A multi-phase stacked interleaved buck converter(SIBC)is suitable for large-power water electrolysis applications due to its merits of high current output capability and zero output current ripple.However,the auxiliar...A multi-phase stacked interleaved buck converter(SIBC)is suitable for large-power water electrolysis applications due to its merits of high current output capability and zero output current ripple.However,the auxiliary converter used to compensate for the current ripple still has to withstand high voltage stress.This paper proposes a new multi-phase SIBC applied in the multicarrier energy system integrating electricity,heat,and hydrogen.A resistor-capacitor voltage divider is used to provide the input voltage of the auxiliary converter and as a heater for the thermal loads.Thus,the voltage stress of the auxiliary converter can be reduced at a low cost,and the size of the filter inductor can be reduced.With accurate voltage and current analysis and appropriate parameter design,the voltage stresses of both the switches and capacitors in the auxiliary converter can be further limited within an expected range.The experimental results verify the correctness of the topology,modulation,analysis,and design methods.A comparison with the conventional method is made in terms of cost,volume,and efficiency to show the advantages of the proposed method.展开更多
Design method of split planar resonant inductor in 1 kV SiC logical link control(LLC)converter is proposed,which ensures the converter power density of 93.59 W/in^3 and peak efficiency of 95.73%.Split resonant inducto...Design method of split planar resonant inductor in 1 kV SiC logical link control(LLC)converter is proposed,which ensures the converter power density of 93.59 W/in^3 and peak efficiency of 95.73%.Split resonant inductor helps to provide symmetrical resonant current by symmetrical impedance,and improves the distortion of resonant current,which ensures the efficiency of the whole converter.An interleaved winding connecting scheme improves the power density of the planar magnets,which contributes to power density improvement.Design method and calculation process of such split planar resonant inductor are provided.To verify the feasibility of the proposed design method,a 1 kV/48 V 6.6 kW,210 k Hz SiC LLC prototype was built,and the experimental results are given.展开更多
Let S be a family of binary sequences constructed from interleaved construction. The linear spans of binary sequences in S are studied in this paper. In order to achieve the largest linear span, a criterion is present...Let S be a family of binary sequences constructed from interleaved construction. The linear spans of binary sequences in S are studied in this paper. In order to achieve the largest linear span, a criterion is presented for the base sequences with periodp, where p is a prime and 2 is a primitive root modulop2. It is shown that any sequence in S has the largest linear span under the criterion. Moreover, such base sequences can be chosen easily.展开更多
For communication systems with heavy burst noise, an optimal Forward Error Correction(FEC) scheme is expected to have a large burst error correction capability while simultaneously owning moderate random error correct...For communication systems with heavy burst noise, an optimal Forward Error Correction(FEC) scheme is expected to have a large burst error correction capability while simultaneously owning moderate random error correction capability. This letter presents a new FEC scheme based on multiple-symbol interleaved Reed-Solomon codes and an associated two-pass decoding algorithm. It is shown that the proposed multi-symbol interleaved Reed-Solomon scheme can achieve nearly twice as much as the burst error correction capability of conventional single-symbol interleaved Reed-Solomon codes with the same code length and code rate.展开更多
This work focuses on the fuzzy controller for the proposed three-phase interleaved Step-up converter(ISC).The fuzzy controller for the proposed ISC converters for electric vehicles has been discussed in detail.The pro...This work focuses on the fuzzy controller for the proposed three-phase interleaved Step-up converter(ISC).The fuzzy controller for the proposed ISC converters for electric vehicles has been discussed in detail.The proposed ISC direct current(DC-DC)converter could also be used in automobiles,satellites,industries,and propulsion.To enhance voltage gain,the proposed ISC Converter combines boost converter and interleaved converter(IC).This design also reduces the number of switches.As a result,ISC converter switching losses are reduced.The proposed ISC Converter topology can produce a 143 V output voltage and 1 kW of power.Due to the high voltage gain of this converter design,it is suitable for medium and high-power systems.The proposed ISC Converter topology is simulated in MATLAB/Simulink.The simulated output displays a high output voltage.But the output voltage contains maximum ripples.Fuzzy proposes an ISC Converter which makes closed loop responsiveness and reduces the output voltage ripple.The proposed ISC converter has the lowest ripple output voltage,which is less than 2%,because the duty cycle is regulated using the fuzzy logic controller.It offers high voltage gain,minimal ripple,and low switching loss.The performance of the proposed converter is compared to that of the fuzzy and Pro-portional Integral(PI)controllers implemented in MATLAB.展开更多
The generation of electricity based on renewable energy sources,parti-cularly Photovoltaic(PV)system has been greatly increased and it is simply insti-gated for both domestic and commercial uses.The power generated fr...The generation of electricity based on renewable energy sources,parti-cularly Photovoltaic(PV)system has been greatly increased and it is simply insti-gated for both domestic and commercial uses.The power generated from the PV system is erratic and hence there is a need for an efficient converter to perform the extraction of maximum power.An improved interleaved Single-ended Primary Inductor-Converter(SEPIC)converter is employed in proposed work to extricate most of power from renewable source.This proposed converter minimizes ripples,reduces electromagnetic interference due tofilter elements and the contin-uous input current improves the power output of PV panel.A Crow Search Algo-rithm(CSA)based Proportional Integral(PI)controller is utilized for controlling the converter switches effectively by optimizing the parameters of PI controller.The optimized PI controller reduces ripples present in Direct Current(DC)vol-tage,maintains constant voltage at proposed converter output and reduces over-shoots with minimum settling and rise time.This voltage is given to single phase grid via 1�Voltage Source Inverter(VSI).The command pulses of 1�VSI are produced by simple PI controller.The response of the proposed converter is thus improved with less input current.After implementing CSA based PI the efficiency of proposed converter obtained is 96%and the Total Harmonic Distor-tion(THD)is found to be 2:4%.The dynamics and closed loop operation is designed and modeled using MATLAB Simulink tool and its behavior is performed.展开更多
