Showing papers on "Inductor published in 2022"
TL;DR: In this paper , an inductor-capacitor (LC) resonant tank-based wireless pressure sensor, screen-printed on an electrospun Poly-L-lactide (PLLA) nanofibers-based flexible, biocompatible, and piezoelectric substrate is presented.
Abstract: Easy to use multifunctional wearable devices, with no wires hanging around, are needed for real time health monitoring at user's comfort. Herein, an inductor‐capacitor (LC) resonant tank‐based wireless pressure sensor, screen‐printed on an electrospun Poly‐L‐lactide (PLLA) nanofibers‐based flexible, biocompatible, and piezoelectric substrate is presented. The printed resonant tank (resonant frequency of ≈13.56 MHz) consists of a planar inductor connected in parallel with an interdigitated capacitor. The capacitance, of the interdigitated capacitor present on the piezoelectric substrate varies in response to applied pressure. As a result, the resonant frequency changes and the LC tank works as a wireless pressure sensor. The sensor exhibited high sensitivity 0.035 kP−1 and 1200 Hz kPa−1 in wireless operation with excellent durability (over 1800 cycles). The sensitivity is the highest (1.75‐fold higher) among printed wireless pressure sensors reported so far. Finally, the presented LC tank‐based pressure sensor is integrated on a compression bandage to demonstrate its potential use in the online monitoring of sub‐bandage pressure. The application of optimum pressure by the bandage, together with the electroceutical arrangement facilitated by the piezoelectric PLLA substrate, can accelerate the cell regeneration and hence wound healing.
46 citations
TL;DR: This letter presents a new low-voltage direct-current fault current bypass-based solid-state circuit breaker (SSCB) using silicon-carbide mosfets that provides the possibility to select the clamping voltage of metal–oxide varistors close to the nominal voltage of the dc system.
Abstract: This letter presents a new low-voltage direct-current fault current bypass-based solid-state circuit breaker (SSCB) using silicon-carbide mosfet s. The proposed SSCB provides the possibility to select the clamping voltage of metal–oxide varistors (MOVs) close to the nominal voltage of the dc system. This reduces voltage overshoots across the main switch and snubber components and extends the maximum allowable dc bus voltage on the SSCB. The MOVs are removed from the power line, and their leakage currents are completely eliminated. The clamping voltage of the MOV and its surge energy rating is considered to optimize the MOV. The dv/dt across the main switchis controlled by an auxiliary capacitor, where a design procedure is presented to optimize its value. Also, the stored inductive energy of the line inductor in dc systems is bypassed using an auxiliary branch and prevented from flowing through the faulty section to enhance the safety. LTspice simulations are presented to show the significance of the proposed SSCB. The experiments of 375 V/170 A/2.4 μs and 600 V/163 A/2.4 μs verify the effectiveness of the proposed design in practice.
40 citations
TL;DR: In this article , an efficient two-stage charger topology with an improved PFC rectifier as front-end and a high-frequency zero voltage switching (ZVS) DC/DC converter is introduced.
Abstract: A plug-in hybrid electric vehicles (PHEV) charger adapter consists of an AC/DC power factor correction (PFC) circuit accompanied by a full-bridge isolated DC/DC converter. This paper introduces an efficient two-stage charger topology with an improved PFC rectifier as front-end and a high-frequency zero voltage switching (ZVS). Current switching (ZCS) DC/DC converter is the second part. The front-end converter is chosen as bridgeless interleaved (BLIL) boost converter, as it provides the advantages like lessened input current ripple, capacitor voltage ripple, and electromagnetic interference. Resettable integrator (RI) control technique is employed for PFC and DC voltage regulation. The controller achieves nonlinear switching converter control and makes it more resilient with the faster transient response and input noise rejection. The second stage incorporates a resonant circuit, which helps in achieving ZVS/ZCS for inverter switches and rectifier diodes. PI controller with phase shift modulator is used for second-stage converter. It improves the overall efficacy of the charger by lowering the switching losses, lowering the voltage stress on the power semiconductor devices, and reversing recovery losses of the diodes. The simulations and experimental results infer that the overall charging efficiency increases to 96.5%, which is 3% higher than the conventional two-stage approach using the interleaved converter.
30 citations
TL;DR: In this paper , a misalignment-tolerant dual-transmitter EV wireless charging system with a reconfigurable topology is proposed, where the two transmitting coils are connected in series to feed the load.
