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采用峰值电感电流控制的直流-直流电压转换器
A DC??DC Converter Based on Inductor??Peak??Current Control
 [PDF]

熊齐,李尊朝,焦琛,周律忱
- , 2018, DOI: 10.7652/xjtuxb201812019
Abstract: 针对可穿戴设备需要小型化和适应各种应用场景要求的问题,提出了一种单电感多输入多输出的升压?步笛剐?DC??DC转换器,以采集多种能量为可穿戴设备供电。由于转换器既需要高的效率,又需要稳定的负载电压,提出了结合峰值电感电流控制策略和基于阈值变频策略的峰值电感电流脉冲频率调制技术。峰值电感电流脉冲频率调制技术根据各输入输出端口状态来改变能量传输频率,从而实现各能量源最大功率点追踪和负载端电压的调制;同时,通过控制每次能量传递时流过电感的峰值电流大小,提高转换效率并降低输出电压纹波。此外,采用两种低功耗控制策略以降低控制电路功耗:使用低供电电压为控制电路供电;令部分控制电路断续工作。采用华润上华CMOS 0.18 μm工艺完成了转换器电路及版图设计,并进行了仿真验证。后仿真结果表明,在0.2~3 V输入电压范围和0.001~3 mW负载范围内,转换器效率能够保持在73.8%以上,控制电路功耗小于300 nW。
A single??inductor multi??input??multi??output buck??boost DC??DC converter is designed for multi??source energy harvesting according to wearable devices’ demand for miniaturization and adaption to different environments. To achieve high efficiency and stable voltage for the load, inductor??peak??current pulse??frequency modulation technology is proposed to control the converter via combining inductor??peak??current control (IPCC) strategy and the threshold??based variable??frequency (TBVF) strategy. The inductor??peak??current pulse??frequency modulation technology changes the frequency of the energy transformation according to the states of inputs and outputs to implement the maximum power point tracking and to regulate the output voltage. At the same time, it controls the peak current of the inductor to improve the efficiency and to decrease the output voltage ripple. Furthermore, two kinds of low power control strategies are implemented to reduce the power consumption of the control circuits: adopting low voltage control circuit and discontinuously working circuit modules. Finally, the converter circuit and layout are designed and verified in the CSMC 0.18 μm process. Simulation results after layout parasitic extraction show that the efficiency of the converter is above 73.8% under the input voltage from 0.2 V to 3 V with load varying from 0.001 to 3 mW and the power consumption of control circuits is less than 300 nW
Kvasiresonant DC-DC Converter with Switching at Zero Current - Part 1
P. Vorel
Radioengineering , 1998,
Abstract: A kvasiresonant DC - DC converter and its control circuits are proposed. The relations useful for design of the converter will be deduced in the part 2. The fundamental idea of the converter is the switching -on and -off a transistor at zero current. In this way the switching losses are eliminated. It enables to design a converter with a large output power (several kW), high switching frequency (about 200 kHz), very good efficiency and low radiation.
A Protection Circuit for DC-DC Converter with Voltage Doubler
D.Elangovan,A.Gopi,Dr.R.Saravanakumar
International Journal of Engineering and Technology , 2012,
Abstract: This paper proposes a method to obtain a protected voltage gain by employing a protection circuit for the voltage doubler or multiplier circuit in an isolated tyde DC-DC Converter. The entire set up consists of a phase shift converter with a protected bridge/voltage doubler rectifier on the output side. The operating frequency of the phase shift converter is 20-25kHz (depending on the requirement of the application) which is high enough to improve the efficiency. Ferrite core transformer is used in place of ordinary air core transformer, which is small in size with number of turns of the transformer is reduced and the overall power density is increased. The doubler circuit consists of electrolytic capacitors, which are rated at 400V in order to comply with IEC65 requirements. This paper proposes an “electrolytic capacitor protection circuit”, which enables the voltage rating of the electrolytics to be reduced to 250V. This circuit results in cost savings of more than 50% in the price of the electrolytic filter capacitors. The circuits were simulated using PSPICE SOFTWARE and the following results were obtained. For an input voltage of 200V, an output of 200V and400V were obtained in bridge mode and doubler mode respectively.
Kvasiresonant DC-DC Converter with Switching at Zero Current - Part 2
P. Vorel
Radioengineering , 1998,
Abstract: A kvasiresonant DC - DC converter and its control circuits were proposed in the part 1 of the article. The relations useful for design of the converter will be deduced in this part 2. Relations and their numbers of the part 1 will be accepted.
An ZVS DC-DC converter for High voltage and Efficiency gain With Reduced Ripple Current  [PDF]
S.Freeda Angeline Rachel,J.Jency Joseph
International Journal of Engineering and Advanced Technology , 2013,
Abstract: The power-generation market, has shown obvious growth. However, a high voltage and efficiency gain is essential for the fuel cell and PV panel and for other appliances. The high step –up converter in the proposed converter provides ripple- free input current. The full bridge converter provides high voltage gain. An APWM Full Bridge Boost converters are widely used in application where the output voltage is considerably higher than the input voltage. Zero Voltage Switching(ZVS )is typically implemented in the switches.ZVS APWM DC-DC Full bridge converter that does not have any drawbacks of that other converters of this type have such as complicated auxillary circuit,.increased current stress in the main power switches and the load dependent ZVS operation. In this proposed method an interleaved technique of Boost and Full Bridge converter is used..The different modes of operation of MOSFET has been discussed.. Moreover converter has high efficiency because of soft switching operation in switches. A 24V input voltage, 350V output voltage, and 168W output power simulation circuit of the proposed converter has been implemented and its efficiency is up to 87.5%
Analysis of symmetrical dynamic phenomenon of peak and valley current-mode controlled switching DC-DC converters
峰值/谷值电流型控制开关DC-DC变换器的对称动力学现象分析