Parallel converter can significantly increase the capacity of the converter and improve the power quality of AC side, but the circulation which can lead to high switching loss and even damage the devices will easily e...Parallel converter can significantly increase the capacity of the converter and improve the power quality of AC side, but the circulation which can lead to high switching loss and even damage the devices will easily exist in the direct parallel converters. In this paper, the average model of parallel interleaved inverters system to analyze the circulation current is shown, and the cross current is relevant to DC-bus voltage and the overlap time of zero vectors in the switching period. Based on this observation, a discontinuous space vector modulation without using zero vectors (000) is eliminate and suppress the zero-sequence current to entire system. Finally, the effectiveness of modulation strategy is verified by the simulations in this paper.展开更多
Taking Jiuhong Modern Agriculture Demonstration Park of Heilongjiang Province as the base for rice disease image acquisition,a total of 841 images of the four different diseases,including rice blast,stripe leaf blight...Taking Jiuhong Modern Agriculture Demonstration Park of Heilongjiang Province as the base for rice disease image acquisition,a total of 841 images of the four different diseases,including rice blast,stripe leaf blight,red blight and bacterial brown spot,were obtained.In this study,an interleaved attention neural network(IANN)was proposed to realize the recognition of rice disease images and an interleaved group convolutions(IGC)network was introduced to reduce the number of convolutional parameters,which realized the information interaction between channels.Based on the convolutional block attention module(CBAM),attention was paid to the features of results of the primary group convolution in the cross-group convolution to improve the classification performance of the deep learning model.The results showed that the classification accuracy of IANN was 96.14%,which was 4.72%higher than that of the classical convolutional neural network(CNN).This study showed a new idea for the efficient training of neural networks in the case of small samples and provided a reference for the image recognition and diagnosis of rice and other crop diseases.展开更多
In this paper, we propose the receiver structure for Multiple Input Multiple Output (MIMO) Interleaved Single Carrier-Frequency Division Multiple Access (SC-FDMA) where the Frequency Domain Equalization (FDE) is first...In this paper, we propose the receiver structure for Multiple Input Multiple Output (MIMO) Interleaved Single Carrier-Frequency Division Multiple Access (SC-FDMA) where the Frequency Domain Equalization (FDE) is firstly done for obtaining the tentative decision results and secondly using them the Inter-Symbol Interference (ISI) is cancelled by ISI canceller and then the Maximum Likelihood Detection (MLD) is used for separating the spatially multiplexed signals. Furthermore the output from MLD is fed back to ISI canceller repeatedly. In order to reduce the complexity, we replace the MLD by QR Decomposition with M-Algorithm (QRD-M) or Sphere Decoding (SD). Moreover, we add the soft output function to SD using Repeated Tree Search (RTS) algorithm to generate soft replica for ISI cancellation. We also refer to the Single Tree Search (STS) algorithm to further reduce the complexity of RTS. By examining the BER characteristics and the complexity reduction through computer simulations, we have verified the effectiveness of proposed receiver structure.展开更多
Interfacing DC sources to load/power grid requires DC converters that produce minimum level of current ripples. This is to limit the losses and hence increase the life span of these sources. This article proposes a si...Interfacing DC sources to load/power grid requires DC converters that produce minimum level of current ripples. This is to limit the losses and hence increase the life span of these sources. This article proposes a simple inter-leaved boost converter that interfaces PhotoVoltaic (PV) module into a common DC-link. The article also addresses the faulty mode operation of the proposed circuit while advising the appropriate remedy actions. A MATLAB and Simulink dynamic platform are used to simulate the transient performance of the proposed converter. The results revealed the effectiveness and the viability of the proposed converter in reducing the ripples in the PV current without employing bulky input inductors or increasing the switching frequency.展开更多
Today, energy saving is one of the main objectives for engineers. In the case of mobile applications, energy can be saved by two different ways： decreasing the total masse of the system and increasing the efficiency ...Today, energy saving is one of the main objectives for engineers. In the case of mobile applications, energy can be saved by two different ways： decreasing the total masse of the system and increasing the efficiency of the overall system. This paper presents two optimization strategies to design a predefined multichannel structure of a boost converter which is dedicated to a solar airplane and used to interface PV panels and the battery system. The first strategy is a multi-criterion method that is able to trace the dependency between the converter＇s efficiency and its power density through the intermediary of the Pareto front. The second method, a mono-criterion approach, maximizes efficiency while respecting the constraint imposed on power density. The mono-criterion method that is applied to maximizing the European efficiency criterion showed that an increase in the number of channels enhanced the quantity of energy collected over a day by increasing the power density of the converter. At the end of the paper, the optimal design calculated was built to give an example of the result obtained by this design methodology. The results of the efficiency measurements made on a realized prototype are presented in this paper.展开更多