Abstract: Wirelesscharging for electric vehicles (EVs) enjoys many benefits, such as convenience, safety, and automation. One of the major issues concerning EV wireless charging is misalignment tolerance along the door-to-door direction of the EV. This letter proposes a misalignment-tolerant dual-transmitter EV wireless charging system with a reconfigurable topology. At central positions, the system can be reconfigured to the S-S (series-series) topology where the two transmitting coils are connected in series to feed the load. At boundary positions, the two transmitting coils form the LCCC-S (inductor-capacitor-capacitor-capacitor-series) topology to enhance power transfer capability and tolerate weak couplings. In this way, not only the output power can be smoothed with door-to-door misalignment, but also wireless charging is guaranteed at weak couplings. Experimental results reveal that within the cover area of the transmitting coils, high-efficiency stable output can be achieved.
30 citations
TL;DR: A volume reduction method of CM inductors with chaotic PWM (CPWM) is proposed, and the volume of CM EMI filters are reduced by 63.5% and 48.3%, respectively, by using the proposed compact EMI filter.
Abstract: Passive electromagnetic interference filters (PEFs) are the most common way to solve electromagnetic interference (EMI) problems in power converters. However, PEFs bring additional volume, weight, and cost for power converters, especially common-mode (CM) inductors in PEFs, and it is a tricky issue for the high-power-density converters that must meet the electromagnetic compatibility specification. In order to design compact PEFs for power converters with pulsewidth modulation (PWM), a volume reduction method of CM inductors with chaotic PWM (CPWM) is proposed in this article. First, the mechanism that CPWM reduces the CM inductance by increasing the corner frequency is analyzed. Second, the relationship between the reduction of EMI spectrum magnitude by CPWM and the decrease of the CM inductance is quantitatively calculated. Third, utilization rate of the magnetic core η is defined to reasonably compare the size of the different inductors under traditional PWM and CPWM. Finally, the proposed design method of CM EMI filters is applied into a dc–dc converter and a dc–ac inverter, respectively, to verify its effectiveness and feasibility. In a dc–dc converter with the switching frequency 100 kHz, 275 W, the volume of the CM inductor and the volume of CM EMI filters are reduced by 63.5% and 48.3%, respectively, by using the proposed compact EMI filter.
27 citations
TL;DR: In this article, a double T-type resonant network was proposed for wireless power transfer for mobile devices, which achieved self-protection under severe load change and entered standby mode automatically after the pick-up was moved out.
Abstract: In the applications of wireless power transfer for mobile devices, the pick-up of the wireless power transfer system often needs to be moved in and moved out. A sudden change in the system structure will cause high transient voltages or currents, which could damage the power electronic device of the capacitive power transfer (CPT). In addition, the standby power of the system will be too high to work after removing the pick-up. A CPT system with double T-type resonant networks has been proposed to address these problems. The steady-state models of the system without the pick-up and normal state conditions of it are established. The relationships between the resonant network parameters are analyzed, and a systematic circuit parameter design method is provided. The proposed CPT topology and the parameter design method have been verified by simulation and experiment. The system not only achieved self-protection under severe load change but also entered standby mode automatically after the pick-up was moved out. Besides, the system is restored to the normal state condition when the pick-up is moved in without additional detection and control circuitry.
27 citations
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TL;DR: The chemical inductor as mentioned in this paper is a two-dimensional system that couples a fast conduction mode and a slowing down element, and it is defined in dynamical terms rather than by a specific physicochemical mechanism.
Abstract: A multitude of chemical, biological, and material systems present an inductive behavior that is not electromagnetic in origin. Here, it is termed a chemical inductor. We show that the structure of the chemical inductor consists of a two-dimensional system that couples a fast conduction mode and a slowing down element. Therefore, it is generally defined in dynamical terms rather than by a specific physicochemical mechanism. The chemical inductor produces many familiar features in electrochemical reactions, including catalytic, electrodeposition, and corrosion reactions in batteries and fuel cells, and in solid-state semiconductor devices such as solar cells, organic light-emitting diodes, and memristors. It generates the widespread phenomenon of negative capacitance, it causes negative spikes in voltage transient measurements, and it creates inverted hysteresis effects in current–voltage curves and cyclic voltammetry. Furthermore, it determines stability, bifurcations, and chaotic properties associated to self-sustained oscillations in biological neurons and electrochemical systems. As these properties emerge in different types of measurement techniques such as impedance spectroscopy and time-transient decays, the chemical inductor becomes a useful framework for the interpretation of the electrical, optoelectronic, and electrochemical responses in a wide variety of systems. In the paper, we describe the general dynamical structure of the chemical inductor and we comment on a broad range of examples from different research areas.
