During wireless charging,misalignments commonly occur in the transmission between the transmitting and receiving pads,including misalignments in the forward,backward,lateral and vertical directions.Unavoidable misalig...During wireless charging,misalignments commonly occur in the transmission between the transmitting and receiving pads,including misalignments in the forward,backward,lateral and vertical directions.Unavoidable misalignments can result in changes in system parameters,thus affecting charging performance.A novel diagonally crossed solenoid magnetic coupler(DCSMC)is developed as a solution.The DCSMC integrated into a wireless power transfer(WPT)system with a hybrid topology enables superior misalignment tolerance in the X,Y,Zand XYdiagonal directionswhile maintaining load-independent voltage output characteristics.A simplified parameter design method is developed to optimize the misalignment tolerance performance of a hybrid WPT system in multiple directions.Finally,a hardware prototype of a WPT system is constructed with an operating frequency of 200kHz and a power of 200W.The experimental results showthat the hybrid WPT system,operating under loads from 40Ωto 80Ω,can tolerate misalignments of±90mm(40.9%)in both the Xand Yaxes,maintaining as small as a 5%fluctuation in output voltage.In addition,the WPT system can handle a maximum vertical displacement of+40mm along the Z-axis and XY-diagonal misalignments of±40mm(12.8%).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
In the contemporary energy landscape,the transition from traditional power grids to smart grids is being increasingly facilitated by the real-time monitoring,protection,and control capabilities provided by wide-area m...In the contemporary energy landscape,the transition from traditional power grids to smart grids is being increasingly facilitated by the real-time monitoring,protection,and control capabilities provided by wide-area measurement systems.The core of this evolution is the synchrophasor technology,which provides time-synchronized phasor measurements(an essential component for the successful implementation of smart grids).These phasor measurements are acquired through advanced,rapid,time-stamped devices known as phasor measurement units(PMUs),which play a pivotal role in enhancing grid reliability and efficiency.PMUs providehigh accuracy and precision in capturing electric phasors.This advancement has significantly contributed to the reliability of power systems.The data obtained from the PMUs can be applied across a diverse range of contexts and categorized according to their time criticality requirements.Furthermore,the applications can be classified according to their operational foci.A comprehensive review of the pivotal role of PMUs within the context of smart grid systems is presented.It systematically addresses the following key areas:the significance of real-time monitoring and control facilitated by PMUs in smart grids,contribution of PMUs to enhanced situational awareness,utilization of PMU data for state estimation applications,and critical function of PMUs in accurately identifying faults and their locations within the smart grid infrastructure.Additionally,PMU data management is explored.The focus here is on the processes of data acquisition and transmission enabled by PMUs in smart grids and the relevant communication technologies and protocols employed.This study aims to highlight the integral role of PMUs in optimizing the performance and reliability of smart grid networks.展开更多
In today’s fast-paced,information-driven world,data centers can offer high-speed,intricate capabilities on a larger scale owing to the ever-growing demand for networks and information systems.Because data centers pro...In today’s fast-paced,information-driven world,data centers can offer high-speed,intricate capabilities on a larger scale owing to the ever-growing demand for networks and information systems.Because data centers process and transmit information,stability and reliability are important.Data center power supply architectures rely heavily on isolated bidirectional DC-DC converters to ensure safety and stability.For the smooth operation of a data center,the power supply must be reliable and uninterrupted.In this study,we summarize the basic principle,topology,switch conversion strategy,and control technology of the existing isolated bidirectional DC-DC converters.Subsequently,existing research results and problems with isolated bidirectional DC-DC converters are reviewed.Finally,future trends in the development of isolated bidirectional DC-DC converters for data centers are presented,which offer valuable insights for solving engineering obstacles and future research directions in the field.展开更多
Modern eco-friendly industries such as renewable energy systems,electric vehicles(EVs),and light-emitting diodes(LEDs)have led to technological advancements in power electronics.Switching-based power converters have l...Modern eco-friendly industries such as renewable energy systems,electric vehicles(EVs),and light-emitting diodes(LEDs)have led to technological advancements in power electronics.Switching-based power converters have limited working ranges and can cause significant harmonics and oscillations in the output voltage and current.Introducing variable inductors can help solve this problem by changing the inductance without resorting to extreme switch duty cycles.Despite their advantages,there is still a lack of comprehensive reviews of variable inductor applications in power converter design.A thorough and in-depth review of variable inductance control in power conversion is presented,including its significance,working principle,core structure,modeling method,and typical applications.Traditionally,an inductor works in its linear magnetic region;its inductance in a power converter is considered constant,and the converter operates under fixed working conditions.However,a broad range of working conditions is required for power converters in practical applications.This is typically realized by changing the duty cycles of the switches.The working principle of variable inductance is reviewed,and the application of variable inductance control in power converters is presented,which will further help power electronics researchers and engineers design flexible and resilient power converters.展开更多
基金Supported by the Guangdong Basic and Applied Basic Research Foundation(2023A1515240033)the Basic and Applied Basic Research Foundation of Guangzhou(2024A04J6540)the Natural Science Foundation for Distinguished Young Scholars of Guangdong Province(2022B1515020002).