This paper proposes the design and experimentation of digital control of soft-switched interleaved boost converter using FPGA for Telecommunication System. The switching devices in the proposed converter are turned on...This paper proposes the design and experimentation of digital control of soft-switched interleaved boost converter using FPGA for Telecommunication System. The switching devices in the proposed converter are turned on and off with Zero Voltage Switching (ZVS) and Zero Current Switching (ZCS) respectively. The circuit is operated in Continuous Conduction Mode (CCM) with various load ranges having duty cycle of more than 50%. The proposed converter is studied by developing the simulation module in MATLAB/SIMULINK. A PI controller is designed and implemented in FPGA to obtain a regulated DC output for line and load variations. Simulation and experimentation results are verified with a prototype development of the proposed converter. The results indicate that the converter performance is enhanced with closed loop control.展开更多
Herein,we report the preparation of well characterized hierarchical CuO/ZnO heterostructures and demonstrate the versatility of this composite as a CO_(2)gas sensor and a visible light catalyst for methylene blue(MB)d...Herein,we report the preparation of well characterized hierarchical CuO/ZnO heterostructures and demonstrate the versatility of this composite as a CO_(2)gas sensor and a visible light catalyst for methylene blue(MB)degradation.3D hierarchical ZnO spheres were decorated with CuO nanoleaves to form the interleaved p-CuO/n-ZnO hetero-surfaces.Subsequently,silver(Ag)functionalized composites were tested for their sensitivity and selectivity towards CO_(2)gas as a core application.展开更多
In microwave communication systems,focusing and imaging have attracted widespread attention due to their application prospects in the information processing and communication fields.Most existing multi-channel focusin...In microwave communication systems,focusing and imaging have attracted widespread attention due to their application prospects in the information processing and communication fields.Most existing multi-channel focusing and imaging are implemented by interleaved metasurfaces.However,the disadvantages of their large size and low efficiency limit their practical applications in large-capacity and low-loss integrated systems.To solve these issues,here,we propose a non-interleaved polarization-frequency multiplexing metasurface for high-efficiency multi-channel focusing and imaging.The meta-atoms of the non-interleaved metasurface are composed of a metallic ground plate,two dielectric layers,a larger cross-shaped metal structure,and a smaller cross-shaped metal structure embedded by a circular metal aperture.By altering the size of two cross-shaped structures,the designed meta-atom can obtain the independent complete 2π phase coverage with high reflection efficiency at two different frequency ranges for two orthogonal linear polarization(LP)incidences,realizing polarization multiplexing and frequency multiplexing.Moreover,two types of metasurfaces based on the above meta-atoms are designed to realize multi-channel focusing and imaging with high efficiency.As a proof,the focusing metasurface is fabricated and measured,and the measured results are well consistent with simulated results.Therefore,the proposed scheme has the advantages of high efficiency,multi-channel,and compact size,which possesses broad application prospects in low-loss and multichannel communication integrated systems.展开更多
High-performance microprocessors have rapidlyevolved and become ubiquitous in modern society.However,their power supply has become a significant factor limiting their overall performance.A power delivery module,known ...High-performance microprocessors have rapidlyevolved and become ubiquitous in modern society.However,their power supply has become a significant factor limiting their overall performance.A power delivery module,known as a voltage regulator module(VRM),is required to provide high voltage,low current,and a fast transient response to meet microprocessor demands.An interleaved parallel-buck converter is suitable for VRM applications.Selecting an appropriate control strategy for the interleaved converter can help achieve high precision and fast response,thereby optimizing performance.First,the operating principles of interleaved parallel converters are analyzed.The relationship between the number of phases and conversion efficiency is also examined.Subsequently,commonly employed control techniques for interleaved converters are reviewed,discussing their respective advantages and limitations,along with an analysis of their suitabilityfor phase-shedding strategies.A phase-shedding technique for interleaved converters is then introduced.Finally,the shortcomings of current control approaches for interleaved buck converters are outlined,and potential future research directions are suggested.These insights aim to enhance control performance and advance practical engineering applications.展开更多
Conventional fracture mechanics asserts that the relevant physics governing small crack growth occurs near the crack front.However,for fatigue,computing these physics for each crack-growth increment over the entire mi...Conventional fracture mechanics asserts that the relevant physics governing small crack growth occurs near the crack front.However,for fatigue,computing these physics for each crack-growth increment over the entire microstructurally small crack regime is computationally intractable.Properly trained deep-learning surrogate models canmassively accelerate fatigue crack-growth predictions by virtually propagating an initial crack using micromechanical fields corresponding to just the initially cracked microstructure.As the predicted crack front advances,however,the fields no longer reflect relevant near-crack-front physics,leading to error and uncertainty accumulation.To address this,we present an interleaved physics-based deep-learning(PBDL)framework,where updates to the crack representation in the physics-based model are triggered intermittently using model uncertainty,thereby updating micromechanical fields passed to the deep-learning model.We show that this framework,representing a novel cycle-jumping approach,effectively limits error accumulation in history-dependent fatigue crack evolution and forms a template for other time-series applications in materials.展开更多