27 citations
TL;DR: A high gain three-port converter with soft switching is proposed in this paper, which can realize zero voltage switching for all switches and zero current switching forall diodes in various operating modes.
Abstract: Three-port converters with high voltage gain are desirable solutions for integrating renewable energy and energy storage devices into high voltage dc bus. A high gain three-port converter with soft switching is proposed in this paper, which can realize zero voltage switching for all switches and zero current switching for all diodes in various operating modes. Single coupled inductor is used to achieve high voltage gain and to reduce the voltage stress of switches so that switches with low on -resistance can be selected to reduce the conduction loss. In addition, the advantages of fewer components, higher voltage gain, and very low switch voltage stresses make the proposed converter more suitable for application in renewable energy systems than similar solutions. Various operating modes, performance analysis, design considerations, efficiency analysis, and control method of the proposed converter are discussed. A laboratory prototype with 30 V renewable energy source, 48 V energy storage device and 400 V output is designed to verify the performance of the proposed three-port converter.
27 citations
TL;DR: In this article , a hybrid-switched-capacitor converter with a merged-two-stage hybrid-SWC was proposed for ultra-high-current microprocessors.
Abstract: This article presents a 48–1 V merged-two-stage hybrid-switched-capacitor converter with a linear extendable group operated point-of-load (LEGO-PoL) architecture for ultrahigh-current microprocessors, featuring 3-D stacked packaging and coupled inductors for miniaturized size, fast speed, and vertical power delivery. The architecture is highly modular and scalable. The switched-capacitor circuits are connected in series on the input side to split the high input voltage into multiple stacked voltage domains. The multiphase buck circuits are connected in parallel to distribute the high output current into multiple parallel current paths. It leverages the advantages of switched-capacitor circuits and multiphase buck circuits to achieve soft charging, current sharing, and voltage balancing. The inductors of the multiphase buck converters are used as current sources to soft-charge and soft-switch the switched-capacitor circuits, and the switched-capacitor circuits are utilized to ensure current sharing among the multiphase buck circuits. A 780-A vertical stacked CPU voltage regulator with a peak efficiency of 91.1% and a full load efficiency of 79.2% at an output voltage of 1 V with liquid cooling is built and tested. The switched capacitor circuits operate at 286 kHz and the buck circuits operate at 1 MHz. It regulates output voltage between 0.8 and 1.5 V through the entire 780-A current range. This is the first demonstration of a 48–1 V CPU voltage regulator to achieve over 1-A/mm $^\text{2}$ $^3$
25 citations
TL;DR: In this converter, the number of voltage multiplier cells, and the coupled inductors turn ratios provide three degrees of design freedom to set the desired voltage stresses of the semiconductors within the desired range and to provide a high voltage gain at optimum duty cycles.
Abstract: In this article, a novel ultrahigh voltage gain dc–dc boost converter with expandable diode-capacitor voltage multiplier (VM) cells is presented. The diode-capacitor VM cells and coupled inductors are employed in the presented topology to provide a higher voltage gain. Also, the main and the auxiliary power switches of the presented converter operate with zero voltage switching. The coupled inductors' leakage inductances control the rates of the current drop in the voltage multiplier diodes, which decreases their reverse recovery losses markedly. Moreover, the voltage stresses on all capacitors and semiconductors are reduced significantly. In this converter, the number of voltage multiplier cells, and the coupled inductors turn ratios provide three degrees of design freedom. These degrees of freedom are used to set the desired voltage stresses of the semiconductors within the desired range and to provide a high voltage gain at optimum duty cycles. The design and theoretical analysis of the presented converter are discussed. Finally, the performance of the presented converter is validated using a 500 W, 40 V/380 V laboratory prototype converter, and the experimental results confirm the theoretical calculation.
25 citations
TL;DR: In this article, an interleaved high-voltage gain dc-dc converter is proposed for use with photovoltaic (PV) systems, which integrates two three-winding coupled inductors (CIs) with switched capacitor cells.
Abstract: In this article, an interleaved high-voltage gain dc–dc converter is proposed for use with photovoltaic (PV) systems. By integrating two three-winding coupled inductors (CIs) with switched capacitor cells, the voltage gain is further extended. Through passive diode-capacitor clamp circuits, the energy stored in the leakage inductances is absorbed; additionally, the voltage stress of the power switches is clamped to a value far lower than the output voltage, which enables designers to select switches with low-voltage ratings. Due to the interleaved structure of the proposed converter, the input current has a small ripple, which leads to the increased lifespan of the PV panels. In addition, the current stress on the components is reduced. Thanks to the leakage inductances of the CIs, the zero-current switching condition is intrinsically provided for the diodes; accordingly, the adverse impact of the diodes’ reverse-recovery is alleviated. The operating principles, steady-state analyses, and design considerations of the proposed converter are presented in this article. A comparison with other similar converters is carried out to verify the merits of the proposed converter. Finally, the theoretical analyses are confirmed through the experimental results of a 400-W prototype with an output voltage of 400 V.