文摘During wireless charging,misalignments commonly occur in the transmission between the transmitting and receiving pads,including misalignments in the forward,backward,lateral and vertical directions.Unavoidable misalignments can result in changes in system parameters,thus affecting charging performance.A novel diagonally crossed solenoid magnetic coupler(DCSMC)is developed as a solution.The DCSMC integrated into a wireless power transfer(WPT)system with a hybrid topology enables superior misalignment tolerance in the X,Y,Zand XYdiagonal directionswhile maintaining load-independent voltage output characteristics.A simplified parameter design method is developed to optimize the misalignment tolerance performance of a hybrid WPT system in multiple directions.Finally,a hardware prototype of a WPT system is constructed with an operating frequency of 200kHz and a power of 200W.The experimental results showthat the hybrid WPT system,operating under loads from 40Ωto 80Ω,can tolerate misalignments of±90mm(40.9%)in both the Xand Yaxes,maintaining as small as a 5%fluctuation in output voltage.In addition,the WPT system can handle a maximum vertical displacement of+40mm along the Z-axis and XY-diagonal misalignments of±40mm(12.8%).
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.
文摘In the contemporary energy landscape,the transition from traditional power grids to smart grids is being increasingly facilitated by the real-time monitoring,protection,and control capabilities provided by wide-area measurement systems.The core of this evolution is the synchrophasor technology,which provides time-synchronized phasor measurements(an essential component for the successful implementation of smart grids).These phasor measurements are acquired through advanced,rapid,time-stamped devices known as phasor measurement units(PMUs),which play a pivotal role in enhancing grid reliability and efficiency.PMUs providehigh accuracy and precision in capturing electric phasors.This advancement has significantly contributed to the reliability of power systems.The data obtained from the PMUs can be applied across a diverse range of contexts and categorized according to their time criticality requirements.Furthermore,the applications can be classified according to their operational foci.A comprehensive review of the pivotal role of PMUs within the context of smart grid systems is presented.It systematically addresses the following key areas:the significance of real-time monitoring and control facilitated by PMUs in smart grids,contribution of PMUs to enhanced situational awareness,utilization of PMU data for state estimation applications,and critical function of PMUs in accurately identifying faults and their locations within the smart grid infrastructure.Additionally,PMU data management is explored.The focus here is on the processes of data acquisition and transmission enabled by PMUs in smart grids and the relevant communication technologies and protocols employed.This study aims to highlight the integral role of PMUs in optimizing the performance and reliability of smart grid networks.
基金Supported by the Natural Science Foundation for Distinguished Young Scholars of Guangdong Province(2022B1515020002).
文摘In today’s fast-paced,information-driven world,data centers can offer high-speed,intricate capabilities on a larger scale owing to the ever-growing demand for networks and information systems.Because data centers process and transmit information,stability and reliability are important.Data center power supply architectures rely heavily on isolated bidirectional DC-DC converters to ensure safety and stability.For the smooth operation of a data center,the power supply must be reliable and uninterrupted.In this study,we summarize the basic principle,topology,switch conversion strategy,and control technology of the existing isolated bidirectional DC-DC converters.Subsequently,existing research results and problems with isolated bidirectional DC-DC converters are reviewed.Finally,future trends in the development of isolated bidirectional DC-DC converters for data centers are presented,which offer valuable insights for solving engineering obstacles and future research directions in the field.
基金Supported by Natural Science Foundation for Distinguished Young Scholars of Guangdong Province under No.2022B1515020002。
文摘Modern eco-friendly industries such as renewable energy systems,electric vehicles(EVs),and light-emitting diodes(LEDs)have led to technological advancements in power electronics.Switching-based power converters have limited working ranges and can cause significant harmonics and oscillations in the output voltage and current.Introducing variable inductors can help solve this problem by changing the inductance without resorting to extreme switch duty cycles.Despite their advantages,there is still a lack of comprehensive reviews of variable inductor applications in power converter design.A thorough and in-depth review of variable inductance control in power conversion is presented,including its significance,working principle,core structure,modeling method,and typical applications.Traditionally,an inductor works in its linear magnetic region;its inductance in a power converter is considered constant,and the converter operates under fixed working conditions.However,a broad range of working conditions is required for power converters in practical applications.This is typically realized by changing the duty cycles of the switches.The working principle of variable inductance is reviewed,and the application of variable inductance control in power converters is presented,which will further help power electronics researchers and engineers design flexible and resilient power converters.