In DC microgrid systems,interleaved boost converters(IBCs)are widely used to boost the output voltage of renewable energy sources on the source side of a DC bus owing to their high voltage gain and low current ripple....In DC microgrid systems,interleaved boost converters(IBCs)are widely used to boost the output voltage of renewable energy sources on the source side of a DC bus owing to their high voltage gain and low current ripple.However,because power electronic converters on the load side behave as constant power loads(CPLs)with negative impedance characteristics,their high penetration can degrade the system stability.Therefore,this article proposes a fractional-order nonlinear controller integrated with an extended nonlinear disturbance observer(ENDO)for N-phase IBCs.First,the reduced-order model of the IBC is transformed into a canonical form using the differential geometric method.Subsequently,with the ENDO,the dynamic performance can be enhanced by estimating the disturbances,and a fractional-order nonlinear sliding surface is established to avoid the singularity problem and increase control flexibility.In addition,the stability of the proposed controller is analyzed using Lyapunov’s theorem.In a CPL variation test,the proposed controller exhibited a faster dynamic performance and lower tracking error thanconventional controllers,with at least a 27%improvement in the integral squared error(ISE).Both simulation and experimental results demonstrated the effectivenessof the controller,which can ensure large-signal stability and improved dynamic performance in DC microgrid systems.展开更多
Battery energy storage systems bolster power grids’absorption capacity,however,battery safety issues remain a formidable challenge.Timely and pre-cise fault diagnosis,coupled with early-stage fault warn-ings,is cruci...Battery energy storage systems bolster power grids’absorption capacity,however,battery safety issues remain a formidable challenge.Timely and pre-cise fault diagnosis,coupled with early-stage fault warn-ings,is crucial.This study introduces an eigen decompo-sition-based multi-fault diagnosis approach for lithi-umion battery packs,enabling online diagnosis of short circuits,electrical connection faults,and voltage sensor malfunctions.By incorporating an interleaved measurement topology,precise fault type differentiation is achieved.Eigenvector matching analysis is employed to increase sensitivity to fault characteristics and enhance robustness.The interleaved topology can be seamlessly integrated using common voltage measurement solutions,eliminating the need for additional design complexities,while sensor number redundancy enhances fault tolerance of battery management systems(BMS).A cloud-side collaboration method is proposed,where the BMS functions as an edge device for specific data computations,while the parameters are fine-tuned by the server through big data analytics.This approach circumvents cumbersome server calculations,thereby curbing server cost escalation.The edge computing process is divided into two steps,with partial calculations often sufficient to evaluate battery safety,thus reducing the computational load on edge devices.Several battery tests are conducted,and the results confirm the method’s capability,feasibility,and validity in early-stage fault diagnosis.展开更多
Optical metasurfaces,comprising subwavelength quasi-planar nanostructures,constitute a universal platform for manipulating the amplitude,phase,and polarization of light,thus paving a way for the next generation of hig...Optical metasurfaces,comprising subwavelength quasi-planar nanostructures,constitute a universal platform for manipulating the amplitude,phase,and polarization of light,thus paving a way for the next generation of highly integrated multifunctional optical devices.In this work,we introduce a reflective metasurface for the generation of a complete(angularly resolved)polarization set by randomly interleaving anisotropic plasmonic meta-atoms acting as nanoscale wave plates.In the proof-of-concept demonstration,we achieve multidirectional beam-steering into different polarization channels forming a complete set of polarization states,which can also be dynamically altered by switching the spin of incident light.The developed design concept represents a significant advancement in achieving flat polarization optics with advanced functionalities.展开更多
In the application of long series batteries,there is always the phenomenon that multiple cells in a pack are unbalanced simultaneously.In view of this situation,a modevarying cell equalizer topology based on interleav...In the application of long series batteries,there is always the phenomenon that multiple cells in a pack are unbalanced simultaneously.In view of this situation,a modevarying cell equalizer topology based on interleaved parallel multiple transformers is proposed in this paper.Every unit in this equalizer can freely switch between LLC resonance mode and 3-state LC quasi-resonance mode.The boosting effect of LLC structure is used to reduce the number of transformer’s total turns.When multiple equalizer units need to work in LLC mode simultaneously,interleaved parallel technology is used to limit secondary side equalization current ripple for long-term protection of battery life.A prototype was designed and built to validate the effect of a closed loop LLC mode control algorithm with a state-of-charge(SOC)based equalization scheme selection strategy.Experimental results including up to 88.52%efficiency in LLC mode with 90.7%efficiency in 3-state LC mode,and minute level balancing time show the proposed topology demonstrates excellent balancing performance.展开更多
基金supported in part by the National Natural Science Foundation of China(52077190)Cultivation Project for Basic Research and Innovation of Yanshan University(2021LGQN007)Science and Technology Project of Hebei Education Department(QN2024202).