TL;DR: Large-signal modeling of the two-module system and the accuracy of this model in two cases of radiation change and panel temperature change is investigated, and the robustness of the system is investigated.
Abstract: Voltage imbalance poses a challenge to photovoltaic systems. A modular structure based on a three-level boost converter is proposed to address this problem. The three-level boost converter offers advantages, such as a low current ripple and voltage stress, over a classic boost converter. These advantages offset the use of additional elements in the proposed converter circuit. Two capacitors are used to enable the innovative connection between multiple sources and the three-level boost converter. The second capacitor of the first module is shared with the first capacitor of the second module. This structure is used in conjunction with a controller to balance the voltages in the system. The operating modes of the two-module system in a nominal case are introduced. The controller is based on an indirect sliding model, wherein the input current of each energy source and the output voltage balance are considered. The performance of the current and voltage controllers are studied in two scenarios. The first case involves increasing the reference current and the presence of four sliding surfaces related to the current control and voltage balance, whereas the second case involves the presence and absence of two sliding surfaces related to the voltage balance. The dynamic response of this controller is also compared with the Proportional Integral(PI) controller. Large-signal modeling of the two-module system and the accuracy of this model in two cases of radiation change and panel temperature change is investigated. The robustness of the system is investigated using this large-signal model in two cases that involve changing the inductors and capacitors of the system. A topology consisting of two conventional boost converters is chosen to compare energy stored and efficiency with the proposed topology. The capacitance of the system is calculatedfor two topologies. The energy stored in the two systems is compared. The two-module system is simulated using Simulink MATLAB software. The simulation and experimental results validate the proposed system.
TL;DR: In this paper , a detailed classification of resonant converters used in chargers of electric vehicles (EVs) is presented, which provides a guideline to designers to choose a converter topology used in the first stage and the second stage of EV charger required based on wattage, unidirectional and bidirectional power flow.
TL;DR: In this paper, an integrated parallel buck-boost and boost converter (IPB3C) is proposed as an electrolytic-capacitor-less light-emitting diode (LED) driver.
Abstract: In this article, an integrated parallel buck–boost and boost converter (IPB3C) is proposed as an electrolytic-capacitor-less light-emitting diode (LED) driver. The IPB3C provides a high power factor (PF) and low total harmonic distortion (THD). The driver is composed of two converters that are connected in parallel, using just one controlled switch. The buck–boost duty is to deliver constant power to the LED, while ensuring a good PF. The boost converter is employed to cancel the low-frequency ripple at the LED. In return, this decreases the flicker effect and only a relatively small capacitance is needed to fulfill the standard requirements. The buck–boost converter handles the full power of the LED, while the boost converter handles only a portion of the LED power. Thus, better efficiency is ensured by this parallel configuration compared to conventional cascaded integrated converters. Moreover, the voltage across the switch is low, as it is the higher, whether buck–boost or boost converter, but not the addition of both. In this article, the IPB3C is analyzed, and its design methodology is presented. A universal input voltage range prototype of the proposed converter supplying an LED lamp of 108-V/ 0.35-A is presented. The prototype shows high PF, nearly equal to one, very small THD, nearly zero, output voltage ripple of 4.5%, output current ripple of 19%, and high efficiency, equal to 92.4%. Moreover, the converter requires the use of a bulk capacitance of only 68 μF, while the required output capacitance is just 1 μF.
TL;DR: In this article , the authors provide a comprehensive review of the power factor correction (PFC) converters in short-and long-distance electric vehicles (e.g., e-bikes, e-trikes, erickshaw, and golf carts).
