The direct current-direct current （DC-DC） converter is designed for 1 T static random access memory （SRAM） used in display driver integrated circuits （ICs）, which consists of positive word-line voltage （VpwL）,...The direct current-direct current （DC-DC） converter is designed for 1 T static random access memory （SRAM） used in display driver integrated circuits （ICs）, which consists of positive word-line voltage （VpwL）, negative word-line voltage （VinyL） and half-VDD voltage （VHDo） generator. To generate a process voltage temperature （PVT）-insensitive VpWL and VNWL, a set of circuits were proposed to generate reference voltages using bandgap reference current generators for respective voltage level detectors. Also, a VOWL regulator and a VNWL charge pump were proposed for a small-area and low-power design. The proposed VpwL regulator can provide a large driving current with a small area since it regulates an input voltage （VCI） from 2.5 to 3.3 V. The VmvL charge pump can be implemented as a high-efficiency circuit with a small area and low power since it can transfer pumped charges to VNWL node entirely. The DC-DC converter for 1 T SRAM were designed with 0.11 μm mixed signal process and operated well with satisfactory measurement results.展开更多
针对直流微电网中储能系统功率波动、负载侧负荷频繁投切等不确定因素引起母线电压产生波动的问题,以储能系统中三相交错并联双向DC-DC变换器为研究对象,提出一种基于级联有限时间扩张状态观测器(cascade finite-time extended state ob...针对直流微电网中储能系统功率波动、负载侧负荷频繁投切等不确定因素引起母线电压产生波动的问题,以储能系统中三相交错并联双向DC-DC变换器为研究对象,提出一种基于级联有限时间扩张状态观测器(cascade finite-time extended state observer,CFT-ESO)的微分平坦和改进型超螺旋滑模双闭环复合控制策略.首先,建立三相交错并联双向DC-DC变换器的数学模型,并根据微分平坦理论将其直流系统转化为微分平坦系统,结合两级具有快速收敛性的有限时间扩张状态观测器提高对系统集总扰动的估计精度.其次,采用内环微分平坦控制、外环改进型超螺旋滑模控制的双闭环控制系统,既能提高系统动态响应过程,又能利用高阶滑模控制算法抑制抖振,同时解决变换器升压模式中非最小相位问题.再次,通过Lyapunov理论证明控制系统的稳定性.最后,利用MATLAB/Simulink仿真软件以及搭建实验平台对控制策略进行验证,结果表明,本文所提控制策略能够很好地抵抗扰动,提高系统的暂态性能.展开更多
The multi-string LED in parallel is a popular structure in backlight and lighting applications.The current balancing for each string is required to achieve uniform luminance and reliable operation.The conventional act...The multi-string LED in parallel is a popular structure in backlight and lighting applications.The current balancing for each string is required to achieve uniform luminance and reliable operation.The conventional active current sharing technique using a switching converter or a linear switch is very complex,and needs extra components.The conventional coupled inductor based current sharing method is much more simple,but needs too many coupled inductors.展开更多
In the modern wireless communication system,the manipulation for polarization of electromagnetic wave plays a important role in improving the capacity and reliability of communication.In this paper,a multifunctional p...In the modern wireless communication system,the manipulation for polarization of electromagnetic wave plays a important role in improving the capacity and reliability of communication.In this paper,a multifunctional polarization converter(MFPC)based on the multilayer reconfigurable metasurface is proposed,which can assist the source antenna to transmit and receive multiple polarization signals.The MFPC consists of a grating which can filter out the undesired polarization and four layers of metasurfaces incorporated with PIN diodes.The functions of the MFPC include LTC and LTL polarization conversions,co-polarization transmission and reflection for arbitrary polarization.By changing the states of PIN diodes,the functions of MFPC can be dynamically switched.Loaded on the aperture of source antenna,the proposed MFPC can serve as a transmissive array with multiple polarization channels,and can also provide EM protection for source antenna by reflecting the incoming interference waves.Cascading of the metasurfaces produces Fabry-Perot resonance in the MFPC,and it contributes to the realization of LTC and LTL polarization conversions.To verify the performance of the proposed MFPC,the prototype is fabricated and tested.The measured results show that the fractional bandwidths of four functions are all higher than 31.9% with transmission or reflection coefficients higher than-2 d B.The frequency band of each function is mainly concentrated in S-band.The measured data are in agreement with the simulated results.展开更多
Matrix Converter(MC),a direct AC-ACconverter which is capable of bidirectional powerflow,unity input power factor control and efficiencyimprovement.Thus,it is more suitable for integrationof motor machine and power el...Matrix Converter(MC),a direct AC-ACconverter which is capable of bidirectional powerflow,unity input power factor control and efficiencyimprovement.Thus,it is more suitable for integrationof motor machine and power electronics systems.This paper investigated a novel generationsystem,which is composed of hybrid excitedsynchronous generator(HESG)and matrix converter(MC),as shown in Fig.1.Owing to the voltage clampcircuit,this structure waived an external DC sourcecommonly used for the excitation for HESG.Thevoltage clamp circuit shared a DC bus with afull-bridge converter and the excitation winding ofHESG is directly connected to the output of thefull-bridge converter achieving a bidirectional currentflow.展开更多
基金supported by the Second Stage of Brain Korea 21 Projectsfinancially supported by Changwon National University in 2011-2013
文摘The direct current-direct current （DC-DC） converter is designed for 1 T static random access memory （SRAM） used in display driver integrated circuits （ICs）, which consists of positive word-line voltage （VpwL）, negative word-line voltage （VinyL） and half-VDD voltage （VHDo） generator. To generate a process voltage temperature （PVT）-insensitive VpWL and VNWL, a set of circuits were proposed to generate reference voltages using bandgap reference current generators for respective voltage level detectors. Also, a VOWL regulator and a VNWL charge pump were proposed for a small-area and low-power design. The proposed VpwL regulator can provide a large driving current with a small area since it regulates an input voltage （VCI） from 2.5 to 3.3 V. The VmvL charge pump can be implemented as a high-efficiency circuit with a small area and low power since it can transfer pumped charges to VNWL node entirely. The DC-DC converter for 1 T SRAM were designed with 0.11 μm mixed signal process and operated well with satisfactory measurement results.