文摘A multi-phase stacked interleaved buck converter(SIBC)is suitable for large-power water electrolysis applications due to its merits of high current output capability and zero output current ripple.However,the auxiliary converter used to compensate for the current ripple still has to withstand high voltage stress.This paper proposes a new multi-phase SIBC applied in the multicarrier energy system integrating electricity,heat,and hydrogen.A resistor-capacitor voltage divider is used to provide the input voltage of the auxiliary converter and as a heater for the thermal loads.Thus,the voltage stress of the auxiliary converter can be reduced at a low cost,and the size of the filter inductor can be reduced.With accurate voltage and current analysis and appropriate parameter design,the voltage stresses of both the switches and capacitors in the auxiliary converter can be further limited within an expected range.The experimental results verify the correctness of the topology,modulation,analysis,and design methods.A comparison with the conventional method is made in terms of cost,volume,and efficiency to show the advantages of the proposed method.
基金supported by the National Key Research and Development Program of China (2018YFB0904101)Science and Technology Project of State Grid (SG SGHB0000KXJS1800685)
文摘Design method of split planar resonant inductor in 1 kV SiC logical link control(LLC)converter is proposed,which ensures the converter power density of 93.59 W/in^3 and peak efficiency of 95.73%.Split resonant inductor helps to provide symmetrical resonant current by symmetrical impedance,and improves the distortion of resonant current,which ensures the efficiency of the whole converter.An interleaved winding connecting scheme improves the power density of the planar magnets,which contributes to power density improvement.Design method and calculation process of such split planar resonant inductor are provided.To verify the feasibility of the proposed design method,a 1 kV/48 V 6.6 kW,210 k Hz SiC LLC prototype was built,and the experimental results are given.
基金Supported by the National Natural Science Foundation ofChina (60573053 , 60603012)the Specialized Research Fund for the Doctoral Program of Higher Education of China (20050512002)
文摘Let S be a family of binary sequences constructed from interleaved construction. The linear spans of binary sequences in S are studied in this paper. In order to achieve the largest linear span, a criterion is presented for the base sequences with periodp, where p is a prime and 2 is a primitive root modulop2. It is shown that any sequence in S has the largest linear span under the criterion. Moreover, such base sequences can be chosen easily.
文摘For communication systems with heavy burst noise, an optimal Forward Error Correction(FEC) scheme is expected to have a large burst error correction capability while simultaneously owning moderate random error correction capability. This letter presents a new FEC scheme based on multiple-symbol interleaved Reed-Solomon codes and an associated two-pass decoding algorithm. It is shown that the proposed multi-symbol interleaved Reed-Solomon scheme can achieve nearly twice as much as the burst error correction capability of conventional single-symbol interleaved Reed-Solomon codes with the same code length and code rate.
文摘This work focuses on the fuzzy controller for the proposed three-phase interleaved Step-up converter(ISC).The fuzzy controller for the proposed ISC converters for electric vehicles has been discussed in detail.The proposed ISC direct current(DC-DC)converter could also be used in automobiles,satellites,industries,and propulsion.To enhance voltage gain,the proposed ISC Converter combines boost converter and interleaved converter(IC).This design also reduces the number of switches.As a result,ISC converter switching losses are reduced.The proposed ISC Converter topology can produce a 143 V output voltage and 1 kW of power.Due to the high voltage gain of this converter design,it is suitable for medium and high-power systems.The proposed ISC Converter topology is simulated in MATLAB/Simulink.The simulated output displays a high output voltage.But the output voltage contains maximum ripples.Fuzzy proposes an ISC Converter which makes closed loop responsiveness and reduces the output voltage ripple.The proposed ISC converter has the lowest ripple output voltage,which is less than 2%,because the duty cycle is regulated using the fuzzy logic controller.It offers high voltage gain,minimal ripple,and low switching loss.The performance of the proposed converter is compared to that of the fuzzy and Pro-portional Integral(PI)controllers implemented in MATLAB.
