load efficiency is 99%. It is shown that the measured efficiency is substantially flat for a wide range of loads and it is above 99%.
TL;DR: This study presents a model-based controller for a hybrid power filter (HPF) to reduce the current harmonic distortion in a three-phase system for a general operation case considering unbalanced and distorted source voltages and load currents.
Abstract: This study presents a model-based controller for a hybrid power filter (HPF) to reduce the current harmonic distortion in a three-phase system for a general operation case considering unbalanced and distorted source voltages and load currents. The HPF comprises an active power filter (APF) grid connected by means of an LC passive filter. This topology is aimed to reduce the current rating handled by the APF, representing a cost effective solution. The controller design is split into two stages, a first one to control the fundamental component of the system dynamics, and to regulate the DC voltage; and a second stage to compensate the harmonic distortion caused by a non-linear load. For this, the harmonic compensation scheme forces the injection of the required harmonic current to the point of common coupling. The proposed scheme keeps the very familiar proportional-resonant control structure. The compensation of the load reactive current is left to the passive filter. Experimental and simulation results are presented to exhibit the benefits of the proposed control solution.
TL;DR: In this article, the authors presented the current harmonic compensation for the test case of the Quaid-e-Awam University College of Engineering Sciences and Technology (QUCEST) Larkana campus in MATLAB SIMULINK by using three types of power filters i.e. passive, active and hybrid power filters.
Abstract: The increase of power electronic converters at the end-user side is unavoidable and it will cause current harmonic distortion and wide range of disturbance in the power system (PS). This paper presents current harmonic compensation for the test case of the Quaid-e-Awam University College of Engineering Sciences and Technology (QUCEST) Larkana campus in MATLAB SIMULINK by using three types of power filters i.e. passive, active and hybrid power filters. The purpose of this experiment and simulation model is to analyse and find out the best solution for reducing the current harmonic and unbalanced load condition at the incoming transformer to the campus. Moreover, this paper presents the testing and comparison of the active and hybrid power filters by using the combined design technique of harmonic compensate control system based on Unit Vector Template (UVT) and Instantaneous Reactive Power (IRP) theory. The simulation results allow to identify the effectiveness of the control system along with passive filter. Based on the testing and simulation results of three types of power filters, hybrid power filter has the maximum ability to mitigate the current harmonic in the system, and it also reduces the neutral current thus causing less stress in the existing system.
01 Apr 2017
TL;DR: In this paper, the authors proposed an analysis and comparative study of two different schemes of hybrid active power filter (HAPF) configurations with the arrangement of series, passive and shunt filter.
Abstract: Improvement of power quality (PQ) has became an essential aspect in current situation of power system. Conventionally power quality improvement was done through passive filters, shunt filter and series filter but they suffer from problems like resonance, fixed compensation and other PQ problems. Therefore in order to eradicate these issues some hybrid combination of filters including passive and active power filter (APF) are used. This paper proposes an analysis and comparative study of two different schemes of hybrid active power filter (HAPF). HAPF is configured with the arrangement of series, passive and shunt filter. One arrangement is modeled with shunt passive filter linked in series with shunt active filter and the other is designed with series active filter and shunt passive filter. For both the schemes of hybrid filter, different control strategy and power circuit design are considered. Finally for individual configuration the control and compensation design is proved by simulation.
01 Nov 2017
TL;DR: A proposed model of passive Alter & combination of shunt active & passive filter to reducing harmonic limits in single-phase system as tracked by IEEE std.
Abstract: We know that the rise of harmonics is a major problem now days in non-linear loads. The universal use of non-linear loads like in power electronics equipment which amplified the harmonic-related difficulties in service and trade power systems this make an essential requirement of filter. The nonlinear loads be compensated & sometime we can identified but sometimes they include their own non characteristic harmonic portion & not ideal as it is actual in input & voltage sag occur so many times in a day. As increasing the harmonic magnitude component contribution of key problem also rises in industrial sector, so this is a very complex in power system, to overcome we using different methods to reduce this major problem. This paper is presents a proposed model of passive Alter & combination of shunt active & passive filter to reducing harmonic limits in single-phase system as tracked by IEEE std. 519-1992.
01 Jul 2017
TL;DR: In this article, a Memristor-Memcapacitor-LPF was proposed, and the amplitude-frequency response, phasefrequency response and phase-frequency responses were analyzed.
Abstract: The paper highlights a way to introduce memristive components into the filter circuit. In light of memristor and memcapacitor, a novel low pass filter circuit (LPF) is presented. First, inspired by the typical RC-LPF and the Memristor-C-LPF, a novel Memristor-Memcapacitor-LPF is designed. Then transfer function of the LPF is obtained, and the amplitude-frequency response, phase-frequency response are presented. Finally, Simulation results demonstrates our analysis, and the memristive elements can be extended to the other filter circuits.
01 Sep 2017
TL;DR: In this article, a hierarchical cascading FEM software called "Layers" is proposed for simulating any 2D SAW device with hundreds of electrodes with a speed of 1sec-4sec.
Abstract: SAW filter technology includes different substrates, multilayered electrodes from Al, Cu, Pt, …, dielectric sublayers and over-layers, etc. Temperature compensated SAW filters have been developed that have performance competitive with FBARs. Traditional design tools, such those as based on COM models, demand experimental characterization of wave propagation parameters. FEM/BEM models cannot be easily adopted to new substrates and calculations are slow. The advantage of FEM methods is their remarkable generality. FEM can handle arbitrary materials and crystal cuts, different electrode shapes, and structures including multiple metal and dielectric layers. The main challenge in applying FEM to SAW devices has been unacceptably long computation times. Recently, we proposed “hierarchical cascading” FEM software called “Layers” [1], suitable for simulating any 2D SAW device with hundreds of electrodes with a speed of 1sec.–4 sec. per frequency point on a 32 processor PC. Note that exact acoustic and electric field distributions can be calculated for all points of the device. A 5-IDT CRF/DMS TC SAW filter has been simulated using “Layers” [1]. In addition to the 10-port electrical network parameters for the filter, a visualization of acoustic field and power flow is presented (Fig. 1). Simulation reveals the resonances in the structure, radiation of energy at the interfaces between IDTs, and the origin of notches in passband including parasitic acoustic modes.
TL;DR: This paper describes a new single-input multiple-output (SIMO) mixed-mode universal biquad Gm–C filter that can realize all kinds of filter responses including high-pass, band- pass, low-pass; band-stop and all-pass filters, simultaneously.
Abstract: This paper describes a new single-input multiple-output (SIMO) mixed-mode universal biquad Gm–C filter. It can realize all kinds of filter responses including high-pass, band-pass, low-pass, band-stop and all-pass filters, simultaneously. Moreover, in this structure, all of these filters in all states of voltage mode, current mode, transresistance mode and transconductance mode are achieved by the same topology without any convertor. The proposed filter employs three operational transconductance amplifiers (OTAs) with four inputs and one output, three fully differential OTAs and two grounded capacitors. In other words, this filter is composed of six Gm blocks and two grounded capacitors. The grounded capacitors are suitable for integrated circuit implementation. In order to reduce the power consumption, the OTAs are biased in subthreshold region. In addition, sensitivity analysis is included to show the low active and passive sensitivity performances of the filter. This filter is designed and simulated in HSPICE with 0.18μm model CMOS technology parameters. The simulation results show that the filter consumes only 75μW and operates at 1.5MHz with ±0.5V supply voltages and capacitors C1=C2=2pF.