Zhou Guo-Hu,Xu Jian-Ping,Bao Bo-Cheng,
周国华
,许建平,包伯成

物理学报 , 2010,
Abstract: Peak current and valley current controlled switching DC-DC converters show symmetrical dynamic phenomenon within a wide circuit parameter range. The unified discrete iterative map model of peak current and valley current controlled buck, boost, and buck-boost converters is established, and the unified piecewise smooth iterative map and their corresponding characteristic equations are also derived. The forward and inverse bifurcation diagrams and Lyapunov exponent spectrums with duty ratio as parameter are obtained by numerical simulation. The research results indicate that the bifurcation diagrams and Lyapunov exponent of peak and valley current-mode controlled switching converters show symmetrical dynamic phenomenon corresponding to a symmetrical point or a symmetrical axis. The numerical simulation results are verified by the time-domain simulation, which further indicates that with the duty ratio varying, the peak and valley current-mode controlled switching converter reveals a symmetrical dynamic phenomenon, or a symmetrical dynamic phenomenon accompanying an asymmetrical dynamic phenomenon, or an asymmetrical dynamic phenomenon.
Analysis of symmetrical dynamic phenomenon of peak and valley current-mode controlled switching DC-DC converters
峰值/谷值电流型控制开关DC-DC变换器的对称动力学现象分析