文摘The generation of electricity based on renewable energy sources,parti-cularly Photovoltaic(PV)system has been greatly increased and it is simply insti-gated for both domestic and commercial uses.The power generated from the PV system is erratic and hence there is a need for an efficient converter to perform the extraction of maximum power.An improved interleaved Single-ended Primary Inductor-Converter(SEPIC)converter is employed in proposed work to extricate most of power from renewable source.This proposed converter minimizes ripples,reduces electromagnetic interference due tofilter elements and the contin-uous input current improves the power output of PV panel.A Crow Search Algo-rithm(CSA)based Proportional Integral(PI)controller is utilized for controlling the converter switches effectively by optimizing the parameters of PI controller.The optimized PI controller reduces ripples present in Direct Current(DC)vol-tage,maintains constant voltage at proposed converter output and reduces over-shoots with minimum settling and rise time.This voltage is given to single phase grid via 1�Voltage Source Inverter(VSI).The command pulses of 1�VSI are produced by simple PI controller.The response of the proposed converter is thus improved with less input current.After implementing CSA based PI the efficiency of proposed converter obtained is 96%and the Total Harmonic Distor-tion(THD)is found to be 2:4%.The dynamics and closed loop operation is designed and modeled using MATLAB Simulink tool and its behavior is performed.
文摘Parallel converter can significantly increase the capacity of the converter and improve the power quality of AC side, but the circulation which can lead to high switching loss and even damage the devices will easily exist in the direct parallel converters. In this paper, the average model of parallel interleaved inverters system to analyze the circulation current is shown, and the cross current is relevant to DC-bus voltage and the overlap time of zero vectors in the switching period. Based on this observation, a discontinuous space vector modulation without using zero vectors (000) is eliminate and suppress the zero-sequence current to entire system. Finally, the effectiveness of modulation strategy is verified by the simulations in this paper.
基金Supported by the Heilongjiang Provincial Key Research and Development Program Guidance Project(GZ20210103)。
文摘Taking Jiuhong Modern Agriculture Demonstration Park of Heilongjiang Province as the base for rice disease image acquisition,a total of 841 images of the four different diseases,including rice blast,stripe leaf blight,red blight and bacterial brown spot,were obtained.In this study,an interleaved attention neural network(IANN)was proposed to realize the recognition of rice disease images and an interleaved group convolutions(IGC)network was introduced to reduce the number of convolutional parameters,which realized the information interaction between channels.Based on the convolutional block attention module(CBAM),attention was paid to the features of results of the primary group convolution in the cross-group convolution to improve the classification performance of the deep learning model.The results showed that the classification accuracy of IANN was 96.14%,which was 4.72%higher than that of the classical convolutional neural network(CNN).This study showed a new idea for the efficient training of neural networks in the case of small samples and provided a reference for the image recognition and diagnosis of rice and other crop diseases.
文摘In this paper, we propose the receiver structure for Multiple Input Multiple Output (MIMO) Interleaved Single Carrier-Frequency Division Multiple Access (SC-FDMA) where the Frequency Domain Equalization (FDE) is firstly done for obtaining the tentative decision results and secondly using them the Inter-Symbol Interference (ISI) is cancelled by ISI canceller and then the Maximum Likelihood Detection (MLD) is used for separating the spatially multiplexed signals. Furthermore the output from MLD is fed back to ISI canceller repeatedly. In order to reduce the complexity, we replace the MLD by QR Decomposition with M-Algorithm (QRD-M) or Sphere Decoding (SD). Moreover, we add the soft output function to SD using Repeated Tree Search (RTS) algorithm to generate soft replica for ISI cancellation. We also refer to the Single Tree Search (STS) algorithm to further reduce the complexity of RTS. By examining the BER characteristics and the complexity reduction through computer simulations, we have verified the effectiveness of proposed receiver structure.
文摘Interfacing DC sources to load/power grid requires DC converters that produce minimum level of current ripples. This is to limit the losses and hence increase the life span of these sources. This article proposes a simple inter-leaved boost converter that interfaces PhotoVoltaic (PV) module into a common DC-link. The article also addresses the faulty mode operation of the proposed circuit while advising the appropriate remedy actions. A MATLAB and Simulink dynamic platform are used to simulate the transient performance of the proposed converter. The results revealed the effectiveness and the viability of the proposed converter in reducing the ripples in the PV current without employing bulky input inductors or increasing the switching frequency.
文摘Today, energy saving is one of the main objectives for engineers. In the case of mobile applications, energy can be saved by two different ways： decreasing the total masse of the system and increasing the efficiency of the overall system. This paper presents two optimization strategies to design a predefined multichannel structure of a boost converter which is dedicated to a solar airplane and used to interface PV panels and the battery system. The first strategy is a multi-criterion method that is able to trace the dependency between the converter＇s efficiency and its power density through the intermediary of the Pareto front. The second method, a mono-criterion approach, maximizes efficiency while respecting the constraint imposed on power density. The mono-criterion method that is applied to maximizing the European efficiency criterion showed that an increase in the number of channels enhanced the quantity of energy collected over a day by increasing the power density of the converter. At the end of the paper, the optimal design calculated was built to give an example of the result obtained by this design methodology. The results of the efficiency measurements made on a realized prototype are presented in this paper.