Abstract: Electrification of the transportation sector has originated a worldwide demand towards green-based refueling infrastructure modernization. Global researches and efforts have been pondered to promote optimal Electric Vehicle (EV) charging stations. The EV power electronic systems can be classified into three main divisions: power charging station configuration (e.g., Level 1 (i.e., slow-speed charger), Level 2 (i.e., fast-speed charger), and Level 3 (i.e., ultra-fast speed charger)), the electric drive system, and the auxiliary EV loads. This paper emphasizes the recent development in Power Factor Correction (PFC) converters in the on-board charger system for short-distance EVs (e.g., e-bikes, e-trikes, e-rickshaw, and golf carts) and long-distance EVs (passenger e-cars, e-trucks, and e-buses). The EV battery voltage mainly ranges between 36 V and 900 V based on the EV application. The on-board battery charger consists of either a single-stage converter (a PFC converter that meets the demands of both the supply-side and the battery-side) or a two-stage converter (a PFC converter that meets the supply-side requirements and a DC-DC converter that meets the battery-side requirements). This paper focuses on the single-phase unidirectional non-isolated PFC converters for on-board battery chargers (i.e., Level 1 and Level 2 charging infrastructure). A comprehensive classification is provided for the PFC converters with two main categories: (1) the fundamental PFC topologies (i.e., Buck, Boost, Buck-Boost, SEPIC, Ćuk, and Zeta converters) and (2) the modified PFC topologies (i.e., improved power quality PFC converters derived from the fundamental topologies). This paper provides a review of up-to-date publications for PFC converters in short-/long-distance EV applications.
TL;DR: A novel dc–dc light-emitting diode driver employing an interleaved converter is proposed and analyzed, and the circuit efficiency as high as 95.0% is measured and satisfactory performance has verified the feasibility of the proposed converter.
Abstract: In this article, a novel dc–dc light-emitting diode driver employing an interleaved converter is proposed and analyzed. The circuit topology mainly consists of two parallel buck–boost converters. A coupled inductor, which is composed of a magnetic core and two windings, is used to replace the energy storage inductors of the two buck–boost converters. This not only does not add any components, but also saves a magnetic core. The buck–boost converters are designed to operate near boundary conduction mode. Due to the characteristics of magnetic flux balance, the magnetic-excited current can be converted between the windings of the coupled inductor. By using the magnetic-excited current to release the charge stored in the parasitic capacitors of the active switches, these switches can fulfill zero-voltage switching on (ZVS) without the use of any auxiliary switches, active clamping circuits, or snubber circuits. Moreover, the freewheel diodes of both buck–boost converters can achieve zero-current switching off (ZCS). The steady-state analyses for different operation modes are provided, and the mathematical equations for designing circuit components are conducted. Finally, a 200-W prototype circuit was built and tested to verify the analytical predictions. According to the experimental results, all the semiconductor devices are operated at either ZVS or ZCS, and the circuit efficiency as high as 95.0% is measured. Satisfactory performance has verified the feasibility of the proposed converter.
TL;DR: In this article , a bridgeless Cuk-derived power factor corrected (PFC) converter with reduced component count for on-board EV charging application is proposed, where the output inductor of the converter is operated in discontinuous current mode to attain PFC naturally at ac mains.
Abstract: This article proposes a novel single-phase bridgeless Cuk-derived power factor corrected (PFC) converter with reduced component count for on-board EV charging application. The unique feature of this proposal is to design and operate the output inductor of the converter in discontinuous current mode for the complete power range to attain PFC naturally at ac mains, thereby not requiring the input voltage and input current sensing, which reduces the converter cost, and improves the power density as well as converter robustness to high-frequency noise. The converter control is very simple in operation and easy in implementation with only a single sensor-based voltage control loop. The semiconductor components voltage stress of the proposed power converter is lower when compared to the traditional Cuk converter. The simulation results from PSIM 11 and experimental results are given by testing a proof-of-concept hardware laboratory prototype to demonstrate the high performance of PFC operation of the proposed converter.
TL;DR: In this paper, a multicoupling LCC-compensated method for EVDWC system based on an integrated magnetic coupler to suppress the power fluctuation is proposed, where the main advantage of the proposed method is to realize compensation inductance using coupling coils, thereby adding two cross-couplings.
Abstract: In the electric vehicle dynamic wireless charging (EVDWC) system, when the electric vehicle (EV) drives from one track to the next, it will produce output power fluctuation. This article proposes a multicoupling LCC-compensated method for EVDWC system based on an integrated magnetic coupler to suppress the power fluctuation. The magnetic coupler includes three couplings. The first coupling is between the main coils. The second coupling is between the adjacent compensation inductor coils integrated into main coils. The third coupling is between the primary compensation inductor coils and the secondary compensation inductor coil. The main coils are unipolar and the compensation inductor coils are in a double D structure. The parameter matching rules and optimized design process considering the additional cross-couplings are given. The main advantage of the proposed method is to realize compensation inductance using coupling coils, thereby adding two cross-couplings, and to suppress output power fluctuation based on system normal operation without adding new components. A prototype is designed and implemented to validate the proposed magnetic coupler and parameter design rules. Experimental results show that the output power fluctuation is within ±4% during dynamic charging at a power level of 12 kW, and the maximum efficiency reaches 92.3%.