Zhou Guo-Hu,Xu Jian-Ping,Bao Bo-Cheng,
周国华
,许建平,包伯成

中国物理 B , 2010,
Abstract: Peak current and valley current controlled switching DC-DC converters show symmetrical dynamic phenomenon within a wide circuit parameter range. The unified discrete iterative map model of peak current and valley current controlled buck, boost, and buck-boost converters is established, and the unified piecewise smooth iterative map and their corresponding characteristic equations are also derived. The forward and inverse bifurcation diagrams and Lyapunov exponent spectrums with duty ratio as parameter are obtained by numerical simulation. The research results indicate that the bifurcation diagrams and Lyapunov exponent of peak and valley current-mode controlled switching converters show symmetrical dynamic phenomenon corresponding to a symmetrical point or a symmetrical axis. The numerical simulation results are verified by the time-domain simulation, which further indicates that with the duty ratio varying, the peak and valley current-mode controlled switching converter reveals a symmetrical dynamic phenomenon, or a symmetrical dynamic phenomenon accompanying an asymmetrical dynamic phenomenon, or an asymmetrical dynamic phenomenon.
A NEW SOFT-SWITCHING ACTIVE CLAMP SCHEME FOR FULL-BRIDGE ISOLATED CURRENT FED DC-DC CONVERTER FED DRIVES
M.Sasikumar,M.Geetha
Indian Streams Research Journal , 2012,
Abstract: This paper presents on a new high power full bridge isolated current fed dc/dc Converter with an active clamp. A proposed current fed dc/dc converter with high efficiency and voltage boosting capability is designed for use in the interface between a low voltage fuel cell source and a high voltage dc bus for inverters.ZVS scheme in all active switches is achieved for using a soft switching scheme. The switching losses and the conduction losses are reduced and the performance of the drive system should be increased from the proposed model. The proposed converter system is controlled by SPWM Technique. The simulation results are carried out and presented.
Study on the Control Algorithm of Two-Stage DC-DC Converter for Electric Vehicles  [PDF]
Changhao Piao,Chao Jiang,Hongtao Qiao,Chongdu Cho,Sheng Lu
Advances in Mechanical Engineering , 2014, DOI: 10.1155/2014/203793
Abstract: The fast response, high efficiency, and good reliability are very important characteristics to electric vehicles (EVs) dc/dc converters. Two-stage dc-dc converter is a kind of dc-dc topologies that can offer those characteristics to EVs. Presently, nonlinear control is an active area of research in the field of the control algorithm of dc-dc converters. However, very few papers research on two-stage converter for EVs. In this paper, a fixed switching frequency sliding mode (FSFSM) controller and double-integral sliding mode (DISM) controller for two-stage dc-dc converter are proposed. And a conventional linear control (lag) is chosen as the comparison. The performances of the proposed FSFSM controller are compared with those obtained by the lag controller. In consequence, the satisfactory simulation and experiment results show that the FSFSM controller is capable of offering good large-signal operations with fast dynamical responses to the converter. At last, some other simulation results are presented to prove that the DISM controller is a promising method for the converter to eliminate the steady-state error. 1. Introduction Depleting fossil fuel supply and increasing regulations on greenhouse continue to pressure the automotive industry to transition toward more sustainable energy sources [1]. Due to numerous advantages in energy conservation and environmental protection, electrified vehicles which include battery electric vehicles (BEVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (PHEVs) have been actively studied and developed and are widely viewed as an important transition towards sustainable transportation [1–3]. The development of EVs power electronics system control, composed of dc-ac inverters and dc-dc converters, appeals to large numbers of researchers in the modern industry. A dc-ac inverter supplies the high power electric vehicle motors torques of the propulsion system and utility loads, whereas a dc-dc converter supplies conventional low-power and low-voltage loads [4]. As an important component of EVs, dc-dc converter is added to make the power battery and inverter work harmoniously. Although a lot of methods are used to provide monitoring, diagnosis, and control functions to enhance the operations of battery packs [1–3, 5, 6], it is necessary to study the dc-dc converter to ensure its stability and reliability. Two-stage dc-dc converter topologies have recently begun to receive interest in high input voltage, low voltage/high current output dc-dc conversion [7–10]. Generally, the two-stage topologies
High Efficiency Realization of a DC-DC Converter at Light Loads for Portable Applications
便携应用DC-DC轻负载高效率的实现

Yuan Bing,Lai Xinquan,Li Yanming,Ye Qiang,Wang Hongyi,Jia Xinzhang,
袁冰
,来新泉,李演明,叶强,王红义,贾新章

半导体学报 , 2008,
Abstract: A novel control structure for a DC-DC converter is presented.At light loads,the chip enters power save mode automatically and works in fixed peak current mode with standby intervals by detecting the feedback voltage.It reduces the average quiescent and switching power loss greatly,which increases efficiency at light loads and extends battery life in portable systems.Internal synchronous rectification eliminates the need for a Schottky diode and increases efficiency further.A DC-DC buck converter with the pr...
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