文摘This paper proposes the design and experimentation of digital control of soft-switched interleaved boost converter using FPGA for Telecommunication System. The switching devices in the proposed converter are turned on and off with Zero Voltage Switching (ZVS) and Zero Current Switching (ZCS) respectively. The circuit is operated in Continuous Conduction Mode (CCM) with various load ranges having duty cycle of more than 50%. The proposed converter is studied by developing the simulation module in MATLAB/SIMULINK. A PI controller is designed and implemented in FPGA to obtain a regulated DC output for line and load variations. Simulation and experimentation results are verified with a prototype development of the proposed converter. The results indicate that the converter performance is enhanced with closed loop control.
基金acknowledge RMIT University,Australia,for financial assistance in the form of a postgraduate scholarship(CLP-0092).
文摘Herein,we report the preparation of well characterized hierarchical CuO/ZnO heterostructures and demonstrate the versatility of this composite as a CO_(2)gas sensor and a visible light catalyst for methylene blue(MB)degradation.3D hierarchical ZnO spheres were decorated with CuO nanoleaves to form the interleaved p-CuO/n-ZnO hetero-surfaces.Subsequently,silver(Ag)functionalized composites were tested for their sensitivity and selectivity towards CO_(2)gas as a core application.
基金National Natural Science Foundation of China(62075052,6227419)National Key Research and Development Program of China(2024YFE0108300)+2 种基金Science and Technology Major Project of Guangxi,China(Gui Ke AA21077015,Gui Ke AA24263032)Science Foundation of the National Key Laboratory of Science and Technology on Advanced Composites in Special Environments(JCKYS2020603C009,6142905212711)Project of Innovative and Entrepreneurship Training Program for College Students in Heilongjiang Province(201810214105)。
文摘In microwave communication systems,focusing and imaging have attracted widespread attention due to their application prospects in the information processing and communication fields.Most existing multi-channel focusing and imaging are implemented by interleaved metasurfaces.However,the disadvantages of their large size and low efficiency limit their practical applications in large-capacity and low-loss integrated systems.To solve these issues,here,we propose a non-interleaved polarization-frequency multiplexing metasurface for high-efficiency multi-channel focusing and imaging.The meta-atoms of the non-interleaved metasurface are composed of a metallic ground plate,two dielectric layers,a larger cross-shaped metal structure,and a smaller cross-shaped metal structure embedded by a circular metal aperture.By altering the size of two cross-shaped structures,the designed meta-atom can obtain the independent complete 2π phase coverage with high reflection efficiency at two different frequency ranges for two orthogonal linear polarization(LP)incidences,realizing polarization multiplexing and frequency multiplexing.Moreover,two types of metasurfaces based on the above meta-atoms are designed to realize multi-channel focusing and imaging with high efficiency.As a proof,the focusing metasurface is fabricated and measured,and the measured results are well consistent with simulated results.Therefore,the proposed scheme has the advantages of high efficiency,multi-channel,and compact size,which possesses broad application prospects in low-loss and multichannel communication integrated systems.
基金Supported by Guangdong Basic and Applied Basic Research Foundation(2023A1515240033)Basic and Applied Basic Research Foundation of Guangzhou(2024A04J6540)Guangdong Science Fund for Distinguished Young Scholars(2022B1515020002).
文摘High-performance microprocessors have rapidlyevolved and become ubiquitous in modern society.However,their power supply has become a significant factor limiting their overall performance.A power delivery module,known as a voltage regulator module(VRM),is required to provide high voltage,low current,and a fast transient response to meet microprocessor demands.An interleaved parallel-buck converter is suitable for VRM applications.Selecting an appropriate control strategy for the interleaved converter can help achieve high precision and fast response,thereby optimizing performance.First,the operating principles of interleaved parallel converters are analyzed.The relationship between the number of phases and conversion efficiency is also examined.Subsequently,commonly employed control techniques for interleaved converters are reviewed,discussing their respective advantages and limitations,along with an analysis of their suitabilityfor phase-shedding strategies.A phase-shedding technique for interleaved converters is then introduced.Finally,the shortcomings of current control approaches for interleaved buck converters are outlined,and potential future research directions are suggested.These insights aim to enhance control performance and advance practical engineering applications.
基金supported by the National Science Foundation under Grant No. CMMI-1752400. The authors would like to acknowledge the computational resources provided by the University of Utah's Center for High Performance Computing.
文摘Conventional fracture mechanics asserts that the relevant physics governing small crack growth occurs near the crack front.However,for fatigue,computing these physics for each crack-growth increment over the entire microstructurally small crack regime is computationally intractable.Properly trained deep-learning surrogate models canmassively accelerate fatigue crack-growth predictions by virtually propagating an initial crack using micromechanical fields corresponding to just the initially cracked microstructure.As the predicted crack front advances,however,the fields no longer reflect relevant near-crack-front physics,leading to error and uncertainty accumulation.To address this,we present an interleaved physics-based deep-learning(PBDL)framework,where updates to the crack representation in the physics-based model are triggered intermittently using model uncertainty,thereby updating micromechanical fields passed to the deep-learning model.We show that this framework,representing a novel cycle-jumping approach,effectively limits error accumulation in history-dependent fatigue crack evolution and forms a template for other time-series applications in materials.