TL;DR: In this article , an enhanced gate-driver, auxiliary power supply network, PCB planar dc-bus, and high-density inductor are presented, enabling the SiC-based designs in modular medium-voltage (MV) power conversion.
Abstract: Simultaneously imposed challenges of high-voltage insulation, high $\mathrm{d}v/\mathrm{d}t$ , high-switching frequency, fast protection, and thermal management associated with the adoption of 10 kV SiC MOSFET, often pose nearly insurmountable barriers to potential users, undoubtedly hindering their penetration in medium-voltage (MV) power conversion. Key novel technologies such as enhanced gate-driver, auxiliary power supply network, PCB planar dc-bus, and high-density inductor are presented, enabling the SiC-based designs in modular MV converters, overcoming aforementioned challenges. However, purely substituting SiC design instead of Si-based ones in modular MV converters, would expectedly yield only limited gains. Therefore, to further elevate SiC-based designs, novel high-bandwidth control strategies such as switching-cycle control (SCC) and integrated capacitor-blocked transistor (ICBT), as well as high-performance/high-bandwidth communication network are developed. All these technologies combined, overcome barriers posed by state-of-the-art Si designs and unlock system level benefits such as very high power density, high-efficiency, fast dynamic response, unrestricted line frequency operation, and improved power quality, all demonstrated throughout this paper.
TL;DR: In this article, a virtual controllable voltage source (VCVS) is constructed by an auxiliary winding of the other phase transformer inserted into the resonant tank, which can be regulated to achieve current sharing by modulating the phase-shift angle between the two phases.
Abstract: In this letter, a novel current sharing scheme for two-phase interleaved LLC converter based on virtual controllable voltage sources (VCVSs) is proposed. In each phase, the VCVS is constructed by an auxiliary winding of the other phase transformer inserted into the resonant tank. The equivalent input voltage of resonant tank, which is the composition of the equivalent ac input voltage and VCVS, can be regulated to achieve current sharing by modulating the phase-shift angle between the two phases. Meanwhile, good output current ripple cancellation effect can be naturally achieved with appropriate parameters of VCVSs. Detailed operation principle and design considerations of the proposed current sharing method are presented. Finally, a 12 V/40 A two-phase interleaved LLC prototype has been built up to verify the theoretical analysis.
TL;DR: Theoretical analyses show that the proposed scheme can mitigate the dc-link current ripple over the full index range for a CSC and its carrier-based modulation, which can automatically select the desired vectors and last predetermined dwell times, is presented.
Abstract: This article presents a direct carrier-based modulation scheme to mitigate the dc-link current ripple for a current source converter (CSC) Excessive dc-link current ripple increases system losses, causes current distortion, and leads to more electromagnetic interference, so, it should be mitigated Compared with increasing dc-link inductor or switching frequency, it is more attractive to mitigate dc-link current ripple with modulation schemes However, existing modulation schemes suffer from either high dc-link current ripple or shrink of modulation index range To address this issue, this article analyzes the mechanism of mitigating the dc-link current ripple and proposes a new modulation scheme for a CSC By employing two kinds of non-nearest three vectors to synthesize the reference current, the proposed scheme successfully extends the index range from [ $\sqrt 3 /3$ , 1] to [0, 1] For easier implementation, its carrier-based modulation, which can automatically select the desired vectors and last predetermined dwell times, is also presented Theoretical analyses show that the proposed scheme can mitigate the dc-link current ripple over the full index range for a CSC The effectiveness of the proposed modulation scheme is verified experimentally with a CSC operating as a rectifier
TL;DR: In this paper , a hybrid transformerless high voltage gain dc-dc converter was created by merging a two-inductor boost converter with voltage multiplier and switched capacitor cells, which reached a maximum efficiency of 98.24%.
Abstract: In this article, a new hybrid transformerless high voltage gain dc–dc converter was created by merging a two-inductor boost converter with voltage multiplier and switched capacitor cells. The main advantages of the proposed converter are high voltage gain, simplicity of operation, high efficiency, lower voltage, and lower current stresses on the components. A 200 W, 37.4 V/400 V, 100 kHz prototype was implemented in the laboratory to evaluate the proposed converter, which reached a maximum efficiency of 98.24 $\%$
TL;DR: A fault-tolerant dual active bridge (DAB) converter is proposed to maintain the power transferring ability under multiple unexpected open-circuit faults (OCFs) conditions, which can significantly enhance the reliability of the dc power transmission system.