文摘针对直流微电网中储能系统功率波动、负载侧负荷频繁投切等不确定因素引起母线电压产生波动的问题,以储能系统中三相交错并联双向DC-DC变换器为研究对象,提出一种基于级联有限时间扩张状态观测器(cascade finite-time extended state observer,CFT-ESO)的微分平坦和改进型超螺旋滑模双闭环复合控制策略.首先,建立三相交错并联双向DC-DC变换器的数学模型,并根据微分平坦理论将其直流系统转化为微分平坦系统,结合两级具有快速收敛性的有限时间扩张状态观测器提高对系统集总扰动的估计精度.其次,采用内环微分平坦控制、外环改进型超螺旋滑模控制的双闭环控制系统,既能提高系统动态响应过程,又能利用高阶滑模控制算法抑制抖振,同时解决变换器升压模式中非最小相位问题.再次,通过Lyapunov理论证明控制系统的稳定性.最后,利用MATLAB/Simulink仿真软件以及搭建实验平台对控制策略进行验证,结果表明,本文所提控制策略能够很好地抵抗扰动,提高系统的暂态性能.
文摘The multi-string LED in parallel is a popular structure in backlight and lighting applications.The current balancing for each string is required to achieve uniform luminance and reliable operation.The conventional active current sharing technique using a switching converter or a linear switch is very complex,and needs extra components.The conventional coupled inductor based current sharing method is much more simple,but needs too many coupled inductors.
基金supported in part by the Joint Funds of the National Natural Science Foundation of China(G02)(Grant No.U1834203)in part by of the Science and Technology Department of Sichuan Province(S01)(Grant No.2020JDTD0009)。
文摘In the modern wireless communication system,the manipulation for polarization of electromagnetic wave plays a important role in improving the capacity and reliability of communication.In this paper,a multifunctional polarization converter(MFPC)based on the multilayer reconfigurable metasurface is proposed,which can assist the source antenna to transmit and receive multiple polarization signals.The MFPC consists of a grating which can filter out the undesired polarization and four layers of metasurfaces incorporated with PIN diodes.The functions of the MFPC include LTC and LTL polarization conversions,co-polarization transmission and reflection for arbitrary polarization.By changing the states of PIN diodes,the functions of MFPC can be dynamically switched.Loaded on the aperture of source antenna,the proposed MFPC can serve as a transmissive array with multiple polarization channels,and can also provide EM protection for source antenna by reflecting the incoming interference waves.Cascading of the metasurfaces produces Fabry-Perot resonance in the MFPC,and it contributes to the realization of LTC and LTL polarization conversions.To verify the performance of the proposed MFPC,the prototype is fabricated and tested.The measured results show that the fractional bandwidths of four functions are all higher than 31.9% with transmission or reflection coefficients higher than-2 d B.The frequency band of each function is mainly concentrated in S-band.The measured data are in agreement with the simulated results.
文摘Matrix Converter(MC),a direct AC-ACconverter which is capable of bidirectional powerflow,unity input power factor control and efficiencyimprovement.Thus,it is more suitable for integrationof motor machine and power electronics systems.This paper investigated a novel generationsystem,which is composed of hybrid excitedsynchronous generator(HESG)and matrix converter(MC),as shown in Fig.1.Owing to the voltage clampcircuit,this structure waived an external DC sourcecommonly used for the excitation for HESG.Thevoltage clamp circuit shared a DC bus with afull-bridge converter and the excitation winding ofHESG is directly connected to the output of thefull-bridge converter achieving a bidirectional currentflow.