基金Supported by the National Natural Science Foundation of China(52077085)Natural Science Foundation of Guangdong Province(2023A1515012273).
文摘In DC microgrid systems,interleaved boost converters(IBCs)are widely used to boost the output voltage of renewable energy sources on the source side of a DC bus owing to their high voltage gain and low current ripple.However,because power electronic converters on the load side behave as constant power loads(CPLs)with negative impedance characteristics,their high penetration can degrade the system stability.Therefore,this article proposes a fractional-order nonlinear controller integrated with an extended nonlinear disturbance observer(ENDO)for N-phase IBCs.First,the reduced-order model of the IBC is transformed into a canonical form using the differential geometric method.Subsequently,with the ENDO,the dynamic performance can be enhanced by estimating the disturbances,and a fractional-order nonlinear sliding surface is established to avoid the singularity problem and increase control flexibility.In addition,the stability of the proposed controller is analyzed using Lyapunov’s theorem.In a CPL variation test,the proposed controller exhibited a faster dynamic performance and lower tracking error thanconventional controllers,with at least a 27%improvement in the integral squared error(ISE).Both simulation and experimental results demonstrated the effectivenessof the controller,which can ensure large-signal stability and improved dynamic performance in DC microgrid systems.
基金supported in part by the National Natural Science Foundation of China(No.62133007)Shandong Provincial Key Research and Development Program(No.2024CXPT052).
文摘Battery energy storage systems bolster power grids’absorption capacity,however,battery safety issues remain a formidable challenge.Timely and pre-cise fault diagnosis,coupled with early-stage fault warn-ings,is crucial.This study introduces an eigen decompo-sition-based multi-fault diagnosis approach for lithi-umion battery packs,enabling online diagnosis of short circuits,electrical connection faults,and voltage sensor malfunctions.By incorporating an interleaved measurement topology,precise fault type differentiation is achieved.Eigenvector matching analysis is employed to increase sensitivity to fault characteristics and enhance robustness.The interleaved topology can be seamlessly integrated using common voltage measurement solutions,eliminating the need for additional design complexities,while sensor number redundancy enhances fault tolerance of battery management systems(BMS).A cloud-side collaboration method is proposed,where the BMS functions as an edge device for specific data computations,while the parameters are fine-tuned by the server through big data analytics.This approach circumvents cumbersome server calculations,thereby curbing server cost escalation.The edge computing process is divided into two steps,with partial calculations often sufficient to evaluate battery safety,thus reducing the computational load on edge devices.Several battery tests are conducted,and the results confirm the method’s capability,feasibility,and validity in early-stage fault diagnosis.
基金funded by the Danmarks Frie Forskningsfond(1134-00010B)Villum Fonden(Award in Technical and Natural Sciences 2019 and Grant No.37372)Y.Deng would like to acknowledge the support from the China Scholarship Council(Grant No.202108330079).
文摘Optical metasurfaces,comprising subwavelength quasi-planar nanostructures,constitute a universal platform for manipulating the amplitude,phase,and polarization of light,thus paving a way for the next generation of highly integrated multifunctional optical devices.In this work,we introduce a reflective metasurface for the generation of a complete(angularly resolved)polarization set by randomly interleaving anisotropic plasmonic meta-atoms acting as nanoscale wave plates.In the proof-of-concept demonstration,we achieve multidirectional beam-steering into different polarization channels forming a complete set of polarization states,which can also be dynamically altered by switching the spin of incident light.The developed design concept represents a significant advancement in achieving flat polarization optics with advanced functionalities.
基金supported in main part by the General Project of National Natural Science Foundation of China under Grant 61671194in part by the General Scientific Research Projects of Zhejiang Education Department under Grant Y201840464.
文摘In the application of long series batteries,there is always the phenomenon that multiple cells in a pack are unbalanced simultaneously.In view of this situation,a modevarying cell equalizer topology based on interleaved parallel multiple transformers is proposed in this paper.Every unit in this equalizer can freely switch between LLC resonance mode and 3-state LC quasi-resonance mode.The boosting effect of LLC structure is used to reduce the number of transformer’s total turns.When multiple equalizer units need to work in LLC mode simultaneously,interleaved parallel technology is used to limit secondary side equalization current ripple for long-term protection of battery life.A prototype was designed and built to validate the effect of a closed loop LLC mode control algorithm with a state-of-charge(SOC)based equalization scheme selection strategy.Experimental results including up to 88.52%efficiency in LLC mode with 90.7%efficiency in 3-state LC mode,and minute level balancing time show the proposed topology demonstrates excellent balancing performance.