Abstract: The dc power transmission system has been obviously attracting more research interests in recent years. In order to satisfy the high-reliability requirement of the dc power transmission system, the power converter should be able to keep uninterrupted operation after multiple unexpected faults. However, high fault-tolerant capability usually leads to the bulky redundant circuit, which increases the cost, volume, and complexity of the power converter. Thus, a fault-tolerant dual active bridge (DAB) converter is proposed to maintain the power transferring ability under multiple unexpected open-circuit faults (OCFs) conditions, which can significantly enhance the reliability of the dc power transmission system. By reconfiguring the central-tapped transformer and two symmetrical auxiliary inductors, the half-bridge conduction branch is built to maintain uninterrupted operation when a single or dual OCF has occurred. The proposed fault-tolerant strategy only requires four extra voltage sensors to detect and locate OCFs for the reconfiguration process. Thus, it significantly improves the system reliability with a low additional cost. Besides, the inductor current, transmission power, and the small-signal models of the proposed fault-tolerant converter have been presented. It proves the proposed fault-tolerant topology can smoothly switch between normal and postfault operation due to the constituency of the inductor current. Finally, the 250-W prototype is designed to verify the advantage of the proposed fault-tolerant DAB converter.
TL;DR: In this article , a deep insight into the passivity-based design of LCL-filtered inverter with grid current control and capacitor current active damping is presented.
Abstract: This article takes a deep insight into the passivity-based design of LCL-filtered inverter with grid current control and capacitor current active damping. It reveals that although an optimal damping gain can theoretically ensure the passivity, it is susceptible to both the lagging phase of the current regulator and the fluctuations of filter parameters. After thoroughly assessing the impacts of these two factors, proper phase compensations are proposed to enhance the passivity. It is found that a phase-lead or phase-lag compensator is needed, depending on the relation of the one-sixth of the sampling frequency to the resonance frequency of inverter-side inductor and filter capacitor. The guidelines on the compensation selection and parameter design are provided. Simulation and experimental results are conducted to verify the theoretical analysis.
TL;DR: In this paper, the authors proposed a new nonisolated full soft-switching step-up dc/dc converter based on single-ended primary inductor converter (SEPIC) structure.
Abstract: This article introduces a new nonisolated full soft-switching step-up dc/dc converter based on single-ended primary inductor converter (SEPIC) structure. The proposed topology utilizes a three-winding coupled-inductor (TWCI) to increase the voltage gain, but unlike other coupled-inductor-based converters, its voltage gain is increased by reducing its magnetic turns ratio. Moreover, the secondary and tertiary turns ratios of the TWCI can be used as an additional design freedom to extend the voltage gain, which indicates more converter flexibility. Due to the continuous input current, the proposed converter can be used for many types of renewable energy sources. Also, the leakage energy from the TWCI has further been recycled and transferred to the output with the help of a regenerative passive clamp circuit. Due to the soft-switching performance, the proposed converter has no switching losses at the turn- on instant for the power switch and reverse recycling losses of the diodes. Furthermore, the use of a small number of components along with the soft-switching performance offer high efficiency. Steady-state analysis and design considerations are discussed thoroughly. Finally, a 200-W prototype with 200 V output voltage is provided to verify the theoretical analysis.
TL;DR: In this article , the authors investigated the sensitivity of LCC-LCC-compensated topology to the variation of the parallel compensated capacitors and found that the variation has the greatest impact on the output power.
Abstract: The characteristics of inductive power-transfer (IPT) systems are sensitive to the variation of the coupling coefficient caused by misalignment conditions or different gaps. This results in a reduction in transferred power and efficiency. The output characteristics considering frequency modulation applied in series–series (SS), inductor–capacitor–capacitor (LCC)-S and LCC–LCC compensated IPT systems have been explored, revealing that high-order compensation topologies hold limited power regulation ability if coupling varies significantly. The parameter sensitivity of LCC–LCC-compensated topology is investigated through the singular values (SVs) analysis. It is found that the variation of the parallel-compensated capacitors has the greatest impact on the output power. Aiming at alleviating the power drop caused by the coupling variation, a parameter offline tuning method realized by switching the parallel-compensated capacitance for a detuned LCC–LCC resonant converter is proposed for electric vehicle (EV) wireless charging. Analytical expressions have been derived in aiding the design of modified value of capacitance ensuring primary zero voltage switching (ZVS) operation. Thus, the detuned parameter combinations, which deliver rated power even with the worst coupling, are obtained. Finally, a 6.6-kw prototype has been built to verify the validity of the proposed topology, which can deliver 6.1 kW with an efficiency of 94% even when the coupling drops from 0.3 to 0.15.
TL;DR: In this paper , an optimal structure for a high step-up nonisolated dc-dc converter is proposed, and the performance of the proposed converter, in terms of voltage stress, voltage gain, and efficiency, has been analyzed, and a comprehensive comparison between the presented topology and other similar topologies presented.
Abstract: In this article, an optimal structure for a high step-up nonisolated dc–dc converter is proposed. In this topology, the required high voltage gain can be obtained with a low number of elements. Furthermore, by implementing an auxiliary circuit, zero-voltage switching condition for the switches is provided, input current ripple has been reduced to almost zero, and all of the power diodes turn off and on under zero-current conditions. In the proposed structure, to regulate voltage gain, the extendable number of diode–capacitor voltage multiplier (DCVM) stages are combined with a coupled inductor. The voltage stresses across the semiconductors can be regulated by the number of the DCVM stages and the turns ratio of the coupled inductor. Thus, it provides two degrees of freedom for the designer to use low-rated semiconductors, which increases the converter efficiency. In this article, the performance of the proposed converter, in terms of voltage stress, voltage gain, and efficiency, has been analyzed, and a comprehensive comparison between the presented topology and other similar topologies presented. Finally, to verify the performance of the proposed topology, a 500 W (40 V/400 V) laboratory prototype has been developed and tested. The experimental results confirm its superiority and suitability.
TL;DR: In this article , an ultra-high step-up dc-dc converter with a combination of two stages boost converter, a coupled inductor, and a multiplier cell is proposed, which can achieve high voltage gain, low voltage stress on its power switches, and requiring a smaller inductor on low voltage side of the converter.
Abstract: In this article, an ultrahigh step-up dc–dc converter is proposed with a combination of two stages boost converter, a coupled inductor, and a multiplier cell. The secondary side of the coupled inductor is unified with the multiplier cell. In addition, leakage energy of the coupled inductor is recycled and transferred to output perfectly which causes high-efficiency performance. The main advantages of the converter include its high voltage gain, low voltage stress on its power switches, and requiring a smaller inductor on low voltage side of the converter. Power losses of the inductors are low due to the current sharing between the input inductor and the coupled inductor. Continuity of input current and existence of a common ground between the load and source make the converter suitable for different applications. The converter is compared with the other converters based on an analysis of its operation modes. Validity of the analysis and the converter performance are experimented using a 150-W prototype that converts 20 V from the input side to 400 V in output.
27 May 2022
TL;DR: In this paper , a lift converter with three-winding coupled inductors is used to increase the amount of voltage gain, there is a method called soft switching is being used for the sake of decrease losses in the diode and to decrease the voltage stress at switch and also helps in creating the absence of reverse recovery diodes.
Abstract: In Photo Voltaic system, this idea of converter can be used to increase efficiency. For increase of voltage gain advantage, advised architecture accommodates a lift converter with proper coupled inductors. It has benefits like continuous input current, high amount of efficiency, three-winding coupled inductors generally used to increase the amount of voltage gain, there is a method called soft switching is being used for the sake of decrease losses in the diode and to decrease the voltage stress at switch and also helps in creating the absence of problem of reverse recovery diodes. There are many research actions going on among them, these coupled-inductor boost converter already got a lot of priority, and they are known to be the best option for the case of high step-up applications. There is only one switch is being used in this converter and this switch is basically controlled under the condition called Zero Current Switching (ZCS), as it contains diodes. The percentage of voltage stain at the point of transfer is generally less than the voltage at the output. So, builds up conversion performance above 95%.
TL;DR: The magnetizing inductor of the transformer is designed to help the secondary side switches to achieve boundary zero voltage switching (ZVS) by analyzing the root mean square value of the leakage inductor current.
Abstract: In this article, a dual active bridge (DAB) based single-stage isolated ac–dc converter is studied. By analyzing the root mean square value of the leakage inductor current, the high-frequency transformer turns ratio is optimized for higher conversion efficiency. Three operating modes of the DAB converter are utilized in the control strategy. The current and the voltage waveforms of these operating modes are analyzed. The control variables, including the phase-shift ratio ϕ , the primary side duty cycle d 1, and the secondary side duty cycle d 2 are combined based on instantaneous calculation according to achieve boundary zero voltage switching (ZVS). The mode transition is seamless while the switching frequency is constant. Furthermore, the magnetizing inductor of the transformer is designed to help the secondary side switches to achieve ZVS. ZVS conditions and parameter design are given in this article. Besides, a 1 kW prototype was fabricated to verify the effectiveness of the design and the control strategy.